@@ -1,193 +1,76 @@
1use std::collections::{HashMap, HashSet};
1use std::collections::{HashMap, HashSet};
2use std::path::{Path, PathBuf};
3use std::path::{Path, PathBuf};
5use crate::ast::*;
5use crate::ast::*;
6−use crate::diagnostic::code;
6+use crate::syntax::{self, Syntax};
7−pub use crate::diagnostic::{Diagnostic, Severity};
8−use crate::interp::{self, Sink};
9−use crate::syntax::{self, DirectiveArgs, LetForm, NodeKind, Segment, Tree};
10−use crate::value::{self, Value};
12// ---------------------------------------------------------------------------
8// ---------------------------------------------------------------------------
13// Public types
9// Public types
14// ---------------------------------------------------------------------------
10// ---------------------------------------------------------------------------
12+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
20+#[derive(Debug, Clone)]
21+pub struct Diagnostic {
23+ pub column: Option<usize>,
25+ pub severity: Severity,
26+ pub source_line: Option<String>,
16pub struct ParseResult {
29pub struct ParseResult {
17 pub document: Document,
30 pub document: Document,
18 pub diagnostics: Vec<Diagnostic>,
31 pub diagnostics: Vec<Diagnostic>,
19 pub included_files: Vec<PathBuf>,
32 pub included_files: Vec<PathBuf>,
22−/// An error that stops one line from being evaluated.
35+#[derive(Debug)]
23−type ParseError = Diagnostic;
36+struct ParseError {
25−// ---------------------------------------------------------------------------
27−// ---------------------------------------------------------------------------
31− /// The parameters in the order they are declared; one without a
32− /// default is required.
33− params: Vec<syntax::Param>,
34− /// The definition's line and its text (when it is one physical line),
35− /// and its node, for diagnostics about a default.
36 line: usize,
37 line: usize,
37− source: Option<String>,
38+ message: String,
39− body: Vec<syntax::Node>,
40− /// The file it is defined in, when that isn't the file being compiled
41− /// (see `ParseContext::current_file`).
42− file: Option<String>,
43− /// The slots its body declares (`@slot NAME`), in order.
45− /// Whether its body has a `@children` for the content of a call.
47− /// Its scoped `@style`: its class (`hl-fn-NAME-HASH`), and the
48− /// stylesheet nested under it, written into the page once the function
49− /// is called (see `Document::scoped_css`).
50− scoped: Option<(String, String)>,
51− /// What was visible where it was defined: its body and its defaults
52− /// see this, plus its parameters.
54− /// It is named like a built-in element and its body calls that name
55− /// outside any `@if`, meaning the element (`@let @nav` around `@nav`):
56− /// it would call itself forever, so a call writes nothing (the
57− /// definition's error says so).
61−impl FnDef {
41+impl fmt::Display for ParseError {
62− fn is_param(&self, name: &str) -> bool {
42+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
63− self.params.iter().any(|p| p.name == name)
43+ write!(f, "line {}: {}", self.line, self.message)
67−/// What a name means: every `@let`, parameter, loop variable and `@data`
47+// ---------------------------------------------------------------------------
68−/// binds one, and they share one namespace.
48+// Internal types
69−#[derive(Clone)]
49+// ---------------------------------------------------------------------------
72− Bundle(Rc<Vec<Attribute>>),
76−/// The names visible at a line: one frame per block it is in (the
77−/// standard library, the file, an element's children, an `@if` branch, an
78−/// iteration of `@each`, a function's body), the innermost last. A
79−/// definition goes into the innermost frame, so it is visible from its
80−/// line to the end of its block. A function keeps the frames visible
81−/// where it is defined; a frame is shared until one side changes it.
82−#[derive(Clone, Default)]
84− frames: Vec<Rc<HashMap<String, Binding>>>,
89− self.frames.push(Rc::default());
96− /// Give `name` a meaning in the innermost frame, replacing what it
97− /// meant there and hiding what it means outside it.
98− fn define(&mut self, name: &str, binding: Binding) {
99− if self.frames.is_empty() {
102− if let Some(frame) = self.frames.last_mut() {
103− Rc::make_mut(frame).insert(name.to_string(), binding);
107− /// What `name` means here: the innermost definition.
108− fn get(&self, name: &str) -> Option<&Binding> {
109− self.frames.iter().rev().find_map(|frame| frame.get(name))
112− fn value(&self, name: &str) -> Option<&Value> {
113− match self.get(name)? {
114− Binding::Value(value) => Some(value),
119− fn bundle(&self, name: &str) -> Option<&Rc<Vec<Attribute>>> {
120− match self.get(name)? {
121− Binding::Bundle(attrs) => Some(attrs),
126− fn function(&self, name: &str) -> Option<&Rc<FnDef>> {
127− match self.get(name)? {
128− Binding::Function(function) => Some(function),
133− /// Every name visible here, with what it means.
134− fn visible(&self) -> HashMap<&str, &Binding> {
135− let mut names = HashMap::new();
136− for frame in &self.frames {
137− for (name, binding) in frame.iter() {
138− names.insert(name.as_str(), binding);
144− /// The names of the values visible here.
145− fn value_names(&self) -> Vec<&str> {
148− .filter(|(_, binding)| matches!(binding, Binding::Value(_)))
149− .map(|(name, _)| name)
153− /// The names of the bundles visible here.
154− fn bundle_names(&self) -> Vec<&str> {
157− .filter(|(_, binding)| matches!(binding, Binding::Bundle(_)))
158− .map(|(name, _)| name)
163−impl interp::Scope for Env {
51+#[derive(Clone)]
164− fn get(&self, name: &str) -> Option<Value> {
52+struct FnDef {
165− self.value(name).cloned()
53+ params: Vec<String>,
166− }
54+ defaults: HashMap<String, String>,
169struct ParseContext {
58struct ParseContext {
170 /// Source line currently being parsed, for diagnostics raised deep
59 /// Source line currently being parsed, for diagnostics raised deep
171 /// inside helpers that don't take a line number.
60 /// inside helpers that don't take a line number.
172 current_line: usize,
61 current_line: usize,
173− /// What the `@page` said, once one has run
62+ /// Functions whose body has a scoped @style block.
174− page: Option<Page>,
63+ scoped_functions: std::collections::HashSet<String>,
175− /// Where that `@page` is, for the error a second one gets
64+ page_title: Option<String>,
176− page_at: Option<String>,
65+ lang: Option<String>,
66+ favicon: Option<String>,
177 meta_tags: Vec<(String, String)>,
67 meta_tags: Vec<(String, String)>,
178 head_blocks: Vec<String>,
68 head_blocks: Vec<String>,
179− /// The first `@meta` or `@head` that ran, for the warning a file
69+ variables: HashMap<String, String>,
180− /// without `@page` gets: a fragment has no `<head>` for them.
70+ defines: HashMap<String, Vec<Attribute>>,
181− head_at: Option<usize>,
71+ functions: HashMap<String, FnDef>,
182− /// What each name means at the line being evaluated.
184− /// Every function whose definition ran, by name (the last one), for
185− /// the checks of code that never runs.
186− defined_functions: HashMap<String, Rc<FnDef>>,
187 css_vars: Vec<(String, String)>,
72 css_vars: Vec<(String, String)>,
188 custom_css: Vec<String>,
73 custom_css: Vec<String>,
189− /// The scoped `@style` of each function called so far
190− scoped_css: Vec<String>,
191 og_tags: Vec<(String, String)>,
74 og_tags: Vec<(String, String)>,
192 diagnostics: Vec<Diagnostic>,
75 diagnostics: Vec<Diagnostic>,
193 base_path: Option<PathBuf>,
76 base_path: Option<PathBuf>,
@@ -207,550 +90,39 @@ struct ParseContext {
207 fn_lines: HashMap<String, usize>,
90 fn_lines: HashMap<String, usize>,
208 /// Line numbers of attribute bundle definitions (name -> line)
91 /// Line numbers of attribute bundle definitions (name -> line)
209 define_lines: HashMap<String, usize>,
92 define_lines: HashMap<String, usize>,
210− /// Syntax nodes evaluated at least once, by id.
93+ /// Canonical URL
211− visited: HashSet<usize>,
94+ canonical: Option<String>,
212− /// The id the next parsed tree starts at, so ids are unique across
95+ /// Base URL for relative links
213− /// the file, its includes and the standard library.
96+ base_url: Option<String>,
215− /// The file's tree and those of the files it includes, with the
216− /// include chain that leads to each, for the checks of code that never
218− trees: Vec<(Rc<Tree>, Option<String>)>,
219− /// The files each `@include` line brought in (by the line's node id),
220− /// with the include chain that leads to each, so the checks of
221− /// `@slot` and `@children` see an included file's lines where the
222− /// `@include` is written.
223− included_by: Rc<IncludedBy>,
224− /// Every function defined anywhere in the file or the files it
225− /// includes, whether or not its definition runs.
226− namespace: HashSet<String>,
227− /// The line being evaluated, and its text as written when it is one
228− /// physical line, for diagnostics that point at a column.
229− current_source: (usize, Option<String>),
230− /// Variable diagnostics already reported, so a line evaluated many
231− /// times (in a loop, in a function) reports each problem once.
232− /// Keyed by the syntax node (ids are unique across files), line,
233− /// column and message.
234− reported: HashSet<(usize, usize, Option<usize>, String)>,
235− /// The id of the syntax node being evaluated.
236− current_node: usize,
237− /// The file whose lines are being evaluated, when it isn't the file
238− /// being compiled: the standard library, or an included file (by its
240− current_file: Option<String>,
241− /// A call went deeper than [`MAX_CALL_DEPTH`]: the calls it is nested
242− /// in expand to nothing, until the outermost one returns.
244− /// A bundle's attributes are being read: a name that could be a
245− /// parameter of the function the bundle is passed to is checked where
246− /// the bundle is used instead.
248− /// `@page`'s attributes are being read: a name close to `favicon` is
249− /// a misspelled word of `@page`'s.
253−/// How deeply function calls may nest, so that a function that calls
254−/// itself without an `@if` that stops it is an error instead of a hang.
255−const MAX_CALL_DEPTH: usize = 64;
257−/// A CSS rule at the top level of a stylesheet that starts with `&`
258−/// (outside any `{}`, strings and comments).
259−fn has_top_level_ampersand(css: &str) -> bool {
260− let mut depth = 0usize;
261− let mut chars = css.chars().peekable();
262− let mut at_rule_start = true;
263− while let Some(c) = chars.next() {
265− '/' if chars.peek() == Some(&'*') => {
268− for c in chars.by_ref() {
269− if last == '*' && c == '/' {
277− for d in chars.by_ref() {
284− '}' => depth = depth.saturating_sub(1),
285− '&' if depth == 0 && at_rule_start => return true,
288− at_rule_start = match c {
289− '{' | '}' | ';' => true,
290− c if c.is_whitespace() => at_rule_start,
297−/// Whether a file is a library (see [`Tree::is_library`]), with the files
298−/// its `@include` lines name read relative to `base`.
301− base: Option<&Path>,
302− ctx: &mut ParseContext,
303− seen: &mut Vec<PathBuf>,
305− tree.is_library_with(&mut |path| {
306− if path.contains('$') {
309− let resolved = base.map_or_else(|| PathBuf::from(path), |base| base.join(path));
310− if seen.contains(&resolved) {
313− seen.push(resolved.clone());
314− let Ok(text) = ctx.read_file(&resolved) else {
317− let included = syntax::parse(&text);
318− is_library_file(&included, resolved.parent(), ctx, seen)
322−/// The frames around the file's top level: the standard library's and
323−/// the file's own (see [`load_prelude`]).
324−const FILE_FRAMES: usize = 2;
326/// Evaluates a syntax tree (see `syntax.rs`) into the document's nodes.
99/// Evaluates a syntax tree (see `syntax.rs`) into the document's nodes.
327struct Evaluator;
100struct Evaluator;
329impl ParseContext {
102impl ParseContext {
330− /// Bind a value to `name` in the innermost block.
103+ /// Evaluate an expression (see `expr.rs`), reporting errors at `line`.
331− fn bind(&mut self, name: &str, value: Value) {
104+ fn eval(&mut self, src: &str, line: usize) -> Option<crate::expr::Value> {
332− self.env.define(name, Binding::Value(value));
335− /// Evaluate an expression (see `expr.rs`) written at `line` and
336− /// `column` (when known), reporting its errors there.
341− column: Option<usize>,
342− ) -> Option<crate::expr::Value> {
343 track_var_refs(src, &mut self.used_variables);
105 track_var_refs(src, &mut self.used_variables);
344− match crate::expr::eval(src, &self.env) {
106+ let vars = &self.variables;
107+ let result = crate::expr::eval(src, &|name: &str| lookup(vars, name));
345 Ok(value) => Some(value),
109 Ok(value) => Some(value),
346− Err(error) => {
110+ Err(message) => {
347− // Without the line to point into, show the expression
111+ self.diagnostics.push(Diagnostic {
348− let shown = matches!(&self.current_source, (current, Some(_)) if *current == line);
112+ line,
349− let before = self.diagnostics.len();
113+ column: None,
350− self.report(error.at(0), line, column);
114+ message: format!("invalid expression: {}", message),
351− if !shown && let Some(diagnostic) = self.diagnostics.get_mut(before) {
115+ severity: Severity::Error,
352− diagnostic.source_line = Some(src.into());
116+ source_line: Some(src.to_string()),
359 /// Evaluate a condition; an invalid one is reported and counts as false.
123 /// Evaluate a condition; an invalid one is reported and counts as false.
360− fn condition(&mut self, src: &str, line: usize, column: Option<usize>) -> bool {
124+ fn condition(&mut self, src: &str, line: usize) -> bool {
361− self.eval(src, line, column)
125+ self.eval(src, line).is_some_and(|value| value.truthy())
362− .is_some_and(|value| value.truthy())
365− /// Fill in one slot of htmlang text written at `line` and `column`
366− /// (when known), for `sink`: its escapes stand for themselves and its
367− /// variables are filled in (see `interp.rs`). What can't be filled is
368− /// left as written and reported; the flag says whether everything was
374− column: Option<usize>,
376− ) -> (String, bool) {
377− let (filled, ok) = self.fill_protected(raw, line, column, sink);
378− (restore_escapes(&filled), ok)
381− /// [`fill`](Self::fill) for text.
382− fn interpolate_text(&mut self, raw: &str, line: usize, column: Option<usize>) -> String {
383− self.fill(raw, line, column, Sink::Text).0
386− /// [`fill`](Self::fill), with the escapes still placeholders (see
387− /// [`protect_escapes`]).
392− column: Option<usize>,
394− ) -> (String, bool) {
395− let mut protected = protect_escapes(raw);
396− if sink == Sink::Css {
397− protected = keep_css_string_escapes(&protected);
399− if !protected.contains('$') {
400− return (protected, true);
402− track_var_refs(&protected, &mut self.used_variables);
403− let (out, problems) = interp::interpolate_for(&protected, &self.env, sink);
404− let filled = problems.is_empty();
405− for mut problem in problems {
406− match &mut problem {
407− interp::Problem::Undefined { offset, .. }
408− | interp::Problem::CustomProperty { offset, .. }
409− | interp::Problem::Invalid { offset, .. }
410− | interp::Problem::Record { offset, .. } => {
411− // An offset into the protected text, as one into `raw`
412− *offset = protected[..*offset]
414− .map(|c| escape_of(c).map_or(c.len_utf8(), str::len))
418− self.report(problem, line, column);
423− /// Fill in a value slot (an attribute's value, a `@let` value, `@meta`'s
424− /// value) for `sink`, and say whether it is quoted text: one `"..."`, or
425− /// one variable that holds quoted text. Quoted text keeps its quotes
431− column: Option<usize>,
433− ) -> (String, Option<Quoted>, bool) {
434− if let Some(inner) = syntax::quoted_string(raw) {
435− let (css, ok) = self.fill(raw, line, column, Sink::Css);
436− // Already reported by the CSS pass, so filled in quietly
437− let (text, _) = interp::interpolate(&protect_escapes(inner), &self.env);
438− let quoted = Quoted {
439− text: restore_escapes(&text),
442− let out = match sink {
443− Sink::Css => quoted.css.clone(),
444− Sink::Text => quoted.text.clone(),
446− return (out, Some(quoted), ok);
448− let (out, ok) = self.fill(raw, line, column, sink);
449− let quoted = whole_reference(raw, &self.env).and_then(|path| {
450− match interp::resolve(&path, &self.env)? {
451− Value::Quoted(quoted) => Some(quoted),
458− /// The value of a value slot (a `@let` value, the source of `@each`, a
459− /// parameter's value or default), written at `line` and `column`:
461− /// - exactly one `$name` or `${...}` is the value it holds or gives,
462− /// whatever its type (a list, a record, quoted text);
463− /// - one `"..."` is quoted text;
464− /// - commas outside quotes, brackets and `${...}`, and not escaped
465− /// (`\,`), make a list, which prints as written;
466− /// - `A..B` or `A..B step N` with whole numbers is a range;
467− /// - anything else is text, with its variables filled in.
469− /// What can't be filled in is reported; the flag says whether
471− fn slot_value(&mut self, raw: &str, line: usize, column: Option<usize>) -> (Value, bool) {
472− let trimmed = raw.trim();
473− let column = column.map(|c| c + (raw.len() - raw.trim_start().len()));
474− if let Some(value) = self.whole_value(trimmed, line, column) {
477− if syntax::quoted_string(trimmed).is_some() {
478− let (text, quoted, ok) = self.fill_value(trimmed, line, column, Sink::Text);
479− return (quoted.map_or(Value::Str(text), Value::Quoted), ok);
481− let parts = syntax::split_list(trimmed);
482− if parts.len() > 1 {
483− // Each item is a value of its own; the list prints as written
484− let mut items = Vec::new();
485− let mut written = String::new();
489− let item = &trimmed[part.clone()];
490− let lead = item.len() - item.trim_start().len();
491− written.push_str(&trimmed[end..part.start + lead]);
492− end = part.start + lead + item.trim().len();
493− if item.trim().is_empty() {
496− let at = column.map(|c| c + part.start + lead);
497− let (value, text, filled) = self.item_value(item.trim(), line, at);
499− written.push_str(&text);
502− written.push_str(&trimmed[end..]);
503− let list = value::List {
504− items: Rc::new(items),
505− written: Some(written.into()),
507− return (Value::List(list), ok);
509− let (text, ok) = self.fill(trimmed, line, column, Sink::Text);
510− match value::written_range(&text) {
511− Some(Ok(range)) => (range, ok),
512− Some(Err(message)) => {
514− interp::Problem::Invalid { message, offset: 0 },
518− (Value::list(Vec::new()), false)
520− None => (Value::Str(text), ok),
524− /// An item of a list written in the source (see
525− /// [`slot_value`](Self::slot_value)), and how it is written in the
531− column: Option<usize>,
532− ) -> (Value, String, bool) {
533− let (value, ok) = match self.whole_value(item, line, column) {
534− Some(value) => value,
535− None if syntax::quoted_string(item).is_some() => {
536− let (text, quoted, ok) = self.fill_value(item, line, column, Sink::Text);
537− (quoted.map_or(Value::Str(text), Value::Quoted), ok)
540− let (text, ok) = self.fill(item, line, column, Sink::Text);
541− (Value::Str(text), ok)
544− // Quoted text keeps its quotes in the list's text, as written
547− .map_or_else(|| value.to_string(), str::to_string);
551− /// The value of a slot that is exactly one `$name` or `${...}`, with its
552− /// type; `None` when it is anything else.
557− column: Option<usize>,
558− ) -> Option<(Value, bool)> {
559− let after = raw.strip_prefix('$')?;
560− let (reference, len) = interp::reference(after, &self.env)?;
561− if len != after.len() {
564− track_var_refs(raw, &mut self.used_variables);
565− let problem = match reference {
566− interp::Reference::Var(path) => match interp::resolve(&path, &self.env) {
567− Some(value) => return Some((value, true)),
568− None => interp::Problem::Undefined {
573− interp::Reference::Expr(source) => match crate::expr::eval(source, &self.env) {
574− Ok(value) => return Some((value, true)),
575− Err(crate::expr::Error::Invalid(message)) => {
576− interp::Problem::Invalid { message, offset: 0 }
578− Err(error) => error.at(2),
581− self.report(problem, line, column);
582− Some((Value::Str(raw.to_string()), false))
585− /// Report a variable that can't be filled in, or an invalid `${...}`,
586− /// at `offset` from `column`.
587− fn report(&mut self, problem: interp::Problem, line: usize, column: Option<usize>) {
588− let (line_text, column) = match &self.current_source {
589− // The column is only shown with the line it points into
590− (current, Some(text)) if *current == line => (Some(text.clone()), column),
593− let diagnostic = match problem {
594− interp::Problem::Undefined { name, offset } => {
595− let column = column.map(|c| c + offset);
596− let mut diagnostic = self.undefined(&name, line);
597− if let Some(column) = column {
598− diagnostic = diagnostic.column(column);
602− interp::Problem::Invalid { message, offset } => {
603− let diagnostic = Diagnostic::error(
604− code::INVALID_EXPRESSION,
606− format!("invalid expression: {}", message),
609− Some(column) => diagnostic.column(column + offset),
613− interp::Problem::CustomProperty { name, offset } => {
614− let diagnostic = Diagnostic::error(
615− code::INVALID_VALUE,
617− interp::custom_property_message(&name),
619− .subject(format!("${}", name))
620− .suggest(Some(format!("var({})", name)));
622− Some(column) => diagnostic.column(column + offset),
626− interp::Problem::Record { message, offset } => {
627− let diagnostic = Diagnostic::error(code::INVALID_VALUE, line, message);
629− Some(column) => diagnostic.column(column + offset),
634− let diagnostic = match line_text {
635− Some(text) => diagnostic.source(text),
638− self.push_once(diagnostic);
641− /// Report a diagnostic unless the node being evaluated already did,
642− /// so a line evaluated many times (in a loop, in a function) reports
643− /// each problem once.
644− fn push_once(&mut self, diagnostic: Diagnostic) {
649− diagnostic.message.clone(),
651− if self.reported.insert(key) {
652− self.diagnostics.push(diagnostic);
656− /// The error for `$name` with no definition: what the name is if it is
657− /// something else, or the closest defined name.
658− fn undefined(&mut self, name: &str, line: usize) -> Diagnostic {
659− if self.env.bundle(name).is_some() {
660− // Reported here, so not also as unused
661− self.used_defines.insert(name.to_string());
662− return Diagnostic::error(
663− code::UNDEFINED_VARIABLE,
666− "'${}' is an attribute bundle, not a value: it goes in an attribute list \
667− as a whole attribute, `[${}]`",
673− if self.env.function(name).is_some() {
674− self.used_functions.insert(name.to_string());
675− return Diagnostic::error(
676− code::UNDEFINED_VARIABLE,
679− "'${}' is a function, not a value: it is called as an element, `@{}`",
685− // `$i-label` where `$i` is defined: a `-` joins a name
686− if let Some((defined, rest)) = name
688− .map(|(i, _)| (&name[..i], &name[i..]))
689− .find(|(before, _)| self.env.value(before).is_some())
691− return Diagnostic::error(
692− code::UNDEFINED_VARIABLE,
695− "undefined variable '${}': a `-` is part of a name. For '${}' followed \
696− by '{}', write `${{{}}}{}`",
697− name, defined, rest, defined, rest
702− let suggestion = suggest_var_name(name, &self.env.value_names());
703− let message = match (&suggestion, self.let_lines.get(name)) {
704− (Some(closest), _) => format!(
705− "undefined variable '${}', did you mean '${}'?",
708− // Defined, but not where this line can see it
709− (None, Some(_)) => format!(
710− "undefined variable '${}': a `@let` defines it, but not where this line \
711− can see it. A definition is visible from its line to the end of its \
712− block, and a function's body sees what is defined above the function",
715− (None, None) => format!("undefined variable '${}'", name),
717− Diagnostic::error(code::UNDEFINED_VARIABLE, line, message)
719− .suggest(suggestion)
722− /// Note the node being evaluated, for diagnostics.
723− fn enter(&mut self, node: &syntax::Node) {
724− self.current_line = node.span.line;
725− self.current_node = node.id;
727− (node.line_count <= 1).then(|| format!("{}{}", " ".repeat(node.indent), node.source));
728− self.current_source = (node.span.line, text);
731− /// Parse a file's text into a tree whose ids don't clash with the
732− /// trees parsed before it.
733− fn parse_tree(&mut self, text: &str) -> Rc<Tree> {
734− let tree = syntax::parse_from(text, self.next_id);
735− self.next_id = tree.end_id;
739− /// Read a file (once), relative to the current file.
740− fn read_file(&mut self, resolved: &Path) -> std::io::Result<String> {
741− if let Some(cached) = self.file_cache.get(resolved) {
742− return Ok(cached.clone());
744− let text = std::fs::read_to_string(resolved)?;
745− self.file_cache.insert(resolved.to_path_buf(), text.clone());
749− fn resolve(&self, filename: &str) -> PathBuf {
750− match &self.base_path {
751− Some(base) => base.join(filename),
752− None => PathBuf::from(filename),
@@ -759,19 +131,11 @@ impl ParseContext {
759const PRELUDE: &str = include_str!("std.hl");
131const PRELUDE: &str = include_str!("std.hl");
761fn load_prelude(ctx: &mut ParseContext) {
133fn load_prelude(ctx: &mut ParseContext) {
762− // The library's definitions are in a block of their own, around the
134+ let _ = Evaluator.eval_block(&syntax::parse(PRELUDE), ctx);
763− // file's, so the file's own `@let` of the same name hides them
765− let tree = ctx.parse_tree(PRELUDE);
766− collect_namespace(&tree.nodes, None, &mut HashSet::new(), ctx);
767− ctx.current_file = Some("std.hl".to_string());
768− let _ = Evaluator.eval_block(&tree.nodes, ctx);
769− ctx.current_file = None;
770 // Library definitions aren't the file's own: never report them unused.
135 // Library definitions aren't the file's own: never report them unused.
771 ctx.fn_lines.clear();
136 ctx.fn_lines.clear();
772 ctx.define_lines.clear();
137 ctx.define_lines.clear();
773 ctx.let_lines.clear();
138 ctx.let_lines.clear();
777pub fn parse(input: &str) -> ParseResult {
141pub fn parse(input: &str) -> ParseResult {
@@ -779,18 +143,20 @@ pub fn parse(input: &str) -> ParseResult {
781pub fn parse_with_base(input: &str, base_path: Option<&Path>) -> ParseResult {
145pub fn parse_with_base(input: &str, base_path: Option<&Path>) -> ParseResult {
146+ let tree = syntax::parse(input);
782 let mut ctx = ParseContext {
147 let mut ctx = ParseContext {
783 current_line: 0,
148 current_line: 0,
784− page: None,
149+ scoped_functions: std::collections::HashSet::new(),
785− page_at: None,
150+ page_title: None,
786 meta_tags: Vec::new(),
153 meta_tags: Vec::new(),
787 head_blocks: Vec::new(),
154 head_blocks: Vec::new(),
788− head_at: None,
155+ variables: HashMap::new(),
789− env: Env::default(),
156+ defines: HashMap::new(),
790− defined_functions: HashMap::new(),
157+ functions: HashMap::new(),
791 css_vars: Vec::new(),
158 css_vars: Vec::new(),
792 custom_css: Vec::new(),
159 custom_css: Vec::new(),
793− scoped_css: Vec::new(),
794 og_tags: Vec::new(),
160 og_tags: Vec::new(),
795 diagnostics: Vec::new(),
161 diagnostics: Vec::new(),
796 base_path: base_path.map(|p| p.to_path_buf()),
162 base_path: base_path.map(|p| p.to_path_buf()),
@@ -804,85 +170,28 @@ pub fn parse_with_base(input: &str, base_path: Option<&Path>) -> ParseResult {
804 let_lines: HashMap::new(),
170 let_lines: HashMap::new(),
805 fn_lines: HashMap::new(),
171 fn_lines: HashMap::new(),
806 define_lines: HashMap::new(),
172 define_lines: HashMap::new(),
807− visited: HashSet::new(),
173+ canonical: None,
808− next_id: 0,
174+ base_url: None,
810− included_by: Rc::default(),
811− namespace: HashSet::new(),
812− current_source: (0, None),
813− reported: HashSet::new(),
820 load_prelude(&mut ctx);
176 load_prelude(&mut ctx);
821− let tree = ctx.parse_tree(input);
177+ let nodes = Evaluator.eval_block(&tree, &mut ctx);
822− ctx.diagnostics.extend(tree.diagnostics.iter().cloned());
178+ validate_tree(&nodes, None, &mut ctx.diagnostics);
823− ctx.trees.push((tree.clone(), None));
179+ check_unused(&mut ctx);
826− base_path.map(Path::to_path_buf),
827− &mut HashSet::new(),
830− let nodes = Evaluator.eval_block(&tree.nodes, &mut ctx);
831− check_unevaluated(&mut ctx);
832− check_slot_places(&mut ctx);
833− validate_tree(&nodes, None, false, &mut ctx.diagnostics);
834− // A library's definitions are for the files that include it
835− let library = is_library_file(&tree, base_path, &mut ctx, &mut Vec::new());
836− let exported: HashSet<String> = if library {
839− .filter_map(|node| match node.directive().map(|d| &d.args) {
840− Some(DirectiveArgs::Let(def)) => Some(def.name.clone()),
847− check_unused(&mut ctx, &exported);
848− if let (None, Some(line)) = (&ctx.page, ctx.head_at)
851− ctx.diagnostics.push(Diagnostic::warning(
854− "a file without @page is a fragment, which has no <head>: @meta and @head are \
855− left out of it (give the file a @page, or put them in the page that includes it)"
859− dedupe(&mut ctx.diagnostics);
860− // What the file itself defines at its top level
861− let file = ctx.env.frames.last().cloned().unwrap_or_default();
862− let mut variables = HashMap::new();
863− let mut defines = HashMap::new();
864− for (name, binding) in file.iter() {
866− Binding::Value(value) => {
867− variables.insert(name.clone(), value.to_string());
869− Binding::Bundle(attrs) => {
870− defines.insert(name.clone(), attrs.to_vec());
872− Binding::Function(_) => {}
875 ParseResult {
180 ParseResult {
876 document: Document {
181 document: Document {
877− page: ctx.page,
182+ page_title: ctx.page_title,
184+ favicon: ctx.favicon,
878 meta_tags: ctx.meta_tags,
185 meta_tags: ctx.meta_tags,
879 head_blocks: ctx.head_blocks,
186 head_blocks: ctx.head_blocks,
880− variables,
187+ variables: ctx.variables,
881− defines,
188+ defines: ctx.defines,
882 css_vars: ctx.css_vars,
189 css_vars: ctx.css_vars,
883 custom_css: ctx.custom_css,
190 custom_css: ctx.custom_css,
884− scoped_css: ctx.scoped_css,
885 og_tags: ctx.og_tags,
191 og_tags: ctx.og_tags,
192+ canonical: ctx.canonical,
193+ base_url: ctx.base_url,
194+ preload_hints: collect_image_preload_hints(&nodes),
888 diagnostics: ctx.diagnostics,
197 diagnostics: ctx.diagnostics,
@@ -890,882 +199,619 @@ pub fn parse_with_base(input: &str, base_path: Option<&Path>) -> ParseResult {
893−// ---------------------------------------------------------------------------
202+/// Scan nodes for @image elements and generate preload hints for early images.
894−// Code that never runs: an untaken branch, an uncalled function, a loop over
203+fn collect_image_preload_hints(nodes: &[Node]) -> Vec<crate::ast::PreloadHint> {
895−// an empty list
204+ let mut hints = Vec::new();
896−// ---------------------------------------------------------------------------
205+ // Only preload the first few images (above-the-fold heuristic)
206+ collect_images_recursive(nodes, &mut hints, 3);
898−/// Collect the functions defined anywhere in `nodes` and in the files they
210+fn collect_images_recursive(nodes: &[Node], hints: &mut Vec<crate::ast::PreloadHint>, max: usize) {
899−/// include (by a literal path), into `ctx.namespace`.
900−fn collect_namespace(
901− nodes: &[syntax::Node],
902− base: Option<PathBuf>,
903− seen: &mut HashSet<PathBuf>,
904− ctx: &mut ParseContext,
906− let mut includes = Vec::new();
907 for node in nodes {
211 for node in nodes {
908− node.walk(&mut |node| match node.directive().map(|d| &d.args) {
212+ if hints.len() >= max {
909− Some(DirectiveArgs::Let(def)) if matches!(def.form, LetForm::Function(_)) => {
213+ return;
910− ctx.namespace.insert(def.name.clone());
912− Some(DirectiveArgs::Text(Some(path))) if node.is_directive("include") => {
913− includes.push(path.raw.clone());
918− for path in includes {
919− let path = path.trim_matches('"');
920− if path.contains('$') {
923− let resolved = match &base {
215+ if let Node::Element(elem) = node {
924− Some(base) => base.join(path),
216+ if elem.kind == ElementKind::Image
925− None => PathBuf::from(path),
217+ && let Some(ref src) = elem.argument
926− };
218+ && !src.is_empty()
927− if !seen.insert(resolved.clone()) {
219+ && !src.starts_with("data:")
928− continue;
220+ && !src.starts_with('#')
222+ hints.push(crate::ast::PreloadHint {
224+ as_type: "image".to_string(),
228+ collect_images_recursive(&elem.children, hints, max);
930− let Ok(text) = ctx.read_file(&resolved) else {
933− let tree = syntax::parse(&text);
934− let parent = resolved.parent().map(Path::to_path_buf);
935− collect_namespace(&tree.nodes, parent, seen, ctx);
939−/// Check the lines that were never evaluated: element and function names,
233+// ---------------------------------------------------------------------------
940−/// and the attributes of built-in elements (those that don't depend on a
234+// Preprocessing: strip comments/blanks, collapse @raw blocks
941−/// variable). Names that come from data are only checked when evaluated.
235+// ---------------------------------------------------------------------------
942−fn check_unevaluated(ctx: &mut ParseContext) {
236+
943− let trees = std::mem::take(&mut ctx.trees);
237+// ---------------------------------------------------------------------------
944− let mut seen = HashSet::new();
238+// Evaluation
945− for (tree, chain) in &trees {
239+// ---------------------------------------------------------------------------
946− let before = ctx.diagnostics.len();
240+
947− for node in &tree.nodes {
241+impl Evaluator {
948− check_unevaluated_node(node, ctx);
242+ fn eval_block(&mut self, block: &[Syntax], ctx: &mut ParseContext) -> Vec<Node> {
949− }
243+ let mut nodes = Vec::new();
950− let mut found = ctx.diagnostics.split_off(before);
244+ for node in block {
951− if let Some(chain) = chain {
245+ match self.eval(node, ctx) {
952− for d in &mut found {
246+ Ok(Some(new_nodes)) => nodes.extend(new_nodes),
953− d.message = format!("{}\n in {}", d.message, chain);
247+ Ok(None) => {}
248+ // Record the error and go on, to report several in one pass
249+ Err(e) => ctx.diagnostics.push(Diagnostic {
253+ severity: Severity::Error,
254+ source_line: Some(node.source()),
956− // A file included twice is checked twice: report each problem once
258+ nodes
957− found.retain(|d| seen.insert((d.line, d.message.clone())));
958− ctx.diagnostics.extend(found);
963−fn check_unevaluated_node(node: &syntax::Node, ctx: &mut ParseContext) {
261+ /// Evaluate a block in its own scope: `@let` inside doesn't leak out.
964− if !ctx.visited.contains(&node.id) {
262+ fn eval_scoped(&mut self, block: &[Syntax], ctx: &mut ParseContext) -> Vec<Node> {
965− let line = node.span.line;
263+ let saved_vars = ctx.variables.clone();
966− // A reference from code that doesn't run still counts as a use
264+ let nodes = self.eval_block(block, ctx);
967− track_var_refs(&node.source, &mut ctx.used_variables);
265+ ctx.variables = saved_vars;
968− let before = ctx.diagnostics.len();
266+ nodes
969− match &node.kind {
267+ }
970− NodeKind::Element(element) => {
268+
971− for head in &element.chain {
269+ fn eval(&mut self, node: &Syntax, ctx: &mut ParseContext) -> Result<Option<Vec<Node>>, ParseError> {
972− check_head(head, line, ctx);
270+ let line_num = node.line();
973− }
271+ ctx.current_line = line_num;
974− check_unevaluated_content(node, element, ctx);
272+ if !matches!(node, Syntax::Raw { .. })
975− if let Some(text) = &element.text {
273+ && let Some(filter) = old_filter_syntax(&node.source())
976− check_inline_heads(text, line, ctx);
274+ {
275+ ctx.diagnostics.push(Diagnostic {
279+ "`${}|{}` filters are functions now: write `${{{}(${})}}` (run `htmlang upgrade`)",
280+ filter.0, filter.1, filter.1, filter.0
282+ severity: Severity::Warning,
283+ source_line: Some(node.source()),
286+ let (content, current_indent, children) = match node {
287+ Syntax::Raw { text, .. } => return Ok(Some(vec![Node::Raw(text.clone())])),
288+ Syntax::Function { name, params, defaults, body, .. } => {
289+ self.define_function(name, params, defaults, body, line_num, ctx);
292+ Syntax::If { branches } => {
293+ // Every condition is checked (and its errors reported);
294+ // the first that holds picks the branch.
295+ let mut chosen = None;
296+ for branch in branches {
297+ let holds = match &branch.condition {
298+ Some(condition) => ctx.condition(condition, branch.line),
301+ if holds && chosen.is_none() {
302+ chosen = Some(&branch.body);
305+ return Ok(chosen.map(|body| self.eval_scoped(body, ctx)));
979− NodeKind::Text(text) => check_inline_heads(text, line, ctx),
307+ Syntax::Each { header, body, empty, .. } => {
980− // `@page`'s attributes are checked like an element's (a layout's
308+ return self.eval_each(header, body, empty, line_num, ctx).map(Some);
981− // `@page` is in a function that may not run in this file)
982− NodeKind::Directive(syntax::Directive {
984− DirectiveArgs::Page {
985− attrs: Some(list), ..
989− let words: Vec<String> = crate::vocab::PAGE_WORDS
991− .map(|w| w.to_string())
994− check_attrs(&list.attrs, line, ctx, &words);
995− ctx.in_page = false;
996− check_page_tokens(&list.attrs, line, ctx);
998− _ => {}
310+ Syntax::Line { text, indent, children, .. } => (text.clone(), *indent, children),
313+ // --- Directives ---
315+ // Removed syntax gets a pointer to its replacement — unless the
316+ // name is a user function (e.g. `@let divider`).
317+ if content.starts_with('@')
318+ && !ctx.functions.contains_key(extract_element_name(&content))
319+ && let Some(hint) = removed_syntax_hint(&content)
321+ return Err(ParseError {
1000− let text = written_line(node);
326+
1001− for d in &mut ctx.diagnostics[before..] {
327+ // @page [lang en, favicon /f.png, canonical URL, base URL] Title
1002− d.source_line.get_or_insert_with(|| text.as_str().into());
328+ if let Some(rest) = content.strip_prefix("@page ") {
329+ let rest = rest.trim_start();
330+ let title = if rest.starts_with('[') {
331+ let (attrs, title) = parse_attr_brackets_no_validate(rest, line_num, ctx)?;
333+ let value = attr.value.unwrap_or_default();
334+ match attr.key.as_str() {
335+ "lang" => ctx.lang = Some(value),
336+ "favicon" => ctx.favicon = Some(value),
337+ "canonical" => ctx.canonical = Some(value),
338+ "base" => ctx.base_url = Some(value),
339+ other => ctx.diagnostics.push(Diagnostic {
343+ "unknown @page attribute '{}' (expected lang, favicon, canonical or base)",
346+ severity: Severity::Warning,
347+ source_line: Some(content.clone()),
355+ ctx.page_title = Some(substitute_vars(title.trim(), &ctx.variables));
1005− for child in &node.children {
1006− check_unevaluated_node(child, ctx);
1010−/// Check the content passed to the calls of a line that was never
1011−/// evaluated: its `@slot NAME` blocks, and, for a function without
1012−/// `@children`, any other content.
1013−fn check_unevaluated_content(
1014− node: &syntax::Node,
1015− element: &syntax::ElementLine,
1016− ctx: &mut ParseContext,
1018− let calls: Vec<Option<(String, Rc<FnDef>)>> = element
1022− let function = ctx.defined_functions.get(&head.name)?;
1023− Some((head.name.clone(), function.clone()))
1026− check_fillers(node, element, &calls, ctx);
1027− let last = calls.len() - 1;
1028− for (i, call) in calls.iter().enumerate() {
1029− let Some((name, function)) = call else {
1032− if function.has_children || function.wraps_itself {
1035− let content = if i == last {
1036− element.text.is_some() || holds_content(&node.children, ctx)
1038− element.chain[i + 1].name != "slot" || !slot_is_built_in(ctx)
1041− let head = &element.chain[i];
1042− ctx.push_once(no_children(
1045− name_column(head, node.span.line),
1051−/// Check a head that was never evaluated: its name, and its attributes
360+ if let Some(rest) = content.strip_prefix("@let ") {
1052−/// (for a call, see [`check_call`]).
361+ let rest = rest.trim();
1053−fn check_head(head: &syntax::Head, line: usize, ctx: &mut ParseContext) {
362+
1054− let is_function =
363+ if !children.is_empty() {
1055− ctx.namespace.contains(&head.name) || ctx.defined_functions.contains_key(&head.name);
364+ return Err(ParseError {
1056− if is_function {
365+ line: line_num,
1057− ctx.used_functions.insert(head.name.clone());
366+ message: "@let with body requires a name".to_string(),
1058− if let Some(function) = ctx.defined_functions.get(&head.name).cloned()
367+ });
1059− && !function.wraps_itself
1061− check_call(head, &function, line, ctx);
1065− let kind = match parse_element_kind(&head.name, line, ctx) {
1068− ctx.diagnostics.push(e);
1072− if let Some(list) = &head.attrs {
1073− check_attrs(&list.attrs, line, ctx, &[]);
1074− // A word for laying out children on an element that doesn't lay
1075− // them out, as where the code runs (see `validate_tree`)
1076− if !kind.layout().is_container() && !has_no_element(&kind) {
1077− for attr in &list.attrs {
1078− let base = crate::vocab::base_attribute(&attr.key);
1080− && attr.choice.is_none()
1081− && attr.prefixed.is_none()
1082− && crate::vocab::CONTAINER_ATTRIBUTES.contains(&base)
1083− && !crate::vocab::split_prefixes(&attr.key)
1085− .contains(&"children:")
1087− ctx.push_once(not_a_container(&kind, line, base).column(attr.span.column));
1094−/// The attributes of a list that is never evaluated that can be checked
370+ if let Some((name, value)) = rest.split_once(' ') {
1095−/// together: not bundles or `if()`s. Names are checked; a value with a
371+ let value = value.trim();
1096−/// variable in it depends on what the variable holds, so only a literal
372+ // `@let name = EXPR` computes its value (see expr.rs); any
1097−/// value is (the other is checked as an empty value).
373+ // other value is literal text with `$var` interpolation.
1098−/// `@page`'s own rules (see `check_page_attr`) for a list that isn't
374+ if let Some(expression) = value.strip_prefix('=') {
1099−/// evaluated, as written: a value made from a variable counts as given.
375+ let value = ctx
1100−fn check_page_tokens(tokens: &[syntax::Attr], line: usize, ctx: &mut ParseContext) {
376+ .eval(expression.trim(), line_num)
1101− for token in tokens {
377+ .map(|v| v.to_string())
1102− match &token.choice {
378+ .unwrap_or_default();
1103− Some(choice) => {
379+ if name.starts_with("--") {
1104− for branch in &choice.branches {
380+ ctx.css_vars.push((name.to_string(), value.clone()));
1105− check_page_tokens(branch.attrs(), line, ctx);
381+ }
382+ ctx.variables.insert(name.to_string(), value);
383+ ctx.let_lines.entry(name.to_string()).or_insert(line_num);
387+ // Attribute bundle: @let name [attr1, attr2, ...]
388+ if value.starts_with('[') {
389+ let (attrs, _) = parse_attr_brackets(value, line_num, ctx)?;
390+ ctx.defines.insert(name.to_string(), attrs);
391+ ctx.define_lines.entry(name.to_string()).or_insert(line_num);
1108− // Under prefixes there are only styles
395+ // Triple quotes: @let name """...""" (syntax.rs joins the
1109− None if token.key.starts_with('$') || token.prefixed.is_some() => {}
396+ // lines of a multi-line string)
1110− None => {
397+ let value = if let Some(after_open) = value.strip_prefix("\"\"\"") {
1111− let value = token.value.as_deref().map(|v| v.trim_matches('"'));
398+ after_open.strip_suffix("\"\"\"").unwrap_or(after_open)
1112− let value = match value {
399+ } else if value.starts_with('"') && value.ends_with('"') && value.len() >= 2 {
1113− Some(v) if v.contains('$') => Some("$"),
400+ // Support quoted string interpolation: @let greeting "Hello $name"
1114− other => other,
401+ &value[1..value.len() - 1]
1116− check_page_attr(
405+ track_var_refs(value, &mut ctx.used_variables);
1117− &token.key,
406+ let value = substitute_vars(value, &ctx.variables);
1118− token.html,
407+ if name.starts_with("--") {
1119− value,
408+ // CSS custom property
1120− line,
409+ ctx.css_vars.push((name.to_string(), value.clone()));
1121− Some(token.span.column),
410+ }
1122− ctx,
411+ ctx.variables.insert(name.to_string(), value);
1123− );
412+ ctx.let_lines.entry(name.to_string()).or_insert(line_num);
1129−fn literal_attrs(tokens: &[syntax::Attr]) -> Vec<syntax::Attr> {
417+ // @meta NAME VALUE; `og:` names become Open Graph property tags
1130− // A prefixed group is checked with its prefixes, as far as its own
418+ if let Some(rest) = content.strip_prefix("@meta ") {
1131− // attributes can be; a prefixed bundle or `if()` depends on what it holds
419+ let rest = rest.trim();
1132− let group = |a: &syntax::Attr| {
420+ if let Some((name, value)) = rest.split_once(' ') {
1133− let prefixed = a.prefixed.as_ref()?;
421+ let value = substitute_vars(value.trim(), &ctx.variables);
1134− let syntax::Branch::Group { list, trailing } = &prefixed.target else {
422+ match name.trim().strip_prefix("og:") {
1135− return None;
423+ Some(property) => ctx.og_tags.push((property.to_string(), value)),
1136− };
424+ None => ctx.meta_tags.push((name.trim().to_string(), value)),
1137− let mut list = list.clone();
425+ }
1138− list.attrs = literal_attrs(&list.attrs);
1139− let mut a = a.clone();
1140− a.prefixed = Some(Box::new(syntax::Prefixed {
1141− target: syntax::Branch::Group {
1143− trailing: trailing.clone(),
1145− ..(**prefixed).clone()
1149− let groups = tokens.iter().filter_map(group);
1153− let bundle = a.key.starts_with('$') && a.value.is_none() && !a.html;
1154− a.choice.is_none() && a.prefixed.is_none() && !bundle
1157− let mut a = a.clone();
1158− let variable = |v: &String| v.contains('$');
1159− if !a.key.contains('$') && a.value.as_ref().is_some_and(variable) {
1160− a.value = Some(String::new());
1161− a.raw = format!("{} ", a.key);
1163− a
427+ return Ok(None);
1169−/// Check a call that was never evaluated: how it passes its parameters
1170−/// (none written `name=value`, and every one without a default passed,
1171−/// when no bundle or `if()` could pass it), and its other attributes, like
1172−/// those of an element.
1173−fn check_call(head: &syntax::Head, function: &FnDef, line: usize, ctx: &mut ParseContext) {
1174− let name = head.name.as_str();
1175− let attrs = head.attrs.as_ref().map_or(&[][..], |list| &list.attrs[..]);
1176− written_parameter_forms(name, function, attrs, line, ctx);
1177− if let Some(list) = &head.attrs {
1178− let params: Vec<String> = function.params.iter().map(|p| p.name.clone()).collect();
1179− check_attrs(&list.attrs, line, ctx, ¶ms);
1181− let unknown = attrs
1183− .any(|a| a.choice.is_some() || (a.key.starts_with('$') && a.value.is_none()));
1187− for param in function.params.iter().filter(|p| p.default.is_none()) {
1188− if !attrs.iter().any(|a| a.key == param.name) {
1189− let column = name_column(head, line);
1190− ctx.push_once(missing_parameter(name, ¶m.name, line, column));
1195−/// Report each parameter a call's list writes `name=value`, with the value
1196−/// as written and its column; returns their names, so the evaluated call
1197−/// doesn't report them again.
1198−fn written_parameter_forms(
1201− attrs: &[syntax::Attr],
1203− ctx: &mut ParseContext,
1205− let mut reported = Vec::new();
1206− for attr in attrs {
1207− if !(attr.html && function.is_param(&attr.key)) {
1210− let at = if attr.span.line == 0 {
1215− let value = attr.value.as_deref().unwrap_or("");
1216− let diagnostic = parameter_form(name, &attr.key, value, at).column(attr.span.column);
1217− ctx.push_once(match &ctx.current_source {
1218− (current, Some(text)) if *current == at => diagnostic.source(text.clone()),
1221− reported.push(attr.key.clone());
1226−fn check_inline_heads(text: &syntax::Text, line: usize, ctx: &mut ParseContext) {
431+ if content == "@head" || content.starts_with("@head ") {
1227− for segment in &text.segments {
432+ let trimmed = block_text(children).trim().to_string();
1228− if let Segment::Inline(inline) = segment {
433+ if !trimmed.is_empty() {
1229− check_head(&inline.head, line, ctx);
434+ ctx.head_blocks.push(trimmed);
1230− if let Some(text) = &inline.text {
1231− check_inline_heads(text, line, ctx);
1237−// ---------------------------------------------------------------------------
1239−// ---------------------------------------------------------------------------
1241−/// The `@else` lines that continue the `@if` or `@each` before `from`, and
439+ // --- @style block (raw CSS) ---
1242−/// the position after them.
440+ if content.trim() == "@style" {
1243−fn else_branches(block: &[syntax::Node], from: usize, is_if: bool) -> (Vec<&syntax::Node>, usize) {
441+ let trimmed = block_text(children).trim().to_string();
1244− let mut branches = Vec::new();
442+ if !trimmed.is_empty() {
1245− let mut next = from;
443+ ctx.custom_css.push(trimmed);
1246− let mut i = from;
444+ }
1247− while i < block.len() {
445+ return Ok(None);
1248− let node = &block[i];
1250− if node.is_trivia() {
1253− let condition = match node.directive().map(|d| &d.args) {
1254− Some(DirectiveArgs::Else { condition }) => condition.is_some(),
1257− if condition && !is_if {
1260− branches.push(node);
1269−impl Evaluator {
448+
1270− fn eval_block(&mut self, block: &[syntax::Node], ctx: &mut ParseContext) -> Vec<Node> {
449+ // --- @markdown block or file (convert markdown to HTML) ---
1271− let mut nodes = Vec::new();
450+ if content.trim() == "@markdown" || content.trim().starts_with("@markdown ") {
1272− let mut i = 0;
451+ let arg = content.trim().strip_prefix("@markdown").unwrap().trim();
1273− while i < block.len() {
452+ if arg.is_empty() {
1274− let node = &block[i];
453+ // Inline markdown block: indented children
1275− i += 1;
454+ let md_lines: Vec<String> = block_text(children).lines().map(String::from).collect();
1276− if node.is_trivia() {
455+ let html = markdown_to_html(&md_lines);
1277− continue;
456+ return Ok(Some(vec![Node::Raw(html)]));
1279− let result = match node.directive().map(|d| d.name()) {
458+ // External markdown file: @markdown file.md
1280− Some(name @ ("if" | "each")) => {
459+ let filename = substitute_vars(arg, &ctx.variables);
1281− let (branches, next) = else_branches(block, i, name == "if");
460+ let resolved = match &ctx.base_path {
1282− i = next;
461+ Some(base) => base.join(&filename),
1283− if name == "if" {
462+ None => PathBuf::from(&filename),
1284− Ok(Some(self.eval_if(node, &branches, ctx)))
463+ };
1285− } else {
464+ let md_text = if let Some(cached) = ctx.file_cache.get(&resolved) {
1286− self.eval_each(node, branches.first().copied(), ctx)
465+ cached.clone()
467+ match std::fs::read_to_string(&resolved) {
469+ ctx.file_cache.insert(resolved.clone(), text.clone());
473+ ctx.diagnostics.push(Diagnostic {
476+ message: format!("cannot read markdown '{}': {}", filename, e),
477+ severity: Severity::Error,
478+ source_line: Some(content.clone()),
1289− // Reported as a syntax error
484+ ctx.included_files.push(resolved);
1290− Some("else") => {
485+ let md_lines: Vec<String> = md_text.lines().map(|l| l.to_string()).collect();
1291− ctx.visited.insert(node.id);
486+ let html = markdown_to_html(&md_lines);
1292− Ok(None)
487+ return Ok(Some(vec![Node::Raw(html)]));
1294− _ => self.eval(node, ctx),
1297− Ok(Some(new_nodes)) => nodes.extend(new_nodes),
1299− // Record the error and go on, to report several in one pass
1302− .get_or_insert_with(|| node.source.as_str().into());
1303− ctx.diagnostics.push(e);
1310− /// Evaluate a block in its own scope: what it defines is visible to
1311− /// the end of the block, and not after it.
1312− fn eval_scoped(&mut self, block: &[syntax::Node], ctx: &mut ParseContext) -> Vec<Node> {
1314− let nodes = self.eval_block(block, ctx);
1319− /// `@if` with its `@else if` / `@else` branches. Every condition is
1320− /// checked (and its errors reported); the first that holds picks the
1324− node: &syntax::Node,
1325− branches: &[&syntax::Node],
1326− ctx: &mut ParseContext,
1328− let mut chosen = None;
1329− for branch in std::iter::once(node).chain(branches.iter().copied()) {
1330− ctx.visited.insert(branch.id);
1332− let holds = match branch.directive().map(|d| &d.args) {
1333− Some(DirectiveArgs::Condition(condition))
1334− | Some(DirectiveArgs::Else {
1335− condition: Some(condition),
1337− !condition.raw.is_empty()
1341− Some(condition.span.column),
1344− Some(DirectiveArgs::Else { condition: None }) => true,
1345− // A syntax error, already reported
1348− if holds && chosen.is_none() {
1349− chosen = Some(&branch.children);
1352− chosen.map_or_else(Vec::new, |body| self.eval_scoped(body, ctx))
1355− fn eval(
493+ if let Some(rest) = content.strip_prefix("@include ") {
1356− &mut self,
494+ let rest = rest.trim();
1357− node: &syntax::Node,
495+ if let Some((file, alias)) = rest.rsplit_once(" as ") {
1358− ctx: &mut ParseContext,
496+ return Err(ParseError {
1359− ) -> Result<Option<Vec<Node>>, ParseError> {
497+ line: line_num,
1360− ctx.visited.insert(node.id);
498+ message: format!(
1361− ctx.enter(node);
499+ "`@include ... as` was removed: write `@include {}` and drop the `{}.` \
1362− match &node.kind {
500+ prefix (run `htmlang upgrade`)",
1363− NodeKind::Blank | NodeKind::Comment => Ok(None),
501+ file.trim(),
1364− // `@code` and `@textarea` show their body as text; `@script`'s
502+ alias.trim()
1365− // goes into the page as it is
503+ ),
1366− NodeKind::Verbatim(body) if body.escaped => {
504+ });
1367− let text = body.text.trim_matches('\n').to_string();
1368− Ok(Some(vec![Node::Text(vec![TextSegment::Plain(text)])]))
1370− NodeKind::Verbatim(body) => Ok(Some(vec![Node::Raw(body.text.clone())])),
1371− NodeKind::Directive(directive) => {
1372− let mut nodes = self.eval_directive(node, directive, ctx)?;
1373− // A directive that takes no body: the lines indented under
1374− // it (a syntax error) are evaluated as its siblings. A
1375− // @let's body belongs to it even under a value (also an
1376− // error), so it is never evaluated in place.
1377− let takes_body = directive.spec.body != BodyKind::None;
1379− let siblings = self.eval_block(&node.children, ctx);
1380− nodes.get_or_insert_with(Vec::new).extend(siblings);
1384− NodeKind::Element(element) => self.eval_element(node, element, ctx).map(Some),
1385− NodeKind::Text(text) => {
1386− let mut nodes = vec![Node::Text(text_segments(text, ctx))];
1387− // Text takes no body: lines indented under it are its
1389− nodes.extend(self.eval_block(&node.children, ctx));
1392− }
506+ let filename = rest
1393− }
507+ .strip_prefix('"')
508+ .and_then(|f| f.strip_suffix('"'))
510+ let filename = substitute_vars(filename, &ctx.variables);
1395− fn eval_directive(
512+ // Glob support: if filename contains *, expand to multiple imports
1396− &mut self,
513+ if filename.contains('*') {
1397− node: &syntax::Node,
514+ let base_dir = match &ctx.base_path {
1398− directive: &syntax::Directive,
515+ Some(base) => base.clone(),
1399− ctx: &mut ParseContext,
516+ None => PathBuf::from("."),
1400− ) -> Result<Option<Vec<Node>>, ParseError> {
1401− let line_num = node.span.line;
1402− let content = &node.source;
1403− match (directive.name(), &directive.args) {
1404− // @page [lang=en, favicon /f.png, background #f8fafc] Title
1405− ("page", DirectiveArgs::Page { attrs, title }) => {
1406− let page = read_page(attrs.as_ref(), title.as_ref(), line_num, ctx);
1407− // A page has one root: a second `@page` (a layout called
1408− // twice, or one called after the page's own) is an error
1409− let here = match &ctx.current_file {
1410− Some(file) => format!("line {} of {}", line_num, file),
1411− None => format!("line {}", line_num),
1413− if let Some(first) = &ctx.page_at {
518+ let pattern_path = Path::new(&filename);
1414− let again = if *first == here {
519+ let (glob_dir, glob_pattern) = match pattern_path.parent() {
1415− "this @page runs a second time (in a loop, or in a function called \
520+ Some(dir) if !dir.as_os_str().is_empty() => (
1416− twice)"
521+ base_dir.join(dir),
1417− .to_string()
522+ pattern_path
1418− } else {
523+ .file_name()
1419− format!("a second @page (this page already has one, on {})", first)
524+ .unwrap_or_default()
1420− };
525+ .to_string_lossy()
1421− let diagnostic = Diagnostic::error(
526+ .to_string(),
1422− code::DUPLICATE_PAGE,
527+ ),
1423− line_num,
528+ _ => (base_dir.clone(), filename.clone()),
1425− "{}: a page has one @page, the root element that styles its <body>",
530+ let matched_files = match std::fs::read_dir(&glob_dir) {
1426− again
531+ Ok(entries) => {
1427− ),
532+ let mut files: Vec<PathBuf> = entries
1429− .source(content.clone())
534+ .filter(|e| {
1430− .subject("@page");
535+ let name = e.file_name().to_string_lossy().to_string();
1431− ctx.diagnostics.push(diagnostic);
536+ glob_match(&glob_pattern, &name)
1433− ctx.page_at = Some(here);
538+ .map(|e| e.path())
1434− ctx.page = Some(page);
539+ .collect();
1435− }
540+ files.sort();
1439− ("let", DirectiveArgs::Let(def)) => {
1440− let name = def.name.as_str();
1441− // Values, bundles and functions share one namespace: a
1442− // definition replaces whatever the name meant in its block
1444− LetForm::Function(function) => {
1445− self.define_function(name, &function.params, node, ctx);
1447− // `@let name = EXPR` computes its value (see expr.rs)
1448− LetForm::Computed(expression) => {
1450− .eval(&expression.raw, line_num, Some(expression.span.column))
1451− .unwrap_or_else(Value::empty);
1452− set_variable(name, value, line_num, ctx);
1454− // Attribute bundle: @let name [attr1, attr2, ...]
1455− LetForm::Bundle(list) => {
1456− ctx.in_bundle = true;
1457− let attrs = parse_attr_list(&list.attrs, line_num, ctx, true, &[]);
1458− ctx.in_bundle = false;
1459− ctx.env.define(name, Binding::Bundle(Rc::new(attrs)));
1460− ctx.define_lines.entry(name.to_string()).or_insert(line_num);
1462− // `@let size 16px`, `@let fruits apple, banana`,
1463− // `@let post $posts.0`: see `slot_value`
1464− LetForm::Value(value) => {
1466− ctx.slot_value(&value.raw, value.span.line, Some(value.span.column));
1467− set_variable(name, value, line_num, ctx);
1469− // Quoted text: `@let arrow "→ "`
543+ Err(e) => {
1470− LetForm::Quoted(value) => {
544+ ctx.diagnostics.push(Diagnostic {
1471− let raw = format!("\"{}\"", value.raw);
545+ line: line_num,
1472− let column = value.span.column.saturating_sub(1);
546+ column: None,
1473− let (text, quoted, _) =
547+ message: format!(
1474− ctx.fill_value(&raw, value.span.line, Some(column), Sink::Text);
548+ "cannot read directory for glob '{}': {}",
1475− let value = quoted.map_or(Value::Str(text), Value::Quoted);
549+ filename, e
1476− set_variable(name, value, line_num, ctx);
550+ ),
551+ severity: Severity::Error,
552+ source_line: Some(content.clone()),
557+ if matched_files.is_empty() {
558+ ctx.diagnostics.push(Diagnostic {
561+ message: format!("no files matched glob pattern '{}'", filename),
562+ severity: Severity::Warning,
563+ source_line: Some(content.clone()),
1479− Ok(None)
567+ let mut matched_nodes = Vec::new();
568+ for file_path in matched_files {
569+ let rel_name = file_path
570+ .strip_prefix(&base_dir)
571+ .unwrap_or(&file_path)
574+ let import_line = format!("@include \"{}\"", rel_name);
575+ matched_nodes.extend(self.eval_block(&syntax::parse(&import_line), ctx));
577+ return Ok(Some(matched_nodes));
1482− // @meta NAME VALUE; `og:` names become Open Graph property tags
580+ let resolved = match &ctx.base_path {
1483− ("meta", DirectiveArgs::Text(Some(arg))) => {
581+ Some(base) => base.join(&filename),
1484− let Some((name, value)) = arg.raw.split_once(char::is_whitespace) else {
582+ None => PathBuf::from(&filename),
1485− ctx.diagnostics.push(
583+ };
1486− Diagnostic::error(
584+
1487− code::MISSING_ARGUMENT,
585+ if ctx.include_stack.contains(&resolved) {
1488− line_num,
586+ let cycle_chain = format_include_chain(&ctx.include_stack);
1489− format!("@meta needs a name and a value: `@meta {} VALUE`", arg.raw),
587+ ctx.diagnostics.push(Diagnostic {
1490− )
588+ line: line_num,
1491− .source(content.clone()),
589+ column: None,
1492− );
590+ message: format!(
1493− return Ok(None);
591+ "circular include '{}' (cycle: {} → {})",
1494− };
592+ filename, cycle_chain, filename
1495− let value_column = arg.span.column + arg.raw.len() - value.trim_start().len();
593+ ),
1496− // An HTML attribute value: quoted text loses its quotes
594+ severity: Severity::Error,
1497− let (value, _, _) =
595+ source_line: Some(content.clone()),
1498− ctx.fill_value(value.trim(), line_num, Some(value_column), Sink::Text);
596+ });
1499− // The same tag twice says nothing more (a layout called
597+ return Ok(None);
1500− // twice): it is written once
1501− let (tags, tag) = match name.trim().strip_prefix("og:") {
1502− Some(property) => (&mut ctx.og_tags, (property.to_string(), value)),
1503− None => (&mut ctx.meta_tags, (name.trim().to_string(), value)),
1505− if !tags.contains(&tag) {
1508− ctx.head_at.get_or_insert(line_num);
1512− ("head", _) => {
600+ let imported_text = if let Some(cached) = ctx.file_cache.get(&resolved) {
1513− let text = verbatim_content(node);
601+ cached.clone()
1514− if !text.trim().is_empty() {
602+ } else {
1515− ctx.head_blocks.push(text.trim().to_string());
603+ match std::fs::read_to_string(&resolved) {
1516− ctx.head_at.get_or_insert(line_num);
604+ Ok(text) => {
605+ ctx.file_cache.insert(resolved.clone(), text.clone());
609+ ctx.diagnostics.push(Diagnostic {
612+ message: format!("cannot include '{}': {}", filename, e),
613+ severity: Severity::Error,
614+ source_line: Some(content.clone()),
621+ ctx.included_files.push(resolved.clone());
622+ ctx.include_stack.push(resolved.clone());
623+ let saved_base = ctx.base_path.clone();
624+ ctx.base_path = resolved.parent().map(|p| p.to_path_buf());
626+ let diag_count_before = ctx.diagnostics.len();
628+ let included_nodes = self.eval_block(&syntax::parse(&imported_text), ctx);
630+ // Annotate new diagnostics with import chain
631+ let import_chain = format_include_chain(&ctx.include_stack);
632+ for d in &mut ctx.diagnostics[diag_count_before..] {
633+ d.message = format!("{}\n in {}", d.message, import_chain);
1521− // @style: raw CSS
636+ ctx.base_path = saved_base;
1522− ("style", _) => {
637+ ctx.include_stack.pop();
1523− let text = verbatim_content(node);
638+ return Ok(Some(included_nodes));
1524− // Only the @style at the top of a function's body is
639+ }
1525− // scoped; anywhere else `&` is `:scope`, the whole page
640+
1526− if has_top_level_ampersand(&text) {
641+
1527− ctx.push_once(Diagnostic::warning(
642+
1528− code::INVALID_VALUE,
643+ // --- @data (load JSON file into variables) ---
1529− node.span.line,
644+
1530− "`&` in this @style is the whole page: only an @style at the top of a \
645+ // @data $name file.json values as $name.key
1531− function's body is scoped to the function, with `&` its root element"
646+ // @data $name dir/*.json a list of the files' records
1532− .to_string(),
647+ // @data $name [...] / {...} inline JSON
1533− ));
648+ // @data $name env:NAME [DEFAULT] an environment variable
1534− }
649+ if let Some(rest) = content.strip_prefix("@data ") {
1535− if !text.trim().is_empty() {
650+ let rest = rest.trim();
1536− ctx.custom_css.push(text.trim().to_string());
651+ let Some((prefix, filename)) = rest
653+ .and_then(|named| named.split_once(char::is_whitespace))
654+ .map(|(name, source)| (name.to_string(), source.trim().to_string()))
656+ return Err(ParseError {
659+ "@data needs a name: write `@data $name {}` and use `$name.key`",
660+ rest.trim_start_matches('$')
665+ if let Some(env) = filename.strip_prefix("env:") {
666+ let (var, default) = match env.split_once(char::is_whitespace) {
667+ Some((var, default)) => (var, Some(default.trim())),
668+ None => (env, None),
670+ let value = std::env::var(var)
672+ .or_else(|| default.map(|d| substitute_vars(d, &ctx.variables)));
673+ if value.is_none() {
674+ ctx.diagnostics.push(Diagnostic {
678+ "environment variable '{}' is not set and has no default",
681+ severity: Severity::Warning,
682+ source_line: Some(content.clone()),
1538− Ok(None)
685+ ctx.variables.insert(prefix, value.unwrap_or_default());
1541− // @markdown: an indented block, or a file
689+ // Inline JSON: @data $links [{"label": "Home", "url": "/"}]
1542− ("markdown", DirectiveArgs::Text(file)) => {
690+ let (json_text, source) = if filename.starts_with(['[', '{']) {
1543− let Some(file) = file else {
691+ (filename, "the inline data".to_string())
1544− let md_lines: Vec<String> = verbatim_text(&node.children)
692+ } else {
1545− .lines()
693+ let filename = substitute_vars(&filename, &ctx.variables);
1546− .map(String::from)
694+ if filename.contains('*') {
1547− .collect();
695+ self.load_data_glob(&prefix, &filename, line_num, &content, ctx);
1548− return Ok(Some(vec![Node::Raw(markdown_to_html(&md_lines))]));
696+ return Ok(None);
698+ let resolved = match &ctx.base_path {
699+ Some(base) => base.join(&filename),
700+ None => PathBuf::from(&filename),
1550− let filename = ctx.interpolate_text(&file.raw, line_num, Some(file.span.column));
702+ match std::fs::read_to_string(&resolved) {
1551− let resolved = ctx.resolve(&filename);
703+ Ok(text) => {
1552− let md_text = match ctx.read_file(&resolved) {
704+ ctx.included_files.push(resolved);
1553− Ok(text) => text,
705+ (text, format!("'{}'", filename))
1554 Err(e) => {
707 Err(e) => {
1555− ctx.diagnostics.push(
708+ ctx.diagnostics.push(Diagnostic {
1556− Diagnostic::error(
709+ line: line_num,
1557− code::UNREADABLE_FILE,
710+ column: None,
1558− line_num,
711+ message: format!("cannot load data '{}': {}", filename, e),
1559− format!("cannot read markdown '{}': {}", filename, e),
712+ severity: Severity::Error,
1560− )
713+ source_line: Some(content.clone()),
1561− .source(content.clone()),
714+ });
1563 return Ok(None);
715 return Ok(None);
1566− ctx.included_files.push(resolved);
718+ };
1567− let md_lines: Vec<String> = md_text.lines().map(|l| l.to_string()).collect();
719+ match parse_json_with_error(&json_text) {
1568− Ok(Some(vec![Node::Raw(markdown_to_html(&md_lines))]))
720+ Ok(json) => flatten_json(&prefix, &json, &mut ctx.variables),
721+ Err(detail) => ctx.diagnostics.push(Diagnostic {
724+ message: format!("invalid JSON in {}: {}", source, detail),
725+ severity: Severity::Error,
726+ source_line: Some(content.clone()),
1571− ("include", DirectiveArgs::Text(Some(path))) => {
732+ // --- @if / @else ---
1572− self.eval_include(node.id, path, line_num, content, ctx)
1575− ("data", DirectiveArgs::Data { name, source, .. }) => {
734+ if content.trim() == "@else" || content.trim().starts_with("@else if ") {
1576− self.eval_data(name, source, line_num, content, ctx);
735+ return Err(ParseError {
1577− Ok(None)
736+ line: line_num,
1578− }
737+ message: "@else without matching @if".to_string(),
1580− // @raw: the rest of its line, or its indented body, verbatim
741+ // --- @each loop ---
1582− let text = verbatim_content(node);
1583− let text = text.trim_end_matches('\n');
1584− Ok((!text.is_empty()).then(|| vec![Node::Raw(text.to_string())]))
1587− // A header with a syntax error (reported), or a directive
743+ // @raw: its indented body, or the rest of the line, verbatim
1588− // without its argument
744+ if content == "@raw" {
1589− _ => Ok(None),
745+ let text = block_text(children);
746+ let text = text.trim_end_matches('\n');
747+ return Ok((!text.is_empty()).then(|| vec![Node::Raw(text.to_string())]));
1591− }
749+ if let Some(rest) = content.strip_prefix("@raw ") {
1592−
750+ if rest.starts_with("\"\"\"") {
1593− fn eval_include(
751+ return Err(ParseError {
1594− &mut self,
752+ line: line_num,
1595− id: usize,
753+ message: "`@raw \"\"\"` was removed: put the content in an indented block \
1596− path: &syntax::Arg,
754+ under `@raw` (run `htmlang upgrade`)"
1597− line_num: usize,
755+ .to_string(),
1598− content: &str,
756+ });
1599− ctx: &mut ParseContext,
757+ }
1600− ) -> Result<Option<Vec<Node>>, ParseError> {
758+ return Ok(Some(vec![Node::Raw(rest.to_string())]));
1601− let (filename, column) = match path.raw.strip_prefix('"').and_then(|f| f.strip_suffix('"'))
1603− Some(quoted) => (quoted, path.span.column + 1),
1604− None => (path.raw.as_str(), path.span.column),
1606− let filename = ctx.interpolate_text(filename, line_num, Some(column));
1607− let resolved = ctx.resolve(&filename);
1609− if ctx.include_stack.contains(&resolved) {
1610− let cycle_chain = format_include_chain(&ctx.include_stack);
1611− ctx.diagnostics.push(
1613− code::CIRCULAR_INCLUDE,
1616− "circular include '{}' (cycle: {} → {})",
1617− filename, cycle_chain, filename
1625− let imported_text = match ctx.read_file(&resolved) {
761+ // --- Function call ---
1626− Ok(text) => text,
762+
1627− Err(e) => {
763+ if content.starts_with('@') {
1628− ctx.diagnostics.push(
764+ let name = extract_element_name(&content);
1629− Diagnostic::error(
765+ if ctx.functions.contains_key(name) {
1630− code::UNREADABLE_FILE,
766+ ctx.used_functions.insert(name.to_string());
1631− line_num,
767+ let nodes = self.expand_fn_call(name, &content, children, line_num, ctx)?;
1632− format!("cannot include '{}': {}", filename, e),
768+ return Ok(Some(nodes));
1640− ctx.included_files.push(resolved.clone());
772+ // --- Elements ---
1641− ctx.include_stack.push(resolved.clone());
773+
1642− let saved_base = ctx.base_path.clone();
774+ if content.starts_with('@') {
1643− ctx.base_path = resolved.parent().map(|p| p.to_path_buf());
775+ let node = self.parse_element_line(&content, children, line_num, ctx)?;
1644−
776+ return Ok(Some(vec![inline_svg(node, line_num, ctx)]));
1645− let diag_count_before = ctx.diagnostics.len();
1646− let import_chain = format_include_chain(&ctx.include_stack);
1647− let tree = ctx.parse_tree(&imported_text);
1648− ctx.diagnostics.extend(tree.diagnostics.iter().cloned());
1649− ctx.trees.push((tree.clone(), Some(import_chain.clone())));
1650− let files = Rc::make_mut(&mut ctx.included_by).entry(id).or_default();
1651− if !files.iter().any(|(_, chain)| *chain == import_chain) {
1652− files.push((tree.clone(), import_chain.clone()));
1654− let saved_file = ctx.current_file.replace(import_chain.clone());
778+
1655− let defined_before: HashSet<String> = ctx
779+ // --- Bare text ---
1657− .keys()
781+ // `[attrs]` alone on a line used to be an anonymous @el
1658− .chain(ctx.define_lines.keys())
782+ if let Some(list) = content.strip_prefix('[')
1659− .chain(ctx.fn_lines.keys())
783+ && (list.is_empty()
1660− .cloned()
784+ || list
1661− .collect();
785+ .split([',', ']'])
1662− let included_nodes = self.eval_block(&tree.nodes, ctx);
786+ .next()
1663− ctx.current_file = saved_file;
787+ .and_then(|first| first.split_whitespace().next())
1664− // An included file's definitions aren't reported unused here, where
788+ .is_some_and(crate::vocab::is_style_attribute))
1665− // their lines aren't this file's: a library's are there to be
789+ {
1666− // picked from, and any other file reports its own when checked
790+ ctx.diagnostics.push(Diagnostic {
1667− let keep = |name: &String, _: &mut usize| defined_before.contains(name);
791+ line: line_num,
1668− ctx.let_lines.retain(keep);
792+ column: None,
1669− ctx.define_lines.retain(keep);
793+ message: "a line starting with `[` is text: for an element, write `@el [...]` \
1670− ctx.fn_lines.retain(keep);
794+ (run `htmlang upgrade`)"
1672− // Annotate new diagnostics with import chain
796+ severity: Severity::Warning,
1673− for d in &mut ctx.diagnostics[diag_count_before..] {
797+ source_line: Some(content.clone()),
1674− d.message = format!("{}\n in {}", d.message, import_chain);
798+ });
1677− ctx.base_path = saved_base;
801+ let var_warnings =
1678− ctx.include_stack.pop();
802+ check_undefined_vars(&content, &ctx.variables, line_num, current_indent);
1679− Ok(Some(included_nodes))
803+ ctx.diagnostics.extend(var_warnings);
804+ track_var_refs(&content, &mut ctx.used_variables);
805+ let segments = parse_text_segments(&content, ctx);
806+ Ok(Some(vec![Node::Text(segments)]))
1682− /// @data $name file.json values as $name.key
809+ /// `@data $name dir/*.json`: a list with one record per matching file
1683− /// @data $name dir/*.json a list of the files' records
810+ /// (in name order), whose `file` is the file's name without extension.
1684− /// @data $name [...] / {...} inline JSON
811+ fn load_data_glob(
1685− /// @data $name env:NAME [DEFAULT] an environment variable
1687 &mut self,
812 &mut self,
1688− prefix: &str,
813+ name: &str,
1689− source: &syntax::Arg,
814+ pattern: &str,
1692− ctx: &mut ParseContext,
1694− let prefix = prefix.to_string();
1695− let filename = source.raw.as_str();
1696− if let Some(env) = filename.strip_prefix("env:") {
1697− let (var, default) = match env.split_once(char::is_whitespace) {
1698− Some((var, default)) => (var, Some(default.trim())),
1699− None => (env, None),
1701− let default_column = default.map(|d| source.span.column + filename.len() - d.len());
1702− let value = std::env::var(var)
1704− .or_else(|| default.map(|d| ctx.interpolate_text(d, line_num, default_column)));
1705− if value.is_none() {
1706− ctx.diagnostics.push(
1707− Diagnostic::warning(
1708− code::UNSET_ENVIRONMENT,
1711− "environment variable '{}' is not set and has no default",
1718− ctx.bind(&prefix, Value::Str(value.unwrap_or_default()));
1722− // Inline JSON: @data $links [{"label": "Home", "url": "/"}]
1723− let (json_text, source) = if filename.starts_with(['[', '{']) {
1724− (filename.to_string(), "the inline data".to_string())
1726− let filename = ctx.interpolate_text(filename, line_num, Some(source.span.column));
1727− if filename.contains('*') {
1728− self.load_data_glob(&prefix, &filename, line_num, content, ctx);
1731− let resolved = ctx.resolve(&filename);
1732− match std::fs::read_to_string(&resolved) {
1734− ctx.included_files.push(resolved);
1735− (text, format!("'{}'", filename))
1738− ctx.diagnostics.push(
1740− code::UNREADABLE_FILE,
1742− format!("cannot load data '{}': {}", filename, e),
1750− match parse_json_with_error(&json_text) {
1751− Ok(json) => ctx.bind(&prefix, json_value(json)),
1752− Err(detail) => ctx.diagnostics.push(
1754− code::INVALID_JSON,
1756− format!("invalid JSON in {}: {}", source, detail),
1763− /// `@data $name dir/*.json`: a list with one record per matching file
1764− /// (in name order), whose `file` is the file's name without extension.
1769 line_num: usize,
815 line_num: usize,
1770 content: &str,
816 content: &str,
1771 ctx: &mut ParseContext,
817 ctx: &mut ParseContext,
@@ -1791,15 +837,13 @@ impl Evaluator {
1792 .collect(),
838 .collect(),
1793 Err(e) => {
839 Err(e) => {
1794− ctx.diagnostics.push(
840+ ctx.diagnostics.push(Diagnostic {
1795− Diagnostic::new(
841+ line: line_num,
1796− code::UNREADABLE_FILE,
842+ column: None,
1797− Severity::Error,
843+ message: format!("cannot read directory for '{}': {}", pattern, e),
1798− line_num,
844+ severity: Severity::Error,
1799− format!("cannot read directory for '{}': {}", pattern, e),
845+ source_line: Some(content.to_string()),
1801− .source(content.to_string()),
@@ -1814,15 +858,13 @@ impl Evaluator {
1814 let text = match std::fs::read_to_string(&file) {
858 let text = match std::fs::read_to_string(&file) {
1815 Ok(text) => text,
859 Ok(text) => text,
1816 Err(e) => {
860 Err(e) => {
1817− ctx.diagnostics.push(
861+ ctx.diagnostics.push(Diagnostic {
1818− Diagnostic::new(
862+ line: line_num,
1819− code::UNREADABLE_FILE,
863+ column: None,
1820− Severity::Error,
864+ message: format!("cannot load data '{}': {}", file.display(), e),
1821− line_num,
865+ severity: Severity::Error,
1822− format!("cannot load data '{}': {}", file.display(), e),
866+ source_line: Some(content.to_string()),
1824− .source(content.to_string()),
1826 continue;
868 continue;
@@ -1833,435 +875,257 @@ impl Evaluator {
1834 records.push(JsonValue::Object(pairs));
876 records.push(JsonValue::Object(pairs));
1836− Ok(_) => ctx.diagnostics.push(
878+ Ok(_) => ctx.diagnostics.push(Diagnostic {
1837− Diagnostic::new(
879+ line: line_num,
1838− code::INVALID_JSON,
880+ column: None,
1839− Severity::Error,
881+ message: format!("'{}' should hold a JSON object", file.display()),
1840− line_num,
882+ severity: Severity::Error,
1841− format!("'{}' should hold a JSON object", file.display()),
883+ source_line: Some(content.to_string()),
1843− .source(content.to_string()),
885+ Err(detail) => ctx.diagnostics.push(Diagnostic {
1844− ),
886+ line: line_num,
1845− Err(detail) => ctx.diagnostics.push(
887+ column: None,
1846− Diagnostic::new(
888+ message: format!("invalid JSON in '{}': {}", file.display(), detail),
1847− code::INVALID_JSON,
889+ severity: Severity::Error,
1848− Severity::Error,
890+ source_line: Some(content.to_string()),
1850− format!("invalid JSON in '{}': {}", file.display(), detail),
1852− .source(content.to_string()),
1855 ctx.included_files.push(file);
893 ctx.included_files.push(file);
1857− ctx.bind(name, json_value(JsonValue::Array(records)));
895+ flatten_json(name, &JsonValue::Array(records), &mut ctx.variables);
1860− /// `@each $item in LIST` or `@each $item, $index in LIST`, with the
898+ /// `@each $item in LIST` or `@each $item, $index in LIST`. A LIST from
1861− /// `@else` that follows it. LIST is a value (see
899+ /// JSON binds each record or value to `$item`; any other list is text,
1862− /// [`ParseContext::slot_value`]): a list written with commas, a range,
900+ /// split on commas, or a range `A..B [step N]`.
1863− /// or one `$name` or `${...}` that holds a list. Each item is bound
1864− /// whole to `$item`, and each iteration is a block of its own.
1865 fn eval_each(
901 fn eval_each(
1866 &mut self,
902 &mut self,
1867− node: &syntax::Node,
903+ header: &str,
1868− empty_branch: Option<&syntax::Node>,
904+ body: &[Syntax],
1869 ctx: &mut ParseContext,
907 ctx: &mut ParseContext,
1870− ) -> Result<Option<Vec<Node>>, ParseError> {
908+ ) -> Result<Vec<Node>, ParseError> {
1871− ctx.visited.insert(node.id);
909+ let Some((names, list_src)) = header.split_once(" in ") else {
1872− if let Some(branch) = empty_branch {
910+ return Err(ParseError {
1873− ctx.visited.insert(branch.id);
911+ line: line_num,
1874− }
912+ message: "@each requires: @each $item in LIST".to_string(),
1875− ctx.enter(node);
913+ });
1876− // A malformed header is a syntax error, already reported
1877− let Some(DirectiveArgs::Each(header)) = node.directive().map(|d| &d.args) else {
1880− let body = &node.children;
1881− let empty: &[syntax::Node] = empty_branch.map_or(&[], |b| &b.children);
1882− let (item, index) = (header.item.as_str(), header.index.as_deref());
1883− let list = &header.list;
1884− // `[...]` is an attribute list or JSON elsewhere, not a list here
1885− let bracketed = list.raw.starts_with('[') && list.raw.ends_with(']');
1886− let (source, filled) = match bracketed {
1887− true => (Value::empty(), false),
1888− false => ctx.slot_value(&list.raw, list.span.line, Some(list.span.column)),
1890− let not_a_list = |message: String, ctx: &ParseContext| {
1891− let diagnostic = Diagnostic::error(code::INVALID_LOOP, list.span.line, message)
1892− .column(list.span.column)
1893− .subject(list.raw.as_str());
1894− match &ctx.current_source {
1895− (current, Some(text)) if *current == list.span.line => {
1896− diagnostic.source(text.clone())
1901− if bracketed {
915+ let names: Vec<&str> = names.split(',').map(|v| v.trim().trim_start_matches('$')).collect();
1902− let inner = list.raw[1..list.raw.len() - 1].trim().to_string();
916+ if names.len() > 2 {
1903− let diagnostic = not_a_list(
917+ return Err(ParseError {
1904− format!(
918+ line: line_num,
1905− "@each takes a list written without brackets, `@each ${} in {}`; \
919+ message: "@each takes `$item` or `$item, $index`: to loop over records, \
1906− JSON data goes in `@data`",
920+ load them with @data and use `$item.key`"
1907− item, inner
921+ .to_string(),
1911− .suggest(Some(inner));
1912− ctx.push_once(diagnostic);
1914− let items: Vec<Value> = match source {
924+ let (item, index) = (names[0], names.get(1).copied());
1915− Value::List(list) => list.items.to_vec(),
925+ let list_src = list_src.trim();
1916− // Reported (an undefined `$name`, brackets): there is nothing
926+ if list_src.ends_with(']') && list_src.contains("[page ") {
1917− // to repeat
927+ return Err(ParseError {
1918− _ if !filled => Vec::new(),
928+ line: line_num,
1919− Value::Record(_) => {
929+ message: "@each pagination (`[page N]`) was removed: split the list or \
1920− let diagnostic = not_a_list(
930+ filter it with @if"
1921− format!(
931+ .to_string(),
1922− "@each repeats for the items of a list, and `{}` is a record: \
932+ });
1923− loop over a list of records, or use its fields",
933+ }
1924− list.raw
934+ track_var_refs(list_src, &mut ctx.used_variables);
1926− ctx,
936+ // A list loaded from JSON, by name
1927− );
937+ let data_list = list_src.strip_prefix('$').and_then(|name| {
1928− ctx.push_once(diagnostic);
938+ let len = ctx.variables.get(&format!("{}#", name))?.parse::<usize>().ok()?;
939+ Some((name.to_string(), len))
941+ let undefined = list_src.strip_prefix('$').filter(|name| {
942+ name.chars().all(|c| c.is_alphanumeric() || matches!(c, '_' | '-' | '.'))
943+ && !ctx.variables.contains_key(*name)
945+ let text_items: Vec<String> = match (&data_list, undefined) {
946+ (Some(_), _) => Vec::new(),
947+ // A missing variable is an empty list: quietly for a record's
948+ // missing field (`$post.tags`), with a warning otherwise
949+ (None, Some(name)) => {
950+ let root = name.split('.').next().unwrap_or(name);
951+ if !ctx.variables.contains_key(root) {
952+ ctx.diagnostics.push(Diagnostic {
955+ message: format!("undefined variable '${}'", name),
956+ severity: Severity::Warning,
957+ source_line: Some(format!("@each {}", header)),
1929 Vec::new()
960 Vec::new()
1931− // Empty text (a field a record doesn't have) is no items; any
962+ (None, None) => text_list_items(&substitute_vars(list_src, &ctx.variables)),
1932− // other value is one
1933− value if value.to_string().is_empty() => Vec::new(),
1934− value => vec![value],
964+ let count = data_list.as_ref().map_or(text_items.len(), |(_, len)| *len);
1937− if body.iter().all(syntax::Node::is_trivia) {
966+ if body.is_empty() {
1938− return Ok(Some(Vec::new()));
967+ return Ok(Vec::new());
1940− if items.is_empty() {
969+ if count == 0 {
1941− return Ok(Some(self.eval_scoped(empty, ctx)));
970+ return Ok(self.eval_scoped(empty, ctx));
972+ let saved_vars = ctx.variables.clone();
1943 let mut nodes = Vec::new();
973 let mut nodes = Vec::new();
1944− for (i, value) in items.into_iter().enumerate() {
974+ for i in 0..count {
1945− ctx.env.push();
975+ match &data_list {
1946− ctx.bind(item, value);
976+ Some((name, _)) => bind_item(&mut ctx.variables, &format!("{}.{}", name, i), item),
978+ let text = text_items.get(i).cloned().unwrap_or_default();
979+ ctx.variables.insert(item.to_string(), text);
1947 if let Some(index) = index {
982 if let Some(index) = index {
1948− ctx.bind(index, Value::Num(i as f64));
983+ ctx.variables.insert(index.to_string(), i.to_string());
1950 nodes.extend(self.eval_block(body, ctx));
985 nodes.extend(self.eval_block(body, ctx));
1953− Ok(Some(nodes))
987+ ctx.variables = saved_vars;
1956 fn define_function(
991 fn define_function(
1957 &mut self,
992 &mut self,
1958 name: &str,
993 name: &str,
1959− params: &[syntax::Param],
994+ params: &[String],
1960− node: &syntax::Node,
995+ defaults: &HashMap<String, String>,
1961 ctx: &mut ParseContext,
998 ctx: &mut ParseContext,
1963− let line_num = node.span.line;
1964− let body = &node.children;
1965 // An @style block at the top of the body is scoped to the
1000 // An @style block at the top of the body is scoped to the
1966− // function: its rules apply inside a `.hl-fn-NAME-HASH` wrapper (a
1001+ // function: its rules apply inside a `.hl-NAME` wrapper.
1967− // generated class never has a second `-`, so the two can't meet).
1002+ let (style, body): (Vec<&Syntax>, Vec<&Syntax>) = body
1968− // The hash is the stylesheet's, so two functions of one name with
1003+ .iter()
1969− // two stylesheets, in two files, don't style each other's elements
1004+ .partition(|node| matches!(node, Syntax::Line { text, .. } if text == "@style"));
1970− // in a page that has both. It is written into the page when the
1005+ if !style.is_empty() {
1971− // function is called.
1972− let (style, body): (Vec<&syntax::Node>, Vec<&syntax::Node>) =
1973− body.iter().partition(|node| node.is_directive("style"));
1974− let scoped = (!style.is_empty()).then(|| {
1975 let css: String = style
1006 let css: String = style
1977− .map(|node| {
1008+ .filter_map(|node| match node {
1978− ctx.visited.insert(node.id);
1009+ Syntax::Line { children, .. } => Some(block_text(children)),
1979− verbatim_content(node)
1010+ _ => None,
1981 .collect();
1012 .collect();
1982− let digits = crate::codegen::CLASS_DIGITS;
1983− let hash = crate::codegen::hash_digits(crate::codegen::stable_hash(&css), digits);
1984− let class = format!("hl-fn-{}-{}", name, hash);
1985 // Nested under the scope class, so any CSS works (multi-line
1013 // Nested under the scope class, so any CSS works (multi-line
1986 // rules, at-rules)
1014 // rules, at-rules)
1987− let css = if css.trim().is_empty() {
1015+ if !css.trim().is_empty() {
1988− String::new()
1016+ ctx.custom_css.push(format!(".hl-{} {{\n{}}}", name, css));
1990− format!(".{} {{\n{}}}", class, css)
1018+ ctx.scoped_functions.insert(name.to_string());
1995− // A default is filled in only when a call leaves its parameter
1996− // out, so the names in it count as used here
1997− for default in params.iter().filter_map(|p| p.default.as_ref()) {
1998− track_var_refs(default, &mut ctx.used_variables);
2000 ctx.fn_lines.entry(name.to_string()).or_insert(line_num);
1021 ctx.fn_lines.entry(name.to_string()).or_insert(line_num);
2001− let wraps_itself = ElementKind::from_name(name).is_some()
1022+ ctx.functions.insert(
2002− && body.iter().any(|node| calls_unguarded(node, name));
1023+ name.to_string(),
2003− if wraps_itself {
1024+ FnDef {
2004− ctx.push_once(
1025+ params: params.to_vec(),
2005− Diagnostic::error(
1026+ defaults: defaults.clone(),
2006− code::RECURSIVE_CALL,
1027+ body: body.into_iter().cloned().collect(),
2009− "@{0} in the body of `@let @{0}` calls the function itself, not the \
2010− element @{0}, so it would never stop: give the function another name \
2011− (such as @site-{0})",
2018− for node in &body {
2019− node.walk(&mut |node| {
2020− if let Some(d) = marker_in_text(node) {
2025− let body: Vec<syntax::Node> = body.into_iter().cloned().collect();
2026− let (slots, has_children) = declared_slots(&body, ctx);
2027− let function = Rc::new(FnDef {
2028− params: params.to_vec(),
2030− source: ctx.current_source.1.clone(),
2033− file: ctx.current_file.clone(),
2037− env: ctx.env.clone(),
2040− ctx.defined_functions
2041− .insert(name.to_string(), function.clone());
2042− ctx.env.define(name, Binding::Function(function));
2045− /// An element line: a chain of elements and function calls, the last of
1032+ fn expand_fn_call(
2046− /// which gets the indented children.
2048 &mut self,
1033 &mut self,
2049− node: &syntax::Node,
1034+ name: &str,
2050− element: &syntax::ElementLine,
1035+ content: &str,
1036+ children: &[Syntax],
2051 ctx: &mut ParseContext,
1038 ctx: &mut ParseContext,
2052 ) -> Result<Vec<Node>, ParseError> {
1039 ) -> Result<Vec<Node>, ParseError> {
2053− // An unclosed attribute list is a syntax error, already reported
1040+ // Recursive function cycle detection
2054− if element
1041+ if ctx.fn_call_stack.contains(&name.to_string()) {
2055− .chain
1042+ return Err(ParseError {
2056− .iter()
1043+ line: line_num,
2057− .any(|h| h.attrs.as_ref().is_some_and(|a| !a.closed))
1044+ message: format!(
2058− {
1045+ "recursive function call to @{} (call stack: {})",
2059− return Ok(Vec::new());
1046+ name,
2060− }
1047+ ctx.fn_call_stack.join(" -> ")
2061− let line_num = node.span.line;
1048+ ),
2062− let last = element.chain.len() - 1;
1049+ });
2063− // Each head is read where it is written, left to right. The
2064− // children belong to the last one, so the chain is built right to
2065− // left, each link wrapping the next.
2066− let mut links = Vec::new();
2067− for (i, head) in element.chain.iter().enumerate() {
2068− let text = if i == last {
2069− element.text.as_ref()
2073− links.push(resolve(head, text, line_num, &node.source, ctx)?);
2075− let calls: Vec<Option<(String, Rc<FnDef>)>> = links
2077− .map(|link| match link {
2078− Resolved::Call(call) => Some((call.name.clone(), call.function.clone())),
2079− Resolved::Element(_) => None,
2082− let mut current = self.eval_scoped(&node.children, ctx);
2083− // After the lines under the call ran, so the files they include
2085− check_fillers(node, element, &calls, ctx);
2086− for link in links.into_iter().rev() {
2087− current = self.complete(link, current, ctx)?;
2089− Ok(current)
1051+ ctx.fn_call_stack.push(name.to_string());
2092− /// Give a resolved `@name` its children: an element holds them, and a
1053+ // Parse [param value, ...] arguments
2093− /// function's body puts them where its `@children` is.
1054+ let rest = &content[1 + name.len()..];
2094− fn complete(
1055+ let rest = rest.trim_start();
2096− resolved: Resolved,
1057+ let (args, trailing_text) = if rest.starts_with('[') {
2097− children: Vec<Node>,
1058+ parse_attr_brackets_no_validate(rest, line_num, ctx)?
2098− ctx: &mut ParseContext,
1059+ } else {
2099− ) -> Result<Vec<Node>, ParseError> {
1060+ (Vec::new(), rest.to_string())
2100− match resolved {
1061+ };
2101− Resolved::Element(mut element) => {
1062+
2102− element.children.extend(children);
1063+ // Clone function definition (releases borrow on ctx). If the function is
2103− let line = element.line_num;
1064+ // missing (shouldn't normally happen — callers check ctx.functions.contains_key
2104− Ok(vec![inline_svg(Node::Element(element), line, ctx)])
1065+ // first — but we avoid panicking on malformed state).
1066+ let fn_def = match ctx.functions.get(name) {
1067+ Some(def) => def.clone(),
1069+ ctx.fn_call_stack.pop();
1070+ return Err(ParseError {
1072+ message: format!("undefined function @{}", name),
2106− Resolved::Call(call) => self.expand_fn_call(*call, children, ctx),
1075+ };
2110− fn expand_fn_call(
1077+ // Parse caller's children, separating named slots from default children
2111− &mut self,
1078+ let all_caller_children = self.eval_block(children, ctx);
2113− all_caller_children: Vec<Node>,
2114− ctx: &mut ParseContext,
2115− ) -> Result<Vec<Node>, ParseError> {
2121− text: trailing_text,
2128− let (name, content) = (name.as_str(), content.as_str());
2130− // Separate the caller's `@slot NAME` blocks from its other
2131− // children. A block for a slot the function doesn't declare was
2132− // reported where it is written (see `check_fillers`), like one
2134 let mut slot_contents: HashMap<String, Vec<Node>> = HashMap::new();
1079 let mut slot_contents: HashMap<String, Vec<Node>> = HashMap::new();
2135 let mut caller_children = Vec::new();
1080 let mut caller_children = Vec::new();
2136 for child in all_caller_children {
1081 for child in all_caller_children {
2137− if let Node::Element(elem) = child {
1082+ if let Node::Element(ref elem) = child
2138− match elem.kind {
1083+ && let ElementKind::Slot(ref slot_name) = elem.kind
2139− ElementKind::Slot(slot_name) => {
1084+ && !slot_name.is_empty()
2140− slot_contents
1085+ {
2141− .entry(slot_name)
1086+ slot_contents
2142− .or_default()
1087+ .entry(slot_name.clone())
2143− .extend(elem.children);
1088+ .or_default()
2144− }
1089+ .extend(elem.children.clone());
2145− kind => caller_children.push(Node::Element(Element { kind, ..elem })),
2147 continue;
1090 continue;
2149 caller_children.push(child);
1092 caller_children.push(child);
2151− // Text after the call, as in `@card [color red] New`, is content:
1094+ // Text after the call, as in `@badge [color red] New`, is content:
2152− // it goes first among the caller's children, and like them it is
1095+ // it goes first among the caller's children.
2153− // evaluated where the call is written.
1096+ let trailing_text = trailing_text.trim();
2154− if let Some(text) = &trailing_text {
1097+ if !trailing_text.is_empty() {
2155− caller_children.insert(0, Node::Text(text_segments(text, ctx)));
1098+ caller_children.insert(0, Node::Text(parse_text_segments(trailing_text, ctx)));
2157− // Content goes where the body's `@children` is: without one, it
2158− // would be dropped
2159− if !fn_def.has_children && !caller_children.is_empty() {
2160− let (column, text) = match &name_at {
2161− Some((column, text)) => (Some(*column), text.as_str()),
2162− None => (None, content),
2164− ctx.push_once(no_children(name, line_num, column).source(text));
2167− if fn_def.wraps_itself {
2168− return Ok(Vec::new());
2170− // Only the body is inside the call, so a function may appear in the
2171− // content its caller passes it. A function may call itself, under
2172− // a condition that stops it; one that doesn't stop goes too deep.
2174− return Ok(Vec::new());
2176− if ctx.fn_call_stack.len() >= MAX_CALL_DEPTH {
2177− ctx.too_deep = true;
2178− return Err(too_deep(name, &ctx.fn_call_stack, line_num).source(content));
2182− ctx.current_source.clone(),
2185− ctx.fn_call_stack.push(name.to_string());
2187− // The body runs where the function is defined: it sees what was
1101+ // Save variable state, inject function parameters
2188− // visible there, the function itself (so it can call itself), and
1102+ let saved_vars = ctx.variables.clone();
2189− // its parameters, bound by name in the order they are declared. A
2190− // default is filled in at the call, seeing the same, with the
2191− // parameters before it.
2192− let caller_env = std::mem::replace(&mut ctx.env, fn_def.env.clone());
2194− ctx.env.define(name, Binding::Function(fn_def.clone()));
2195 let mut consumed = vec![false; args.len()];
1103 let mut consumed = vec![false; args.len()];
2196− for param in &fn_def.params {
1104+ for (i, param) in fn_def.params.iter().enumerate() {
2197− let mut passed = None;
1105+ let named = args.iter().position(|a| a.key == *param);
2198− for (j, arg) in args.iter().enumerate() {
1106+ // Positional fallback, unless that argument is named for a
2199− if arg.key != param.name {
1107+ // different parameter.
2200− continue;
1108+ let positional = args
1110+ .filter(|a| !fn_def.params.contains(&a.key) && a.value.is_some())
1113+ .filter(|&j| args[j].value.is_some())
1116+ consumed[j] = true;
1117+ args[j].value.clone()
1119+ .or_else(|| fn_def.defaults.get(param).cloned())
1120+ .unwrap_or_default();
1121+ if let Some(j) = named {
2202 consumed[j] = true;
1122 consumed[j] = true;
2203− // The later one wins, as for any attribute: one written
2204− // after a bundle overrides it, and only one written twice
2205− // in the call's own list is reported
2206− if passed.is_some() && written_keys.iter().filter(|k| **k == param.name).count() > 1
2209− Diagnostic::warning(
2210− code::DUPLICATE_ATTRIBUTE,
2213− "parameter '{}' of @{} is passed twice: the later one wins",
2218− .subject(param.name.as_str()),
2221− // Written `name=value` in the call's own list is reported
2222− // as written; this is one from a bundle
2223− if arg.html && !written_form.contains(&arg.key) {
2224− let value = arg.value.as_deref().unwrap_or("");
2225− ctx.push_once(parameter_form(name, &arg.key, value, line_num).source(content));
2229− let value = match passed {
1124+ ctx.variables.insert(param.clone(), value);
2230− // A parameter's name alone is true: `@post-card [featured]`
2231− Some(j) if args[j].value.is_none() => Value::Bool(true),
2232− // What the call passed, with its type: a record, a list,
2234− Some(j) => values[j].clone().unwrap_or_else(|| {
2235− let arg = &args[j];
2236− match &arg.quoted {
2237− Some(quoted) => Value::Quoted(quoted.clone()),
2238− None => Value::Str(arg.value.clone().unwrap_or_default()),
2241− None => match ¶m.default {
2243− let before = ctx.diagnostics.len();
2244− let value = fill_default(&fn_def, param, default, ctx);
2245− point_at_call(ctx, before, &fn_def, name, line_num, content);
2249− let (column, text) = match &name_at {
2250− Some((column, text)) => (Some(*column), text.as_str()),
2251− None => (None, content),
2254− missing_parameter(name, ¶m.name, line_num, column).source(text),
2260− ctx.bind(¶m.name, value);
2262 // Arguments that aren't parameters are attributes for the
1126 // Arguments that aren't parameters are attributes for the
2263 // function's root element, so a function can be styled like an
1127 // function's root element, so a function can be styled like an
2264− // element: `@card [background red] New`.
1128+ // element: `@badge [background red] New`.
2265 let forwarded: Vec<Attribute> = args
1129 let forwarded: Vec<Attribute> = args
2267 .zip(&consumed)
1131 .zip(&consumed)
@@ -2269,1435 +1133,221 @@ impl Evaluator {
2269 .map(|(a, _)| a.clone())
1133 .map(|(a, _)| a.clone())
2270 .collect();
1134 .collect();
2272− // Evaluate the body with the parameters in scope, as lines of the
1136+ // Evaluate the body with the parameters in scope
2273− // file that defines the function
1137+ let body_nodes = self.eval_block(&fn_def.body, ctx);
2274− let caller_file = std::mem::replace(&mut ctx.current_file, fn_def.file.clone());
2275− let before = ctx.diagnostics.len();
2276− let mut body_nodes = self.eval_block(&fn_def.body, ctx);
2277− ctx.current_file = caller_file;
2278− point_at_call(ctx, before, &fn_def, name, line_num, content);
2280− // Back to the caller's names and call stack
1139+ // Restore variables and call stack
2281− ctx.env = caller_env;
1140+ ctx.variables = saved_vars;
2282 ctx.fn_call_stack.pop();
1141 ctx.fn_call_stack.pop();
2283− if ctx.fn_call_stack.is_empty() {
2284− ctx.too_deep = false;
2286− (ctx.current_line, ctx.current_source, ctx.current_node) = caller;
2288− // What the body wrote is the call's
2289− belongs_to_call(&mut body_nodes, name, line_num);
2291 // Replace @children with caller's children and @slot with slot content
1143 // Replace @children with caller's children and @slot with slot content
2292 let mut result_nodes =
1144 let mut result_nodes =
2293 replace_children_and_slots(body_nodes, &caller_children, &slot_contents);
1145 replace_children_and_slots(body_nodes, &caller_children, &slot_contents);
2295− // Attributes that aren't parameters style the function's root
1147+ if !forwarded.is_empty() {
2296− // element, and a scoped @style's class goes on it too.
2297− let scope_class = fn_def.scoped.as_ref().map(|(class, _)| class.clone());
2298− if !forwarded.is_empty() || scope_class.is_some() {
2299 let mut roots = result_nodes.iter_mut().filter_map(|n| match n {
1148 let mut roots = result_nodes.iter_mut().filter_map(|n| match n {
2300 Node::Element(e) => Some(e),
1149 Node::Element(e) => Some(e),
2301 _ => None,
1150 _ => None,
2303− let root = match (roots.next(), roots.next()) {
1152+ match (roots.next(), roots.next()) {
2304− (Some(root), None) => Some(root),
1153+ (Some(root), None) => root.attrs.extend(forwarded),
2305− _ => None,
1154+ _ => ctx.diagnostics.push(Diagnostic {
2306− };
1155+ line: line_num,
2307− let mut problems = Vec::new();
1156+ column: None,
2308− match root {
1157+ message: format!(
2309− Some(root) => {
1158+ "attributes {} on @{} are not parameters, and its body has no single \
2310− // A call's `class=` adds to the root's own classes
1159+ root element to receive them",
2311− for attr in forwarded {
1160+ forwarded
2312− let existing = (attr.html && attr.key == "class")
1161+ .iter()
2313− .then(|| root.attrs.iter_mut().find(|a| a.html && a.key == "class"))
1162+ .map(|a| format!("'{}'", a.key))
2314− .flatten();
1163+ .collect::<Vec<_>>()
2315− match existing {
1164+ .join(", "),
2316− Some(class) => {
1165+ name
2317− let mut value = class.value.take().unwrap_or_default();
1166+ ),
2318− for name in attr.value.as_deref().unwrap_or("").split_whitespace() {
1167+ severity: Severity::Warning,
2319− if !value.split_whitespace().any(|c| c == name) {
1168+ source_line: Some(content.to_string()),
2320− value.push(' ');
1169+ }),
2321− value.push_str(name);
2324− class.value = Some(value.trim().to_string());
2326− None => root.attrs.push(attr),
2329− // The scoped `@style` goes into the page once, when the
2330− // function is first called
2331− if let Some((_, css)) = &fn_def.scoped
2333− && !ctx.scoped_css.contains(css)
2335− ctx.scoped_css.push(css.clone());
2337− if let Some(class) = scope_class {
2338− match root.attrs.iter_mut().find(|a| a.html && a.key == "class") {
2340− let existing = attr.value.take().unwrap_or_default();
2342− Some(format!("{} {}", existing, class).trim().to_string());
2344− None => root.attrs.push(Attribute {
2345− key: "class".to_string(),
2346− value: Some(class),
2354− if !forwarded.is_empty() {
2355− problems.push(format!(
2356− "attributes {} on @{} are not parameters, and its body has no single \
2357− root element to receive them",
2360− .map(|a| format!("'{}'", a.key))
2361− .collect::<Vec<_>>()
2366− if scope_class.is_some() {
2367− problems.push(format!(
2368− "@{} has a scoped @style, but its body has no single root element \
2375− for message in problems {
2376− ctx.diagnostics.push(
2377− Diagnostic::error(code::NO_SINGLE_ROOT, line_num, message)
1173+ // A function with a scoped @style wraps its output in the scope class
1174+ if ctx.scoped_functions.contains(name) {
1175+ let wrapper = Element {
1176+ kind: ElementKind::El,
1177+ attrs: vec![Attribute {
1178+ key: "class".to_string(),
1179+ value: Some(format!("hl-{}", name)),
1183+ children: result_nodes,
1186+ result_nodes = vec![Node::Element(wrapper)];
2384 Ok(result_nodes)
1189 Ok(result_nodes)
2388−/// A `@name` read where it is written: a built-in element, or a call.
1192+ fn parse_element_line(
2389−enum Resolved {
1193+ &mut self,
2390− Element(Element),
1194+ content: &str,
2391− Call(Box<Call>),
1195+ children: &[Syntax],
2392−}
1196+ line_num: usize,
1197+ ctx: &mut ParseContext,
1198+ ) -> Result<Node, ParseError> {
1199+ let segments = split_chain(content);
2394−/// A call of a function, with its arguments evaluated where it is written.
1201+ // Parse each segment into an Element
2395−struct Call {
1202+ let mut elements: Vec<Element> = Vec::new();
2396− name: String,
1203+ for seg in &segments {
2397− function: Rc<FnDef>,
1204+ let elem = parse_single_element(seg.trim(), line_num, ctx)?;
2398− args: Vec<Attribute>,
1205+ elements.push(elem);
2399− /// The value of each argument that passes a parameter, with its type
1206+ }
2400− /// (see [`ParseContext::slot_value`]), in the order of `args`.
2401− values: Vec<Option<Value>>,
2402− /// Text after the attributes, which is content.
2403− text: Option<syntax::Text>,
2404− /// Parameters written `name=value`, already reported.
2405− written_form: Vec<String>,
2406− /// The keys written in the call's own list, not from a bundle.
2407− written_keys: Vec<String>,
2409− /// The column of the call's name and the line it is on, for a missing
2411− name_at: Option<(usize, String)>,
2412− /// The line as written, for diagnostics.
2416−/// What `@name` is where it is written: a call of the function `name`
1208+ // Parse indented children (belong to the innermost element)
2417−/// when one is defined, else the built-in element. A whole line, each link
1209+ let children = self.eval_block(children, ctx);
2418−/// of a chain and an inline element in text all resolve here.
2420− head: &syntax::Head,
2421− text: Option<&syntax::Text>,
2424− ctx: &mut ParseContext,
2425−) -> Result<Resolved, ParseError> {
2426− let Some(function) = ctx.env.function(&head.name).cloned() else {
2427− return parse_single_element(head, text, line, ctx).map(Resolved::Element);
2429− ctx.used_functions.insert(head.name.clone());
2430− let params: Vec<String> = function.params.iter().map(|p| p.name.clone()).collect();
2431− let written = head.attrs.as_ref().map_or(&[][..], |list| &list.attrs[..]);
2432− let written_form = written_parameter_forms(&head.name, &function, written, line, ctx);
2433− let written_keys = written.iter().map(|a| a.key.clone()).collect();
2434− // Parameters are bound by name; every other attribute goes to the
2435− // root element, and is checked like any attribute
2436− let (args, values) = parse_attrs(written, line, ctx, true, ¶ms)
2439− let name_at = name_column(head, line).zip(match &ctx.current_source {
2440− (current, Some(text)) if *current == line => Some(text.clone()),
2443− Ok(Resolved::Call(Box::new(Call {
2444− name: head.name.clone(),
2448− text: text.cloned(),
2453− source: source.to_string(),
2457−/// A line of another file (the standard library, an included file) means
1211+ // Build chain right-to-left: rightmost gets children, each wraps the next
2458−/// nothing in this one: the problems reported since `before` while
1212+ let mut current_children = children;
2459−/// evaluating the function (its body, a default) are moved to the call.
1213+ for mut elem in elements.into_iter().rev() {
2460−fn point_at_call(
1214+ elem.children.extend(current_children);
2461− ctx: &mut ParseContext,
1215+ current_children = vec![Node::Element(elem)];
2462− before: usize,
1216+ }
2463− function: &FnDef,
1217+
2464− name: &str,
1218+ current_children.into_iter().next().ok_or(ParseError {
2465− line: usize,
1219+ line: line_num,
2466− source: &str,
1220+ message: "element chain produced no nodes (this is a parser bug)".to_string(),
2468− if function.file == ctx.current_file {
2471− let defined_in = function
2474− .unwrap_or("the file being compiled");
2475− for d in &mut ctx.diagnostics[before..] {
2476− d.message = format!(
2477− "{}\n in @{} (line {} of {})",
2478− d.message, name, d.line, defined_in
2483− d.suggestion = None;
2484− d.source_line = Some(source.into());
2488−/// A call nested deeper than [`MAX_CALL_DEPTH`].
1225+// ---------------------------------------------------------------------------
2489−fn too_deep(name: &str, stack: &[String], line: usize) -> Diagnostic {
1226+// @children replacement
2490− let message = if stack.iter().any(|n| n == name) {
1227+// ---------------------------------------------------------------------------
2492− "recursive function call to @{} goes more than {} calls deep: a function that \
2493− calls itself needs a condition that stops it (`@if`)",
2494− name, MAX_CALL_DEPTH
2498− "function calls nest more than {} deep at @{} (starting with {})",
2504− .map(|n| format!("@{}", n))
2505− .collect::<Vec<_>>()
2509− Diagnostic::error(code::RECURSIVE_CALL, line, message).subject(name)
2512−/// Mark what a function's body wrote as the call's: it gets the call's
1229+fn replace_children_and_slots(
2513−/// line, so what is reported about it points at the call, and the name of
1230+ nodes: Vec<Node>,
2514−/// the function, unless a call inside the body already claimed it.
1231+ caller_children: &[Node],
2515−fn belongs_to_call(nodes: &mut [Node], function: &str, line: usize) {
1232+ slot_contents: &HashMap<String, Vec<Node>>,
2516− fn claim(element: &mut Element, function: &str, line: usize) {
1233+) -> Vec<Node> {
2517− element.line_num = line;
1234+ let mut result = Vec::new();
2518− element.function.get_or_insert_with(|| function.to_string());
2519− belongs_to_call(&mut element.children, function, line);
2521 for node in nodes {
1235 for node in nodes {
2522 match node {
1236 match node {
2523− Node::Element(element) => claim(element, function, line),
1237+ Node::Element(elem) if elem.kind == ElementKind::Children => {
2524− Node::Text(segments) => {
1238+ if caller_children.is_empty() && !elem.children.is_empty() {
2525− for segment in segments {
1239+ // Use @children's own children as default/fallback content
2526− if let TextSegment::Inline(element) = segment {
1240+ result.extend(elem.children);
2527− claim(element, function, line);
1241+ } else {
2528− }
1242+ result.extend(caller_children.iter().cloned());
2531− Node::Raw(_) => {}
1245+ Node::Element(elem) if matches!(&elem.kind, ElementKind::Slot(name) if !name.is_empty()) =>
2533− }
1247+ if let ElementKind::Slot(ref name) = elem.kind {
2534−}
1248+ if let Some(content) = slot_contents.get(name) {
2535−
1249+ result.extend(content.iter().cloned());
2536−/// What an inline `{@name ...}` stands for in its line of text: an
1250+ }
2537−/// element; the text of a function whose body is text; or, for a body with
1251+ // If no content provided for this slot, use the slot's own children as default
2538−/// several roots, its nodes as a fragment.
1252+ else if !elem.children.is_empty() {
2539−fn inline_segments(mut nodes: Vec<Node>, line: usize) -> Vec<TextSegment> {
1253+ result.extend(elem.children);
2540− if let [Node::Element(_)] = nodes.as_slice()
1254+ }
2541− && let Some(Node::Element(element)) = nodes.pop()
2543− return vec![TextSegment::Inline(element)];
2545− if nodes.iter().all(|n| matches!(n, Node::Text(_))) {
2546− let mut segments = Vec::new();
2547− for node in nodes {
2548− if let Node::Text(run) = node {
2549− if !segments.is_empty() {
2550− segments.push(TextSegment::Plain(" ".to_string()));
2552− segments.extend(run);
1257+ Node::Element(mut elem) => {
1259+ replace_children_and_slots(elem.children, caller_children, slot_contents);
1260+ result.push(Node::Element(elem));
1262+ other => result.push(other),
2557− vec![TextSegment::Inline(Element {
1265+ result
2558− kind: ElementKind::Fragment,
2567−/// Fill in the default of a parameter that a call leaves out, like the
1268+// ---------------------------------------------------------------------------
2568−/// value of an attribute passed for it: variables are filled in, one
1269+// Element parsing
2569−/// `$name` keeps its type and one `"..."` is quoted text. It sees what the
1270+// ---------------------------------------------------------------------------
2570−/// body sees: the names visible where the function is defined, and the
1271+
2571−/// parameters before it. Its problems are reported at the definition, once.
1272+fn extract_element_name(content: &str) -> &str {
2572−fn fill_default(
1273+ let without_at = &content[1..];
2573− fn_def: &FnDef,
1274+ match without_at.find([' ', '[']) {
2574− param: &syntax::Param,
1275+ Some(i) => &without_at[..i],
2575− default: &str,
1276+ None => without_at,
2576− ctx: &mut ParseContext,
2578− // A default that uses a later parameter is an error in the
2579− // definition; the later one isn't bound yet, so don't report it again
2583− .skip_while(|p| p.name != param.name)
2585− let names = interp::names(default);
2586− if later.clone().any(|p| names.contains(&p.name.as_str())) {
2587− return Value::empty();
2589− let line = param.span.line;
2590− let at_head = line == fn_def.line && fn_def.source.is_some();
2592− at_head.then(|| param.span.column + (param.span.end - param.span.start) - default.len());
2595− &mut ctx.current_source,
2596− (fn_def.line, fn_def.source.clone()),
2598− std::mem::replace(&mut ctx.current_node, fn_def.node),
2600− let (value, _) = ctx.slot_value(default, line, column);
2601− (ctx.current_source, ctx.current_node) = caller;
2605−/// Read `@page`'s attribute list and title. The page is the root element,
1280+fn parse_single_element(
2606−/// and its attributes are checked like any element's: `key=value` (and a
1281+ content: &str,
2607−/// bare boolean HTML attribute) go on `<html>`, styles on `<body>`, and
1282+ line_num: usize,
2608−/// `favicon FILE` is its one word of htmlang's own.
2610− attrs: Option<&syntax::AttrList>,
2611− title: Option<&syntax::Arg>,
2613 ctx: &mut ParseContext,
1283 ctx: &mut ParseContext,
2614−) -> Page {
1284+) -> Result<Element, ParseError> {
2615− let mut page = Page::default();
1285+ let (kind, rest) = if let Some(without_at) = content.strip_prefix('@') {
2616− if let Some(list) = attrs {
1286+ match without_at.find([' ', '[']) {
2617− let words: Vec<String> = crate::vocab::PAGE_WORDS
1287+ Some(i) => {
2618− .iter()
1288+ let kind_str = &without_at[..i];
2619− .map(|w| w.to_string())
1289+ let rest = if without_at.as_bytes()[i] == b'[' {
2620− .collect();
1290+ without_at[i..].to_string()
2621− ctx.in_page = true;
1291+ } else {
2622− let read = parse_attr_list(&list.attrs, line, ctx, true, &words);
1292+ without_at[i + 1..].to_string()
2623− ctx.in_page = false;
1293+ };
2624− // How many of each name have been read, to find where the next
1294+ match parse_element_kind(kind_str, line_num) {
2625− // one is written
1295+ Ok(kind) => (kind, rest),
2626− let mut seen: HashMap<String, usize> = HashMap::new();
1296+ Err(mut e) => {
2627− for attr in read {
1297+ // Also suggest user-defined functions
2628− let boolean = attr.value.is_none() && crate::vocab::is_html_flag(&attr.key);
1298+ if let Some(fn_suggestion) = suggest_fn_name(kind_str, ctx) {
2629− // Where it is written, when it is written in the list itself
1299+ e.message =
2630− let nth = seen.entry(attr.key.clone()).or_default();
1300+ format!("{}, or did you mean @{}?", e.message, fn_suggestion);
2631− let column = list
1301+ }
2632− .attrs
1302+ return Err(e);
2634− .filter(|token| token.key == attr.key)
2636− .map(|token| token.span.column);
2641− .map(|q| q.text.clone())
2642− .or(attr.value.clone());
2643− if !check_page_attr(&attr.key, attr.html, value.as_deref(), line, column, ctx) {
2646− if words.contains(&attr.key) {
2647− if page.favicon.is_some() {
2648− let diagnostic = Diagnostic::warning(
2649− code::DUPLICATE_ATTRIBUTE,
2651− "duplicate attribute 'favicon': the later one wins".to_string(),
2653− .subject("favicon");
2654− ctx.diagnostics.push(at_attribute(diagnostic, column, ctx));
2656− // The file itself goes into the page when it can be read
2657− // (relative to the file); otherwise it is linked
2658− page.favicon = value.map(|path| match std::fs::read(ctx.resolve(&path)) {
2659− Ok(data) => crate::codegen::data_uri(&path, &data),
2662− } else if attr.html || boolean {
2663− page.html_attrs.push(attr);
2665− page.styles.push(attr);
2667− }
1306+ None => match parse_element_kind(without_at, line_num) {
2668− }
1307+ Ok(kind) => (kind, String::new()),
2669− page.title = match title {
1308+ Err(mut e) => {
2670− Some(title) => ctx.interpolate_text(&title.raw, title.span.line, Some(title.span.column)),
1309+ if let Some(fn_suggestion) = suggest_fn_name(without_at, ctx) {
2671− None => String::new(),
1310+ e.message = format!("{}, or did you mean @{}?", e.message, fn_suggestion);
2676−/// `@page`'s own rules for one of its attributes, checked where the
2677−/// `@page` runs and where it doesn't (a layout that isn't called): its
2678−/// word is written `favicon FILE`, and `inline` belongs to `@image`.
2679−/// Returns whether the attribute can be used (a `favicon` with its file,
2680−/// or any other attribute but `inline`).
2684− value: Option<&str>,
2686− column: Option<usize>,
2687− ctx: &mut ParseContext,
2689− let report = |ctx: &mut ParseContext, diagnostic: Diagnostic| {
2690− let diagnostic = at_attribute(diagnostic, column, ctx);
2691− ctx.diagnostics.push(diagnostic);
2693− if crate::vocab::PAGE_WORDS.contains(&key) {
2698− code::PARAMETER_FORM,
2701− "'{0}' is @page's own word, not an HTML attribute: write `{0} {1}`",
2703− value.filter(|v| !v.is_empty()).unwrap_or("FILE")
2706− .subject(format!("{}=", key))
2707− .suggest(Some(format!("{} ", key))),
2710− if value.is_none_or(|v| v.trim().is_empty()) {
2714− code::MISSING_VALUE,
2716− format!("'{0}' needs its file: `{0} favicon.png`", key),
2724− if !html && crate::vocab::base_attribute(key) == "inline" {
2728− code::UNEXPECTED_ARGUMENT,
2730− "`inline` puts an image's file into the page, and @page has none: it only \
2734− .subject("inline"),
2741−/// A parameter passed `name=value`, the form of an HTML attribute.
2742−fn parameter_form(function: &str, key: &str, value: &str, line: usize) -> Diagnostic {
2744− code::PARAMETER_FORM,
2747− "'{}' is a parameter of @{}: parameters are written `name value`, so write `{} {}`",
2748− key, function, key, value
2751− .subject(format!("{}=", key))
2752− .suggest(Some(format!("{} ", key)))
2755−/// A call that leaves out a parameter without a default.
2756−fn missing_parameter(
2760− column: Option<usize>,
2762− let diagnostic = Diagnostic::error(
2763− code::MISSING_PARAMETER,
2766− "@{} needs '{}': the parameter has no default, so pass it as `{} VALUE`",
2767− function, param, param
2772− Some(column) => diagnostic.column(column),
2773− None => diagnostic,
2777−/// The column of a call's `@name`, when it is on the call's line.
2778−fn name_column(head: &syntax::Head, line: usize) -> Option<usize> {
2779− (head.name_span.line == line).then_some(head.name_span.column)
2782−/// Define `$name`, or, for `--name`, the CSS custom property on `:root`
2783−/// (which gets quoted text with its quotes, and is read with
2784−/// `var(--name)`, never as a variable). `@let name.field value` gives the
2785−/// record `$name` that field (or the list `$name` a new item at that
2786−/// index), as a new value in this block.
2787−fn set_variable(name: &str, value: Value, line_num: usize, ctx: &mut ParseContext) {
2788− if name.starts_with("--") {
2791− .map_or_else(|| value.to_string(), str::to_string);
2792− let at_line = |diagnostic: Diagnostic, ctx: &ParseContext| match &ctx.current_source {
2793− (current, Some(text)) if *current == line_num => diagnostic.source(text.clone()),
2796− // `:root` is one place for the whole page: a declaration inside a
2797− // block (an element, a loop, a function's body) would not be
2798− // kept to it, and each run would replace the last
2799− if ctx.env.frames.len() > FILE_FRAMES {
2800− let diagnostic = Diagnostic::error(
2801− code::INVALID_DEFINITION,
2804− "`@let {name}` declares {name} on :root, for the whole page, so it goes at \
2805− the top level of the file: to set it on an element and what is inside \
2806− it, write `[{name} value]` on that element"
2810− ctx.push_once(at_line(diagnostic, ctx));
2813− match css_breakout(&css) {
2815− let diagnostic = Diagnostic::error(
2816− code::INVALID_VALUE,
2819− "the value of '{}' has {}: `{}` can't be written into the page's CSS",
2823− .subject(css.as_str());
2824− ctx.push_once(at_line(diagnostic, ctx));
2826− None => match ctx.css_vars.iter_mut().find(|(n, _)| n == name) {
2827− Some(declared) => {
2828− let diagnostic = Diagnostic::warning(
2829− code::DUPLICATE_ATTRIBUTE,
2832− "{name} is declared again: :root has one value for the whole page, \
2833− so every element gets this one, also above this line (a theme \
2834− redefines a token on an element: `[dark:{name} {css}]`)"
2839− ctx.push_once(at_line(diagnostic, ctx));
2841− None => ctx.css_vars.push((name.to_string(), css)),
2846− let mut path = name.split('.');
2847− let root = path.next().unwrap_or(name);
2848− let fields: Vec<&str> = path.collect();
2849− let value = match fields.is_empty() {
2851− false => match with_field(ctx.env.value(root).cloned(), root, &fields, value) {
2852− Ok(value) => value,
2855− Diagnostic::error(code::INVALID_DEFINITION, line_num, message).subject(name);
2856− let diagnostic = match &ctx.current_source {
2857− (current, Some(text)) if *current == line_num => {
2858− diagnostic.source(text.clone())
2862− ctx.push_once(diagnostic);
2863− // Reported: the name keeps what it held
2864− ctx.let_lines.entry(root.to_string()).or_insert(line_num);
2869− ctx.bind(root, value);
2870− ctx.let_lines.entry(root.to_string()).or_insert(line_num);
2873−/// `value` (the value of `$name`) with the field at `path` set to `new`:
2874−/// a record's field, or the item of a list at an index it has. A name
2875−/// without a value, or one whose value is empty (a field a record doesn't
2876−/// have), becomes a record; any other value has no fields to set.
2878− value: Option<Value>,
2882−) -> Result<Value, String> {
2883− let Some((field, rest)) = path.split_first() else {
2886− let inner = format!("{}.{}", name, field);
2888− Some(Value::Record(fields)) => {
2889− let mut fields = fields.as_ref().clone();
2890− match fields.iter().position(|(key, _)| key == field) {
2892− let old = std::mem::replace(&mut fields[i].1, Value::empty());
2893− fields[i].1 = with_field(Some(old), &inner, rest, new)?;
2895− None => fields.push((field.to_string(), with_field(None, &inner, rest, new)?)),
2897− Ok(Value::Record(Rc::new(fields)))
2899− Some(Value::List(list)) => {
2900− let count = list.items.len();
2901− let Some(i) = field.parse::<usize>().ok().filter(|&i| i < count) else {
2902− return Err(format!(
2903− "`${}` is {}, so `.{}` isn't one of its items (they are `.0` to `.{}`)",
2905− Value::List(list).describe(),
2907− count.saturating_sub(1)
2910− let mut items = list.items.as_ref().clone();
2911− let old = std::mem::replace(&mut items[i], Value::empty());
2912− items[i] = with_field(Some(old), &inner, rest, new)?;
2913− // Its items changed, so it no longer prints as written
2914− Ok(Value::list(items))
2916− None => Ok(Value::Record(Rc::new(vec![(
2918− with_field(None, &inner, rest, new)?,
2920− Some(value) if value.to_string().is_empty() => with_field(None, name, path, new),
2921− Some(value) => Err(format!(
2922− "`@let {}.{}` sets a field of a record, but `${}` is {} (`{}`), which has no fields",
2932−/// What a verbatim directive holds (`@head`, `@style`, `@raw`): the rest
2933−/// of its line (`@style .a { color: red }`), or else its indented block.
2934−/// The two together are a syntax error, reported by the tree; the line
2936−fn verbatim_content(node: &syntax::Node) -> String {
2937− match node.directive().map(|d| &d.args) {
2938− Some(DirectiveArgs::Text(Some(line))) => format!("{}\n", line.raw),
2939− _ => verbatim_text(&node.children),
2943−/// The text of a verbatim body (`@head`, `@style`, `@markdown`, `@raw`).
2944−fn verbatim_text(children: &[syntax::Node]) -> String {
2945− let mut text = String::new();
2946− for child in children {
2947− if let NodeKind::Verbatim(body) = &child.kind {
2948− text.push_str(&body.text);
2955−// ---------------------------------------------------------------------------
2956−// @children replacement
2957−// ---------------------------------------------------------------------------
2959−fn replace_children_and_slots(
2961− caller_children: &[Node],
2962− slot_contents: &HashMap<String, Vec<Node>>,
2964− let mut result = Vec::new();
2965− for node in nodes {
2967− Node::Element(elem) if elem.kind == ElementKind::Children => {
2968− if caller_children.is_empty() && !elem.children.is_empty() {
2969− // Use @children's own children as default/fallback content
2970− result.extend(elem.children);
2972− result.extend(caller_children.iter().cloned());
2975− Node::Element(elem) if matches!(&elem.kind, ElementKind::Slot(name) if !name.is_empty()) =>
2977− if let ElementKind::Slot(ref name) = elem.kind {
2978− if let Some(content) = slot_contents.get(name) {
2979− result.extend(content.iter().cloned());
2981− // If no content provided for this slot, use the slot's own children as default
2982− else if !elem.children.is_empty() {
2983− result.extend(elem.children);
2987− Node::Element(mut elem) => {
2989− replace_children_and_slots(elem.children, caller_children, slot_contents);
2990− result.push(Node::Element(elem));
2992− other => result.push(other),
2998−// ---------------------------------------------------------------------------
2999−// Where @slot and @children are written
3000−// ---------------------------------------------------------------------------
3002−/// The files each `@include` line brought in, by the line's node id, with
3003−/// the include chain that leads to each.
3004−type IncludedBy = HashMap<usize, Vec<(Rc<Tree>, String)>>;
3006−/// The lines of the files an `@include` line brings in, and the include
3007−/// chain of each (for diagnostics).
3008−type Included<'a, 'f> = &'f dyn Fn(&syntax::Node) -> Vec<(&'a [syntax::Node], Option<&'a str>)>;
3010−/// Whether `name` is a function here: defined so far, or anywhere in the
3011−/// file and the files it includes.
3012−fn is_function(name: &str, ctx: &ParseContext) -> bool {
3013− ctx.env.function(name).is_some() || ctx.namespace.contains(name)
3016−/// Whether `name` is one slot name: letters, digits, `-` and `_`,
3017−/// starting with a letter (like a function's name).
3018−fn is_slot_name(name: &str) -> bool {
3019− name.chars().next().is_some_and(char::is_alphabetic)
3022− .all(|c| c.is_alphanumeric() || c == '-' || c == '_')
3025−/// What a `@slot` or `@children` line is written in.
3026−#[derive(Clone, Copy)]
3028− /// The top of a file or of a function's body, or a built-in element
3030− Element(Option<&'a str>),
3031− /// A call: its content.
3035−/// Where a line is, for [`slot_uses`].
3036−#[derive(Clone, Copy)]
3038− /// Inside a function's body.
3041− /// Outside a body: the call (and its line) whose content it is in.
3042− call: Option<(&'a str, usize)>,
3043− /// The include chain of the file it is in, when that isn't the file
3044− /// being compiled.
3045− file: Option<&'a str>,
3049− /// The top of a file, or of a function's body.
3050− fn top(body: bool) -> Self {
3053− place: Place::Element(None),
3060−/// What [`slot_uses`] knows about the names and files it walks.
3061−struct Scan<'a, 'f> {
3062− is_function: &'f dyn Fn(&str) -> bool,
3063− included: Included<'a, 'f>,
3064− /// Visit the bodies of the functions defined in the lines too.
3068−/// A `@slot` or `@children` written in a file, and where.
3069−struct SlotUse<'a> {
3070− node: &'a syntax::Node,
3071− head: &'a syntax::Head,
3072− /// The text after it, which is a slot's name; `None` when it isn't
3073− /// the last head of its chain.
3074− text: Option<&'a syntax::Text>,
3075− /// Written inline in a line of text, `{@slot x}`.
3081− fn is_slot(&self) -> bool {
3082− self.head.name == "slot"
3085− /// The slot's name as written.
3086− fn name(&self) -> &str {
3087− self.text.map_or("", |t| t.raw.trim())
3090− /// A `@slot NAME` that marks a place in a function's body (not one
3091− /// that fills a slot of a call).
3092− fn declares(&self) -> bool {
3093− self.is_slot() && !self.inline && !matches!(self.at.place, Place::Call)
3097−/// Where each `@slot` and `@children` in `block` is written. A `@slot`
3098−/// directly under a call (under its `@if`, `@else` and `@each` too) fills
3099−/// one of its slots; anywhere else in a function's body it declares one.
3100−/// An included file's lines are where its `@include` is.
3102− block: &'a [syntax::Node],
3104− scan: &Scan<'a, '_>,
3105− out: &mut Vec<SlotUse<'a>>,
3108− text: &'a syntax::Text,
3109− node: &'a syntax::Node,
3111− scan: &Scan<'a, '_>,
3112− out: &mut Vec<SlotUse<'a>>,
3114− for segment in &text.segments {
3115− if let Segment::Inline(inline_element) = segment {
3116− let head = &inline_element.head;
3117− if matches!(head.name.as_str(), "slot" | "children")
3118− && !(scan.is_function)(&head.name)
3123− text: inline_element.text.as_ref(),
3128− if let Some(text) = &inline_element.text {
3129− inline(text, node, at, scan, out);
3134− for node in block {
3136− NodeKind::Directive(directive) => match &directive.args {
3137− DirectiveArgs::Let(def) if matches!(def.form, LetForm::Function(_)) => {
3138− if scan.into_lets {
3143− slot_uses(&node.children, top, scan, out);
3146− // A value's body is an error of its own
3147− DirectiveArgs::Let(_) => {}
3148− _ if directive.spec.body == BodyKind::Verbatim => {}
3149− // `@if`, `@else` and `@each` put their lines in place, and
3150− // `@include` its file's; the lines under a directive that
3151− // takes no body are its siblings
3153− for (lines, file) in (scan.included)(node) {
3154− slot_uses(lines, At { file, ..at }, scan, out);
3156− slot_uses(&node.children, at, scan, out);
1312+ return Err(e);
3159− NodeKind::Element(line) => {
3161− let last = line.chain.len() - 1;
3162− for (i, head) in line.chain.iter().enumerate() {
3163− let text = if i == last { line.text.as_ref() } else { None };
3164− let function = (scan.is_function)(&head.name);
3165− if !function && matches!(head.name.as_str(), "slot" | "children") {
3173− } else if let Some(text) = text {
3174− inline(text, node, at, scan, out);
3177− at.place = Place::Call;
3179− at.call = Some((&head.name, node.span.line));
3182− at.place = Place::Element(Some(&head.name));
3185− slot_uses(&node.children, at, scan, out);
3187− NodeKind::Text(text) => {
3188− inline(text, node, at, scan, out);
3189− slot_uses(&node.children, at, scan, out);
3191− NodeKind::Blank | NodeKind::Comment | NodeKind::Verbatim(_) => {}
3194−}
1317+ return Err(ParseError {
3195−
1318+ line: line_num,
3196−/// The slots a function's body declares, and whether it has a
1319+ message: format!("expected @element or [attrs], got: {}", content),
3197−/// `@children`, when it is defined. The files its `@include` lines bring
3198−/// in count too: they are read now, since they run only at a call.
3199−fn declared_slots(body: &[syntax::Node], ctx: &mut ParseContext) -> (Vec<String>, bool) {
3200− let mut files = HashMap::new();
3203− ctx.base_path.clone(),
3208− let included = |node: &syntax::Node| match files.get(&node.id) {
3209− Some(tree) => vec![(&tree.nodes[..], None)],
3210− None => Vec::new(),
3212− let is_function = |name: &str| is_function(name, ctx);
3213− slots_of(body, &is_function, &included)
3216−/// Read and parse the files the `@include` lines in `nodes` bring in (by
3217−/// a literal path, relative to `base`), and the files those include, by
3218−/// the node id of each `@include` line.
3220− nodes: &[syntax::Node],
3221− base: Option<PathBuf>,
3222− stack: &mut Vec<PathBuf>,
3223− ctx: &mut ParseContext,
3224− files: &mut HashMap<usize, Rc<Tree>>,
3226− let mut includes = Vec::new();
3227− for node in nodes {
3228− node.walk(&mut |node| {
3229− if let Some(DirectiveArgs::Text(Some(path))) = node.directive().map(|d| &d.args)
3230− && node.is_directive("include")
3232− includes.push((node.id, path.raw.clone()));
3236− for (id, path) in includes {
3237− let path = path.trim_matches('"');
3238− if path.contains('$') {
3241− let resolved = match &base {
3242− Some(base) => base.join(path),
3243− None => PathBuf::from(path),
3245− if stack.contains(&resolved) {
3248− let Ok(text) = ctx.read_file(&resolved) else {
3251− let tree = ctx.parse_tree(&text);
3252− stack.push(resolved.clone());
3253− let parent = resolved.parent().map(Path::to_path_buf);
3254− read_includes(&tree.nodes, parent, stack, ctx, files);
3256− files.insert(id, tree);
3260−/// The slots a function's body declares (`@slot NAME`, in order), and
3261−/// whether it has a `@children` for the content of a call. A `@slot`
3262−/// directly under a call in the body fills that call's slot instead, so
3263−/// `is_function` says which names are functions. The files the body
3264−/// includes aren't read.
3265−pub fn function_slots(
3266− body: &[syntax::Node],
3267− is_function: &dyn Fn(&str) -> bool,
3268−) -> (Vec<String>, bool) {
3269− slots_of(body, is_function, &|_| Vec::new())
3273− body: &'a [syntax::Node],
3274− is_function: &dyn Fn(&str) -> bool,
3275− included: Included<'a, '_>,
3276−) -> (Vec<String>, bool) {
3282− let mut uses = Vec::new();
3283− slot_uses(body, At::top(true), &scan, &mut uses);
3284− let mut slots: Vec<String> = Vec::new();
3285− for slot in uses.iter().filter(|u| u.declares()) {
3286− let name = slot.name();
3287− if is_slot_name(name) && !slots.iter().any(|s| s == name) {
3288− slots.push(name.to_string());
3291− let has_children = uses.iter().any(|u| !u.is_slot() && !u.inline);
3292− (slots, has_children)
3295−/// The line as written, indented, when it is one physical line, so a
3296−/// column points into it.
3297−fn written_line(node: &syntax::Node) -> String {
3298− match node.line_count <= 1 {
3299− true => format!("{}{}", " ".repeat(node.indent), node.source),
3300− false => node.source.clone(),
3304−/// The lines of the files an `@include` line brought in when it ran, from
3306−fn ran_includes<'a>(
3307− included_by: &'a IncludedBy,
3308− node: &syntax::Node,
3309−) -> Vec<(&'a [syntax::Node], Option<&'a str>)> {
3310− match included_by.get(&node.id) {
3311− Some(files) => files
3313− .map(|(tree, chain)| (&tree.nodes[..], Some(chain.as_str())))
3315− None => Vec::new(),
3319−/// Check where every `@slot` and `@children` of the file and the files it
3320−/// includes is written, whether or not it runs: a slot has one name, a
3321−/// function's body marks places with them, and a call fills its slots
3322−/// with `@slot` blocks directly under it. An included file's lines are
3323−/// where its `@include` is (in a body, under a call), so an `@include`
3324−/// that never ran leaves its file unchecked.
3325−fn check_slot_places(ctx: &mut ParseContext) {
3326− let trees = std::mem::take(&mut ctx.trees);
3327− let included_by = ctx.included_by.clone();
3328− let is_function = |name: &str| is_function(name, ctx);
3330− is_function: &is_function,
3331− included: &|node| ran_includes(&included_by, node),
3334− let mut uses = Vec::new();
3335− for (tree, _) in trees.iter().filter(|(_, chain)| chain.is_none()) {
3336− slot_uses(&tree.nodes, At::top(false), &scan, &mut uses);
3338− let found: Vec<Diagnostic> = uses
3340− .filter_map(|slot| {
3341− let mut d = slot_problem(slot)?;
3342− if d.column.is_none() {
3343− d = d.column(slot.head.name_span.column);
3345− d = d.source(written_line(slot.node));
3346− if let Some(file) = slot.at.file {
3347− d.message = format!("{}\n in {}", d.message, file);
3352− ctx.diagnostics.extend(found);
3356−/// What is wrong with a `@slot` or `@children` where it is written.
1323+ // Parse optional [attrs]
3357−fn slot_problem(slot: &SlotUse) -> Option<Diagnostic> {
1324+ let (attrs, rest) = if rest.starts_with('[') {
3358− let line = slot.node.span.line;
1325+ parse_attr_brackets(&rest, line_num, ctx)?
3359− let what = if slot.is_slot() {
3360− match slot.name() {
3361− "" => "@slot".to_string(),
3362− name => format!("@slot {}", name),
3364 } else {
1326 } else {
3365− "@children".to_string()
1327+ (Vec::new(), rest)
3368− return Some(Diagnostic::error(
3369− code::MISPLACED_SLOT,
3372− "{} goes on a line of its own: inline in text it marks and fills nothing",
3377− if let Some(list) = &slot.head.attrs {
3380− code::UNEXPECTED_ARGUMENT,
3383− "{} takes no attributes: it is replaced by content, so style the \
3384− element around it",
3388− .column(list.span.column),
3391− if slot.is_slot() {
3392− let name = slot.name();
3393− if name.is_empty() {
3394− return Some(Diagnostic::error(
3395− code::MISSING_ARGUMENT,
3397− "@slot needs a name: `@slot footer` (the caller's content without a \
3398− name goes where `@children` is)"
3402− if !is_slot_name(name) {
3403− let joined = name.split_whitespace().collect::<Vec<_>>().join("-");
3404− let suggestion = is_slot_name(&joined).then_some(joined);
3405− let column = slot.text.map(|t| t.span.column);
3406− let d = Diagnostic::error(
3407− code::INVALID_SLOT_NAME,
3410− "'{}' is not a slot name: a slot's name is one word of letters, digits, \
3411− `-` and `_`, starting with a letter, and its content goes on the lines \
3417− .suggest(suggestion);
3418− return Some(match column {
3419− Some(column) => d.column(column),
3423− if matches!(slot.at.place, Place::Call) || slot.at.body {
3426− let message = match (slot.at.call, slot.at.place) {
3427− (Some((call, call_line)), Place::Element(Some(element))) => format!(
3428− "{} is inside @{}, so it fills nothing: a @slot block that fills a slot of \
3429− @{} (line {}) goes directly under the call",
3430− what, element, call, call_line
3433− "{} is outside a function's body: `@slot NAME` marks a place in a body \
3434− (`@let @name`), and directly under a call it fills one",
3438− return Some(Diagnostic::error(code::MISPLACED_SLOT, line, message));
3443− let message = match slot.at.call {
3444− Some((call, _)) => format!(
3445− "@children is outside a function's body, so it stands for nothing: the content \
3446− for @{} is written directly under the call",
3449− None => "@children is outside a function's body: it marks where a body puts the \
3450− content of each call"
3453− Some(Diagnostic::error(code::MISPLACED_SLOT, line, message))
3456−/// A `@slot NAME` block that fills a slot of a call.
3458− node: &'a syntax::Node,
3459− text: &'a syntax::Text,
3460− /// The include chain of the file it is in, when that isn't the file
3461− /// being compiled.
3462− file: Option<&'a str>,
3465−/// Whether `@slot` is the built-in element here, and not a function
1330+ let rest = rest.trim().to_string();
3466−/// defined so far that took its name.
1331+ track_var_refs(&rest, &mut ctx.used_variables);
3467−fn slot_is_built_in(ctx: &ParseContext) -> bool {
3468− ctx.env.function("slot").is_none()
3471−/// The `@slot NAME` blocks directly under a call, in `block` (under its
3472−/// `@if`, `@else` and `@each` too, and in the files its `@include` lines
3475− block: &'a [syntax::Node],
3476− file: Option<&'a str>,
3477− included: &'a IncludedBy,
3478− out: &mut Vec<Filler<'a>>,
3480− for node in block {
3482− NodeKind::Directive(directive)
3483− if matches!(directive.name(), "if" | "else" | "each") =>
3485− fillers(&node.children, file, included, out);
3487− NodeKind::Directive(directive) if directive.name() == "include" => {
3488− for (lines, file) in ran_includes(included, node) {
3489− fillers(lines, file, included, out);
3492− NodeKind::Element(line) if line.chain.len() == 1 && line.chain[0].name == "slot" => {
3493− if let Some(text) = &line.text {
3494− out.push(Filler { node, text, file });
3502−/// Whether `block`, the lines under a call, holds content other than
3503−/// `@slot` blocks (under `@if`, `@else` and `@each` too): text, an
3504−/// element, raw HTML, Markdown or an included file. For code that doesn't
3506−fn holds_content(block: &[syntax::Node], ctx: &ParseContext) -> bool {
3507− block.iter().any(|node| match &node.kind {
3508− NodeKind::Directive(directive) => match directive.name() {
3509− "if" | "else" | "each" => holds_content(&node.children, ctx),
3510− name => matches!(name, "raw" | "markdown" | "include"),
3512− NodeKind::Element(line) => {
3513− line.chain[0].name != "slot" || !slot_is_built_in(ctx) || line.chain.len() > 1
3515− NodeKind::Text(_) => true,
3520−/// Check the `@slot NAME` blocks passed to each call of a line against
3521−/// the slots its function declares. `calls` has the function of each head
3522−/// of the chain that is a call.
3524− node: &syntax::Node,
3525− element: &syntax::ElementLine,
3526− calls: &[Option<(String, Rc<FnDef>)>],
3527− ctx: &mut ParseContext,
3529− if !slot_is_built_in(ctx) {
3532− let included = ctx.included_by.clone();
3533− let last = element.chain.len() - 1;
3534− for (i, call) in calls.iter().enumerate() {
3535− let Some((name, function)) = call else {
3538− let mut found = Vec::new();
3540− fillers(&node.children, None, &included, &mut found);
3541− } else if i + 1 == last
3542− && element.chain[last].name == "slot"
3543− && let Some(text) = &element.text
3545− // `@card > @slot footer`
3546− found.push(Filler {
3552− for filler in found {
3553− let slot = filler.text.raw.trim();
3554− if !is_slot_name(slot) || function.slots.iter().any(|s| s == slot) {
3557− let mut d = unknown_slot(name, slot, &function.slots, filler.text.span.line)
3558− .column(filler.text.span.column)
3559− .source(written_line(filler.node));
3560− if let Some(file) = filler.file {
3561− d.message = format!("{}\n in {}", d.message, file);
3568−/// A `@slot NAME` block for a slot the function doesn't declare.
3569−fn unknown_slot(function: &str, slot: &str, slots: &[String], line: usize) -> Diagnostic {
3570− let candidates: Vec<&str> = slots.iter().map(String::as_str).collect();
3571− let suggestion = suggest_closest(slot, &candidates);
3572− let message = match (slots.is_empty(), suggestion) {
3573− (true, _) => format!(
3574− "@{} has no slot '{}': its body declares no slots (`@slot NAME`)",
3577− (false, Some(close)) => format!(
3578− "@{} has no slot '{}', did you mean '{}'? (its slots: {})",
3584− (false, None) => format!(
3585− "@{} has no slot '{}' (its slots: {})",
3591− Diagnostic::error(code::UNKNOWN_SLOT, line, message)
3593− .suggest(suggestion)
3596−/// Content passed to a function whose body has no `@children`.
3597−fn no_children(function: &str, line: usize, column: Option<usize>) -> Diagnostic {
3598− let d = Diagnostic::error(
3599− code::UNEXPECTED_CONTENT,
3602− "@{0} takes no content: its body has no `@children`, so the text and lines \
3603− passed to it would be dropped (pass text as a parameter, `@{0} [name value]`, \
3604− or add `@children` to the body)",
3608− .subject(function);
3610− Some(column) => d.column(column),
3615−// ---------------------------------------------------------------------------
3617−// ---------------------------------------------------------------------------
3619−/// Build the element for `@name [attrs] text` (on its own line, in a chain,
3620−/// or inline in text).
3621−fn parse_single_element(
3622− head: &syntax::Head,
3623− text: Option<&syntax::Text>,
3625− ctx: &mut ParseContext,
3626−) -> Result<Element, ParseError> {
3627− let kind = parse_element_kind(&head.name, line_num, ctx)?;
3628− let mut attrs = head.attrs.as_ref().map_or_else(Vec::new, |list| {
3629− parse_attr_list(&list.attrs, line_num, ctx, true, &[])
3632− // The leading argument: for an element whose row names a leading
1333+ // For @link, first token of rest is URL, remainder is inline text
3633− // attribute (`@link`'s href, `@image`'s src, `@form`'s action, ...),
3634− // the first token of the text fills it, split before anything is
3635− // filled in, and the rest is content (an error on an element without
3636− // content). `@slot`'s whole text is its name. Any other element's text
3637− // is content, parsed like any line of text, as in `@el [padding 8]
3638− // Hello` or `@h2 Meet {@text htmlang}`; its layout decides how it
3639− // combines with the lines under it.
3640 let mut children = Vec::new();
1334 let mut children = Vec::new();
3641− let mut argument = None;
1335+ let argument = if rest.is_empty() {
3642− let leading = kind.arg().attributes();
1336+ None
3643− match text {
1337+ } else if kind == ElementKind::Link {
3644− Some(text) if !leading.is_empty() => {
1338+ let rest_sub = substitute_vars(&rest, &ctx.variables);
3645− let (token, rest) = text.split_leading();
1339+ if let Some((url, text)) = rest_sub.split_once(' ') {
3646− let given = attrs
1340+ let text = text.trim();
3647− .iter()
1341+ if !text.is_empty() {
3648− .find(|a| a.html && leading.contains(&a.key.as_str()))
1342+ children.push(Node::Text(parse_text_segments(text, ctx)));
3649− .map(|a| (a.key.clone(), a.value.clone().unwrap_or_default()));
1343+ }
3650− if let Some((key, value)) = given {
1344+ Some(url.to_string())
3651− // The attribute wins; the text is content, as if the
1345+ } else {
3652− // element had no leading argument
1346+ Some(rest_sub)
3653− ctx.push_once(leading_twice(&kind, &token, &key, &value, text, ctx));
3654− if !takes_no_text(&kind) {
3655− children.push(Node::Text(text_segments(text, ctx)));
3657− } else if let Some(d) = bad_leading_token(&kind, &token, &text.raw, ctx) {
3658− // Nothing is taken as the argument; the line is content
3660− if !takes_no_text(&kind) {
3661− children.push(Node::Text(text_segments(text, ctx)));
3664− let column = Some(token.span.column);
3665− if let Some(d) = text_as_url(&kind, &token, ctx) {
3669− ctx.fill_value(&token.raw, text.span.line, column, Sink::Text)
3672− if let Some(rest) = rest {
3673− if let Some(d) = chain_after_argument(&kind, &token.raw, &rest, ctx) {
3676− if takes_no_text(&kind) {
3677− let d = after_the_leading_argument(&kind, &token.raw, &rest);
3678− let d = at_attribute(d, Some(rest.span.column), ctx);
3681− children.push(Node::Text(text_segments(&rest, ctx)));
3686− Some(text) if matches!(kind, ElementKind::Slot(_)) => {
3688− Some(ctx.interpolate_text(&text.raw, text.span.line, Some(text.span.column)));
3690− Some(text) => children.push(Node::Text(text_segments(text, ctx))),
3691− // `@link [href=/about]`: the attribute is the leading argument, so
3692− // both forms compile the same (`@image [src=a.svg, inline]`). Not
3693− // for `@source`, whose attribute depends on where it is.
3694− None if leading.len() == 1 => {
3695− if let Some(i) = attrs.iter().position(|a| a.html && a.key == leading[0]) {
3696− argument = Some(attrs.remove(i).value.unwrap_or_default());
3699− None => {}
1348+ } else {
3700− }
1349+ Some(substitute_vars(&rest, &ctx.variables))
3702 // For @slot, the argument is the slot name
1352 // For @slot, the argument is the slot name
3703 let kind = if let ElementKind::Slot(_) = kind {
1353 let kind = if let ElementKind::Slot(_) = kind {
@@ -3706,352 +1356,209 @@ fn parse_single_element(
1359+ // Every other element treats its argument as leading text content, as
1360+ // in `@el [padding 8] Hello` or `@paragraph Read {@link /more more}`.
1361+ let argument = match argument {
1362+ Some(_) if !argument_is_special(&kind) && !renders_argument_as_text(&kind) => {
1363+ children.insert(0, Node::Text(parse_text_segments(&rest, ctx)));
3709 Ok(Element {
1369 Ok(Element {
3712 argument,
1372 argument,
3713 children,
1373 children,
3714 line_num,
1374 line_num,
3719−/// Whether `node` or a line inside it calls `@name` outside any `@if`
1378+/// Elements whose argument is not text content: a URL, a source, an action,
3720−/// (in a chain, or inline in text).
1379+/// or a slot name.
3721−fn calls_unguarded(node: &syntax::Node, name: &str) -> bool {
1380+fn argument_is_special(kind: &ElementKind) -> bool {
3722− if node.is_directive("if") || node.is_directive("else") {
1381+ matches!(
3723− return false;
1382+ kind,
3724− }
1383+ ElementKind::Link | ElementKind::Image | ElementKind::Script | ElementKind::Slot(_)
3725− let text_calls = |text: &syntax::Text| {
1384+ ) || kind
3726− text.segments
1385+ .spec()
3727− .iter()
1386+ .is_some_and(|spec| matches!(spec.arg, TagArg::Attr(_)))
3728− .any(|s| matches!(s, Segment::Inline(inline) if inline.head.name == name))
1387+}
3730− let here = match &node.kind {
1389+/// The directive names (without `@`) the parser recognizes, for tools such
3731− NodeKind::Element(element) => {
1390+/// as the language server.
3732− element.chain.iter().any(|head| head.name == name)
1391+pub fn known_directives() -> &'static [&'static str] {
3733− || element.text.as_ref().is_some_and(text_calls)
1392+ KNOWN_DIRECTIVES
3735− NodeKind::Text(text) => text_calls(text),
1394+
3736− _ => false,
1395+const KNOWN_DIRECTIVES: &[&str] = &[
3738− here || node
1397+ "let",
3739− .children
1398+ "include",
3740− .iter()
1399+ "raw",
3741− .any(|child| calls_unguarded(child, name))
1400+ "if",
3744−/// `@td [padding 8] @children`: `@children` and `@slot NAME` mark where a
1403+ "meta",
3745−/// call's content goes only on a line of their own; after an element's
1404+ "head",
3746−/// attributes, or in a verbatim body, they are text.
1405+ "style",
3747−fn marker_in_text(node: &syntax::Node) -> Option<Diagnostic> {
1406+ "markdown",
3748− let is_marker = |text: &str| {
1407+ "data",
3749− let text = text.trim();
1408+];
3750− text == "@children" || text == "@slot" || text.starts_with("@slot ")
3752− let mut line = node.span.line;
3753− let mut source = written_line(node);
3754− let (marker, message) = match &node.kind {
3755− NodeKind::Element(element) => {
3756− let text = element.text.as_ref()?;
3757− if !is_marker(&text.raw) {
3760− let name = &element.chain.last()?.name;
3761− let marker = text.raw.trim().to_string();
3762− let message = format!(
3763− "`{marker}` after @{name}'s attributes is text: it marks where a call's content \
3764− goes only on a line of its own, so write it on the next line, indented under \
3769− NodeKind::Verbatim(verbatim) if verbatim.escaped => {
3770− let (i, written) = verbatim
3774− .find(|(_, l)| is_marker(l))?;
3775− let marker = written.trim().to_string();
3777− source = written.to_string();
3778− let message = format!(
3779− "`{marker}` in a verbatim body is text: the body is written as it is, so it can't \
3780− hold a call's content (pass the text as a parameter instead)"
3787− Diagnostic::error(code::MISPLACED_SLOT, line, message)
3793−/// A first word that can't be a leading argument: an inline element
3794−/// (`@link {@b x} y`), or a quote that isn't closed (`@link "a b`).
3795−fn bad_leading_token(
3796− kind: &ElementKind,
3797− token: &syntax::Arg,
3799− ctx: &ParseContext,
3800−) -> Option<Diagnostic> {
3801− let what = leading_name(kind);
3802− let name = kind.name();
3803− let message = if token.raw.starts_with("{@") {
3805− "@{0} takes its {1} first, before any text: write `@{0} VALUE {2}`, or give it as \
3811− } else if token.raw.starts_with('"') && syntax::quoted_string(&token.raw).is_none() {
3813− "@{}'s {} starts with a `\"` that isn't closed: close it (`\"...\"`), or write \
3814− `\\\"` for a quote in the value",
3820− let d = Diagnostic::error(code::UNEXPECTED_ARGUMENT, token.span.line, message)
3821− .subject(token.raw.clone());
3822− Some(at_attribute(d, Some(token.span.column), ctx))
3825−/// A first word taken as a URL that reads as text: a word with a capital
3826−/// and nothing a URL or a file name has, as in `@link [hx-get=/panel] Open
3827−/// panel`, whose href would be `Open`. It still is (a relative URL can be
3828−/// such a word), with a warning.
3829−fn text_as_url(kind: &ElementKind, token: &syntax::Arg, ctx: &ParseContext) -> Option<Diagnostic> {
3830− const URLS: &[&str] = &["href", "src", "srcset", "action", "data"];
3831− let word = token.raw.as_str();
3832− let reads_as_text = word.starts_with(char::is_uppercase)
3833− && !word.contains([
3834− '/', '.', ':', '#', '?', '=', '&', '%', '~', '$', '{', '\\', '"',
3836− if !reads_as_text || !kind.arg().attributes().iter().any(|a| URLS.contains(a)) {
3839− let name = kind.name();
3840− let attr = leading_name(kind);
3841− let text = if takes_no_text(kind) {
3844− format!(": write the {attr} before the text, or put the text on the lines under it")
3846− let message = format!(
3847− "@{name} takes '{word}', its first word, as its {attr}{text}. A relative URL that \
3848− starts with a capital is written `./{word}`"
3850− let d = Diagnostic::warning(code::TEXT_AS_URL, token.span.line, message).subject(word);
3851− Some(at_attribute(d, Some(token.span.column), ctx))
3854−/// `@link /a > @image logo.png`: a `>` chains only after an element's
3855−/// name or its `[attributes]`, so after a leading argument it is text.
3856−/// Said when what follows names an element or a function.
3857−fn chain_after_argument(
3858− kind: &ElementKind,
3860− rest: &syntax::Text,
3861− ctx: &ParseContext,
3862−) -> Option<Diagnostic> {
3863− let after = rest.raw.strip_prefix('>')?;
3864− let name_start = after.trim_start().strip_prefix('@')?;
3865− if after.len() == after.trim_start().len() {
3868− let name: String = name_start
3870− .take_while(|c| c.is_ascii_alphanumeric() || *c == '-')
3872− if ElementKind::from_name(&name).is_none() && ctx.env.function(&name).is_none() {
3875− let attr = leading_name(kind);
3876− let d = Diagnostic::warning(
3877− code::UNEXPECTED_ARGUMENT,
3880− "`{}` after @{}'s {} is text, not a chain: `>` chains after an element's name or \
3881− its [attributes], so write `@{} [{}={}] {}`",
3882− rest.raw.trim_end(),
3888− rest.raw.trim_end()
3891− .subject(rest.raw.trim_end());
3892− Some(at_attribute(d, Some(rest.span.column), ctx))
3895−/// A leading argument given twice, as the first token and as its
3896−/// attribute: `@link [href=/a] About`.
3898− kind: &ElementKind,
3899− token: &syntax::Arg,
3902− text: &syntax::Text,
3903− ctx: &ParseContext,
3905− let name = kind.name();
3906− let what = leading_name(kind);
3907− // The value as one token: quoted when it is empty or has a space in it
3908− let value = if !value.is_empty() && syntax::leading_token_len(value) == value.len() {
3911− format!("\"{}\"", value.replace('\\', "\\\\").replace('"', "\\\""))
3913− let written = if takes_no_text(kind) {
3914− format!("@{} {}", name, value)
3916− format!("@{} {} {}", name, value, text.raw)
3918− let d = Diagnostic::error(
3919− code::DUPLICATE_ATTRIBUTE,
3922− "@{} takes its first word '{}' as its {}, and it also has {}=: give it once, \
3924− name, token.raw, what, key, written
3927− .subject(token.raw.clone());
3928− at_attribute(d, Some(token.span.column), ctx)
3931−/// The attribute an element's leading argument fills, for messages.
3932−fn leading_name(kind: &ElementKind) -> &'static str {
3934− TagArg::Source => "srcset in @picture or src elsewhere",
3935− arg => arg.attribute(false).unwrap_or("argument"),
3939−/// Whether text after an element's leading argument has nowhere to go:
3940−/// an element without content (`@image`, `@source`, ...), or `@optgroup`,
3941−/// which holds only `@option` lines, so `@optgroup Citrus fruits` would
3942−/// otherwise make `Citrus` the label and drop `fruits`.
3943−fn takes_no_text(kind: &ElementKind) -> bool {
3944− kind.layout() == Layout::Void || kind.is_tag("optgroup")
3947−/// Text after the leading argument of an element without content:
3948−/// `@image logo.png Our logo`.
3949−fn after_the_leading_argument(kind: &ElementKind, token: &str, rest: &syntax::Text) -> Diagnostic {
3950− let name = kind.name();
3951− let attr = leading_name(kind);
3952− let alt = if matches!(kind, ElementKind::Image) || kind.is_tag("area") {
3953− " For a text alternative, write `alt=...`."
3957− let holds = if kind.layout() == Layout::Void {
3958− "it has no content"
3960− "it holds only the elements on the lines under it"
3962− let bare = syntax::quoted_string(token).unwrap_or(token);
3964− code::UNEXPECTED_ARGUMENT,
3967− "@{0} takes one word after its attributes, its {1} ('{2}'), and {5}, so '{3}' \
3968− would go nowhere. A value with a space in it is quoted: `\"{6} {3}\"`.{4}",
3969− name, attr, token, rest.raw, alt, holds, bare
3972− .subject(rest.raw.clone())
3975−/// The element named `name`, or an "unknown element" error that suggests
1410+fn parse_element_kind(s: &str, line_num: usize) -> Result<ElementKind, ParseError> {
3976−/// the closest element, directive or function.
1411+ if let Some(kind) = ElementKind::from_name(s) {
3977−fn parse_element_kind(
3980− ctx: &mut ParseContext,
3981−) -> Result<ElementKind, ParseError> {
3982− if let Some(kind) = ElementKind::from_name(name) {
3983 return Ok(kind);
1412 return Ok(kind);
3985− // A known name in a place it can't go: say why instead of suggesting
1414+ if let Some(hint) = removed_syntax_hint(&format!("@{}", s)) {
3986− // the name itself.
1415+ return Err(ParseError {
3987− let misplaced = if crate::ast::directive(name).is_some() {
1416+ line: line_num,
3988− Some(format!(
1417+ message: hint,
3989− "unknown element @{}: @{} is a directive, which goes at the start of its own line",
1418+ });
3992− } else if ctx.env.bundle(name).is_some() {
3994− "unknown element @{}: '{}' is an attribute bundle, used as `[${}]` \
3995− (a function is defined with `@let @{}`)",
3996− name, name, name, name
3998− } else if ctx.env.value(name).is_some() {
4000− "unknown element @{}: '{}' is a value, used as `${}` \
4001− (a function is defined with `@let @{}`)",
4002− name, name, name, name
4004− } else if ctx.namespace.contains(name) {
4005− ctx.used_functions.insert(name.to_string());
4007− "unknown element @{}: the function @{} isn't visible here. A definition is \
4008− visible from its line to the end of its block, and a function's body sees what \
4009− is defined above the function, so define @{} above this line, outside the block \
4013− } else if matches!(name, "svg" | "math" | "template") {
4015− "unknown element @{}: htmlang doesn't write <{}>; put its markup in the page with \
4020− " (or an SVG file with `@image [inline] file.svg`)"
4028− if let Some(message) = misplaced {
4029− return Err(Diagnostic::error(code::UNKNOWN_ELEMENT, line_num, message).subject(name));
4031 let all_known: Vec<&str> = ElementKind::all_names()
1420 let all_known: Vec<&str> = ElementKind::all_names()
4032− .chain(DIRECTIVES.iter().map(|d| d.name))
1421+ .chain(KNOWN_DIRECTIVES.iter().copied())
4033 .collect();
1422 .collect();
4034− // An HTML element htmlang writes under its own name (`@a` is `@link`).
1423+ let message = match suggest_closest(s, &all_known) {
4035− let written_otherwise = crate::ast::HTML_NAMES_WRITTEN_OTHERWISE
1424+ Some(closest) => format!("unknown element @{}, did you mean @{}?", s, closest),
4036− .iter()
1425+ None => format!("unknown element @{}", s),
4037− .find(|(html, _)| *html == name)
4038− .map(|(_, htmlang)| *htmlang);
4039− let closest = written_otherwise.or_else(|| suggest_closest(name, &all_known));
4040− let mut message = match (closest, written_otherwise) {
4041− (Some(closest), Some(_)) => format!(
4042− "unknown element @{}, did you mean @{}? (@{} writes <{}>)",
4043− name, closest, closest, name
4045− (Some(closest), None) => format!("unknown element @{}, did you mean @{}?", name, closest),
4046− (None, _) => format!("unknown element @{}", name),
4048− let function = suggest_fn_name(name, ctx);
1427+ Err(ParseError {
4049− if let Some(function) = &function {
1428+ line: line_num,
4050− message = format!("{}, or did you mean @{}?", message, function);
1429+ message,
1433+/// Directives and element names removed when the language was simplified,
1434+/// with what replaces each. `htmlang upgrade` rewrites all of them.
1435+const REMOVED_SYNTAX: &[(&str, &str)] = &[
1436+ ("@fn", "use `@let name $param` with an indented body"),
1437+ ("@define", "use `@let name [attributes]`"),
1438+ ("@mixin", "use `@let name [attributes]`"),
1439+ ("@unless", "use `@if not <condition>`"),
1440+ ("@for", "use `@each $i in 1..10`"),
1441+ ("@repeat", "use `@each $_ in 1..N`"),
1444+ "use `@match`, with `@let __switch [...]` inside a case for its attributes",
1446+ ("@use", "use `@include`"),
1449+ "use `@include` (a file with only definitions emits no content)",
1451+ ("@with", "use `@let alias $source`"),
1454+ "make the layout a function (`@let layout` with `@children`) and call it",
1458+ "make the layout a function (`@let layout` with `@children` and `@slot`), \
1459+ `@include` its file and call it",
1461+ ("@scope", "write the `@scope` rule in an `@style` block"),
1464+ "write the `@starting-style` rule in an `@style` block",
1466+ ("@css-property", "write an `@property` rule in an `@style` block"),
1467+ ("@lang", "use `@page [lang ...] Title`"),
1468+ ("@favicon", "use `@page [favicon ...] Title`"),
1469+ ("@canonical", "use `@page [canonical ...] Title`"),
1470+ ("@base", "use `@page [base ...] Title`"),
1471+ ("@og", "use `@meta og:NAME VALUE`"),
1472+ ("@debug", "removed: a layout needs no compile-time messages"),
1473+ ("@svg", "use `@image [inline] file.svg`"),
1474+ ("@match", "use `@if $x == a` / `@else if $x == b` / `@else`"),
1475+ ("@case", "use `@if $x == a` / `@else if $x == b` / `@else`"),
1476+ ("@default", "use `@else` in an `@if` chain"),
1477+ ("@theme", "use a `@let --name value` line per token"),
1480+ "put a `<script type=\"application/ld+json\">` in `@head`",
1482+ ("@font-face", "write the `@font-face` rule in an `@style` block"),
1485+ "write a manifest.json file and link it from `@head`",
1487+ ("@breakpoint", "write the media query in an `@style` block"),
1488+ ("@deprecated", "remove it"),
1491+ "use `@data $name dir/*.json` (each file becomes `$name.STEM.key`)",
1493+ ("@env", "use `@data $name env:NAME [default]`"),
1496+ "download the data before building and use `@data $name file.json`",
1500+ "put each locale's strings in a JSON file and use `@data $t locales/$lang.json`",
1502+ ("@defer", "remove it: the content is already in the page"),
1503+ ("@keyframes", "write the CSS `@keyframes` rule in `@style`"),
1504+ ("@log", "removed: a layout needs no compile-time messages"),
1505+ ("@warn", "removed: a layout needs no compile-time messages"),
1506+ ("@assert", "removed: a layout needs no compile-time checks"),
1509+ "use `@let`: an `@style` block in a function body is scoped to it",
1511+ ("@col", "use `@el`"),
1512+ ("@p", "use `@paragraph`"),
1513+ ("@img", "use `@image`"),
1514+ ("@btn", "use `@button`"),
1515+ ("@divider", "use `@hr`"),
1516+ ("@opt", "use `@option`"),
1519+/// Attributes that became standard-library bundles or plain CSS.
1520+fn removed_attribute_hint(name: &str) -> Option<&'static str> {
1522+ "skeleton" => Some("use the `$skeleton` bundle"),
1523+ "no-scrollbar" => Some("use the `$no-scrollbar` bundle"),
1524+ "gradient" => Some("use `background linear-gradient(...)`"),
1525+ "animate" => Some("use `animation`"),
1526+ "inset-area" => Some("use `position-area`"),
1527+ "gap-x" => Some("use `column-gap`"),
1528+ "gap-y" => Some("use `row-gap`"),
1529+ "shadow" => Some("use `box-shadow`"),
1530+ "blur" => Some("use `filter blur(...)`"),
1531+ "backdrop-blur" => Some("use `backdrop-filter blur(...)`"),
1532+ "truncate" => Some("use the `$truncate` bundle"),
1533+ "critical" => Some("remove it"),
1534+ "grid" => Some("use `@grid`, or `display grid`"),
1535+ "bold" => Some("use `font-weight bold`"),
1536+ "italic" => Some("use `font-style italic`"),
1537+ "underline" => Some("use `text-decoration underline`"),
1538+ "size" => Some("use `font-size`"),
1539+ "rounded" => Some("use `border-radius`"),
1540+ "hidden" => Some("use `display none`"),
1541+ "padding-x" => Some("use `padding-inline`"),
1542+ "padding-y" => Some("use `padding-block`"),
1543+ "margin-x" => Some("use `margin-inline`"),
1544+ "margin-y" => Some("use `margin-block`"),
4052− Err(Diagnostic::error(code::UNKNOWN_ELEMENT, line_num, message)
1547+}
4053− .subject(name)
1548+
4054− .suggest(closest.map(str::to_string).or(function)))
1549+/// If `content` starts with removed syntax, the error message for it.
1550+fn removed_syntax_hint(content: &str) -> Option<String> {
1551+ let trimmed = content.trim_start();
1552+ REMOVED_SYNTAX.iter().find_map(|(name, replacement)| {
1553+ let rest = trimmed.strip_prefix(name)?;
1554+ if !(rest.is_empty() || rest.starts_with([' ', '['])) {
1558+ "`{}` was removed: {} (run `htmlang upgrade` to rewrite it automatically)",
4057/// Format include/import stack as a readable chain for error messages.
1564/// Format include/import stack as a readable chain for error messages.
@@ -4122,37 +1629,34 @@ fn suggest_closest<'a>(input: &str, candidates: &[&'a str]) -> Option<&'a str> {
4125−/// Suggest the closest user-defined function name for typos, from the
1632+/// Suggest the closest user-defined function name for typos.
4126−/// functions defined so far and those defined anywhere in the file.
4127fn suggest_fn_name(input: &str, ctx: &ParseContext) -> Option<String> {
1633fn suggest_fn_name(input: &str, ctx: &ParseContext) -> Option<String> {
4128 let input_chars: Vec<char> = input.chars().collect();
1634 let input_chars: Vec<char> = input.chars().collect();
4129 let max_allowed = 2usize.min(input_chars.len().saturating_sub(1));
1635 let max_allowed = 2usize.min(input_chars.len().saturating_sub(1));
4130− let mut best: Option<(usize, &String)> = None;
1636+ let mut best: Option<String> = None;
4131− let visible: Vec<&String> = ctx.defined_functions.keys().collect();
1637+ let mut best_dist = usize::MAX;
4132− for name in visible.into_iter().chain(ctx.namespace.iter()) {
1638+ for name in ctx.functions.keys() {
4133 let nlen = name.chars().count();
1639 let nlen = name.chars().count();
4134 if nlen.abs_diff(input_chars.len()) > max_allowed {
1640 if nlen.abs_diff(input_chars.len()) > max_allowed {
4135 continue;
1641 continue;
4137 let name_chars: Vec<char> = name.chars().collect();
1643 let name_chars: Vec<char> = name.chars().collect();
4138 let dist = levenshtein_bounded(&input_chars, &name_chars, max_allowed);
1644 let dist = levenshtein_bounded(&input_chars, &name_chars, max_allowed);
4139− if dist <= max_allowed && best.is_none_or(|b| (dist, name) < b) {
1645+ if dist < best_dist && dist <= max_allowed {
4140− best = Some((dist, name));
1646+ best_dist = dist;
1647+ best = Some(name.clone());
4143− best.map(|(_, name)| name.clone())
1650+ best
4146/// Suggest the closest variable name for undefined `$var` references.
1653/// Suggest the closest variable name for undefined `$var` references.
4147−fn suggest_var_name(input: &str, vars: &[&str]) -> Option<String> {
1654+fn suggest_var_name(input: &str, vars: &HashMap<String, String>) -> Option<String> {
4148 let input_chars: Vec<char> = input.chars().collect();
1655 let input_chars: Vec<char> = input.chars().collect();
4149 let max_allowed = 2usize.min(input_chars.len().saturating_sub(1));
1656 let max_allowed = 2usize.min(input_chars.len().saturating_sub(1));
4150 let mut best: Option<String> = None;
1657 let mut best: Option<String> = None;
4151 let mut best_dist = usize::MAX;
1658 let mut best_dist = usize::MAX;
4152− let mut vars = vars.to_vec();
1659+ for name in vars.keys().filter(|k| !k.ends_with('#')) {
4153− // The same answer every time, whatever the order of the names
4154− vars.sort_unstable();
4156 let nlen = name.chars().count();
1660 let nlen = name.chars().count();
4157 if nlen.abs_diff(input_chars.len()) > max_allowed {
1661 if nlen.abs_diff(input_chars.len()) > max_allowed {
4158 continue;
1662 continue;
@@ -4161,1988 +1665,1019 @@ fn suggest_var_name(input: &str, vars: &[&str]) -> Option<String> {
4161 let dist = levenshtein_bounded(&input_chars, &name_chars, max_allowed);
1665 let dist = levenshtein_bounded(&input_chars, &name_chars, max_allowed);
4162 if dist < best_dist && dist <= max_allowed {
1666 if dist < best_dist && dist <= max_allowed {
4163 best_dist = dist;
1667 best_dist = dist;
4164− best = Some(name.to_string());
1668+ best = Some(name.clone());
4170−// ---------------------------------------------------------------------------
1674+/// Check for undefined `$var` references and return "did you mean?" diagnostics.
4171−// Attribute parsing
1675+/// `indent` is the line's leading whitespace, which `input` has had trimmed;
4172−// ---------------------------------------------------------------------------
1676+/// reported columns and source lines include it.
4173−
1677+fn check_undefined_vars(
4174−/// The quoted strings of a CSS value, without their quotes.
1678+ input: &str,
4175−fn css_strings(value: &str) -> Vec<&str> {
1679+ vars: &HashMap<String, String>,
4176− let mut strings = Vec::new();
1680+ line_num: usize,
4177− let mut start = None;
1681+ indent: usize,
4178− let mut escaped = false;
1682+) -> Vec<Diagnostic> {
4179− for (i, c) in value.char_indices() {
1683+ let mut warnings = Vec::new();
4180− match (c, start) {
1684+ if !input.contains('$') {
4181− _ if escaped => escaped = false,
1685+ return warnings;
4182− ('\\', Some(_)) => escaped = true,
1686+ }
4183− ('"', None) => start = Some(i + 1),
1687+ let chars: Vec<char> = input.chars().collect();
4184− ('"', Some(from)) => {
1688+ let mut i = 0;
4185− strings.push(&value[from..i]);
1689+ while i < chars.len() {
4186− start = None;
1690+ if chars[i] == '$'
1691+ && i + 1 < chars.len()
1692+ && (chars[i + 1].is_alphanumeric() || chars[i + 1] == '_' || chars[i + 1] == '-')
1696+ let mut end = start;
1697+ while end < chars.len()
1698+ && (chars[end].is_alphanumeric()
1699+ || chars[end] == '-'
1700+ || chars[end] == '_'
1701+ || chars[end] == '.')
4188− _ => {}
1705+ while end > start && chars[end - 1] == '.' {
1708+ let name: String = chars[start..end].iter().collect();
1709+ if !name.is_empty()
1710+ && !vars.contains_key(&name)
1711+ && let Some(closest) = suggest_var_name(&name, vars)
1713+ warnings.push(Diagnostic {
1715+ column: Some(indent + col),
1717+ "undefined variable '${}', did you mean '${}'?",
1720+ severity: Severity::Warning,
1721+ source_line: Some(format!("{}{}", " ".repeat(indent), input)),
4191− strings
1729+ warnings
4194−/// An `if(...)` in a CSS value that isn't CSS's if(): CSS writes each
1732+// ---------------------------------------------------------------------------
4195−/// branch `CONDITION: VALUE`, so an if() without a `:` is something else.
1733+// Attribute parsing
4196−/// Quoted CSS strings are text, not calls.
1734+// ---------------------------------------------------------------------------
4197−fn not_css_if(value: &str) -> Option<&str> {
1735+
4198− let mut quote = None;
1736+/// Attributes that expect purely numeric values (px-based) or values with CSS units.
4199− let mut prev = None;
1737+const NUMERIC_ATTRS: &[&str] = &[
4200− let mut chars = value.char_indices();
1738+ "spacing",
4201− while let Some((at, c)) = chars.next() {
1739+ "gap",
4202− match quote {
1740+ "padding",
4203− Some(_) if c == '\\' => {
1741+ "padding-top",
4204− chars.next();
1742+ "padding-bottom",
1760+const CSS_UNIT_SUFFIXES: &[&str] = &[
1761+ "px", "%", "rem", "em", "vh", "vw", "vmin", "vmax", "dvh", "svh", "lvh", "ch", "ex", "cm",
1762+ "mm", "in", "pt", "pc", "fr",
1765+fn has_css_unit(value: &str) -> bool {
1766+ CSS_UNIT_SUFFIXES.iter().any(|u| value.ends_with(u))
1767+ || value.starts_with("var(")
1768+ || value.starts_with("calc(")
1769+ || value.starts_with("clamp(")
1770+ || value.starts_with("min(")
1771+ || value.starts_with("max(")
1774+/// Attributes that accept numeric OR keyword values.
1775+const NUMERIC_OR_KEYWORD_ATTRS: &[&str] = &["width", "height"];
1776+const SIZE_KEYWORDS: &[&str] = &["fill", "shrink"];
1778+fn validate_attr_value(attr: &Attribute, line_num: usize, ctx: &mut ParseContext) {
1779+ let base_key = crate::vocab::base_attribute(attr.key.as_str());
1781+ if let Some(val) = &attr.value {
1782+ if NUMERIC_ATTRS.contains(&base_key) {
1783+ // All space-separated parts must be numeric or have a CSS unit
1784+ for part in val.split_whitespace() {
1785+ if part.parse::<f64>().is_err() && !has_css_unit(part) {
1786+ ctx.diagnostics.push(Diagnostic {
1790+ "'{}' expects a numeric value (with optional unit), got '{}'",
1793+ severity: Severity::Warning,
4206− Some(q) if c == q => quote = None,
1799+ } else if NUMERIC_OR_KEYWORD_ATTRS.contains(&base_key) {
4207− Some(_) => {}
1800+ let is_keyword = SIZE_KEYWORDS.contains(&val.as_str());
4208− None if matches!(c, '"' | '\'') => quote = Some(c),
1801+ let is_numeric = val.parse::<f64>().is_ok();
4209− None => {
1802+ let has_unit = has_css_unit(val);
4210− let word_before =
1803+ if !is_keyword && !is_numeric && !has_unit {
4211− prev.is_some_and(|p: char| p.is_alphanumeric() || matches!(p, '-' | '_'));
1804+ ctx.diagnostics.push(Diagnostic {
4212− if !word_before && value[at..].starts_with("if(") {
1805+ line: line_num,
4213− let mut depth = 0;
1806+ column: None,
4214− let close = value[at + 2..].char_indices().find_map(|(i, c)| {
1807+ message: format!(
4215− match c {
1808+ "'{}' expects a number or one of [{}], got '{}'",
4216− '(' => depth += 1,
1809+ attr.key,
4217− ')' => depth -= 1,
1810+ SIZE_KEYWORDS.join(", "),
4220− (depth == 0).then_some(at + 2 + i)
1813+ severity: Severity::Warning,
1817+ } else if base_key == "opacity" {
1818+ if let Ok(v) = val.parse::<f64>() {
1819+ if !(0.0..=1.0).contains(&v) {
1820+ ctx.diagnostics.push(Diagnostic {
1823+ message: format!("'opacity' should be between 0 and 1, got '{}'", val),
1824+ severity: Severity::Warning,
4222− let end = close.map_or(value.len(), |c| c + 1);
4223− if !value[at + 3..end].contains(':') {
4224− return Some(&value[at..end]);
1829+ ctx.diagnostics.push(Diagnostic {
1832+ message: format!("'opacity' expects a numeric value, got '{}'", val),
1833+ severity: Severity::Warning,
4228− }
1837+ } else if base_key == "z-index" {
4229− prev = Some(c);
1838+ if val.parse::<i32>().is_err() {
4230− }
1839+ ctx.diagnostics.push(Diagnostic {
4231− None
1840+ line: line_num,
4232−}
1841+ column: None,
4233−
1842+ message: format!("'z-index' expects an integer, got '{}'", val),
4234−/// Why a CSS value can't be written into a rule as it is, whatever it
1843+ severity: Severity::Warning,
4235−/// means: a `;` (outside parentheses, where CSS's own `if()` uses it), a
1844+ source_line: None,
4236−/// `{` or a `}` would end the declaration or the rule, and an unclosed
1845+ });
4237−/// quote or parenthesis would run on into the rules after it. Quoted
4238−/// strings are text, and a backslash escapes the character after it, as
4239−/// in CSS. A `</style` anywhere, even in a string, would end the page's
4240−/// `<style>` element and start HTML.
4241−fn css_breakout(value: &str) -> Option<&'static str> {
4242− if value.to_ascii_lowercase().contains("</style") {
4243− return Some("a `</style`, which would end the page's style element");
4245− let mut quote = None;
4246− let mut depth = 0usize;
4247− let mut chars = value.chars();
4248− while let Some(c) = chars.next() {
4253− (Some(q), c) if c == q => quote = None,
1847+ } else if base_key == "display" {
4254− (Some(_), _) => {}
1848+ const DISPLAY_VALUES: &[&str] = &[
4255− (None, '"' | '\'') => quote = Some(c),
1849+ "none",
4256− (None, '(') => depth += 1,
1850+ "block",
4257− (None, ')') if depth == 0 => return Some("a `)` that closes nothing"),
1851+ "inline",
4258− (None, ')') => depth -= 1,
1852+ "inline-block",
4259− (None, ';') if depth == 0 => return Some("a `;`, which would end the declaration"),
1853+ "flex",
4260− (None, '{' | '}') => return Some("a `{` or `}`, which would end the CSS rule"),
1854+ "inline-flex",
4261− _ => {}
1855+ "grid",
4262− }
1856+ "inline-grid",
4264− match (quote, depth) {
1858+ "table-row",
4265− (Some('"'), _) => Some("a `\"` that isn't closed"),
1859+ "table-cell",
4266− (Some(_), _) => Some("a `'` that isn't closed"),
1860+ "contents",
4267− (None, 0) => None,
1861+ "flow-root",
4268− (None, _) => Some("a `(` that isn't closed"),
1862+ "list-item",
4270−}
1864+ if !DISPLAY_VALUES.contains(&val.as_str()) && !val.starts_with("var(") {
4271−
1865+ let suggestion = suggest_closest(val, DISPLAY_VALUES);
4272−/// The hex colors of a CSS value that don't have 3, 4, 6 or 8 hex
1866+ let msg = match suggestion {
4273−/// digits. A `#` word in a CSS value is a color, except inside `url(...)`
1867+ Some(s) => format!("unknown display value '{}', did you mean '{}'?", val, s),
4274−/// and quoted strings.
1868+ None => format!("unknown display value '{}'", val),
4275−fn bad_hex_colors(value: &str) -> Vec<&str> {
1869+ };
4276− let mut bad = Vec::new();
1870+ ctx.diagnostics.push(Diagnostic {
4277− let mut quote = None;
1871+ line: line_num,
4278− let mut in_url = 0usize;
1872+ column: None,
4279− let mut depth = 0usize;
1873+ message: msg,
4280− let mut chars = value.char_indices().peekable();
1874+ severity: Severity::Warning,
4281− while let Some((at, c)) = chars.next() {
1875+ source_line: None,
4282− match (quote, c) {
1876+ });
4286− (Some(q), c) if c == q => quote = None,
1878+ } else if base_key == "position" {
4287− (Some(_), _) => {}
1879+ const POSITION_VALUES: &[&str] = &["static", "relative", "absolute", "fixed", "sticky"];
4288− (None, '"' | '\'') => quote = Some(c),
1880+ if !POSITION_VALUES.contains(&val.as_str()) && !val.starts_with("var(") {
4289− (None, '(') => {
1881+ let suggestion = suggest_closest(val, POSITION_VALUES);
4290− depth += 1;
1882+ let msg = match suggestion {
4291− if value[..at].ends_with("url") && in_url == 0 {
1883+ Some(s) => format!("unknown position value '{}', did you mean '{}'?", val, s),
4292− in_url = depth;
1884+ None => format!("unknown position value '{}'", val),
1886+ ctx.diagnostics.push(Diagnostic {
1890+ severity: Severity::Warning,
4295− (None, ')') => {
1894+ } else if base_key == "overflow" || base_key == "overflow-x" || base_key == "overflow-y" {
4296− if in_url == depth {
1895+ const OVERFLOW_VALUES: &[&str] = &["visible", "hidden", "scroll", "auto", "clip"];
4297− in_url = 0;
1896+ if !OVERFLOW_VALUES.contains(&val.as_str()) && !val.starts_with("var(") {
4298− }
1897+ let suggestion = suggest_closest(val, OVERFLOW_VALUES);
4299− depth = depth.saturating_sub(1);
1898+ let msg = match suggestion {
1899+ Some(s) => format!("unknown overflow value '{}', did you mean '{}'?", val, s),
1900+ None => format!("unknown overflow value '{}'", val),
1902+ ctx.diagnostics.push(Diagnostic {
1906+ severity: Severity::Warning,
4301− (None, '#') if in_url == 0 => {
1910+ } else if base_key == "text-align" {
4302− let end = value[at + 1..]
1911+ const TEXT_ALIGN_VALUES: &[&str] =
4303− .find(|c: char| !(c.is_alphanumeric() || c == '-' || c == '_'))
1912+ &["left", "right", "center", "justify", "start", "end"];
4304− .map_or(value.len(), |n| at + 1 + n);
1913+ if !TEXT_ALIGN_VALUES.contains(&val.as_str()) && !val.starts_with("var(") {
4305− let hex = &value[at + 1..end];
1914+ let suggestion = suggest_closest(val, TEXT_ALIGN_VALUES);
4306− if !(matches!(hex.len(), 3 | 4 | 6 | 8)
1915+ let msg = match suggestion {
4307− && hex.chars().all(|c| c.is_ascii_hexdigit()))
1916+ Some(s) => format!("unknown text-align value '{}', did you mean '{}'?", val, s),
4308− {
1917+ None => format!("unknown text-align value '{}'", val),
4309− bad.push(&value[at..end]);
1918+ };
4310− }
1919+ ctx.diagnostics.push(Diagnostic {
1923+ severity: Severity::Warning,
4312− _ => {}
1927+ } else if base_key == "cursor" {
4313− }
1928+ const CURSOR_VALUES: &[&str] = &[
4315− bad
1930+ "default",
4318−/// A diagnostic about an attribute, with its column and source line when
1933+ "wait",
4319−/// it is on the line being evaluated.
1934+ "text",
4320−fn at_attribute(diagnostic: Diagnostic, column: Option<usize>, ctx: &ParseContext) -> Diagnostic {
1935+ "move",
4321− match (&ctx.current_source, column) {
1936+ "not-allowed",
4322− ((current, Some(text)), Some(column)) if *current == diagnostic.line => {
1937+ "crosshair",
4323− diagnostic.column(column).source(text.clone())
1938+ "grab",
4325− _ => diagnostic,
1940+ "help",
4327−}
1942+ "col-resize",
4329−/// Check a style's value. Values go to the CSS as written, so only what
1944+ "n-resize",
4330−/// can't be wrong in any CSS is checked: a value that would break out of
1945+ "s-resize",
4331−/// its rule is an error (and it is left out); a hex color without 3, 4, 6
1946+ "e-resize",
4332−/// or 8 digits, an `if()` that isn't CSS's and a quoted font stack are
1947+ "w-resize",
4333−/// warnings. Returns whether the value can be written.
1948+ "zoom-in",
4334−fn check_css_value(
1949+ "zoom-out",
4335− attr: &Attribute,
1950+ "context-menu",
4336− base: &str,
1951+ "cell",
4337− line: usize,
1952+ "copy",
4338− column: Option<usize>,
1953+ "alias",
4339− ctx: &mut ParseContext,
1954+ "no-drop",
4341− let Some(value) = &attr.value else {
1956+ if !CURSOR_VALUES.contains(&val.as_str())
4342− return true;
1957+ && !val.starts_with("url(")
4343− };
1958+ && !val.starts_with("var(")
4344− if let Some(reason) = css_breakout(value) {
4345− let diagnostic = Diagnostic::error(
4346− code::INVALID_VALUE,
4349− "the value of '{}' has {}: `{}` can't be written into the page's CSS",
4350− attr.key, reason, value
4353− .subject(value.as_str());
4354− ctx.diagnostics.push(at_attribute(diagnostic, column, ctx));
4357− if crate::vocab::is_custom_property(base) {
4361− let warn = |ctx: &mut ParseContext, diagnostic: Diagnostic| {
4362− let diagnostic = at_attribute(diagnostic, column, ctx);
4363− ctx.diagnostics.push(diagnostic);
4365− // In CSS, a quoted font-family is one family, commas and all
4366− if base == "font-family"
4367− && let Some(family) = css_strings(value).into_iter().find(|s| s.contains(','))
4372− .collect::<Vec<_>>()
4376− Diagnostic::warning(
4377− code::INVALID_VALUE,
4380− "font-family \"{}\" is one family, whose name has a comma in it: \
4381− for a font stack, write `font-family {}`",
4385− .subject(format!("\"{}\"", family))
4386− .suggest(Some(stack)),
4389− if let Some(call) = not_css_if(value) {
4392− Diagnostic::warning(
4393− code::INVALID_VALUE,
4396− "'{}' is not CSS's if(), whose branches are written \
4397− `if(CONDITION: VALUE; else: VALUE)`",
4404− for color in bad_hex_colors(value) {
4407− Diagnostic::warning(
4408− code::INVALID_COLOR,
4411− "invalid hex color '{}': a hex color has 3, 4, 6 or 8 hex digits",
4421−/// An unknown prefix: the message, the text it is about, and what to write
4422−/// instead, when something is close enough.
4423−struct PrefixProblem {
4426− suggestion: Option<String>,
4429−/// What is wrong with the prefix `rest` starts with, when the known
4430−/// prefixes are already split off it and what is left still starts with
4431−/// one: a word and a `:` (`hovr:`), or a word and a parenthesised argument
4432−/// and a `:` (`nth-chld(2):`). Selector prefixes are CSS's pseudo-classes
4433−/// and pseudo-elements under their CSS names, so an unknown one gets the
4434−/// closest name as a suggestion. Only names with the same first letter are
4435−/// suggested: `odd:` is two edits from `md:`, which it doesn't mean.
4436−fn unknown_prefix(rest: &str) -> Option<PrefixProblem> {
4437− use crate::vocab::{self, Pseudo};
4438− let name_len = rest.find(|c: char| !(c.is_ascii_alphanumeric() || c == '-'))?;
4439− let name = &rest[..name_len];
4440− if name.is_empty() {
4443− if rest[name_len..].starts_with('(') {
4444− // `name(...):`: a pseudo-class with an argument
4445− let close = vocab::closing_paren(rest, name_len)?;
4446− if !rest[close + 1..].starts_with(':') {
4449− let written = &rest[..close + 2];
4450− if matches!(vocab::pseudo(name), Some(Pseudo::Class | Pseudo::Element)) {
4451− let bare = format!("{}:", name);
4452− return Some(PrefixProblem {
4454− "'{}': `{}` takes no argument: write `{}`",
4456− vocab::pseudo_selector(&bare).unwrap_or_default(),
4459− subject: written.to_string(),
4460− suggestion: Some(bare),
4463− let functional: Vec<&str> = vocab::functional_pseudos()
4465− .filter(|p| p.chars().next() == name.chars().next())
4467− let suggestion = suggest_closest(name, &functional)
4468− .filter(|&closest| closest != name)
4469− .map(|closest| format!("{}(", closest));
4470− let written = format!("{}(", name);
4471− let message = match &suggestion {
4472− Some(closest) => format!("unknown prefix '{}', did you mean '{}'?", written, closest),
4473− None => format!("unknown prefix '{}'", written),
4475− return Some(PrefixProblem {
4481− if !rest[name_len..].starts_with(':') {
4484− let written = &rest[..name_len + 1];
4485− // `has:`: its argument is missing
4486− if vocab::pseudo(name) == Some(Pseudo::Function) {
4487− return Some(PrefixProblem {
4489− "'{}': `:{}()` takes an argument, in parentheses, as in CSS: `{}(...):`",
4490− written, name, name
4492− subject: written.to_string(),
4496− let prefixes = vocab::all_prefixes();
4497− let candidates: Vec<&str> = prefixes
4499− .map(String::as_str)
4500− .filter(|p| p.chars().next() == written.chars().next())
4502− // The closest name that starts with the same letter (`hvoer:` →
4503− // `hover:`), else the first that starts with the word written and a `-`
4504− // (`first:` → `first-child:`)
4505− let suggestion = suggest_closest(written, &candidates)
4507− let longer = format!("{}-", name);
4508− candidates.iter().copied().find(|p| p.starts_with(&longer))
4510− .filter(|&closest| closest != written)
4511− .map(str::to_string);
4512− let message = match &suggestion {
4513− Some(closest) => format!("unknown prefix '{}', did you mean '{}'?", written, closest),
4514− None => format!("unknown prefix '{}'", written),
4516− Some(PrefixProblem {
4518− subject: written.to_string(),
4523−/// Check an attribute's element prefix (`@td:padding 8`), when it has one:
4524−/// it names a built-in element that has an HTML tag of its own (not a
4525−/// function, and not `@el`, whose `<div>` other elements write too), there
4526−/// is one, not with `children:`, and what it styles is a CSS property, not
4527−/// one of htmlang's words, which compile against each element's layout and
4528−/// its parent's. Returns false, after reporting, when the attribute can't
4530−fn check_element_prefixes(
4535− column: Option<usize>,
4536− ctx: &mut ParseContext,
4538− use crate::ast::ElementKind;
4540− let elements: Vec<&str> = prefixes
4543− .filter(|p| vocab::element_prefix(p).is_some())
4545− let Some(&prefix) = elements.first() else {
4548− let fail = |ctx: &mut ParseContext,
4549− code: &'static str,
4552− suggestion: Option<String>| {
4553− let diagnostic = Diagnostic::error(code, line, message)
4555− .suggest(suggestion);
4556− let diagnostic = at_attribute(diagnostic, column, ctx);
4557− ctx.diagnostics.push(diagnostic);
4560− let name = vocab::element_prefix(prefix).unwrap_or_default();
4561− if is_function(name, ctx) {
4564− code::INVALID_PREFIX,
4566− "'{}': @{} is a function, and `{}` would pick elements out by their HTML tag, \
4567− which a function doesn't have: style what @{} writes in its body, or pass it \
4569− attr.key, name, prefix, name
4575− match ElementKind::from_name(name) {
4577− let own: Vec<&str> = ElementKind::all_names()
4578− .filter(|n| ElementKind::from_name(n).is_some_and(|k| k.own_tag().is_some()))
4580− // An HTML name htmlang writes under another (`@a:` is `@link:`)
4581− let (written_otherwise, shared) = match crate::ast::HTML_NAMES_WRITTEN_OTHERWISE
4583− .find(|(html, _)| *html == name)
4585− Some((_, htmlang)) if own.contains(htmlang) => (Some(*htmlang), false),
1960+ let suggestion = suggest_closest(val, CURSOR_VALUES);
4586− Some(_) => (None, true),
1961+ let msg = match suggestion {
4587− None => (None, false),
1962+ Some(s) => format!("unknown cursor value '{}', did you mean '{}'?", val, s),
4588− };
1963+ None => format!("unknown cursor value '{}'", val),
4589− // `@each:`, `@markdown:`: a directive, which is no element
1964+ };
4590− if crate::ast::directive(name).is_some() {
1965+ ctx.diagnostics.push(Diagnostic {
4591− return fail(
1966+ line: line_num,
4592− ctx,
1967+ column: None,
4593− code::UNKNOWN_PREFIX,
1968+ message: msg,
4594− format!(
1969+ severity: Severity::Warning,
4595− "unknown element @{} in '{}': @{} is a directive, and an element \
1970+ source_line: None,
4596− prefix names an element with an HTML tag of its own, such as `@td:`",
1971+ });
4603− // `@div:`, `@span:`: several elements write it
1973+ } else if base_key == "font-weight" {
4604− if shared {
1974+ const WEIGHT_VALUES: &[&str] = &[
4605− return fail(
1975+ "normal", "bold", "bolder", "lighter", "100", "200", "300", "400", "500", "600",
4606− ctx,
1976+ "700", "800", "900",
4607− code::UNKNOWN_PREFIX,
1977+ ];
4608− format!(
1978+ if !WEIGHT_VALUES.contains(&val.as_str()) && !val.starts_with("var(") {
4609− "unknown element @{} in '{}': htmlang writes <{}> for several \
1979+ ctx.diagnostics.push(Diagnostic {
4610− elements, so no element prefix picks it out",
1980+ line: line_num,
4611− name, prefix, name
1981+ column: None,
1983+ "'font-weight' expects a weight keyword or number 100-900, got '{}'",
4613− prefix,
1986+ severity: Severity::Warning,
4614− None,
1987+ source_line: None,
4617− // A name with the same first letter first (`@tdd:` is `@td:`)
1990+ } else if base_key == "color" || base_key == "background" {
4618− let same_letter: Vec<&str> = own
1991+ // Validate named CSS colors (only if not hex, rgb, hsl, var, etc.)
4619− .iter()
1992+ if !val.starts_with('#')
4620− .copied()
1993+ && !val.starts_with("rgb")
4621− .filter(|n| n.chars().next() == name.chars().next())
1994+ && !val.starts_with("hsl")
4622− .collect();
1995+ && !val.starts_with("var(")
4623− let closest = written_otherwise
1996+ && !val.starts_with("linear-gradient")
4624− .or_else(|| suggest_closest(name, &same_letter))
1997+ && !val.starts_with("radial-gradient")
4625− .or_else(|| suggest_closest(name, &own));
1998+ && !val.starts_with("conic-gradient")
4626− let message = match (closest, written_otherwise) {
1999+ && !val.starts_with("oklch")
4627− (Some(closest), Some(_)) => format!(
2000+ && !val.starts_with("oklab")
4628− "unknown element @{} in '{}', did you mean '@{}:'? (@{} writes <{}>)",
2001+ && !val.starts_with("color(")
4629− name, prefix, closest, closest, name
2002+ && !val.starts_with("light-dark(")
4630− ),
2003+ && !val.contains("url(")
4631− (Some(closest), None) => format!(
2004+ && !val.contains(' ')
4632− "unknown element @{} in '{}', did you mean '@{}:'?",
2005+ // skip shorthand multi-value
4633− name, prefix, closest
2006+ {
4634− ),
2007+ const NAMED_COLORS: &[&str] = &[
4635− (None, _) => format!("unknown element @{} in '{}'", name, prefix),
2008+ "transparent",
4636− };
2009+ "currentcolor",
4637− let suggestion = closest.map(|c| format!("@{}:", c));
2010+ "inherit",
4638− fail(ctx, code::UNKNOWN_PREFIX, message, prefix, suggestion)
2011+ "initial",
4640− Some(kind) if kind.own_tag().is_none() => {
2013+ "black",
4641− let reason = match kind.tag() {
2014+ "white",
4642− None => format!(
2015+ "red",
4643− "@{} writes no element of its own, so there is nothing for `{}` to style",
2016+ "green",
4644− name, prefix
2017+ "blue",
4646− Some(_) if kind.is_verbatim() => {
2019+ "orange",
4647− format!("@{} isn't shown, so there is nothing to style", name)
2020+ "purple",
4649− Some("span") => format!(
2022+ "brown",
4650− "@{} writes a <span>, as every line of text in a row or column does, so \
2023+ "gray",
4651− `{}` can't pick it out",
2024+ "grey",
4652− name, prefix
2025+ "cyan",
4654− Some(tag) => {
2027+ "lime",
4655− let others: Vec<String> = ElementKind::all_names()
2028+ "olive",
4656− .filter(|n| {
2029+ "navy",
4657− *n != name
2030+ "teal",
4658− && ElementKind::from_name(n).and_then(|k| k.tag()) == Some(tag)
2031+ "aqua",
4660− .map(|n| format!("@{}", n))
2033+ "maroon",
4661− .collect();
2034+ "silver",
4662− let others = match others.split_last() {
2035+ "coral",
4663− Some((last, [])) => last.clone(),
2036+ "salmon",
4664− Some((last, rest)) => format!("{} and {}", rest.join(", "), last),
2037+ "tomato",
4665− None => String::new(),
2038+ "crimson",
2076+ if !NAMED_COLORS.contains(&val.to_lowercase().as_str()) {
2077+ let lower = val.to_lowercase();
2078+ let suggestion = suggest_closest(&lower, NAMED_COLORS);
2079+ let msg = match suggestion {
2080+ Some(s) => format!("unknown color '{}', did you mean '{}'?", val, s),
2081+ None => format!("unknown color '{}'", val),
4667− format!(
2083+ ctx.diagnostics.push(Diagnostic {
4668− "@{} writes a <{}>, as {} do, so `{}` can't pick it out",
2084+ line: line_num,
4669− name, tag, others, prefix
2085+ column: None,
4670− )
2086+ message: msg,
2087+ severity: Severity::Warning,
4675− code::INVALID_PREFIX,
4677− "'{}': {}. Give those elements their styles themselves, or a bundle \
4678− (`@let name [...]`, used as `[$name]`)",
4685− Some(_) if elements.len() > 1 => fail(
4687− code::INVALID_PREFIX,
4689− "'{}': a style takes one element prefix, which styles every such element \
4690− inside this one, at any depth",
4696− Some(_) if prefixes.contains(&vocab::CHILDREN) => fail(
4698− code::INVALID_PREFIX,
4700− "'{}': `children:` and `{}` each say which elements the style is for: write \
4707− Some(_) if vocab::is_htmlang_word(base, attr.value.as_deref()) => {
4708− let value = attr.value.as_deref().map(str::trim);
4709− let css = match (base, value) {
4710− ("spacing", _) => " (`gap`)",
4711− ("wrap", _) => " (`flex-wrap wrap`)",
4712− ("grid-cols", _) => " (`grid-template-columns`)",
4713− ("grid-rows", _) => " (`grid-template-rows`)",
4714− ("col-span", _) => " (`grid-column span N`)",
4715− ("row-span", _) => " (`grid-row span N`)",
4716− ("width", Some("fill")) => " (`flex 1` in a row, `width 100%` otherwise)",
4717− ("height", Some("fill")) => " (`flex 1` in a column, `height 100%` otherwise)",
4718− ("width", _) => " (`flex-shrink 0` in a row, `width fit-content` otherwise)",
4719− ("height", _) => " (`flex-shrink 0` in a column, `height fit-content` otherwise)",
4720− ("center-x", _) => " (`margin-inline auto`)",
4721− ("center-y", _) => " (`margin-block auto`)",
4724− let word = match value {
4725− Some(v) if matches!(base, "width" | "height") => format!("{} {}", base, v),
4726− _ => base.to_string(),
4730− code::INVALID_PREFIX,
4732− "'{}': `{}` is one of htmlang's layout words, which compile against each \
4733− element's layout and its parent's, and `{}` styles elements whose \
4734− parents it doesn't know: write `{}` on the elements themselves, or the \
4736− attr.key, word, prefix, word, css
4746−/// Check an attribute's prefixes: each is known, their selector prefixes
2096+fn parse_attr_brackets(
4747−/// read left to right with a pseudo-element (`before:`) last, the argument
2097+ input: &str,
4748−/// of `has(...)` or `nth-child(...)` can be written into the CSS, and a word that
2098+ line_num: usize,
4749−/// places an element in its parent (`width fill`, `center-x`, `align-*`)
4750−/// isn't under `children:`, whose styles go on the children. Media,
4751−/// container and width prefixes go anywhere. Returns false, after
4752−/// reporting, when the attribute can't be written.
4756− column: Option<usize>,
4757 ctx: &mut ParseContext,
2099 ctx: &mut ParseContext,
4758−) -> bool {
2100+) -> Result<(Vec<Attribute>, String), ParseError> {
4759− use crate::vocab;
2101+ parse_attr_brackets_inner(input, line_num, ctx, true)
4760− let (prefixes, base) = vocab::split_prefixes(&attr.key);
2102+}
4762− |ctx: &mut ParseContext, message: String, subject: &str, suggestion: Option<String>| {
4763− let diagnostic = Diagnostic::error(code::INVALID_PREFIX, line, message)
4765− .suggest(suggestion);
4766− let diagnostic = at_attribute(diagnostic, column, ctx);
4767− ctx.diagnostics.push(diagnostic);
4771− if let Some(problem) = unknown_prefix(base) {
2104+fn parse_attr_brackets_no_validate(
4772− let diagnostic = Diagnostic::error(code::UNKNOWN_PREFIX, line, problem.message)
2105+ input: &str,
4773− .subject(problem.subject)
2106+ line_num: usize,
4774− .suggest(problem.suggestion);
2107+ ctx: &mut ParseContext,
4775− let diagnostic = at_attribute(diagnostic, column, ctx);
2108+) -> Result<(Vec<Attribute>, String), ParseError> {
4776− ctx.diagnostics.push(diagnostic);
2109+ parse_attr_brackets_inner(input, line_num, ctx, false)
4779− if !check_element_prefixes(attr, &prefixes, base, line, column, ctx) {
4782− // The argument of `has(...)` or `nth-child(...)` goes into the CSS as
4784− for prefix in &prefixes {
4785− if let Some(reason) = css_breakout(prefix.trim_end_matches(':')) {
4789− "the prefix '{}' has {}: it can't be written into the page's CSS",
4797− // `nth-child():` or `has( ):`: CSS has no pseudo-class with an empty
4799− let empty_argument = |prefix: &str| {
4801− .strip_suffix("):")
4802− .and_then(|p| p.split_once('('))
4803− .is_some_and(|(_, argument)| argument.trim().is_empty())
4805− if let Some(empty) = prefixes.iter().find(|p| empty_argument(p)) {
4809− "'{}': `:{}()` takes an argument between its parentheses, as in CSS",
4811− vocab::pseudo_name(empty)
4817− // A pseudo-element is the last selector prefix: CSS has no
4818− // `::before:hover`
4819− let selectors: Vec<&str> = prefixes
4822− .filter(|p| vocab::at_rule_rank(p).is_none())
4824− // Only one: an element has one `::before`, which has no `::after`
4825− let elements: Vec<&str> = selectors
4828− .filter(|p| vocab::is_pseudo_element(p))
4830− if elements.len() > 1 {
4834− "'{}': `{}` and `{}` each select a pseudo-element, and a style applies to one \
4836− attr.key, elements[0], elements[1]
4842− if let Some(at) = selectors.iter().position(|p| vocab::is_pseudo_element(p))
4843− && at + 1 < selectors.len()
4845− let element = selectors[at];
4846− // The same prefixes, with the pseudo-element moved after the other
4847− // selector prefixes
4848− let mut order: Vec<&str> = prefixes.iter().copied().filter(|p| *p != element).collect();
4849− let last_selector = order
4851− .rposition(|p| vocab::at_rule_rank(p).is_none())
4852− .map_or(order.len(), |i| i + 1);
4853− order.insert(last_selector, element);
4854− let fixed = format!("{}{}", order.concat(), base);
4858− "'{}': `{}` selects a pseudo-element, which comes after the other selector \
4859− prefixes, as in CSS: write `{}`",
4860− attr.key, element, fixed
4866− // Under `children:` the styles go on the children, whose parent is this
4867− // element: a word that places an element in its parent can't say where
4868− if prefixes.contains(&"children:") && vocab::places_in_parent(base, attr.value.as_deref()) {
4869− // The CSS of `fill` and `shrink` depends on the direction: along
4870− // it, they are flex properties
4871− let (word, css) = match (base, attr.value.as_deref().map(str::trim)) {
4872− ("width", Some("fill")) => (
4874− " (`children:flex 1` in a row, `children:width 100%` otherwise)",
4876− ("height", Some("fill")) => (
4878− " (`children:flex 1` in a column, `children:height 100%` otherwise)",
4880− ("width", Some(_)) => (
4882− " (`children:flex-shrink 0` in a row, `children:width fit-content` otherwise)",
4884− ("height", Some(_)) => (
4886− " (`children:flex-shrink 0` in a column, `children:height fit-content` \
4894− "'{}{}': `{}` places an element in its parent, and under `children:` that \
4895− parent is this element: write `{}` on the children themselves, or the CSS \
4900− .map_or(String::new(), |v| format!(" {}", v.trim())),
4912−/// Check an attribute written as a style or a flag (not `key=value`): its
2112+fn parse_attr_brackets_inner(
4913−/// prefix, its name, and, for a style, its value. A name htmlang doesn't
2113+ input: &str,
4914−/// know but CSS could have (`corner-shape`) is passed to the CSS as written,
2114+ line_num: usize,
4915−/// with a warning; custom properties (`--brand`) and vendor-prefixed ones
4916−/// (`-webkit-...`) without one. Anything that can't be written into the
4917−/// page is an error; returns false then, and the attribute is left out.
4921− column: Option<usize>,
4922− before: Option<&Attribute>,
4923 ctx: &mut ParseContext,
2115 ctx: &mut ParseContext,
4924−) -> bool {
2116+ validate: bool,
4925− use crate::vocab;
2117+) -> Result<(Vec<Attribute>, String), ParseError> {
4926− let (prefixes, base) = vocab::split_prefixes(&attr.key);
2118+ let mut depth = 0;
4927− let fail = |ctx: &mut ParseContext, code: &'static str, message: String, subject: &str| {
2119+ let mut end_pos = 0;
4928− let diagnostic = Diagnostic::error(code, line, message).subject(subject);
4929− let diagnostic = at_attribute(diagnostic, column, ctx);
4930− ctx.diagnostics.push(diagnostic);
4934− if !check_prefixes(attr, line, column, ctx) {
2121+ for (i, c) in input.char_indices() {
4935− return false;
2122+ match c {
4936− }
2123+ '[' => depth += 1,
4937− let prefixed = !prefixes.is_empty();
2124+ ']' => {
4938− // `md:id=x`: `=` makes an HTML attribute, which has no states
2125+ depth -= 1;
4939− if prefixed && let Some((name, _)) = base.split_once('=') {
2126+ if depth == 0 {
4940− return fail(
2127+ end_pos = i;
4942− code::INVALID_PREFIX,
2129+ }
4944− "'{}': a prefix applies to a style, and `{}=` is an HTML attribute",
4950− let Some(value) = &attr.value else {
4951− // `inline` puts a file into the page as it compiles, which no
4952− // state or media condition can undo
4953− if base == "inline" && prefixed {
4956− code::INVALID_PREFIX,
4958− "'{}': `inline` puts the image's file into the page, which can't depend \
4965− if vocab::HTMLANG_FLAGS.contains(&base) {
4968− if vocab::is_html_flag(base) {
4972− return fail(
2131+ _ => {}
4974− code::INVALID_PREFIX,
4976− "'{}': a prefix applies to a style, and '{}' is an HTML attribute",
4982− if vocab::is_style_attribute(base)
4983− || vocab::is_custom_property(base)
4984− || vocab::is_vendor_property(base)
4988− code::MISSING_VALUE,
4989− format!("'{}' needs a value: `{} VALUE`", attr.key, attr.key),
4993− if vocab::is_html_attribute(base) && !prefixed {
4996− code::HTML_ATTRIBUTE_FORM,
4998− "'{}' is an HTML attribute that isn't a flag: write `{}=VALUE`",
5004− return unknown_attribute(attr, base, line, column, before, true, ctx);
5007− if vocab::HTMLANG_FLAGS.contains(&base) {
5010− code::INVALID_VALUE,
5012− "'{}' is a flag and takes no value: write `{}` alone",
5018− if vocab::is_style_attribute(base)
5019− || vocab::is_custom_property(base)
5020− || vocab::is_vendor_property(base)
5022− return check_css_value(attr, base, line, column, ctx);
5024− if vocab::is_html_attribute(base) && !prefixed {
5025− let diagnostic = Diagnostic::error(
5026− code::HTML_ATTRIBUTE_FORM,
5029− "'{}' is an HTML attribute: write `{}={}`",
5030− attr.key, attr.key, value
5033− .subject(attr.key.as_str());
5034− let diagnostic = at_attribute(diagnostic, column, ctx);
5035− ctx.diagnostics.push(diagnostic);
5038− let passes = vocab::is_property_name(base);
5039− unknown_attribute(attr, base, line, column, before, !passes, ctx)
5040− && check_css_value(attr, base, line, column, ctx)
5043−/// Whether an attribute of a bundle could pass a parameter to a function
5044−/// it is spliced into (`@let t [title Hello]`): a name without a prefix
5045−/// that isn't a style or a flag. Such a name is checked where the bundle is
5047−fn could_be_parameter(attr: &Attribute) -> bool {
5049− let key = attr.key.as_str();
5051− attr.value.is_none() && (vocab::HTMLANG_FLAGS.contains(&key) || vocab::is_html_flag(key));
5054− && !vocab::is_style_attribute(key)
5055− && key.starts_with(|c: char| c.is_alphabetic())
5058− .all(|c| c.is_alphanumeric() || matches!(c, '-' | '_'))
5061−/// At a call, a name close to one of the function's parameters is a
5062−/// misspelled parameter, not an attribute for its root: report it, and
5063−/// return true (it is left out).
5064−fn misspelled_parameter(
5066− text_keys: &[String],
5068− column: Option<usize>,
5069− ctx: &mut ParseContext,
5071− if text_keys.is_empty() || !could_be_parameter(attr) {
5074− let params: Vec<&str> = text_keys.iter().map(String::as_str).collect();
5075− let Some(closest) = suggest_closest(&attr.key, ¶ms) else {
5078− let what = if ctx.in_page {
5083− let diagnostic = Diagnostic::error(
5084− code::UNKNOWN_ATTRIBUTE,
5087− "unknown {} '{}', did you mean '{}'?",
5088− what, attr.key, closest
5091− .subject(attr.key.as_str())
5092− .suggest(Some(closest));
5093− let diagnostic = at_attribute(diagnostic, column, ctx);
5094− ctx.diagnostics.push(diagnostic);
5098−/// An attribute name htmlang doesn't know. A style whose name CSS could
2135+ if depth != 0 {
5099−/// have goes to the CSS as written, with a warning; anything else (a flag,
2136+ return Err(ParseError {
5100−/// a name that isn't a word) is an error. Returns whether it is kept.
2137+ line: line_num,
5101−fn unknown_attribute(
2138+ message: "unclosed '[' in attribute list".to_string(),
5102− attr: &Attribute,
2139+ });
5105− column: Option<usize>,
5106− before: Option<&Attribute>,
5108− ctx: &mut ParseContext,
5110− // `@td padding 8`: an element prefix without its colon
5111− if let Some(name) = base.strip_prefix('@')
5112− && crate::ast::ElementKind::from_name(name).is_some()
5114− let example = match attr.value.as_deref() {
5115− Some(value) => format!("{}:{}", attr.key, value.trim()),
5116− None => format!("{}:padding 8", attr.key),
5118− let diagnostic = Diagnostic::error(
5119− code::UNKNOWN_ATTRIBUTE,
5122− "unknown attribute '{}': an element prefix ends in a colon, as in `{}`",
5127− let diagnostic = at_attribute(diagnostic, column, ctx);
5128− ctx.diagnostics.push(diagnostic);
5131− // `[card]` where `card` is a bundle: it is used as `$card`
5132− if attr.value.is_none() && ctx.env.bundle(base).is_some() && base == attr.key {
5133− ctx.used_defines.insert(base.to_string());
5134− let diagnostic = Diagnostic::error(
5135− code::UNKNOWN_ATTRIBUTE,
5138− "unknown attribute '{}': '{}' is an attribute bundle, used as `${}`",
5143− .suggest(Some(format!("${}", base)));
5144− let diagnostic = at_attribute(diagnostic, column, ctx);
5145− ctx.diagnostics.push(diagnostic);
5148− // `hover:title x`: an HTML attribute's name is not a suggestion for
5151− suggest_closest(base, &crate::vocab::all_attributes()).filter(|&closest| closest != base);
5152− // `hx-trigger=load, every 2s`: right after a `key=value`, a name that
5153− // isn't close to one htmlang knows is the rest of that value, which
5154− // the comma ended. It is left out.
5155− let cut = before.filter(|b| b.html && b.value.is_some());
5156− let rest = match &attr.value {
5157− Some(value) => format!("{} {}", attr.key, value),
5158− None => attr.key.clone(),
5160− let joined = cut.map(|cut| {
5161− let value = cut.value.as_deref().unwrap_or("");
5163− format!("{}={}", cut.key, value),
5164− format!("{}={}\\, {}", cut.key, value, rest),
5167− if let (Some((cut, joined)), None) = (&joined, suggestion) {
5168− let diagnostic = Diagnostic::error(
5172− "unknown attribute '{}' after `{}`: if '{}' is the rest of its value, the comma \
5173− ended it. To keep a comma in a value, write `\\,`: `{}`",
5174− base, cut, rest, joined
5178− let diagnostic = at_attribute(diagnostic, column, ctx);
5179− ctx.diagnostics.push(diagnostic);
5182− let mut message = match (&suggestion, error) {
5183− (Some(closest), true) => {
5185− "unknown attribute '{}', did you mean '{}'?",
5189− (None, true) => format!("unknown attribute '{}'", attr.key),
5190− (Some(closest), false) => format!(
5191− "unknown CSS property '{}', did you mean '{}'? It is written to the CSS as it is",
5194− (None, false) => format!(
5195− "unknown CSS property '{}': it is written to the CSS as it is",
5199− // `box-shadow 0 1px red, 0 2px blue` or `font-family Inter,
5200− // sans-serif`: the comma ended the attribute, and the rest of the
5201− // value became one
5202− let rest_of_a_value = !base.starts_with(|c: char| c.is_ascii_alphabetic() || c == '-')
5203− || (suggestion.is_none() && attr.value.is_none() && before.is_some());
5204− if joined.is_some() || (rest_of_a_value && error) {
5205− if !message.ends_with('?') {
5209− Some((cut, joined)) => message.push_str(&format!(
5210− " If it is the rest of `{}`, the comma ended it: write `{}`",
5214− .push_str(" A comma separates attributes: to keep one in a value, write `\\,`"),
5217− let severity = if error {
5222− let diagnostic = Diagnostic::new(code::UNKNOWN_ATTRIBUTE, severity, line, message)
5224− .suggest(suggestion);
5225− let diagnostic = at_attribute(diagnostic, column, ctx);
5226− ctx.diagnostics.push(diagnostic);
5230−/// Evaluate the attributes of a list: bundles are spliced in, `if()`
2142+ let attrs_inner = &input[1..end_pos];
5231−/// chooses, and variables fill values. A variable fills only the value it
2143+ let remaining = input[end_pos + 1..].trim().to_string();
5232−/// is written in: attributes come from bundles, never from text. With
2144+ let attrs = parse_attr_list(attrs_inner, line_num, ctx, validate);
5233−/// `validate`, unknown names and invalid values are reported. `text_keys`
5234−/// are a called function's parameters: their values are text rather than
5235−/// CSS, and they aren't checked as attributes.
5237− tokens: &[syntax::Attr],
5239− ctx: &mut ParseContext,
5241− text_keys: &[String],
5242−) -> Vec<Attribute> {
5243− parse_attrs(tokens, line_num, ctx, validate, text_keys)
5245− .map(|(attr, _)| attr)
5249−/// [`parse_attr_list`], with the value of each attribute whose key is one
2146+ Ok((attrs, remaining))
5250−/// of `text_keys` (a call's parameters) as a value with its type (see
5251−/// [`ParseContext::slot_value`]), so a parameter can get a list or a
5254− tokens: &[syntax::Attr],
5256− ctx: &mut ParseContext,
5258− text_keys: &[String],
5259−) -> Vec<(Attribute, Option<Value>)> {
5260− let mut read = ReadAttrs::default();
5261− read_attrs(tokens, "", line_num, ctx, validate, text_keys, &mut read);
5265−/// The attributes of a list read so far, and the keys written (for the
2149+fn is_valid_hex_color(s: &str) -> bool {
5266−/// duplicate check).
2150+ if !s.starts_with('#') {
5267−#[derive(Default)]
2151+ return true; // Not a hex color, skip
5268−struct ReadAttrs {
2152+ }
5269− attrs: Vec<(Attribute, Option<Value>)>,
2153+ let hex = &s[1..];
5270− seen_keys: Vec<(String, bool)>,
2154+ matches!(hex.len(), 3 | 4 | 6 | 8) && hex.chars().all(|c| c.is_ascii_hexdigit())
5273−/// [`parse_attrs`] for the attributes of `tokens`, each under the prefixes
2157+fn parse_attr_list(
5274−/// `prefix` (`md:` for those of `md:[...]`), which distribute over a
2158+ input: &str,
5275−/// group, a bundle and the branch an `if()` takes. Only styles take a
5276−/// prefix, so an HTML attribute there is an error.
5278− tokens: &[syntax::Attr],
5280 line_num: usize,
2159 line_num: usize,
5281 ctx: &mut ParseContext,
2160 ctx: &mut ParseContext,
5282 validate: bool,
2161 validate: bool,
5283− text_keys: &[String],
2162+) -> Vec<Attribute> {
5284− out: &mut ReadAttrs,
2163+ let mut attrs = Vec::new();
5285−) {
2164+ let mut seen_keys: Vec<String> = Vec::new();
5286− let mut chosen = Vec::new();
2165+
5287− choose_attrs(
2166+ for part in split_commas(input) {
5288− tokens,
2167+ let part = part.trim();
5289− prefix,
2168+ // A whole attribute `if(cond, a, b)` is the chosen branch's text.
5290− line_num,
2169+ let chosen;
5291− ctx,
2170+ let part = match choose_if(part, ctx, line_num) {
5292− validate,
2171+ Some(branch) => {
5293− text_keys,
2172+ chosen = branch;
5294− &mut chosen,
2173+ chosen.as_str()
5297− for token in &chosen {
5298− let line = if token.span.line == 0 {
5303− let (key, value, html) = (token.key.clone(), token.value.clone(), token.html);
2177+ if part.is_empty() {
5304− let column = |at: usize| Some(token.span.column + at);
5306− // `md:[...]`, `md:$card`, `md:if(...)`: the prefixes apply to each
5307− // attribute there, and a prefix a parameter can't have
5308− if let Some(prefixed) = &token.prefixed {
5309− if let Some(inner) = group_prefix(token, prefixed, prefix, line, ctx) {
5311− prefixed.target.attrs(),
5320 continue;
2178 continue;
5323− // `$name` (or `${name}`) alone: an attribute bundle, spliced in
2181+ // $define reference — expand attribute bundle
5324− let bundle = key.strip_prefix('$').filter(|_| value.is_none() && !html);
2182+ if let Some(name) = part.strip_prefix('$')
5325− let bundle = bundle.and_then(|after| match interp::reference(after, &ctx.env)? {
2183+ && let Some(define_attrs) = ctx.defines.get(name)
5326− (interp::Reference::Var(name), len) if len == after.len() => Some(name),
2184+ {
5327− _ => None,
2185+ ctx.used_defines.insert(name.to_string());
5328− });
2186+ attrs.extend(define_attrs.clone());
5329− if let Some(name) = bundle {
5330− if let Some(define_attrs) = ctx.env.bundle(&name).cloned() {
5331− ctx.used_defines.insert(name.clone());
5332− for attr in define_attrs.iter() {
5333− if !prefix.is_empty() {
5334− let prefixed = Attribute {
5335− key: format!("{}{}", prefix, attr.key),
5338− if prefixed_parameter(&prefixed, text_keys, line, column(0), validate, ctx)
5342− if let Some(attr) =
5343− prefixed_member(attr, prefix, &name, line, column(0), validate, ctx)
5345− out.attrs.push((attr, None));
5349− let attrs = &out.attrs;
5350− // Checked here, where it is either a parameter or not
5351− let checked_here = validate
5353− && could_be_parameter(attr)
5354− && !text_keys.contains(&attr.key);
5356− && (misspelled_parameter(attr, text_keys, line, column(0), ctx)
5357− || !check_attribute(
5361− attrs.last().map(|(a, _)| a),
5367− out.attrs.push((attr.clone(), None));
5370− not_a_bundle(&name, line, column(0), ctx);
5374− // A name never comes from a variable
5375− if key.contains('$') {
5376− track_var_refs(&key, &mut ctx.used_variables);
5377− ctx.diagnostics.push(
5379− code::ATTRIBUTE_FROM_VARIABLE,
5382− "'{}': an attribute's name can't come from a variable. A variable \
5383− fills a value (`padding $size`), and whole attributes come from a \
5384− bundle (`@let name [padding 8]`, used as `[$name]`)",
5388− .subject(key.as_str()),
5390 continue;
2187 continue;
5393− // Only a style has states: `md:[id=x]`, `md:id=x`
2190+ track_var_refs(part, &mut ctx.used_variables);
5394− if html && (!prefix.is_empty() || !crate::vocab::split_prefixes(&key).0.is_empty()) {
2191+
5395− let written = format!("{}{}", prefix, key);
2192+ if let Some((attr, condition)) = split_trailing_if(part) {
5396− let (name, _) = crate::vocab::split_prefixes(&written);
2193+ ctx.diagnostics.push(Diagnostic {
5397− let diagnostic = Diagnostic::error(
2194+ line: line_num,
5398− code::INVALID_PREFIX,
2195+ column: None,
5399− line,
2196+ message: format!(
5400− format!(
2197+ "`KEY if CONDITION` was removed: write `if({}, {})`",
5401− "'{}=': a prefix applies to a style, and `{}=` is an HTML attribute, \
2198+ condition, attr
5402− which has no states",
5404− &written[name.concat().len()..]
5406− )
2200+ severity: Severity::Error,
5407− .subject(token.key.as_str());
2201+ source_line: None,
5408− let diagnostic = at_attribute(diagnostic, column(0), ctx);
2202+ });
5409− ctx.diagnostics.push(diagnostic);
5410 continue;
2203 continue;
5412− let key = if prefix.is_empty() {
2205+ // A value `if(cond, a, b)` picks `a` or `b` (free text) by `cond`;
5413− key
2206+ // an empty choice leaves the attribute out.
5414− } else {
2207+ let Some(part) = choose_if_value(part, ctx, line_num) else {
5415− format!("{}{}", prefix, key)
2208+ continue;
2210+ let part = substitute_vars(&part, &ctx.variables);
5418− // A value's variables are filled in. A style's value is CSS, where
2212+ let attr = if let Some((key, value)) = split_html_attribute(&part) {
5419− // quoted text keeps its quotes; an HTML attribute's (and a
2213+ Attribute {
5420− // parameter's) is text, where it loses them.
2214+ key: key.to_string(),
5421− let sink = if html || text_keys.contains(&key) {
2215+ value: Some(value.to_string()),
5422− Sink::Text
2216+ html: true,
5426− let mut filled = true;
5427− let mut quoted = None;
5428− let mut typed = None;
5429− let value = match value {
5431− // A parameter's value keeps its type
5432− Some(value) if !html && text_keys.contains(&key) => {
5433− let at = column(token.raw.len() - value.len());
5434− let (value, ok) = ctx.slot_value(&value, line, at);
5436− if let Value::Quoted(q) = &value {
5437− quoted = Some(q.clone());
5439− let text = value.to_string();
5440− typed = Some(value);
5443− Some(value) => {
2218+ } else if let Some((key, value)) = part.split_once(' ') {
5444− let at = column(token.raw.len() - value.len());
2219+ let value = value.trim().to_string();
5445− let (text, is_quoted, ok) = ctx.fill_value(&value, line, at, sink);
2220+ Attribute {
5446− filled = ok;
2221+ key: key.trim().to_string(),
5447− quoted = is_quoted;
2222+ value: Some(value),
5448− Some(text)
2223+ html: false,
2227+ key: part.to_string(),
5451− let attr = Attribute {
5457− // A value that couldn't be filled in is already reported, and a
5458− // parameter's value is text for the function
5459− let validate = validate && filled && !text_keys.contains(&attr.key);
5461− // A duplicate is reported (compare the full key, so `border` and
2233+ // Warn on duplicate attributes (compare full key so pseudo-class
5462− // `hover:border` differ, and the form, so `width=800` and
2234+ // variants like `border` and `hover:border` are not conflated)
5463− // `width 200` do too), and the later one wins
5464 if validate {
2235 if validate {
5465− let seen = (normal_key(&attr.key), attr.html);
2236+ if seen_keys.contains(&attr.key) {
5466− if out.seen_keys.contains(&seen) {
2237+ ctx.diagnostics.push(Diagnostic {
5467− let written = if attr.html { "=" } else { "" };
2238+ line: line_num,
5468− let message = format!(
2239+ column: None,
5469− "duplicate attribute '{}{}': the later one wins",
2240+ message: format!("duplicate attribute '{}'", attr.key),
5470− attr.key, written
2241+ severity: Severity::Warning,
5471− );
2242+ source_line: None,
5472− let diagnostic = Diagnostic::warning(code::DUPLICATE_ATTRIBUTE, line, message)
2243+ });
5473− .subject(attr.key.as_str());
5474− let diagnostic = at_attribute(diagnostic, column(0), ctx);
5475− ctx.diagnostics.push(diagnostic);
5476 } else {
2244 } else {
5477− out.seen_keys.push(seen);
2245+ seen_keys.push(attr.key.clone());
5481− if validate && misspelled_parameter(&attr, text_keys, line, column(0), ctx) {
2248+ // Color validation for hex colors
5482− continue;
2249+ if !attr.html
5483− }
2250+ && matches!(crate::vocab::base_attribute(&attr.key), "background" | "color")
5484− if prefixed_parameter(&attr, text_keys, line, column(0), validate, ctx) {
2251+ && let Some(ref val) = attr.value
5485− continue;
2252+ && val.starts_with('#')
5486− }
2253+ && !is_valid_hex_color(val)
5487− if validate && attr.html && attr.key == "class" {
2254+ {
5488− reserved_class(&attr, line, column(0), ctx);
2255+ ctx.diagnostics.push(Diagnostic {
5489− }
2256+ line: line_num,
5490− // `padding=4`: a style written as an HTML attribute, which the
2257+ column: None,
5491− // browser ignores (`width=` and `height=` are real on some
2258+ message: format!("invalid hex color '{}'", val),
5492− // elements, see `validate_tree`)
2259+ severity: Severity::Warning,
5493− if validate
2260+ source_line: None,
5494− && attr.html
2261+ });
5495− && crate::vocab::is_style_attribute(&attr.key)
2262+ }
5496− && !crate::vocab::HTML_ATTRIBUTES.contains(&attr.key.as_str())
5498− let value = token.value.as_deref().unwrap_or("").trim();
5499− let diagnostic = Diagnostic::warning(
5500− code::HTML_ATTRIBUTE_FORM,
5503− "'{0}={1}' is an HTML attribute, but {0} is a style: write `{0} {1}`",
5507− .subject(token.raw.as_str())
5508− .suggest(Some(format!("{} {}", attr.key, value)));
5509− let diagnostic = at_attribute(diagnostic, column(0), ctx);
5510− ctx.diagnostics.push(diagnostic);
5513− // A style or a flag: its name is checked, and what can't be
2265+ // Warn on unknown attributes. `key=value` HTML attributes may use any
5514− // written into the page is an error and left out
2266+ // name; everything else must be a known style.
5515− let checked = validate && !attr.html && !(ctx.in_bundle && could_be_parameter(&attr));
2267+ if validate && !attr.html {
5516− let before = out.attrs.last().map(|(a, _)| a);
2268+ let base_key = crate::vocab::base_attribute(attr.key.as_str());
5517− if checked && !check_attribute(&attr, line, column(0), before, ctx) {
2269+ let is_boolean_html =
5518− continue;
2270+ attr.value.is_none() && crate::vocab::BOOLEAN_HTML_ATTRS.contains(&base_key);
2271+ // A removed attribute that shares its name with a CSS property
2272+ // (bare `grid`) still gets its hint.
2273+ let removed = removed_attribute_hint(base_key)
2274+ .filter(|_| attr.value.is_none() || !crate::vocab::is_css_property(base_key));
2275+ if let Some(hint) = removed {
2276+ ctx.diagnostics.push(Diagnostic {
2280+ "attribute '{}' was removed: {} (run `htmlang upgrade`)",
2283+ severity: Severity::Warning,
2286+ } else if is_boolean_html || crate::vocab::is_style_attribute(base_key) {
2287+ validate_attr_value(&attr, line_num, ctx);
2288+ } else if crate::vocab::HTML_ATTRIBUTES.contains(&base_key)
2289+ || base_key.starts_with("aria-")
2290+ || base_key.starts_with("data-")
2292+ ctx.diagnostics.push(Diagnostic {
2296+ "'{}' is an HTML attribute: write `{}={}` (run `htmlang upgrade`)",
2299+ attr.value.as_deref().unwrap_or("")
2301+ severity: Severity::Warning,
2305+ let suggestion = suggest_closest(base_key, &crate::vocab::all_attributes());
2306+ let msg = match suggestion {
2309+ "unknown attribute '{}', did you mean '{}'?",
2313+ None => format!("unknown attribute '{}'", attr.key),
2315+ ctx.diagnostics.push(Diagnostic {
2319+ severity: Severity::Warning,
5521− out.attrs.push((attr, typed));
2325+ attrs.push(attr);
5525−/// At a call, a parameter under prefixes (`md:title x`, `md:[title x]`):
2331+/// Split an HTML attribute written `key=value` (`alt=`, `type=email`,
5526−/// a parameter has one value, with no states, so it is reported (with
2332+/// `aria-label=Close menu`). Returns `None` for style attributes.
5527−/// `validate`) and left out; returns true then. A parameter named like a
2333+fn split_html_attribute(part: &str) -> Option<(&str, &str)> {
5528−/// style (`color`) is a style under a prefix, for the root element.
2334+ let first_token = part.split(char::is_whitespace).next()?;
5529−fn prefixed_parameter(
2335+ let eq = first_token.find('=')?;
5530− attr: &Attribute,
2336+ let key = &part[..eq];
5531− text_keys: &[String],
2337+ let valid_key = key.starts_with(|c: char| c.is_ascii_alphabetic())
5532− line: usize,
2338+ && key
5533− column: Option<usize>,
2339+ .chars()
5534− validate: bool,
2340+ .all(|c| c.is_ascii_alphanumeric() || matches!(c, '-' | '_' | '.'));
5535− ctx: &mut ParseContext,
2341+ valid_key.then(|| (key, part[eq + 1..].trim()))
5537− let (prefixes, name) = crate::vocab::split_prefixes(&attr.key);
5539− || prefixes.is_empty()
5540− || !text_keys.iter().any(|k| k == name)
5541− || crate::vocab::is_style_attribute(name)
5546− let what = if ctx.in_page {
5551− let diagnostic = Diagnostic::error(
5552− code::INVALID_PREFIX,
5555− "'{}': `{}` is {}, which has one value, and a prefix applies to a style, \
5557− attr.key, name, what
5560− .subject(attr.key.as_str());
5561− let diagnostic = at_attribute(diagnostic, column, ctx);
5562− ctx.diagnostics.push(diagnostic);
5567−/// The prefixes of a prefixed group, bundle or `if()` inside `outer` (the
2344+fn split_commas(input: &str) -> Vec<&str> {
5568−/// prefixes of the groups it is in), when they are all known; else the
2345+ let mut parts = Vec::new();
5569−/// unknown one is reported. Text after a group's `]` is an error too.
2346+ let mut start = 0;
5570−fn group_prefix(
2347+ let mut depth = 0;
5571− token: &syntax::Attr,
2348+ let mut in_quotes = false;
5572− prefixed: &syntax::Prefixed,
2349+
5573− outer: &str,
2350+ for (i, c) in input.char_indices() {
5574− line: usize,
2351+ match c {
5575− ctx: &mut ParseContext,
2352+ '"' => in_quotes = !in_quotes,
5576−) -> Option<String> {
2353+ _ if in_quotes => {}
5577− let at = |ctx: &ParseContext, diagnostic: Diagnostic, span: syntax::Span| match &ctx
2354+ '[' | '(' => depth += 1,
5578− .current_source
2355+ ']' | ')' => depth -= 1,
5579− {
2356+ ',' if depth == 0 => {
5580− (current, Some(text)) if span.line != 0 && *current == span.line => {
2357+ parts.push(&input[start..i]);
5581− diagnostic.column(span.column).source(text.clone())
2358+ start = i + 1;
5585− if let syntax::Branch::Group {
5586− trailing: Some(trailing),
5588− } = &prefixed.target
5590− let diagnostic = Diagnostic::error(
5591− code::UNEXPECTED_ARGUMENT,
5594− "'{}' after the `]` of `{}[...]`: the prefixes apply to the attributes in the \
5595− group, so it goes inside it",
5596− trailing.raw, prefixed.prefix
5599− .subject(trailing.raw.as_str());
5600− let diagnostic = at(ctx, diagnostic, trailing.span);
5601− ctx.push_once(diagnostic);
5603− let (known, rest) = crate::vocab::split_prefixes(&prefixed.prefix);
5604− if !rest.is_empty() {
5605− let problem = unknown_prefix(rest).unwrap_or_else(|| {
5606− let written = rest.split_inclusive(':').next().unwrap_or(rest);
5608− message: format!("unknown prefix '{}'", written),
5609− subject: written.to_string(),
5613− let diagnostic = Diagnostic::error(code::UNKNOWN_PREFIX, line, problem.message)
2361+ }
5614− .subject(problem.subject)
5615− .suggest(problem.suggestion);
5616− let diagnostic = at(ctx, diagnostic, token.span);
5617− ctx.push_once(diagnostic);
5620− Some(format!("{}{}", outer, known.concat()))
2363+ parts.push(&input[start..]);
5623−/// An attribute of the bundle `bundle`, spliced in under `prefix`
2367+// ---------------------------------------------------------------------------
5624−/// (`md:$card`): the same attribute with the prefixes in front, when it can
2368+// Chain splitting (the > operator)
5625−/// take them. An HTML attribute can't; a style's prefixes are checked, as
2369+// ---------------------------------------------------------------------------
5626−/// is a flag or a name that isn't a style (a bundle's parameter), which
2370+
5627−/// under a prefix are attributes like any other.
2371+fn split_chain(content: &str) -> Vec<String> {
5628−fn prefixed_member(
2372+ let mut segments = Vec::new();
5629− attr: &Attribute,
2373+ let mut current = String::new();
5630− prefix: &str,
2374+ let chars: Vec<char> = content.chars().collect();
5631− bundle: &str,
2375+ let mut i = 0;
5632− line: usize,
2376+ let mut bracket_depth = 0;
5633− column: Option<usize>,
2377+
5634− validate: bool,
2378+ while i < chars.len() {
5635− ctx: &mut ParseContext,
2379+ if chars[i] == '[' {
5636−) -> Option<Attribute> {
2380+ bracket_depth += 1;
5637− let key = format!("{}{}", prefix, attr.key);
5640− let diagnostic = Diagnostic::error(
5641− code::INVALID_PREFIX,
5644− "'{}${}': the bundle has `{}=`, an HTML attribute, and a prefix applies to \
5645− styles, which have states",
5646− prefix, bundle, attr.key
5649− .subject(format!("{}${}", prefix, bundle));
5650− let diagnostic = at_attribute(diagnostic, column, ctx);
5651− ctx.diagnostics.push(diagnostic);
5653− return None;
2382+ if chars[i] == ']' {
5654− }
2383+ bracket_depth -= 1;
5655− let prefixed = Attribute {
5660− let fine = if attr.value.is_none() || could_be_parameter(attr) {
5661− check_attribute(&prefixed, line, column, None, ctx)
5663− check_prefixes(&prefixed, line, column, ctx)
5672−/// `class=hl-x`: the `hl-` prefix is htmlang's, for its generated classes,
2386+ // Match " > @" outside brackets
5673−/// whose rules would then apply to the element too. It goes into the page
2387+ if bracket_depth == 0
5674−/// as written, so this is a warning.
2388+ && i + 3 < chars.len()
5675−fn reserved_class(attr: &Attribute, line: usize, column: Option<usize>, ctx: &mut ParseContext) {
2389+ && chars[i] == ' '
5676− let classes = attr.value.as_deref().unwrap_or_default();
2390+ && chars[i + 1] == '>'
5677− for class in classes.split_whitespace() {
2391+ && chars[i + 2] == ' '
5678− if class.starts_with(crate::codegen::CLASS_PREFIX) {
2392+ && chars[i + 3] == '@'
5679− let diagnostic = Diagnostic::warning(
2393+ {
5680− code::INVALID_VALUE,
2394+ segments.push(current.trim().to_string());
5681− line,
2395+ current = String::new();
5682− format!(
2396+ i += 3; // skip " > ", keep the "@"
5683− "class '{}' starts with `{}`, which htmlang keeps for the classes it \
2397+ continue;
5684− generates, so their styles could apply to this element: give it \
5687− crate::codegen::CLASS_PREFIX
5691− let diagnostic = at_attribute(diagnostic, column, ctx);
5692− ctx.diagnostics.push(diagnostic);
2400+ current.push(chars[i]);
5697−/// A style's key as the CSS reads it, for finding duplicates: its at-rule
2404+ if !current.trim().is_empty() {
5698−/// prefixes in one order (`dark:md:` is `md:dark:`), then its selector
2405+ segments.push(current.trim().to_string());
5699−/// prefixes as written, whose order is the selector's.
5700−fn normal_key(key: &str) -> String {
5701− let (prefixes, name) = crate::vocab::split_prefixes(key);
5702− let mut at: Vec<(usize, &str)> = prefixes
5704− .filter_map(|p| crate::vocab::at_rule_rank(p).map(|rank| (rank, *p)))
5706− at.sort_unstable();
5708− let mut normal: String = at.iter().map(|(_, p)| *p).collect();
5709− for prefix in prefixes
5711− .filter(|p| crate::vocab::at_rule_rank(p).is_none())
5713− normal.push_str(prefix);
5715− normal.push_str(name);
5719−/// `[$name]` where `$name` isn't an attribute bundle.
2408+ segments
5720−fn not_a_bundle(name: &str, line: usize, column: Option<usize>, ctx: &mut ParseContext) {
5721− track_var_refs(&format!("${}", name), &mut ctx.used_variables);
5722− let is_value = interp::name_len(name) > 0 && interp::resolve(name, &ctx.env).is_some();
5723− let diagnostic = if is_value {
5725− code::ATTRIBUTE_FROM_VARIABLE,
5728− "'${}' is a value, not an attribute: attributes come from a bundle \
5729− (`@let name [padding 8]`, used as `[$name]`), and a value fills an \
5730− attribute's value (`padding ${}`)",
5735− } else if ctx.env.function(name).is_some() {
5736− ctx.used_functions.insert(name.to_string());
5738− code::UNDEFINED_VARIABLE,
5741− "'${}' is a function, not an attribute bundle: it is called as an element, \
5748− let mut bundles = ctx.env.bundle_names();
5749− bundles.sort_unstable();
5750− let suggestion = suggest_closest(name, &bundles);
5751− let message = match suggestion {
5752− Some(closest) => format!(
5753− "undefined attribute bundle '${}', did you mean '${}'?",
5756− None => format!("undefined attribute bundle '${}'", name),
5758− Diagnostic::error(code::UNDEFINED_VARIABLE, line, message)
5760− .suggest(suggestion)
5762− let diagnostic = match (&ctx.current_source, column) {
5763− ((current, Some(text)), Some(column)) if *current == line => {
5764− diagnostic.column(column).source(text.clone())
5768− ctx.diagnostics.push(diagnostic);
5771// ---------------------------------------------------------------------------
2411// ---------------------------------------------------------------------------
5772// Text segment parsing (inline {...} elements)
2412// Text segment parsing (inline {...} elements)
5773// ---------------------------------------------------------------------------
2413// ---------------------------------------------------------------------------
5775−/// While a slot is filled in, each escape (see [`syntax::ESCAPES`]) is a
2415+fn parse_text_segments(input: &str, ctx: &mut ParseContext) -> Vec<TextSegment> {
5776−/// private-use placeholder, U+E000 plus its place in the table, so it
2416+ let mut segments = Vec::new();
5777−/// can't start a variable, a quote or an inline element. Afterwards it
2417+ let mut current_text = String::new();
5778−/// becomes what it stands for.
2418+ let chars: Vec<char> = input.chars().collect();
5779−fn protect_escapes(text: &str) -> String {
5780− if !text.contains('\\') {
5781− return text.to_string();
5783− let mut out = String::with_capacity(text.len());
5784 let mut i = 0;
2419 let mut i = 0;
5785− while let Some(c) = text[i..].chars().next() {
5786− let len = syntax::escape_len(&text[i..]);
5792− let escape = &text[i..i + len];
5793− let index = syntax::ESCAPES.iter().position(|e| *e == escape);
5794− out.extend(index.and_then(|n| char::from_u32(0xE000 + n as u32)));
5800−/// The escape a placeholder stands for, as written (`\,`).
5801−fn escape_of(c: char) -> Option<&'static str> {
5802− let index = (c as u32).checked_sub(0xE000)?;
5803− syntax::ESCAPES.get(index as usize).copied()
5806−fn restore_escapes(text: &str) -> String {
5808− .fold(String::with_capacity(text.len()), |mut out, c| {
5809− match escape_of(c) {
5810− // What the escape stands for: what follows the backslash
5811− Some(escape) => out.push_str(&escape[1..]),
5812− None => out.push(c),
5818−/// Inside the quoted strings of a CSS value, `\"` and `\\` mean in CSS what
2421+ while i < chars.len() {
5819−/// they mean in htmlang, so they stay as written there.
2422+ if chars[i] == '{' && i + 1 < chars.len() && chars[i + 1] == '@' {
5820−fn keep_css_string_escapes(protected: &str) -> String {
2423+ // Flush accumulated plain text
5821− let mut out = String::with_capacity(protected.len());
2424+ if !current_text.is_empty() {
5822− let mut inside = false;
2425+ segments.push(TextSegment::Plain(substitute_vars(
5823− for c in protected.chars() {
2426+ ¤t_text,
5824− match escape_of(c) {
2427+ &ctx.variables,
5825− Some(escape @ ("\\\"" | "\\\\")) if inside => out.push_str(escape),
2428+ )));
5826− _ => {
2429+ current_text.clear();
5827− if c == '"' {
2430+ }
5828− inside = !inside;
2431+
2434+ let start = i + 1; // after {
2437+ if i >= chars.len() {
5830− out.push(c);
2440+ if chars[i] == '{' {
2442+ } else if chars[i] == '}' {
5837−/// Evaluate text: fill in the variables of its plain runs and build its
2451+ let inner: String = chars[start..i].iter().collect();
5838−/// inline elements. Each run is one slot, so a value can't make markup.
2452+ i += 1; // skip }
5839−fn text_segments(text: &syntax::Text, ctx: &mut ParseContext) -> Vec<TextSegment> {
2453+
5840− let mut segments = Vec::new();
2454+ match parse_single_element(&inner, ctx.current_line, ctx) {
5841− // The plain text so far, and where it starts
2455+ Ok(elem) => segments.push(TextSegment::Inline(elem)),
5842− let mut plain = String::new();
2456+ Err(e) => {
5843− let mut start: Option<syntax::Span> = None;
2457+ // Keep the braces as literal text, but flag what looks
5844− let flush = |plain: &mut String,
2458+ // like a mistyped inline element.
5845− start: &mut Option<syntax::Span>,
2459+ if inner.trim_start().starts_with('@') {
5846− segments: &mut Vec<TextSegment>,
2460+ ctx.diagnostics.push(Diagnostic {
5847− ctx: &mut ParseContext| {
2461+ line: ctx.current_line,
5848− if !plain.is_empty() {
2462+ column: None,
5849− let at = start.unwrap_or(text.span);
2463+ message: e.message,
5850− let filled = ctx.interpolate_text(plain, at.line, Some(at.column));
2464+ severity: Severity::Warning,
5851− segments.push(TextSegment::Plain(filled));
2465+ source_line: Some(input.to_string()),
5852− plain.clear();
2466+ });
5856− for segment in &text.segments {
5858− Segment::Plain { raw, span } => {
5859− start.get_or_insert(*span);
5860− plain.push_str(raw);
5862− Segment::Inline(inline) => {
5863− let line = ctx.current_line;
5864− match resolve(&inline.head, inline.text.as_ref(), line, &text.raw, ctx) {
5866− if !inline.closed {
5867− let d = Diagnostic::warning(
5868− code::UNCLOSED_BRACKET,
5871− "unclosed `{{`: the inline @{} runs to the end of the line. \
5872− An inline element ends with `}}` (a brace that is text is \
5877− let d = at_attribute(d, Some(inline.span.column), ctx);
5880− flush(&mut plain, &mut start, &mut segments, ctx);
5881− // A function called inline gets no children: its
5882− // content is the text after its attributes
5883− match Evaluator.complete(resolved, Vec::new(), ctx) {
5884− Ok(nodes) => segments.extend(inline_segments(nodes, line)),
5887− .get_or_insert_with(|| text.raw.as_str().into());
5888− ctx.diagnostics.push(e);
5893− // A misspelled element is an error inline too (a
5894− // brace that is text is written `\{`); the braces
5896− e.source_line = Some(text.raw.as_str().into());
5897− ctx.diagnostics.push(e);
5898− start.get_or_insert(inline.span);
5900− plain.push_str(&inline.raw);
2468+ current_text.push('{');
2469+ current_text.push_str(&inner);
2470+ current_text.push('}');
2474+ current_text.push(chars[i]);
5909− flush(&mut plain, &mut start, &mut segments, ctx);
5913−/// The variable `raw` is, when it is exactly one `$name` or `${name}`.
2479+ if !current_text.is_empty() {
5914−fn whole_reference(raw: &str, env: &Env) -> Option<String> {
2480+ segments.push(TextSegment::Plain(substitute_vars(
5915− let after = raw.trim().strip_prefix('$')?;
2481+ ¤t_text,
5916− match interp::reference(after, env)? {
2482+ &ctx.variables,
5917− (interp::Reference::Var(path), len) if len == after.len() => Some(path),
2483+ )));
5922−/// The attributes of `tokens` after each whole-attribute `if()` has
2489+// ---------------------------------------------------------------------------
5923−/// chosen (see [`syntax::Choice`]), in order, into `out`. The branch not
2490+// Variable substitution
5924−/// taken isn't evaluated; with `validate`, its attribute names are checked
2491+// ---------------------------------------------------------------------------
5925−/// like code that doesn't run, under the prefixes `prefix` the `if()` is
2492+
5926−/// under (`hover:if(...)`).
2493+// ---------------------------------------------------------------------------
5927−fn choose_attrs(
2494+// Condition evaluation for @if
5928− tokens: &[syntax::Attr],
2495+// ---------------------------------------------------------------------------
5930− line_num: usize,
2497+/// Inclusive integer range from `start` to `end` (counting down when
5931− ctx: &mut ParseContext,
2498+/// `start > end`), stepping by `step`. Stops instead of overflowing.
5932− validate: bool,
2499+/// The items of a text list: a range `A..B [step N]`, or comma-separated.
5933− text_keys: &[String],
2500+fn text_list_items(list: &str) -> Vec<String> {
5934− out: &mut Vec<syntax::Attr>,
2501+ if let Some((start, rest)) = list.split_once("..") {
5935−) {
2502+ let (end, step) = match rest.split_once(" step ") {
5936− for token in tokens {
2503+ Some((end, step)) => (end.trim(), step.trim().parse::<i64>().unwrap_or(1).max(1)),
5937− let Some(choice) = &token.choice else {
2504+ None => (rest.trim(), 1),
5938− out.push(token.clone());
5941− let Some(condition) = choice_shape(token, choice, line_num, ctx) else {
5944− let taken = match condition.span.line {
5945− 0 => ctx.condition(&condition.raw, line_num, None),
5946− line => ctx.condition(&condition.raw, line, Some(condition.span.column)),
5948− let (chosen, other) = match taken {
5949− true => (choice.branches.first(), choice.branches.get(1)),
5950− false => (choice.branches.get(1), choice.branches.first()),
5952− if let Some(other) = other {
2506+ if let (Ok(start), Ok(end)) = (start.trim().parse::<i64>(), end.parse::<i64>()) {
5953− track_var_refs(&branch_text(other), &mut ctx.used_variables);
2507+ return numeric_range(start, end, step);
5955− check_branch(token, other, prefix, line_num, ctx, text_keys);
5958− if let Some(branch) = chosen {
2511+ .map(|s| s.trim().to_string())
2512+ .filter(|s| !s.is_empty())
5972−/// Report what is wrong with the shape of `if()`: an empty condition, a
2516+/// Make `$target` (and `$target.key`, and nested lists) a copy of the list
5973−/// number of branches other than one or two, text after a group's `]`.
2517+/// item stored under `source`.
5974−/// Returns the condition when the `if()` can be evaluated.
2518+fn bind_item(vars: &mut HashMap<String, String>, source: &str, target: &str) {
5975−fn choice_shape<'a>(
2519+ let under = |key: &str, name: &str| {
5976− token: &syntax::Attr,
2520+ key.strip_prefix(name)
5977− choice: &'a syntax::Choice,
2521+ .is_some_and(|rest| rest.is_empty() || rest.starts_with(['.', '#']))
5979− ctx: &mut ParseContext,
5980−) -> Option<&'a syntax::Arg> {
5981− let line = if token.span.line == 0 {
5986− // The line the column points into, when it is the one being evaluated
2523+ vars.retain(|key, _| !under(key, target));
5987− let source = |ctx: &ParseContext, diagnostic: Diagnostic, at: usize| match &ctx.current_source {
2524+ let copies: Vec<(String, String)> = vars
5988− (current, Some(text)) if *current == at => diagnostic.source(text.clone()),
2525+ .iter()
5989− _ => diagnostic,
2526+ .filter(|(key, _)| under(key, source))
5990− };
2527+ .map(|(key, value)| (format!("{}{}", target, &key[source.len()..]), value.clone()))
5991− for branch in &choice.branches {
2528+ .collect();
5992− if let syntax::Branch::Group {
2529+ vars.extend(copies);
5993− trailing: Some(trailing),
2530+ // A record has no text of its own
5994− ..
2531+ vars.entry(target.to_string()).or_default();
5997− let diagnostic = source(
2534+fn numeric_range(start: i64, end: i64, step: i64) -> Vec<String> {
5998− ctx,
2535+ let mut items = Vec::new();
5999− Diagnostic::error(
2536+ let mut n = start;
6000− code::UNEXPECTED_ARGUMENT,
2537+ if start <= end {
6001− trailing.span.line,
2538+ while n <= end {
6002− format!(
2539+ items.push(n.to_string());
6003− "'{}' after the `]` of a group in if(): a branch is one attribute, \
2540+ match n.checked_add(step) {
6004− one `[group]` of attributes or one `$bundle`",
2541+ Some(next) => n = next,
6005− trailing.raw
2542+ None => break,
6008− .column(trailing.span.column)
6009− .subject(trailing.raw.as_str()),
6010− trailing.span.line,
6012− ctx.push_once(diagnostic);
6015− match &choice.condition {
2546+ while n >= end {
6016− Some(condition) if (1..=2).contains(&choice.branches.len()) => Some(condition),
2547+ items.push(n.to_string());
6017− _ => {
2548+ match n.checked_sub(step) {
6018− let diagnostic = source(
2549+ Some(next) => n = next,
6019− ctx,
2550+ None => break,
6020− Diagnostic::error(
2551+ }
6021− code::INVALID_EXPRESSION,
6024− "`{}`: if() takes a condition and one or two branches, \
6025− `if(CONDITION, A, B)`",
6029− .column(token.span.column),
6032− ctx.push_once(diagnostic);
6038−/// A branch's text, for the names it uses.
6039−fn branch_text(branch: &syntax::Branch) -> String {
6040− let raws: Vec<&str> = branch.attrs().iter().map(|a| a.raw.as_str()).collect();
6044−/// Check attributes that are never evaluated (in code that doesn't run,
2558+
6045−/// or the branch an `if()` didn't take), as far as they can be checked:
2559+/// Find a leftover `key if condition` (ignoring ` if ` inside parentheses
6046−/// names are, and literal values; a value with a variable depends on what
2560+/// or quotes), to point at `if()`.
6047−/// the variable holds. Each branch of an `if()` is checked on its own.
2561+fn split_trailing_if(part: &str) -> Option<(&str, &str)> {
6048−fn check_attrs(tokens: &[syntax::Attr], line: usize, ctx: &mut ParseContext, text_keys: &[String]) {
2562+ let mut depth = 0;
6049− parse_attr_list(&literal_attrs(tokens), line, ctx, true, text_keys);
2563+ let mut quote = None;
6050− check_choices(tokens, "", line, ctx, text_keys);
2564+ for (i, c) in part.char_indices() {
2566+ '"' | '\'' if quote == Some(c) => quote = None,
2567+ '"' | '\'' if quote.is_none() => quote = Some(c),
2568+ _ if quote.is_some() => {}
2571+ _ if depth == 0 && part[i..].starts_with(" if ") => {
2572+ return Some((&part[..i], part[i + 4..].trim()));
6053−/// [`check_attrs`] for a branch of the `if()` `token`, under the prefixes
2580+/// Evaluate `if(cond, a)` or `if(cond, a, b)` when it is all of `text`,
6054−/// `prefix` it is under: `hover:if($on, color red, [id=x])` checks
2581+/// returning the chosen branch (empty when `cond` fails and there is no `b`).
6055−/// `hover:[id=x]`, an error whichever branch is taken.
2582+fn choose_if(text: &str, ctx: &mut ParseContext, line: usize) -> Option<String> {
6056−fn check_branch(
2583+ let inner = text.strip_prefix("if(")?.strip_suffix(')')?;
6057− token: &syntax::Attr,
2584+ let args = split_if_args(inner);
6058− branch: &syntax::Branch,
2585+ // `if(a) (b)` isn't one call
6059− prefix: &str,
2586+ if split_trailing_paren(inner) || !(2..=3).contains(&args.len()) {
6060− line: usize,
2587+ return None;
6061− ctx: &mut ParseContext,
6062− text_keys: &[String],
6064− if prefix.is_empty() {
6065− check_attrs(branch.attrs(), line, ctx, text_keys);
6068− let list = syntax::AttrList {
2589+ let branch = if ctx.condition(args[0].trim(), line) {
6069− attrs: branch.attrs().to_vec(),
2590+ args[1]
6070− span: token.span,
2591+ } else {
6071− closed: true,
2592+ args.get(2).copied().unwrap_or("")
6072− quoted_close: None,
6074− let grouped = syntax::Attr {
6075− key: prefix.to_string(),
6078− raw: token.raw.clone(),
6081− prefixed: Some(Box::new(syntax::Prefixed {
6082− prefix: prefix.to_string(),
6083− prefix_span: token.span,
6084− target: syntax::Branch::Group {
6090− check_attrs(std::slice::from_ref(&grouped), line, ctx, text_keys);
2594+ Some(branch.trim().to_string())
6093−/// [`check_attrs`] for the branches of each `if()` of `tokens`, which are
2597+/// Whether the parentheses in `inner` close before its end, as in the
6094−/// under the prefixes `prefix`, also inside a prefixed group or as a
2598+/// inside of `if(a)(b)`.
6095−/// prefixed `if()`.
2599+fn split_trailing_paren(inner: &str) -> bool {
6096−fn check_choices(
2600+ let mut depth = 0i32;
6097− tokens: &[syntax::Attr],
2601+ let mut quote = None;
6098− prefix: &str,
2602+ for c in inner.chars() {
6099− line: usize,
2603+ match c {
6100− ctx: &mut ParseContext,
2604+ '"' | '\'' if quote == Some(c) => quote = None,
6101− text_keys: &[String],
2605+ '"' | '\'' if quote.is_none() => quote = Some(c),
6102−) {
2606+ _ if quote.is_some() => {}
6103− for token in tokens {
2607+ '(' => depth += 1,
6104− if let Some(choice) = &token.choice
2608+ ')' => {
6105− && choice_shape(token, choice, line, ctx).is_some()
2609+ depth -= 1;
6106− {
2610+ if depth < 0 {
6107− for branch in &choice.branches {
2611+ return true;
6108− check_branch(token, branch, prefix, line, ctx, text_keys);
2612+ }
6111− if let Some(prefixed) = &token.prefixed {
2616+ }
6112− let inner = format!("{}{}", prefix, prefixed.prefix);
2617+ false
6113− check_choices(prefixed.target.attrs(), &inner, line, ctx, text_keys);
2618+}
2620+/// Resolve a value written `if(cond, a, b)`: evaluate `cond` and keep the
2621+/// chosen branch's text, or `None` when the choice is empty. Other
2622+/// attributes are returned unchanged.
2623+fn choose_if_value(part: &str, ctx: &mut ParseContext, line: usize) -> Option<String> {
2624+ let Some(pos) = part.find(['=', ' ']) else {
2625+ return Some(part.to_string());
2627+ let (head, value) = part.split_at(pos + 1);
2628+ match choose_if(value.trim(), ctx, line) {
2629+ Some(branch) if branch.is_empty() => None,
2630+ Some(branch) => Some(format!("{}{}", head, branch)),
2631+ None => Some(part.to_string()),
2635+fn split_if_args(input: &str) -> Vec<&str> {
2636+ let mut parts = Vec::new();
2639+ let mut quote = None;
2640+ for (i, c) in input.char_indices() {
2642+ '"' | '\'' if quote == Some(c) => quote = None,
2643+ '"' | '\'' if quote.is_none() => quote = Some(c),
2644+ _ if quote.is_some() => {}
2647+ ',' if depth == 0 => {
2648+ parts.push(&input[start..i]);
2654+ parts.push(&input[start..]);
6118// ---------------------------------------------------------------------------
2658// ---------------------------------------------------------------------------
6119// Post-parse validation (context-dependent warnings)
2659// Post-parse validation (context-dependent warnings)
6120// ---------------------------------------------------------------------------
2660// ---------------------------------------------------------------------------
2662+/// Attributes that only make sense on container elements (@row, @el, @el).
2663+const CONTAINER_ONLY_ATTRS: &[&str] = &[
6122fn element_kind_name(kind: &ElementKind) -> String {
2674fn element_kind_name(kind: &ElementKind) -> String {
6123 format!("@{}", kind.name())
2675 format!("@{}", kind.name())
6126−/// HTML elements whose start tag ends an open `<p>`: written inside a
6127−/// `@paragraph`, the browser moves them out of it. (`div` isn't here:
6128−/// inside text, htmlang writes its `<div>`s as `<span>`s.)
6130−const ENDS_A_PARAGRAPH: &[&str] = &[
6131− "address", "article", "aside", "blockquote", "dd", "details", "dialog", "dl", "dt",
6132− "fieldset", "figcaption", "figure", "footer", "form", "h1", "h2", "h3", "h4", "h5", "h6",
6133− "header", "hgroup", "hr", "li", "main", "menu", "nav", "ol", "p", "pre", "search",
6134− "section", "summary", "table", "ul",
6137−/// The HTML element `kind` is written as, if the browser would take it out
2678+fn is_container(kind: &ElementKind) -> bool {
6138−/// of a `<p>`.
2679+ matches!(kind, ElementKind::Row | ElementKind::El)
6139−fn ends_a_paragraph(kind: &ElementKind) -> Option<&'static str> {
2680+ || kind.spec().is_some_and(|spec| spec.container)
6140− let html = match kind {
6141− ElementKind::Paragraph => "p",
6142− ElementKind::Tag(spec) => spec.html,
6145− ENDS_A_PARAGRAPH.contains(&html).then_some(html)
6148/// Stricter checks for `htmlang lint`, on top of the diagnostics every
2683/// Stricter checks for `htmlang lint`, on top of the diagnostics every
@@ -6152,171 +2687,133 @@ pub fn lint(nodes: &[Node]) -> Vec<Diagnostic> {
6152 fn walk(nodes: &[Node], depth: usize, out: &mut Vec<Diagnostic>) {
2687 fn walk(nodes: &[Node], depth: usize, out: &mut Vec<Diagnostic>) {
6153 for node in nodes {
2688 for node in nodes {
6154 let Node::Element(elem) = node else { continue };
2689 let Node::Element(elem) = node else { continue };
6155− let start = out.len();
2690+ let mut warn = |message: String| {
6156− let mut warn = |code: &'static str, message: String| {
2691+ out.push(Diagnostic {
6157− out.push(Diagnostic::warning(code, elem.line_num, message))
2692+ line: elem.line_num,
2695+ severity: Severity::Warning,
6159 if depth > 10 {
2699 if depth > 10 {
6160− warn(
2700+ warn(format!(
6161− code::DEEP_NESTING,
2701+ "deeply nested element ({} levels): consider simplifying",
6162− format!(
2702+ depth
6163− "deeply nested element ({} levels): consider simplifying",
2703+ ));
6168− // A function's body may draw with an empty element (a spacer,
2705+ if matches!(elem.kind, ElementKind::Row | ElementKind::El)
6169− // a dot): only one written in the page is flagged
6170− if elem.kind.layout().is_container()
6171 && elem.children.is_empty()
2706 && elem.children.is_empty()
6172− && elem.function.is_none()
6174− warn(
2708+ warn(format!("empty container (@{}) has no children", elem.kind.name()));
6175− code::EMPTY_CONTAINER,
6176− format!("empty container (@{}) has no children", elem.kind.name()),
6179 if elem.kind.is_tag("button") && !elem.attrs.iter().any(|a| a.key == "type") {
2710 if elem.kind.is_tag("button") && !elem.attrs.iter().any(|a| a.key == "type") {
6180− warn(
2711+ warn("@button missing 'type' attribute (defaults to submit)".to_string());
6181− code::MISSING_BUTTON_TYPE,
6182− "@button missing 'type' attribute (defaults to submit)".to_string(),
6185− in_function_body(elem, &mut out[start..]);
6186 walk(&elem.children, depth + 1, out);
2713 walk(&elem.children, depth + 1, out);
6189 let mut out = Vec::new();
2716 let mut out = Vec::new();
6190 walk(nodes, 0, &mut out);
2717 walk(nodes, 0, &mut out);
6195−/// `in_paragraph`: the nodes are inside a `@paragraph` (and not inside a
2721+
6196−/// `@button` in it, which the browser keeps whole).
6197fn validate_tree(
2722fn validate_tree(
6198 nodes: &[Node],
2723 nodes: &[Node],
6199 parent_kind: Option<&ElementKind>,
2724 parent_kind: Option<&ElementKind>,
6200− in_paragraph: bool,
6201 diagnostics: &mut Vec<Diagnostic>,
2725 diagnostics: &mut Vec<Diagnostic>,
6203 for node in nodes {
2727 for node in nodes {
6204− // An element inside a line of text (`{@kbd ...}`, an inline call)
6205− // is checked like one on a line of its own
6206− if let Node::Text(segments) = node {
6207− let inline: Vec<Node> = segments
6209− .filter_map(|segment| match segment {
6210− TextSegment::Inline(elem) => Some(Node::Element(elem.clone())),
6214− validate_tree(&inline, parent_kind, in_paragraph, diagnostics);
6216 if let Node::Element(elem) = node {
2728 if let Node::Element(elem) = node {
6217− let start = diagnostics.len();
6218− dropped_by_the_element(elem, diagnostics);
6219− if in_paragraph && let Some(html) = ends_a_paragraph(&elem.kind) {
6221− Diagnostic::warning(
6222− code::BLOCK_IN_PARAGRAPH,
6225− "{0} inside @paragraph: HTML ends a <p> before a <{1}>, so the \
6226− browser moves the <{1}> out of the paragraph. Put {0} after the \
6227− paragraph, or use @el, @row or @grid, which are laid out inline \
6229− element_kind_name(&elem.kind),
6233− .subject(elem.kind.name()),
6236 for attr in &elem.attrs {
2729 for attr in &elem.attrs {
6237 let base = crate::vocab::base_attribute(&attr.key);
2730 let base = crate::vocab::base_attribute(&attr.key);
6238−
2731+ if base == "width"
6239− // htmlang's words for laying out children, on an element
2732+ && attr.value.as_deref() == Some("fill")
6240− // that doesn't lay out its children: left out (codegen)
2733+ && !matches!(parent_kind, Some(ElementKind::Row))
6241− if !attr.html
2734+ {
6242− && crate::vocab::CONTAINER_ATTRIBUTES.contains(&base)
2735+ diagnostics.push(Diagnostic {
6243− && !elem.kind.layout().is_container()
2736+ line: elem.line_num,
6244− && !has_no_element(&elem.kind)
2737+ column: None,
6245− && !crate::vocab::split_prefixes(&attr.key)
2738+ message: "'width fill' works best inside @row; using 100% as fallback"
6246− .0
2739+ .to_string(),
6247− .contains(&"children:")
2740+ severity: Severity::Warning,
2744+ if base == "height"
2745+ && attr.value.as_deref() == Some("fill")
2746+ && !parent_kind.is_some_and(ElementKind::is_column)
6249− diagnostics.push(not_a_container(&elem.kind, elem.line_num, base));
2748+ diagnostics.push(Diagnostic {
2749+ line: elem.line_num,
2751+ message: "'height fill' works best inside @el; using 100% as fallback"
2753+ severity: Severity::Warning,
2758+ // Container-only attributes on non-container elements
2759+ if CONTAINER_ONLY_ATTRS.contains(&base) && !is_container(&elem.kind) {
2760+ diagnostics.push(Diagnostic {
2761+ line: elem.line_num,
2764+ "'{}' has no effect on {} (only works on @row, @el, @el)",
2766+ element_kind_name(&elem.kind)
2768+ severity: Severity::Warning,
6252 // Form-specific: placeholder only on @input/@textarea
2773 // Form-specific: placeholder only on @input/@textarea
6253 if base == "placeholder"
2774 if base == "placeholder"
6254 && !(elem.kind.is_tag("input") || elem.kind.is_tag("textarea"))
2775 && !(elem.kind.is_tag("input") || elem.kind.is_tag("textarea"))
6256− diagnostics.push(Diagnostic::new(
2777+ diagnostics.push(Diagnostic {
6257− code::NO_EFFECT,
2778+ line: elem.line_num,
6258− Severity::Warning,
2779+ column: None,
6259− elem.line_num,
2780+ message: format!(
6261 "'placeholder' has no effect on {} (only works on @input, @textarea)",
2781 "'placeholder' has no effect on {} (only works on @input, @textarea)",
6262 element_kind_name(&elem.kind)
2782 element_kind_name(&elem.kind)
6264− ));
2784+ severity: Severity::Warning,
6267− // 'for' only on @label and @output
2789+ // 'for' only on @label
6268− if base == "for" && !(elem.kind.is_tag("label") || elem.kind.is_tag("output")) {
2790+ if base == "for" && !elem.kind.is_tag("label") {
6269− diagnostics.push(Diagnostic::new(
2791+ diagnostics.push(Diagnostic {
6270− code::NO_EFFECT,
2792+ line: elem.line_num,
6271− Severity::Warning,
2793+ column: None,
6272− elem.line_num,
2794+ message: format!(
6273− format!(
2795+ "'for' has no effect on {} (only works on @label)",
6274− "'for' has no effect on {} (only works on @label and @output)",
6275 element_kind_name(&elem.kind)
2796 element_kind_name(&elem.kind)
6277− ));
2798+ severity: Severity::Warning,
6278− }
2799+ source_line: None,
6280− // `width=` and `height=` are HTML attributes of media and
6281− // embedded content only; elsewhere they are styles
6283− && (base == "width" || base == "height")
6284− && !matches!(elem.kind, ElementKind::Image)
6286− "video", "canvas", "iframe", "embed", "object", "input", "source",
6289− .any(|tag| elem.kind.is_tag(tag))
6291− let value = attr.value.as_deref().unwrap_or("");
6293− Diagnostic::warning(
6294− code::HTML_ATTRIBUTE_FORM,
6297− "'{0}={1}' has no effect on {2}, which has no {0} attribute: \
6298− the style is written `{0} {1}`",
6301− element_kind_name(&elem.kind)
6304− .subject(format!("{}={}", base, value)),
6308 // 'rows'/'cols' only on @textarea
2803 // 'rows'/'cols' only on @textarea
6309− if (base == "rows" || base == "cols") && !elem.kind.is_tag("textarea") {
2804+ if (base == "rows" || base == "cols") && !elem.kind.is_tag("textarea")
6310− diagnostics.push(Diagnostic::new(
2805+ {
6311− code::NO_EFFECT,
2806+ diagnostics.push(Diagnostic {
6312− Severity::Warning,
2807+ line: elem.line_num,
6313− elem.line_num,
2808+ column: None,
6314− format!(
2809+ message: format!(
6315 "'{}' has no effect on {} (only works on @textarea)",
2810 "'{}' has no effect on {} (only works on @textarea)",
6317 element_kind_name(&elem.kind)
2812 element_kind_name(&elem.kind)
6319− ));
2814+ severity: Severity::Warning,
6322 // Media-specific attributes only on @video/@audio
2819 // Media-specific attributes only on @video/@audio
@@ -6331,35 +2828,40 @@ fn validate_tree(
6331 | "preload"
2828 | "preload"
6332 ) && !matches!(elem.kind.name(), "video" | "audio")
2829 ) && !matches!(elem.kind.name(), "video" | "audio")
6334− diagnostics.push(Diagnostic::new(
2831+ diagnostics.push(Diagnostic {
6335− code::NO_EFFECT,
2832+ line: elem.line_num,
6336− Severity::Warning,
2833+ column: None,
6337− elem.line_num,
2834+ message: format!(
6339 "'{}' has no effect on {} (only works on @video, @audio)",
2835 "'{}' has no effect on {} (only works on @video, @audio)",
6341 element_kind_name(&elem.kind)
2837 element_kind_name(&elem.kind)
6343− ));
2839+ severity: Severity::Warning,
6346 // Missing alt text on @image
2844 // Missing alt text on @image
6347 if matches!(elem.kind, ElementKind::Image) && !elem.attrs.iter().any(|a| a.key == "alt")
2845 if matches!(elem.kind, ElementKind::Image) && !elem.attrs.iter().any(|a| a.key == "alt")
6349− diagnostics.push(Diagnostic::new(
2847+ diagnostics.push(Diagnostic {
6350− code::MISSING_ALT,
2848+ line: elem.line_num,
6351− Severity::Warning,
2849+ column: None,
6352− elem.line_num,
2850+ message: "@image missing 'alt' attribute (accessibility)".to_string(),
6353− "@image missing 'alt' attribute (accessibility)".to_string(),
2851+ severity: Severity::Warning,
6354− ));
2852+ source_line: None,
6356− if elem.kind.is_tag("input") && !elem.attrs.iter().any(|a| a.key == "type") {
2855+ if elem.kind.is_tag("input")
6357− diagnostics.push(Diagnostic::new(
2856+ && !elem.attrs.iter().any(|a| a.key == "type")
6358− code::MISSING_INPUT_TYPE,
2857+ {
6359− Severity::Warning,
2858+ diagnostics.push(Diagnostic {
6360− elem.line_num,
2859+ line: elem.line_num,
6361− "@input missing 'type' attribute (defaults to 'text')".to_string(),
2860+ column: None,
6362− ));
2861+ message: "@input missing 'type' attribute (defaults to 'text')".to_string(),
2862+ severity: Severity::Warning,
6364 if matches!(elem.kind, ElementKind::Link) {
2866 if matches!(elem.kind, ElementKind::Link) {
6365 // For @link, argument is the URL, not text content
2867 // For @link, argument is the URL, not text content
@@ -6370,50 +2872,44 @@ fn validate_tree(
6371 .any(|a| a.key == "aria-label" || a.key == "title")
2873 .any(|a| a.key == "aria-label" || a.key == "title")
6373− diagnostics.push(Diagnostic::new(
2875+ diagnostics.push(Diagnostic {
6374− code::MISSING_LINK_TEXT,
2876+ line: elem.line_num,
6375− Severity::Warning,
2877+ column: None,
6376− elem.line_num,
2878+ message: "@link has no visible text or aria-label (accessibility)"
6377− "@link has no visible text or aria-label (accessibility)".to_string(),
2879+ .to_string(),
6378− ));
2880+ severity: Severity::Warning,
6382− // Contrast ratio check for hex color pairs, each pair on the
2886+ // Contrast ratio check for hex color pairs
6383− // same elements: the element's own, or those an element prefix
2887+ {
6384− // (`@td:`) picks out inside it
2888+ let bg_color = elem
6385− let inside = |key: &str| {
2889+ .attrs
6386− crate::vocab::split_prefixes(key)
2890+ .iter()
6387− .0
2891+ .find(|a| crate::vocab::base_attribute(&a.key) == "background")
6388− .into_iter()
2892+ .and_then(|a| a.value.as_deref());
6389− .find_map(crate::vocab::element_prefix)
2893+ let fg_color = elem
6390− .map(str::to_string)
2894+ .attrs
6392− let mut targets: Vec<Option<String>> = Vec::new();
2896+ .find(|a| crate::vocab::base_attribute(&a.key) == "color")
6393− for attr in elem.attrs.iter().filter(|a| !a.html) {
2897+ .and_then(|a| a.value.as_deref());
6394− let target = inside(&attr.key);
6395− if !targets.contains(&target) {
6396− targets.push(target);
6399− for target in targets {
6400− let color = |property: &str| {
6403− .filter(|a| !a.html && inside(&a.key) == target)
6404− .find(|a| crate::vocab::base_attribute(&a.key) == property)
6405− .and_then(|a| a.value.as_deref())
6407− let (bg_color, fg_color) = (color("background"), color("color"));
6408 if let (Some(bg), Some(fg)) = (bg_color, fg_color)
2898 if let (Some(bg), Some(fg)) = (bg_color, fg_color)
6409− && let (Some(bg_rgb), Some(fg_rgb)) = (parse_hex_rgb(bg), parse_hex_rgb(fg))
2899+ && let (Some(bg_rgb), Some(fg_rgb)) = (crate::expr::parse_hex_rgb(bg), crate::expr::parse_hex_rgb(fg))
6411 let ratio = contrast_ratio(bg_rgb, fg_rgb);
2901 let ratio = contrast_ratio(bg_rgb, fg_rgb);
6412 if ratio < 4.5 {
2902 if ratio < 4.5 {
6413− diagnostics.push(Diagnostic::new(code::LOW_CONTRAST, Severity::Warning, elem.line_num, format!(
2903+ diagnostics.push(Diagnostic {
2904+ line: elem.line_num,
6414 "low contrast ratio {:.1}:1 between '{}' and '{}' (WCAG AA requires 4.5:1)",
2907 "low contrast ratio {:.1}:1 between '{}' and '{}' (WCAG AA requires 4.5:1)",
6415 ratio, fg, bg
2908 ratio, fg, bg
2910+ severity: Severity::Warning,
@@ -6428,34 +2924,45 @@ fn validate_tree(
6428 let has_title = elem.attrs.iter().any(|a| a.key == "title");
2924 let has_title = elem.attrs.iter().any(|a| a.key == "title");
6429 let in_label = parent_kind.is_some_and(|k| k.is_tag("label"));
2925 let in_label = parent_kind.is_some_and(|k| k.is_tag("label"));
6430 if !has_id && !has_aria_label && !has_title && !in_label {
2926 if !has_id && !has_aria_label && !has_title && !in_label {
6431− diagnostics.push(Diagnostic::new(code::MISSING_LABEL, Severity::Warning, elem.line_num, format!(
2927+ diagnostics.push(Diagnostic {
2928+ line: elem.line_num,
6432 "{} should have an 'id' (with matching @label[for]), 'aria-label', or be wrapped in @label (accessibility)",
2931 "{} should have an 'id' (with matching @label[for]), 'aria-label', or be wrapped in @label (accessibility)",
6433 element_kind_name(&elem.kind)
2932 element_kind_name(&elem.kind)
2934+ severity: Severity::Warning,
6438 // @iframe should have title attribute
2940 // @iframe should have title attribute
6439− if elem.kind.is_tag("iframe") && !elem.attrs.iter().any(|a| a.key == "title") {
2941+ if elem.kind.is_tag("iframe")
6440− diagnostics.push(Diagnostic::new(
2942+ && !elem.attrs.iter().any(|a| a.key == "title")
6441− code::MISSING_TITLE,
2943+ {
6442− Severity::Warning,
2944+ diagnostics.push(Diagnostic {
6443− elem.line_num,
2945+ line: elem.line_num,
6444− "@iframe missing 'title' attribute (accessibility)".to_string(),
2946+ column: None,
6445− ));
2947+ message: "@iframe missing 'title' attribute (accessibility)".to_string(),
2948+ severity: Severity::Warning,
6448 // @button should have accessible text
2953 // @button should have accessible text
6449 if elem.kind.is_tag("button") {
2954 if elem.kind.is_tag("button") {
6450− let has_text = !elem.children.is_empty();
2955+ let has_text = elem.argument.is_some() || !elem.children.is_empty();
6451 let has_aria = elem.attrs.iter().any(|a| a.key == "aria-label");
2956 let has_aria = elem.attrs.iter().any(|a| a.key == "aria-label");
6452 if !has_text && !has_aria {
2957 if !has_text && !has_aria {
6453− diagnostics.push(Diagnostic::new(
2958+ diagnostics.push(Diagnostic {
6454− code::MISSING_BUTTON_TEXT,
2959+ line: elem.line_num,
6455− Severity::Warning,
2960+ column: None,
6456− elem.line_num,
2961+ message: "@button has no text content or aria-label (accessibility)"
6457− "@button has no text content or aria-label (accessibility)".to_string(),
2962+ .to_string(),
6458− ));
2963+ severity: Severity::Warning,
@@ -6468,15 +2975,16 @@ fn validate_tree(
6468 let has_track = elem
2975 let has_track = elem
6469 .children
2976 .children
6471− .any(|c| matches!(c, Node::Element(e) if e.kind.is_tag("track")));
2978+ .any(|c| matches!(c, Node::Element(e) if e.kind.is_tag("source")));
6472 if !has_aria && !has_track {
2979 if !has_aria && !has_track {
6473− diagnostics.push(Diagnostic::new(
2980+ diagnostics.push(Diagnostic {
6474− code::MISSING_CAPTIONS,
2981+ line: elem.line_num,
6475− Severity::Warning,
2982+ column: None,
6476− elem.line_num,
2983+ message: "@video should have aria-label or captions for accessibility"
6477− "@video should have aria-label or a captions @track for accessibility"
6478 .to_string(),
2984 .to_string(),
6479− ));
2985+ severity: Severity::Warning,
@@ -6486,204 +2994,20 @@ fn validate_tree(
6486 && let Ok(n) = val.parse::<i32>()
2994 && let Ok(n) = val.parse::<i32>()
6487 && n > 0
2995 && n > 0
6489− diagnostics.push(Diagnostic::new(code::POSITIVE_TABINDEX, Severity::Warning, elem.line_num, format!("tabindex {} is positive — avoid positive tabindex values as they disrupt natural tab order", n)));
2997+ diagnostics.push(Diagnostic {
2998+ line: elem.line_num,
3000+ message: format!("tabindex {} is positive — avoid positive tabindex values as they disrupt natural tab order", n),
3001+ severity: Severity::Warning,
6491− in_function_body(elem, &mut diagnostics[start..]);
6493− // An element that ends the <p> takes what is inside it out of
6494− // the paragraph too, so only it is reported
6495− let in_paragraph = elem.kind == ElementKind::Paragraph
6497− && ends_a_paragraph(&elem.kind).is_none()
6498− && !elem.kind.is_tag("button"));
6499− validate_tree(&elem.children, Some(&elem.kind), in_paragraph, diagnostics);
6504−/// What an element has no place for in HTML, which would otherwise be
6505−/// left out of the page: attributes on `@fragment` (which has no element
6506−/// of its own), styles on `@script` (which isn't shown), a body under a
6507−/// `@script` that has a src (which the browser doesn't run), an element
6508−/// under a `@script` (whose body is code), and content in a void element
6509−/// such as `@input`.
6510−fn dropped_by_the_element(elem: &Element, diagnostics: &mut Vec<Diagnostic>) {
6511− let name = elem.kind.name();
6512− let keys = |attrs: Vec<&Attribute>| {
6515− .map(|a| format!("'{}'", a.key))
6516− .collect::<Vec<_>>()
6519− let mut error = |code: &'static str, message: String| {
6520− diagnostics.push(Diagnostic::error(code, elem.line_num, message).subject(name))
6522− if elem.kind == ElementKind::Fragment && !elem.attrs.is_empty() {
6524− code::UNEXPECTED_ARGUMENT,
6526− "@fragment has no element of its own to put attributes on, so {} would go \
6527− nowhere: put them on its children, or use @el",
6528− keys(elem.attrs.iter().collect())
6532− // The leading argument given twice: an attribute passed to the root
6533− // of a function whose body gives the argument (written on one line,
6534− // it is reported where it is read, and the attribute wins there)
6535− if let Some(argument) = &elem.argument
6536− && let Some(attr) = elem
6539− .find(|a| a.html && elem.kind.arg().attributes().contains(&a.key.as_str()))
6542− code::DUPLICATE_ATTRIBUTE,
6544− "@{} takes '{}' as its {}, and it also has {}={}: give it once",
6547− leading_name(&elem.kind),
6549− attr.value.as_deref().unwrap_or("")
6553− if elem.kind.is_verbatim() {
6554− let styles: Vec<&Attribute> = elem
6557− .filter(|a| !a.html && !crate::vocab::is_html_flag(&a.key))
6559− if !styles.is_empty() {
6561− code::UNEXPECTED_ARGUMENT,
6563− "@{} isn't shown on the page, so its styles {} would go nowhere",
6569− let src = elem.argument.clone().or_else(|| {
6572− .find(|a| a.html && a.key == "src")
6573− .map(|a| a.value.clone().unwrap_or_default())
6575− if let Some(src) = src
6576− && !elem.children.is_empty()
6579− code::UNEXPECTED_CONTENT,
6581− "@{0} has both a src ('{1}') and a body: the browser runs only the file, \
6582− so the body would go nowhere. Put the code in {1}, or leave out the src",
6586− } else if let Some(Node::Element(child)) = elem
6589− .find(|child| matches!(child, Node::Element(_)))
6591− // `@script > @b x`: its body is code, not elements
6593− code::UNEXPECTED_CONTENT,
6595− "@{} holds its code as the lines under it, kept as written, so @{} would \
6603− if elem.kind != ElementKind::Image && elem.attrs.iter().any(|a| !a.html && a.key == "inline") {
6605− code::UNEXPECTED_ARGUMENT,
6607− "`inline` puts an image's file into the page, and @{} has none: it only \
6613− if elem.kind.layout() == Layout::Void && !elem.children.is_empty() {
6615− code::UNEXPECTED_CONTENT,
6617− "@{} takes no content: it is an element without a closing tag, so its text \
6618− and indented lines would go nowhere",
6625−/// `@fragment`, `@script`, `@children` and `@slot`, whose attributes are
6626−/// reported on their own (see `dropped_by_the_element`).
6627−fn has_no_element(kind: &ElementKind) -> bool {
6630− ElementKind::Fragment | ElementKind::Children | ElementKind::Slot(_)
6631− ) || kind.is_verbatim()
6634−/// htmlang's word `word` for laying out children (`spacing`, `wrap`,
6635−/// `grid-cols`, `grid-rows`) on an element that doesn't lay out its
6636−/// children: an error, and the word is left out.
6637−fn not_a_container(kind: &ElementKind, line: usize, word: &str) -> Diagnostic {
6638− let name = element_kind_name(kind);
6639− let (what, instead) = match kind.layout() {
6641− "is text, whose lines and children flow together with no gap between them",
6642− "; to space the children out, put them in an @el or @row",
6644− Layout::Void => ("has no content to lay out", ""),
6646− "keeps HTML's own layout",
6647− "; for a flex layout of your own, write CSS, such as `display flex, gap 8`",
6654− "'{0}' can't go on {1}: {1} {2}. `{0}` works on a row, column or grid \
6655− (@el, @row, @grid, @section, ...){3}",
6656− word, name, what, instead
6662−/// Diagnostics about an element a function's body wrote are reported at
3006+ validate_tree(&elem.children, Some(&elem.kind), diagnostics);
6663−/// the call (see `belongs_to_call`); say which body the element is in.
6664−fn in_function_body(elem: &Element, diagnostics: &mut [Diagnostic]) {
6665− if let Some(function) = &elem.function {
6666− for d in diagnostics {
6667− d.message = format!("{}\n in the body of @{}", d.message, function);
6672−/// Report each diagnostic once: a line that runs many times (in a loop, in
6673−/// a function called from one place many times) reports its problems once.
6674−fn dedupe(diagnostics: &mut Vec<Diagnostic>) {
6675− let mut seen = HashSet::new();
6676− diagnostics.retain(|d| {
6687fn relative_luminance(r: u8, g: u8, b: u8) -> f64 {
3011fn relative_luminance(r: u8, g: u8, b: u8) -> f64 {
6688 fn linearize(c: u8) -> f64 {
3012 fn linearize(c: u8) -> f64 {
6689 let s = c as f64 / 255.0;
3013 let s = c as f64 / 255.0;
@@ -6696,24 +3020,6 @@ fn relative_luminance(r: u8, g: u8, b: u8) -> f64 {
6696 0.2126 * linearize(r) + 0.7152 * linearize(g) + 0.0722 * linearize(b)
3020 0.2126 * linearize(r) + 0.7152 * linearize(g) + 0.0722 * linearize(b)
6699−/// The red, green and blue of a `#rgb` or `#rrggbb` colour.
6700−fn parse_hex_rgb(s: &str) -> Option<(u8, u8, u8)> {
6701− let s = s.strip_prefix('#')?;
6702− if !s.bytes().all(|b| b.is_ascii_hexdigit()) {
6705− let channel = |i: usize, len: usize| u8::from_str_radix(&s[i..i + len], 16).ok();
6708− channel(0, 1)? * 17,
6709− channel(1, 1)? * 17,
6710− channel(2, 1)? * 17,
6712− 6 => Some((channel(0, 2)?, channel(2, 2)?, channel(4, 2)?)),
6717fn contrast_ratio(c1: (u8, u8, u8), c2: (u8, u8, u8)) -> f64 {
3023fn contrast_ratio(c1: (u8, u8, u8), c2: (u8, u8, u8)) -> f64 {
6718 let l1 = relative_luminance(c1.0, c1.1, c1.2);
3024 let l1 = relative_luminance(c1.0, c1.1, c1.2);
6719 let l2 = relative_luminance(c2.0, c2.1, c2.2);
3025 let l2 = relative_luminance(c2.0, c2.1, c2.2);
@@ -6721,48 +3027,65 @@ fn contrast_ratio(c1: (u8, u8, u8), c2: (u8, u8, u8)) -> f64 {
6721 (lighter + 0.05) / (darker + 0.05)
3027 (lighter + 0.05) / (darker + 0.05)
3030+// ---------------------------------------------------------------------------
3031+// Variable substitution
3032+// ---------------------------------------------------------------------------
3034+/// Interpolate `$name` variables and `${expr}` expressions into text.
3035+/// Undefined variables, and expressions that don't evaluate, are left as
3036+/// written so they show up in the output.
3037+fn substitute_vars(input: &str, vars: &HashMap<String, String>) -> String {
3038+ if !input.contains('$') {
3039+ return input.to_string();
3041+ let is_name_char = |c: char| c.is_alphanumeric() || matches!(c, '_' | '-' | '.');
3042+ let mut result = String::with_capacity(input.len());
3043+ let mut rest = input;
3044+ while let Some(pos) = rest.find('$') {
3045+ result.push_str(&rest[..pos]);
3046+ let after = &rest[pos + 1..];
3047+ if after.starts_with('{')
3048+ && let Some(close) = matching_brace(after)
3050+ let source = &after[1..close];
3051+ match crate::expr::eval(source, &|name: &str| lookup(vars, name)) {
3052+ Ok(value) => result.push_str(&value.to_string()),
3053+ Err(_) => result.push_str(&rest[pos..pos + 1 + close + 1]),
3055+ rest = &after[close + 1..];
3058+ let mut end = after.find(|c: char| !is_name_char(c)).unwrap_or(after.len());
3059+ while end > 0 && after[..end].ends_with('.') {
3062+ let name = &after[..end];
3063+ match vars.get(name) {
3064+ Some(value) if !name.is_empty() => result.push_str(value),
3067+ result.push_str(name);
3070+ rest = &after[end..];
3072+ result.push_str(rest);
6724/// `@image [inline] icon.svg` becomes the SVG's markup, with `width`,
3076/// `@image [inline] icon.svg` becomes the SVG's markup, with `width`,
6725−/// `height`, `color` / `fill` and the HTML attributes (`class=`, `id=`,
3077+/// `height`, `color` / `fill`, `class=` and `id=` applied to the `<svg>`
6726−/// `aria-label=`, ...) applied to the `<svg>` tag; any other attribute is
3078+/// tag. Other nodes are returned unchanged.
6727−/// an error. Other nodes are returned unchanged.
6728fn inline_svg(node: Node, line_num: usize, ctx: &mut ParseContext) -> Node {
3079fn inline_svg(node: Node, line_num: usize, ctx: &mut ParseContext) -> Node {
6729 let Node::Element(elem) = &node else {
3080 let Node::Element(elem) = &node else {
6730 return node;
3081 return node;
6732− let inline = elem.kind == ElementKind::Image
3083+ let is_inline_svg = elem.kind == ElementKind::Image
6733 && elem.attrs.iter().any(|a| a.key == "inline" && !a.html)
3084 && elem.attrs.iter().any(|a| a.key == "inline" && !a.html)
6734− && elem.argument.as_deref().is_some_and(|src| !src.is_empty());
3085+ && elem.argument.as_deref().is_some_and(|src| src.ends_with(".svg"));
6735− if !inline {
3086+ if !is_inline_svg {
6736 return node;
3087 return node;
6738− // A raster image: its file, read relative to this one, as a `data:` URI
6742− .is_some_and(|src| src.ends_with(".svg"))
6744− let Node::Element(mut elem) = node else {
6747− let filename = elem.argument.clone().unwrap_or_default();
6748− let resolved = ctx.resolve(&filename);
6749− match std::fs::read(&resolved) {
6751− elem.argument = Some(crate::codegen::data_uri(&filename, &data));
6752− ctx.included_files.push(resolved);
6754− Err(e) => ctx.diagnostics.push(Diagnostic::new(
6755− code::UNREADABLE_FILE,
6759− "cannot load image '{}' to put it into the page: {}",
6764− return Node::Element(elem);
6766 let filename = elem.argument.clone().unwrap_or_default();
3089 let filename = elem.argument.clone().unwrap_or_default();
6767 let resolved = match &ctx.base_path {
3090 let resolved = match &ctx.base_path {
6768 Some(base) => base.join(&filename),
3091 Some(base) => base.join(&filename),
@@ -6771,104 +3094,104 @@ fn inline_svg(node: Node, line_num: usize, ctx: &mut ParseContext) -> Node {
6771 let mut svg = match std::fs::read_to_string(&resolved) {
3094 let mut svg = match std::fs::read_to_string(&resolved) {
6772 Ok(text) => text.trim().to_string(),
3095 Ok(text) => text.trim().to_string(),
6773 Err(e) => {
3096 Err(e) => {
6774− ctx.diagnostics.push(Diagnostic::new(
3097+ ctx.diagnostics.push(Diagnostic {
6775− code::UNREADABLE_FILE,
3098+ line: line_num,
6776− Severity::Error,
3099+ column: None,
6777− line_num,
3100+ message: format!("cannot load SVG '{}': {}", filename, e),
6778− format!("cannot load SVG '{}': {}", filename, e),
3101+ severity: Severity::Error,
6779− ));
3102+ source_line: None,
6780 return node;
3104 return node;
6783 ctx.included_files.push(resolved);
3107 ctx.included_files.push(resolved);
6784− // The file's markup has no class of its own, so a style reaches it only
6785− // as one of the root's attributes: anything else is reported, never
6786− // left out silently
6787− let mut left_out: Vec<String> = Vec::new();
6788− // The styles go in the root's `style=`, where a length takes its unit
6789− // and `var(--name)` works, as in any CSS
6790− let mut style: Vec<String> = Vec::new();
6791 for attr in &elem.attrs {
3108 for attr in &elem.attrs {
6792− let target = match (attr.key.as_str(), attr.html, &attr.value) {
3109+ let Some(value) = &attr.value else { continue };
6793− ("inline", false, None) | ("src", true, _) => continue,
3110+ let target = match (attr.key.as_str(), attr.html) {
6794− // `fill` and `shrink` are layout words, which need a class
3111+ ("width", false) | ("height", false) => attr.key.as_str(),
6795− ("width" | "height", false, Some(value))
3112+ ("color", false) | ("fill", false) => "fill",
6796− if matches!(value.as_str(), "fill" | "shrink") =>
3113+ ("class", true) | ("id", true) => attr.key.as_str(),
6797− {
3114+ _ => continue,
6798− left_out.push(format!("{} {}", attr.key, value));
6801− ("width" | "height", false, Some(value)) => {
6802− let value = crate::vocab::with_px(&attr.key, value);
6803− style.push(format!("{}:{}", attr.key, value));
6806− ("color" | "fill", false, Some(value)) => {
6807− style.push(format!("fill:{}", value));
6810− ("style", true, Some(value)) => {
6811− style.insert(0, value.trim().trim_end_matches(';').to_string());
6814− ("alt", true, _) => {
6815− left_out.push("alt".to_string());
6818− (key, true, Some(_)) => key,
6819− (key, false, None) if crate::vocab::is_html_flag(key) => key,
6821− left_out.push(attr.key.clone());
6825− let value = attr.value.as_deref().unwrap_or("");
3116+ svg = set_svg_attr(&svg, target, value);
6826− svg = set_svg_attr(&svg, target, &html_escape_md(value));
6828− if !style.is_empty() {
3118+ Node::Raw(svg)
6829− // After the file's own `style=`, which stays: these come later, so
3119+}
6830− // they win where both set a property
3120+
6831− let mut value = html_escape_md(&style.join(";"));
3121+/// The first `$name|filter` (old filter syntax) in `text`, as (name, filter).
6832− if let Some(own) = svg_attr_value(&svg, "style")
3122+fn old_filter_syntax(text: &str) -> Option<(String, String)> {
6833− .map(|range| svg[range].trim().trim_end_matches(';').to_string())
3123+ const FILTERS: &[&str] = &[
6834− .filter(|own| !own.is_empty())
3124+ "uppercase", "lowercase", "capitalize", "trim", "length", "reverse", "truncate",
6835− {
3125+ "replace", "default", "lighten", "darken", "alpha", "mix",
6836− value = format!("{};{}", own, value);
3126+ ];
3127+ let mut rest = text;
3128+ while let Some(pos) = rest.find('$') {
3129+ let after = &rest[pos + 1..];
3131+ .find(|c: char| !(c.is_alphanumeric() || matches!(c, '_' | '-' | '.')))
3132+ .unwrap_or(after.len());
3133+ if let Some(filter) = after[end..].strip_prefix('|') {
3134+ let name_end = filter.find(|c: char| !c.is_ascii_alphabetic()).unwrap_or(filter.len());
3135+ if end > 0 && FILTERS.contains(&&filter[..name_end]) {
3136+ return Some((after[..end].to_string(), filter[..name_end].to_string()));
6838− svg = set_svg_attr(&svg, "style", &value);
3139+ rest = &after[end..];
6840− if !left_out.is_empty() {
3141+ None
6841− let alt = left_out.iter().any(|name| name == "alt");
3142+}
6842− let names = left_out
3143+
6843− .iter()
3144+/// Index of the `}` matching the `{` that `s` starts with (skipping
6844− .map(|name| format!("'{}'", name))
3145+/// braces inside string literals).
6845− .collect::<Vec<_>>()
3146+fn matching_brace(s: &str) -> Option<usize> {
6846− .join(", ");
3147+ let mut depth = 0;
6847− let mut message = format!(
3148+ let mut in_string = false;
6848− "{} can't go on an inline SVG: `@image [inline]` puts the file's own markup into the page, which takes `width` and `height` as lengths, `color` or `fill` (as its fill) and HTML attributes (`class=`, `aria-label=`, ...)",
3149+ for (i, c) in s.char_indices() {
6849− names
3150+ match c {
6850− );
3151+ '"' => in_string = !in_string,
6851− if alt {
3152+ _ if in_string => {}
6852− message.push_str("; an SVG has no alt text: name it with `aria-label=` and `role=img`");
3153+ '{' => depth += 1,
6854− ctx.diagnostics.push(Diagnostic::new(
6855− code::UNEXPECTED_ARGUMENT,
6861− Node::Raw(svg)
3163+ None
6864// ---------------------------------------------------------------------------
3166// ---------------------------------------------------------------------------
6865// Variable usage tracking
3167// Variable usage tracking
6866// ---------------------------------------------------------------------------
3168// ---------------------------------------------------------------------------
6868−/// Record the names a string refers to (by syntax) as used.
3170+/// Scan a string for $name references and record them in the used set.
6869fn track_var_refs(input: &str, used: &mut HashSet<String>) {
3171fn track_var_refs(input: &str, used: &mut HashSet<String>) {
6870− if input.contains('$') {
3172+ if !input.contains('$') {
6871− used.extend(interp::names(input).into_iter().map(String::from));
3173+ return;
3175+ let chars: Vec<char> = input.chars().collect();
3177+ while i < chars.len() {
3179+ && i + 1 < chars.len()
3180+ && (chars[i + 1].is_alphanumeric() || chars[i + 1] == '_' || chars[i + 1] == '-')
3183+ let mut end = start;
3184+ while end < chars.len()
3185+ && (chars[end].is_alphanumeric() || chars[end] == '-' || chars[end] == '_')
3189+ let name: String = chars[start..end].iter().collect();
@@ -6876,63 +3199,49 @@ fn track_var_refs(input: &str, used: &mut HashSet<String>) {
6876// Unused definition warnings
3199// Unused definition warnings
6877// ---------------------------------------------------------------------------
3200// ---------------------------------------------------------------------------
6879−/// Warn about definitions nothing uses, except `exported` ones (the
3202+fn check_unused(ctx: &mut ParseContext) {
6880−/// definitions of a library, for the files that include it).
6881−fn check_unused(ctx: &mut ParseContext, exported: &HashSet<String>) {
6882 // Check unused @let variables
3203 // Check unused @let variables
6883 for (name, &line) in &ctx.let_lines {
3204 for (name, &line) in &ctx.let_lines {
6884− if exported.contains(name) {
3205+ if name.starts_with("--") {
6885− // A library's names are for other files (a custom property
3206+ continue; // CSS vars are always used
6886− // isn't a variable, so it is never listed here)
6889 if !ctx.used_variables.contains(name) {
3208 if !ctx.used_variables.contains(name) {
6890− ctx.diagnostics.push(
3209+ ctx.diagnostics.push(Diagnostic {
6891− Diagnostic::new(
3210+ line,
6892− code::UNUSED_VARIABLE,
3211+ column: None,
6893− Severity::Warning,
3212+ message: format!("unused variable '${}' (defined but never referenced)", name),
6894− line,
3213+ severity: Severity::Warning,
6895− format!("unused variable '${}' (defined but never referenced)", name),
3214+ source_line: None,
6897− .subject(name.as_str()),
6902− // Check unused attribute bundles (@let name [...]). A `$name` in code
3219+ // Check unused attribute bundles (@let name [...])
6903− // that doesn't run (an `if()` branch or `@if` not taken) counts too.
6904 for (name, &line) in &ctx.define_lines {
3220 for (name, &line) in &ctx.define_lines {
6905− if !ctx.used_defines.contains(name)
3221+ if !ctx.used_defines.contains(name) {
6906− && !ctx.used_variables.contains(name)
3222+ ctx.diagnostics.push(Diagnostic {
6907− && !exported.contains(name)
3223+ line,
6908− {
3224+ column: None,
6909− ctx.diagnostics.push(
3225+ message: format!(
6910− Diagnostic::new(
3226+ "unused attribute bundle '${}' (defined but never referenced)",
6911− code::UNUSED_BUNDLE,
3227+ name
6912− Severity::Warning,
3228+ ),
6913− line,
3229+ severity: Severity::Warning,
6914− format!(
3230+ source_line: None,
6915− "unused attribute bundle '${}' (defined but never referenced)",
3231+ });
6919− .subject(name.as_str()),
6924 // Check unused functions (@let name ... with body)
3235 // Check unused functions (@let name ... with body)
6925 for (name, &line) in &ctx.fn_lines {
3236 for (name, &line) in &ctx.fn_lines {
6926− if !ctx.used_functions.contains(name) && !exported.contains(name) {
3237+ if !ctx.used_functions.contains(name) {
6927− ctx.diagnostics.push(
3238+ ctx.diagnostics.push(Diagnostic {
6928− Diagnostic::new(
3239+ line,
6929− code::UNUSED_FUNCTION,
3240+ column: None,
6930− Severity::Warning,
3241+ message: format!("unused function '@{}' (defined but never called)", name),
6931− line,
3242+ severity: Severity::Warning,
6932− format!("unused function '@{}' (defined but never called)", name),
3243+ source_line: None,
6934− .subject(name.as_str()),
@@ -7018,6 +3327,34 @@ fn parse_json_with_error(input: &str) -> Result<JsonValue, String> {
3330+/// Visit the lines of a block in source order, children after their line.
3331+fn for_each_line<'a>(block: &'a [Syntax], f: &mut impl FnMut(&'a Syntax)) {
3332+ for node in block {
3334+ if let Syntax::Line { children, .. } = node {
3335+ for_each_line(children, f);
3340+/// The text of a block whose lines are content, not htmlang (`@head`,
3341+/// `@style`, `@markdown`): each line trimmed, verbatim text as is.
3342+fn block_text(block: &[Syntax]) -> String {
3343+ let mut text = String::new();
3344+ for_each_line(block, &mut |node| match node {
3345+ Syntax::Line { text: line, .. } => {
3346+ text.push_str(line.trim());
3349+ Syntax::Raw { text: raw, .. } => {
3350+ text.push_str(raw);
7021fn parse_json_value(chars: &[char], mut pos: usize) -> Option<(JsonValue, usize)> {
3358fn parse_json_value(chars: &[char], mut pos: usize) -> Option<(JsonValue, usize)> {
7022 pos = skip_ws(chars, pos);
3359 pos = skip_ws(chars, pos);
7023 if pos >= chars.len() {
3360 if pos >= chars.len() {
@@ -7198,21 +3535,68 @@ fn skip_ws(chars: &[char], mut pos: usize) -> usize {
7201−/// A JSON value as an htmlang value: an object is a record, an array a
3538+/// Flatten a JSON value into variable assignments.
7202−/// list, a string text (never quoted text), `null` empty. A number keeps
3539+/// - Top-level object: each key becomes `prefix.key`
7203−/// the text it is written with (`1.50`), and reads as a number.
3540+/// - Top-level array: `prefix` becomes comma-separated, `prefix._count` set
7204−fn json_value(json: JsonValue) -> Value {
3541+/// - Array of objects: each item becomes space-separated values for @each destructuring
7205− match json {
3542+fn flatten_json(prefix: &str, value: &JsonValue, vars: &mut HashMap<String, String>) {
7206− JsonValue::Null => Value::empty(),
3543+ match value {
7207− JsonValue::Bool(b) => Value::Bool(b),
3544+ JsonValue::Str(s) => {
7208− JsonValue::Number(n) | JsonValue::Str(n) => Value::Str(n),
3545+ vars.insert(prefix.to_string(), s.clone());
7209− JsonValue::Array(items) => Value::list(items.into_iter().map(json_value).collect()),
3546+ }
7210− JsonValue::Object(pairs) => Value::Record(Rc::new(
3547+ JsonValue::Number(n) => {
7211− pairs
3548+ vars.insert(prefix.to_string(), n.clone());
7212− .into_iter()
3549+ }
7213− .map(|(key, value)| (key, json_value(value)))
3550+ JsonValue::Bool(b) => {
3551+ vars.insert(prefix.to_string(), b.to_string());
3553+ JsonValue::Null => {
3554+ vars.insert(prefix.to_string(), String::new());
3556+ JsonValue::Object(pairs) => {
3557+ for (key, val) in pairs {
3558+ flatten_json(&format!("{}.{}", prefix, key), val, vars);
3561+ JsonValue::Array(items) => {
3562+ // A list: its length under `NAME#` (see `lookup`), its text
3563+ // items joined as its value, and each item as `NAME.INDEX`
3564+ vars.insert(format!("{}#", prefix), items.len().to_string());
3565+ let text: Vec<String> = items
3567+ .map(json_value_to_string)
3568+ .filter(|s| !s.is_empty())
3570+ vars.insert(prefix.to_string(), text.join(", "));
3571+ // Also set indexed access: prefix.0, prefix.1, etc.
3572+ for (i, item) in items.iter().enumerate() {
3573+ flatten_json(&format!("{}.{}", prefix, i), item, vars);
3579+/// Resolve `$name` for an expression: a list if `name` was loaded from a
3580+/// JSON array, else its text.
3581+fn lookup(vars: &HashMap<String, String>, name: &str) -> Option<crate::expr::Value> {
3582+ use crate::expr::Value;
3583+ match vars.get(&format!("{}#", name)).and_then(|n| n.parse::<usize>().ok()) {
3584+ Some(len) => Some(Value::List(
3586+ .map(|i| vars.get(&format!("{}.{}", name, i)).cloned().unwrap_or_default())
7214 .collect(),
3587 .collect(),
3589+ None => vars.get(name).cloned().map(Value::Str),
3593+fn json_value_to_string(v: &JsonValue) -> String {
3595+ JsonValue::Str(s) => s.clone(),
3596+ JsonValue::Number(n) => n.clone(),
3597+ JsonValue::Bool(b) => b.to_string(),
3598+ JsonValue::Null => String::new(),
3599+ JsonValue::Array(_) | JsonValue::Object(_) => String::new(),
@@ -7220,29 +3604,6 @@ fn json_value(json: JsonValue) -> Value {
7220// SVG attribute injection helper
3604// SVG attribute injection helper
7221// ---------------------------------------------------------------------------
3605// ---------------------------------------------------------------------------
7223−/// Where the root `<svg ...>` tag's `attr_name="..."` value is, as a byte
7224−/// range of `svg`. Only the opening tag is read, so a child's attribute is
7225−/// never found, and the name must follow whitespace, so `width` doesn't
7226−/// match `stroke-width`.
7227−fn svg_attr_value(svg: &str, attr_name: &str) -> Option<std::ops::Range<usize>> {
7228− let tag_start = svg.find("<svg")?;
7229− let tag_end = svg[tag_start..]
7231− .map(|p| tag_start + p)
7232− .unwrap_or(svg.len());
7233− let tag = &svg[tag_start..tag_end];
7234− let pattern = format!("{}=\"", attr_name);
7235− let (pos, _) = tag.match_indices(&pattern).find(|(pos, _)| {
7239− .is_some_and(char::is_whitespace)
7241− let value_start = tag_start + pos + pattern.len();
7242− let end = svg[value_start..tag_end].find('"')?;
7243− Some(value_start..value_start + end)
7246fn set_svg_attr(svg: &str, attr_name: &str, value: &str) -> String {
3607fn set_svg_attr(svg: &str, attr_name: &str, value: &str) -> String {
7247 // Only the opening <svg ...> tag is touched, so child attributes such as
3608 // Only the opening <svg ...> tag is touched, so child attributes such as
7248 // `stroke-width` are left alone.
3609 // `stroke-width` are left alone.
@@ -7253,14 +3614,26 @@ fn set_svg_attr(svg: &str, attr_name: &str, value: &str) -> String {
7253 .find('>')
3614 .find('>')
7254 .map(|p| tag_start + p)
3615 .map(|p| tag_start + p)
7255 .unwrap_or(svg.len());
3616 .unwrap_or(svg.len());
3617+ let tag = &svg[tag_start..tag_end];
7257− // Replace an existing attribute
3619+ // Replace an existing attribute (must be preceded by whitespace so that
7258− if let Some(existing) = svg_attr_value(svg, attr_name) {
3620+ // `width` doesn't match `stroke-width`).
7259− let mut result = String::with_capacity(svg.len());
3621+ let pattern = format!("{}=\"", attr_name);
7260− result.push_str(&svg[..existing.start]);
3622+ let existing = tag.match_indices(&pattern).find(|(pos, _)| {
7261− result.push_str(value);
3623+ tag[..*pos]
7262− result.push_str(&svg[existing.end..]);
3624+ .chars()
7263− return result;
3625+ .next_back()
3626+ .is_some_and(char::is_whitespace)
3628+ if let Some((pos, _)) = existing {
3629+ let value_start = tag_start + pos + pattern.len();
3630+ if let Some(end) = svg[value_start..tag_end].find('"') {
3631+ let mut result = String::with_capacity(svg.len());
3632+ result.push_str(&svg[..value_start]);
3633+ result.push_str(value);
3634+ result.push_str(&svg[value_start + end..]);
7266 // Otherwise inject it into the opening tag (before a self-closing `/`).
3639 // Otherwise inject it into the opening tag (before a self-closing `/`).
@@ -7583,10 +3956,7 @@ mod tests {
7584 fn parses_page_directive() {
3957 fn parses_page_directive() {
7585 let r = parse_ok("@page My Title\n");
3958 let r = parse_ok("@page My Title\n");
7586− assert_eq!(
3959+ assert_eq!(r.document.page_title.as_deref(), Some("My Title"));
7587− r.document.page.map(|p| p.title).as_deref(),