5cdd429 · htmlang · git.iko.soy

git.iko.soy/htmlang

Add @mixin, @assert directives, CSS math functions, and CLI tools

Implement 11 improvements: - @mixin directive with spread syntax for composable style groups - @assert directive for compile-time design system constraints - CSS math functions (clamp, min, max) passthrough without px appending - htmlang doctor, migrate, benchmark CLI commands - LSP semantic token modifiers for unused variable dimming - Snippet completions with tab stops for @fn parameters - Comprehensive snapshot and unit test coverage (25+ new tests)

commit5cdd429363b2df247e4c5bd4f4b45e36bacbe2be authoriko <mail@iko.soy> dateWed 15 Apr 2026, 17:03 (6 months ago) parent39f698d

9 files changed+599−16

compare with master

unifiedsplit

DESIGN.md+24 src/bin/htmlang-lsp.rs+124−15 src/codegen.rs+1−1 src/main.rs+207 src/parser.rs+73 tests/snapshots.rs+146 tests/snapshots/assert_directive.hl+10 tests/snapshots/clamp_css.hl+4 tests/snapshots/mixin_spread.hl+10

DESIGN.md+24

@@ -219,6 +219,30 @@ Creates a named attribute bundle. Referenced with `$name` inside attribute lists

219219

220220Attributes listed after `$name` override those in the definition.

221221

222+### `@mixin`

223+

224+Creates a composable style group. Like `@define`, but intended for reusable style patterns. Referenced with `...$name` (spread syntax) or `$name` inside attribute lists.

225+

226+```

227+@mixin card-style [padding 20, rounded 8, background white]

228+@mixin interactive [cursor pointer, hover:background #e5e7eb, transition all 0.15s ease]

229+

230+@el [...$card-style, ...$interactive, border 1 #ccc]

231+ Composed styles from two mixins

232+```

233+

234+### `@assert`

235+

236+Compile-time assertion. If the condition is false, a compile error is emitted. Useful for enforcing design system constraints.

237+

238+```

239+@let spacing 16

240+@let primary #3b82f6

241+

242+@assert $spacing == 16

243+@assert $primary != red

244+```

245+

222246### `@fn`

223247

224248Defines a pure function (reusable component). Parameters are prefixed with `$`. Default values can be specified with `=`.

src/bin/htmlang-lsp.rs+124−15

@@ -89,7 +89,9 @@ impl LanguageServer for Backend {

8989 SemanticTokenType::COMMENT,

9090 SemanticTokenType::PROPERTY,

9191 ],

92− token_modifiers: vec![],

92+ token_modifiers: vec![

93+ SemanticTokenModifier::new("deprecated"), // bit 0 = 1 → dimmed/strikethrough

94+ ],

9395 },

9496 full: Some(SemanticTokensFullOptions::Bool(true)),

9597 range: None,

@@ -700,6 +702,8 @@ fn directive_completions(range: Range) -> Vec<CompletionItem> {

700702 ("@base", "Set base URL for relative links", "@base "),

701703 ("@font-face", "Define a custom font face", "@font-face"),

702704 ("@json-ld", "Add JSON-LD structured data to head", "@json-ld"),

705+ ("@mixin", "Define a composable style group (use with ...$name)", "@mixin "),

706+ ("@assert", "Compile-time assertion for variable values", "@assert "),

703707 ]

704708 .iter()

705709 .map(|(name, detail, insert)| {

@@ -1328,19 +1332,39 @@ fn function_completions(text: &str, range: Range) -> Vec<CompletionItem> {

13281332 if let Some(rest) = trimmed.strip_prefix("@fn ") {

13291333 let parts: Vec<&str> = rest.split_whitespace().collect();

13301334 if let Some(name) = parts.first() {

1331− let params = parts[1..].join(" ");

1335+ let params: Vec<&str> = parts[1..].iter()

1336+ .map(|p| p.strip_prefix('$').unwrap_or(p))

1337+ .collect();

13321338 let detail = if params.is_empty() {

13331339 "Function".to_string()

13341340 } else {

1335− format!("Function({})", params)

1341+ format!("Function({})", params.join(", "))

13361342 };

1337− items.push(item(

1338− &format!("@{}", name),

1339− CompletionItemKind::FUNCTION,

1340− &detail,

1341− &format!("@{}", name),

1342− range,

1343− ));

1343+ // Generate snippet with tab stops for parameters

1344+ let insert_text = if params.is_empty() {

1345+ format!("@{}", name)

1346+ } else {

1347+ let param_snippets: Vec<String> = params.iter().enumerate().map(|(i, p)| {

1348+ let p_name = p.split('=').next().unwrap_or(p);

1349+ let default = p.split('=').nth(1).unwrap_or(p_name);

1350+ format!("{} ${{{}:{}}}", p_name, i + 1, default)

1351+ }).collect();

1352+ format!("@{} [{}]", name, param_snippets.join(", "))

1353+ };

1354+ let mut ci = CompletionItem {

1355+ label: format!("@{}", name),

1356+ kind: Some(CompletionItemKind::FUNCTION),

1357+ detail: Some(detail),

1358+ text_edit: Some(CompletionTextEdit::Edit(TextEdit {

1359+ range,

1360+ new_text: insert_text,

1361+ })),

1362+ ..Default::default()

1363+ };

1364+ if !params.is_empty() {

1365+ ci.insert_text_format = Some(tower_lsp::lsp_types::InsertTextFormat::SNIPPET);

1366+ }

1367+ items.push(ci);

13441368 }

13451369 }

13461370 }

@@ -2485,6 +2509,42 @@ fn code_actions(

24852509 }

24862510 }

24872511

2512+ // Quick-fix: remove unused @mixin

2513+ if msg.contains("unused mixin") {

2514+ let line = diag.range.start.line as usize;

2515+ let lines: Vec<&str> = text.lines().collect();

2516+ if let Some(source_line) = lines.get(line) {

2517+ let trimmed = source_line.trim_start();

2518+ if trimmed.starts_with("@mixin ") {

2519+ let mixin_name = trimmed.strip_prefix("@mixin ")

2520+ .and_then(|r| {

2521+ let r = r.trim();

2522+ r.find('[').map(|b| r[..b].trim()).or_else(|| r.split_whitespace().next())

2523+ })

2524+ .unwrap_or("?");

2525+ let edit = TextEdit {

2526+ range: Range::new(

2527+ Position::new(diag.range.start.line, 0),

2528+ Position::new(diag.range.start.line + 1, 0),

2529+ ),

2530+ new_text: String::new(),

2531+ };

2532+ let mut changes = HashMap::new();

2533+ changes.insert(uri.clone(), vec![edit]);

2534+ actions.push(CodeActionOrCommand::CodeAction(CodeAction {

2535+ title: format!("Remove unused mixin '{}'", mixin_name),

2536+ kind: Some(CodeActionKind::QUICKFIX),

2537+ diagnostics: Some(vec![diag.clone()]),

2538+ edit: Some(WorkspaceEdit {

2539+ changes: Some(changes),

2540+ ..Default::default()

2541+ }),

2542+ ..Default::default()

2543+ }));

2544+ }

2545+ }

2546+ }

2547+

24882548 // Quick-fix: add alt attribute to @image

24892549 if msg.contains("@image should have") && msg.contains("alt") {

24902550 let line = diag.range.start.line as usize;

@@ -2929,6 +2989,44 @@ fn semantic_tokens(text: &str) -> Vec<SemanticToken> {

29292989 let mut prev_line: u32 = 0;

29302990 let mut prev_start: u32 = 0;

29312991

2992+ // Build set of unused variables by parsing diagnostics

2993+ let result = htmlang::parser::parse(text);

2994+ let mut unused_vars: std::collections::HashSet<String> = std::collections::HashSet::new();

2995+ for d in &result.diagnostics {

2996+ if d.message.contains("unused variable '$") {

2997+ if let Some(start) = d.message.find("'$") {

2998+ let rest = &d.message[start + 2..];

2999+ if let Some(end) = rest.find('\'') {

3000+ unused_vars.insert(rest[..end].to_string());

3001+ }

3002+ }

3003+ }

3004+ if d.message.contains("unused function '@") {

3005+ if let Some(start) = d.message.find("'@") {

3006+ let rest = &d.message[start + 2..];

3007+ if let Some(end) = rest.find('\'') {

3008+ unused_vars.insert(format!("@{}", &rest[..end]));

3009+ }

3010+ }

3011+ }

3012+ if d.message.contains("unused define '$") {

3013+ if let Some(start) = d.message.find("'$") {

3014+ let rest = &d.message[start + 2..];

3015+ if let Some(end) = rest.find('\'') {

3016+ unused_vars.insert(rest[..end].to_string());

3017+ }

3018+ }

3019+ }

3020+ if d.message.contains("unused mixin '") {

3021+ if let Some(start) = d.message.find("unused mixin '") {

3022+ let rest = &d.message[start + 14..];

3023+ if let Some(end) = rest.find('\'') {

3024+ unused_vars.insert(rest[..end].to_string());

3025+ }

3026+ }

3027+ }

3028+ }

3029+

29323030 for (line_idx, line) in text.lines().enumerate() {

29333031 let trimmed = line.trim();

29343032 let line_num = line_idx as u32;

@@ -2936,7 +3034,7 @@ fn semantic_tokens(text: &str) -> Vec<SemanticToken> {

29363034 // Detect comments

29373035 if trimmed.starts_with("--") {

29383036 let col = (line.len() - trimmed.len()) as u32;

2939− push_token(&mut tokens, &mut prev_line, &mut prev_start, line_num, col, trimmed.len() as u32, 4);

3037+ push_token(&mut tokens, &mut prev_line, &mut prev_start, line_num, col, trimmed.len() as u32, 4, 0);

29403038 continue;

29413039 }

29423040

@@ -2957,13 +3055,20 @@ fn semantic_tokens(text: &str) -> Vec<SemanticToken> {

29593057 | "@unless" | "@og" | "@breakpoint"

2960− | "@canonical" | "@base" | "@font-face" | "@json-ld" => 0, // keyword

3058+ | "@canonical" | "@base" | "@font-face" | "@json-ld"

3060+ | "@use" => 0, // keyword

29613061 _ => {

29623062 // Check if it's a user function call (starts with @ but not a builtin element)

29633063 if is_builtin_element(word) { 0 } else { 2 } // function

29643064 }

29653065 };

2966− push_token(&mut tokens, &mut prev_line, &mut prev_start, line_num, start as u32, (i - start) as u32, token_type);

3066+ // Mark unused @fn definitions with deprecated modifier (dimmed)

3067+ let modifier = if (trimmed.starts_with("@fn ") || trimmed.starts_with("@define ") || trimmed.starts_with("@mixin ")) && word != "@fn" && word != "@define" && word != "@mixin" {

3068+ let name_part = &word[1..]; // strip @

3069+ if unused_vars.contains(&format!("@{}", name_part)) { 1 } else { 0 }

3070+ } else { 0 };

3071+ push_token(&mut tokens, &mut prev_line, &mut prev_start, line_num, start as u32, (i - start) as u32, token_type, modifier);

29673072 } else if bytes[i] == b'$' {

29683073 let start = i;

29693074 i += 1;

@@ -2971,7 +3076,10 @@ fn semantic_tokens(text: &str) -> Vec<SemanticToken> {

29713076 i += 1;

29723077 }

29733078 if i > start + 1 {

2974− push_token(&mut tokens, &mut prev_line, &mut prev_start, line_num, start as u32, (i - start) as u32, 1); // variable

3079+ // Check if this is an unused variable definition on a @let line

3080+ let var_name = &line[start + 1..i];

3081+ let modifier = if trimmed.starts_with("@let ") && unused_vars.contains(var_name) { 1 } else { 0 };

3082+ push_token(&mut tokens, &mut prev_line, &mut prev_start, line_num, start as u32, (i - start) as u32, 1, modifier); // variable

29753083 }

29763084 } else {

29773085 i += 1;

@@ -3005,6 +3113,7 @@ fn push_token(

30053113 start: u32,

30063114 length: u32,

30073115 token_type: u32,

3116+ token_modifiers_bitset: u32,

30083117) {

30093118 let delta_line = line - *prev_line;

30103119 let delta_start = if delta_line == 0 {

@@ -3017,7 +3126,7 @@ fn push_token(

30173126 delta_start,

30183127 length,

30193128 token_type,

3020− token_modifiers_bitset: 0,

3129+ token_modifiers_bitset,

30213130 });

30223131 *prev_line = line;

30233132 *prev_start = start;

src/codegen.rs+1−1

@@ -2371,7 +2371,7 @@ fn css_px(value: &str) -> String {

23712371 if CSS_UNITS.iter().any(|u| v.ends_with(u)) {

23722372 return v.to_string();

23732373 }

2374− if v.starts_with("var(") || v.starts_with("calc(") {

2374+ if v.starts_with("var(") || v.starts_with("calc(") || v.starts_with("clamp(") || v.starts_with("min(") || v.starts_with("max(") {

23752375 return v.to_string();

23762376 }

23772377 format!("{}px", v)

src/main.rs+207

@@ -223,6 +223,9 @@ Commands:

223223 playground [out.html] Generate a self-contained HTML playground

224224 clean [dir] Remove generated .html files

225225 outline <file.hl> Show document structure tree

226+ doctor Check toolchain health

227+ migrate [dir|file] Auto-upgrade deprecated syntax

228+ benchmark <file|dir> Measure compile time and output size

226229

227230Options:

228231 -w, --watch Watch for changes and recompile

@@ -1806,6 +1809,210 @@ document.getElementById('editor').addEventListener('keydown',e=>{if(e.key==='Ent

18061809 return;

18071810 }

18081811

1812+ // Handle "doctor" subcommand — check toolchain health

1813+ if args.len() >= 2 && args[1] == "doctor" {

1814+ eprintln!("htmlang doctor — checking toolchain health\n");

1815+ let mut ok = true;

1816+

1817+ // Check htmlang version

1818+ eprintln!(" htmlang: v{}", env!("CARGO_PKG_VERSION"));

1819+

1820+ // Check if htmlang-lsp binary is available

1821+ let lsp_status = process::Command::new("htmlang-lsp")

1822+ .arg("--version")

1823+ .output();

1824+ match lsp_status {

1825+ Ok(output) if output.status.success() => {

1826+ let ver = String::from_utf8_lossy(&output.stdout);

1827+ eprintln!(" htmlang-lsp: {}", ver.trim());

1828+ }

1829+ _ => {

1830+ eprintln!(" htmlang-lsp: not found (optional — needed for editor integration)");

1831+ }

1832+ }

1833+

1834+ // Check if cargo is available (for building from source)

1835+ let cargo_status = process::Command::new("cargo")

1836+ .arg("--version")

1837+ .output();

1838+ match cargo_status {

1839+ Ok(output) if output.status.success() => {

1840+ let ver = String::from_utf8_lossy(&output.stdout);

1841+ eprintln!(" cargo: {}", ver.trim());

1842+ }

1843+ _ => {

1844+ eprintln!(" cargo: not found");

1845+ ok = false;

1846+ }

1847+ }

1848+

1849+ // Check if git is available (for deploy)

1850+ let git_status = process::Command::new("git")

1851+ .arg("--version")

1852+ .output();

1853+ match git_status {

1854+ Ok(output) if output.status.success() => {

1855+ let ver = String::from_utf8_lossy(&output.stdout);

1856+ eprintln!(" git: {}", ver.trim());

1857+ }

1858+ _ => {

1859+ eprintln!(" git: not found (optional — needed for deploy)");

1860+ }

1861+ }

1862+

1863+ // Check for htmlang.toml in current directory

1864+ if Path::new("htmlang.toml").exists() {

1865+ eprintln!(" config: htmlang.toml found");

1866+ } else {

1867+ eprintln!(" config: no htmlang.toml (using defaults)");

1868+ }

1869+

1870+ // Check for .hl files

1871+ let hl_count = collect_hl_files_recursive(Path::new(".")).len();

1872+ eprintln!(" .hl files: {} found in current directory", hl_count);

1873+

1874+ eprintln!();

1875+ if ok {

1876+ eprintln!("all checks passed");

1877+ } else {

1878+ eprintln!("some checks failed — see above");

1879+ process::exit(1);

1880+ }

1881+ return;

1882+ }

1883+

1884+ // Handle "migrate" subcommand — auto-upgrade deprecated syntax

1885+ if args.len() >= 2 && args[1] == "migrate" {

1886+ let target = if args.len() >= 3 { &args[2] } else { "." };

1887+ let path = Path::new(target);

1888+ let hl_files = if path.is_dir() {

1889+ collect_hl_files_recursive(path)

1890+ } else {

1891+ vec![PathBuf::from(target)]

1892+ };

1893+ if hl_files.is_empty() {

1894+ eprintln!("no .hl files found in {}", target);

1895+ process::exit(1);

1896+ }

1897+ let mut total_changes = 0usize;

1898+ for file in &hl_files {

1899+ let input = match fs::read_to_string(file) {

1900+ Ok(s) => s,

1901+ Err(_) => continue,

1902+ };

1903+ let mut output = String::new();

1904+ let mut changes = 0usize;

1905+ for line in input.lines() {

1906+ let mut migrated = line.to_string();

1907+ // Migrate @divider -> @hr

1908+ if migrated.trim().starts_with("@divider") {

1909+ migrated = migrated.replace("@divider", "@hr");

1910+ changes += 1;

1911+ }

1912+ // Migrate @ul -> @list

1913+ if migrated.trim().starts_with("@ul") && !migrated.trim().starts_with("@unless") {

1914+ migrated = migrated.replacen("@ul", "@list", 1);

1915+ changes += 1;

1916+ }

1917+ // Migrate align-center -> center-x (common mistake)

1918+ if migrated.contains("align-center") {

1919+ migrated = migrated.replace("align-center", "center-x");

1920+ changes += 1;

1921+ }

1922+ output.push_str(&migrated);

1923+ output.push('\n');

1924+ }

1925+ // Remove trailing extra newline if original didn't end with one

1926+ if !input.ends_with('\n') && output.ends_with('\n') {

1927+ output.pop();

1928+ }

1929+ if changes > 0 {

1930+ match fs::write(file, &output) {

1931+ Ok(()) => {

1932+ eprintln!("migrated {} ({} change{})", file.display(), changes, if changes == 1 { "" } else { "s" });

1933+ total_changes += changes;

1934+ }

1935+ Err(e) => eprintln!("error: {}: {}", file.display(), e),

1936+ }

1937+ }

1938+ }

1939+ if total_changes == 0 {

1940+ eprintln!("no migrations needed");

1941+ } else {

1942+ eprintln!("\n{} total change(s) across {} file(s)", total_changes, hl_files.len());

1943+ }

1944+ return;

1945+ }

1946+

1947+ // Handle "benchmark" subcommand — measure compile time and output size

1948+ if args.len() >= 2 && args[1] == "benchmark" {

1949+ if args.len() < 3 {

1950+ eprintln!("usage: htmlang benchmark <file.hl | dir>");

1951+ process::exit(1);

1952+ }

1953+ let target = &args[2];

1954+ let path = Path::new(target);

1955+ let hl_files = if path.is_dir() {

1956+ collect_hl_files_recursive(path)

1957+ } else {

1958+ vec![PathBuf::from(target)]

1959+ };

1960+ if hl_files.is_empty() {

1961+ eprintln!("no .hl files found in {}", target);

1962+ process::exit(1);

1963+ }

1964+

1965+ let mut total_source = 0usize;

1966+ let mut total_output = 0usize;

1967+ let mut total_css_rules = 0usize;

1968+ let mut total_elements = 0usize;

1969+ let mut total_errors = 0usize;

1970+

1971+ let start = std::time::Instant::now();

1972+ for file in &hl_files {

1973+ let input = match fs::read_to_string(file) {

1974+ Ok(s) => s,

1975+ Err(_) => continue,

1976+ };

1977+ total_source += input.len();

1978+ let base = file.parent();

1979+ let result = htmlang::parser::parse_with_base(&input, base);

1980+ let has_errors = result.diagnostics.iter().any(|d| d.severity == htmlang::parser::Severity::Error);

1981+ if has_errors {

1982+ total_errors += 1;

1983+ continue;

1984+ }

1985+ let html = htmlang::codegen::generate(&result.document);

1986+ total_output += html.len();

1987+ total_css_rules += html.matches('{').count().saturating_sub(1);

1988+ let mut ec = 0;

1989+ let mut colors = std::collections::HashSet::new();

1990+ let mut fonts = std::collections::HashSet::new();

1991+ count_elements(&result.document.nodes, &mut ec, &mut colors, &mut fonts);

1992+ total_elements += ec;

1993+ }

1994+ let elapsed = start.elapsed();

1995+

1996+ eprintln!("--- benchmark results ---");

1997+ eprintln!(" files: {}", hl_files.len());

1998+ eprintln!(" compile time: {:.1}ms", elapsed.as_secs_f64() * 1000.0);

1999+ eprintln!(" source size: {} bytes", total_source);

2000+ eprintln!(" output size: {} bytes", total_output);

2001+ if total_source > 0 {

2002+ eprintln!(" ratio: {:.1}x", total_output as f64 / total_source as f64);

2003+ }

2004+ eprintln!(" elements: {}", total_elements);

2005+ eprintln!(" CSS rules: ~{}", total_css_rules);

2006+ if total_errors > 0 {

2007+ eprintln!(" errors: {} file(s) had errors", total_errors);

2008+ }

2009+ if hl_files.len() > 1 {

2010+ let per_file = elapsed.as_secs_f64() * 1000.0 / hl_files.len() as f64;

2011+ eprintln!(" per file: {:.2}ms", per_file);

2012+ }

2013+ return;

2014+ }

2015+

18092016 // Handle "convert" subcommand

18102017 if args.len() >= 2 && args[1] == "convert" {

18112018 if args.len() < 3 {

src/parser.rs+73

@@ -100,6 +100,12 @@ struct ParseContext {

100100 deprecated_fns: HashMap<String, String>,

101101 /// Theme tokens: (name, value) pairs from @theme

102102 theme_tokens: Vec<(String, String)>,

103+ /// Mixin definitions: name -> list of attributes

104+ mixins: HashMap<String, Vec<Attribute>>,

105+ /// Line numbers of @mixin definitions (name -> line)

106+ mixin_lines: HashMap<String, usize>,

107+ /// Track which @mixin definitions are referenced (for unused warnings)

108+ used_mixins: HashSet<String>,

103109 /// Canonical URL

104110 canonical: Option<String>,

105111 /// Base URL for relative links

@@ -154,6 +160,9 @@ pub fn parse_with_base(input: &str, base_path: Option<&Path>) -> ParseResult {

154160 base_url: None,

155161 font_faces: Vec::new(),

156162 json_ld_blocks: Vec::new(),

163+ mixins: HashMap::new(),

164+ mixin_lines: HashMap::new(),

165+ used_mixins: HashSet::new(),

157166 };

158167 let nodes = parser.parse_children(0, &mut ctx);

159168 validate_tree(&nodes, None, &mut ctx.diagnostics);

@@ -478,6 +487,37 @@ impl Parser {

478487 return Ok(None);

479488 }

480489

490+ // --- @mixin directive (composable style groups) ---

491+

492+ if let Some(rest) = content.strip_prefix("@mixin ") {

493+ let rest = rest.trim();

494+ if let Some(bracket_start) = rest.find('[') {

495+ let name = rest[..bracket_start].trim();

496+ let attrs_str = &rest[bracket_start..];

497+ let (attrs, _) = parse_attr_brackets(attrs_str, line_num, ctx)?;

498+ ctx.mixins.insert(name.to_string(), attrs);

499+ ctx.mixin_lines.entry(name.to_string()).or_insert(line_num);

500+ }

501+ return Ok(None);

502+ }

503+

504+ // --- @assert directive (compile-time assertions) ---

505+

506+ if let Some(rest) = content.strip_prefix("@assert ") {

507+ let rest = rest.trim();

508+ let condition = substitute_vars(rest, &ctx.variables);

509+ track_var_refs(rest, &mut ctx.used_variables);

510+ if !evaluate_condition(&condition) {

511+ ctx.diagnostics.push(Diagnostic {

512+ line: line_num,

513+ message: format!("assertion failed: {}", rest),

514+ severity: Severity::Error,

515+ source_line: Some(content.clone()),

516+ });

517+ }

518+ return Ok(None);

519+ }

520+

481521 if let Some(rest) = content.strip_prefix("@include ") {

482522 let filename = substitute_vars(rest.trim(), &ctx.variables);

483523 let resolved = match &ctx.base_path {

@@ -1617,6 +1657,7 @@ const KNOWN_DIRECTIVES: &[&str] = &[

16171657 "unless", "og", "breakpoint", "lang", "favicon",

16181658 "use", "theme", "deprecated", "extends",

16191659 "canonical", "base", "font-face", "json-ld",

1660+ "mixin", "assert",

16201661];

16211662

16221663fn parse_element_kind(s: &str, line_num: usize) -> Result<ElementKind, ParseError> {

@@ -1884,6 +1925,9 @@ fn has_css_unit(value: &str) -> bool {

18841925 CSS_UNIT_SUFFIXES.iter().any(|u| value.ends_with(u))

18851926 || value.starts_with("var(")

18861927 || value.starts_with("calc(")

1928+ || value.starts_with("clamp(")

1929+ || value.starts_with("min(")

1930+ || value.starts_with("max(")

18871931}

18881932

18891933/// Attributes that accept numeric OR keyword values.

@@ -2029,6 +2073,17 @@ fn parse_attr_list(input: &str, line_num: usize, ctx: &mut ParseContext, validat

20292073 continue;

20302074 }

20312075

2076+ // ...$mixin spread — expand mixin attributes

2077+ if part.starts_with("...$") {

2078+ let name = &part[4..];

2079+ if let Some(mixin_attrs) = ctx.mixins.get(name) {

2080+ ctx.used_mixins.insert(name.to_string());

2081+ attrs.extend(mixin_attrs.clone());

2082+ continue;

2083+ }

2084+ // Fall through to try as define

2085+ }

2086+

20322087 // $define reference — expand

20332088 if part.starts_with('$') {

20342089 let name = &part[1..];

@@ -2037,6 +2092,12 @@ fn parse_attr_list(input: &str, line_num: usize, ctx: &mut ParseContext, validat

20372092 attrs.extend(define_attrs.clone());

20382093 continue;

20392094 }

2095+ // Also try mixin expansion with $name syntax

2096+ if let Some(mixin_attrs) = ctx.mixins.get(name) {

2097+ ctx.used_mixins.insert(name.to_string());

2098+ attrs.extend(mixin_attrs.clone());

2099+ continue;

2100+ }

20402101 }

20412102

20422103 // Substitute variables in value

@@ -3044,4 +3105,16 @@ fn check_unused(ctx: &mut ParseContext) {

30443105 });

30453106 }

30463107 }

3108+

3109+ // Check unused @mixin definitions

3110+ for (name, &line) in &ctx.mixin_lines {

3111+ if !ctx.used_mixins.contains(name) {

3112+ ctx.diagnostics.push(Diagnostic {

3113+ line,

3114+ message: format!("unused mixin '{}' (defined but never referenced)", name),

3115+ severity: Severity::Warning,

3116+ source_line: None,

3117+ });

3118+ }

3119+ }

30473120}

tests/snapshots.rs+146

@@ -2884,3 +2884,149 @@ fn no_warning_script_attrs() {

28842884 diags

28852885 );

28862886}

2887+

2888+// ---------------------------------------------------------------------------

2889+// @mixin and spread attributes

2890+// ---------------------------------------------------------------------------

2891+

2892+#[test]

2893+fn snapshot_mixin_spread() {

2894+ snapshot_test("mixin_spread");

2895+}

2896+

2897+#[test]

2898+fn mixin_expands_in_attrs() {

2899+ let output = compile("@mixin card [padding 20, rounded 8]\n@el [...$card]\n Hi");

2900+ assert!(output.contains("padding:20px"), "mixin should expand padding: {}", output);

2901+ assert!(output.contains("border-radius:8px"), "mixin should expand rounded: {}", output);

2902+}

2903+

2904+#[test]

2905+fn mixin_with_dollar_syntax() {

2906+ let output = compile("@mixin card [padding 20, rounded 8]\n@el [$card]\n Hi");

2907+ assert!(output.contains("padding:20px"), "mixin with $ syntax should expand: {}", output);

2908+}

2909+

2910+#[test]

2911+fn mixin_compose_with_extra_attrs() {

2912+ let output = compile("@mixin base [padding 10]\n@el [...$base, background red]\n Hi");

2913+ assert!(output.contains("padding:10px"), "mixin should expand: {}", output);

2914+ assert!(output.contains("background:red"), "extra attrs should work: {}", output);

2915+}

2916+

2917+#[test]

2918+fn warning_unused_mixin() {

2919+ let diags = parse_diagnostics("@mixin card [padding 10]\n@el [background red]");

2920+ assert!(

2921+ diags.iter().any(|d| d.message.contains("unused mixin")),

2922+ "expected unused mixin warning, got: {:?}",

2923+ diags

2924+ );

2925+}

2926+

2927+#[test]

2928+fn no_warning_used_mixin() {

2929+ let diags = parse_diagnostics("@mixin card [padding 10]\n@el [...$card]");

2930+ assert!(

2931+ !diags.iter().any(|d| d.message.contains("unused mixin")),

2932+ "should not warn about used mixin, got: {:?}",

2933+ diags

2934+ );

2935+}

2936+

2937+// ---------------------------------------------------------------------------

2938+// @assert directive

2939+// ---------------------------------------------------------------------------

2940+

2941+#[test]

2942+fn snapshot_assert_directive() {

2943+ snapshot_test("assert_directive");

2944+}

2945+

2946+#[test]

2947+fn assert_passes_no_error() {

2948+ let diags = parse_diagnostics("@let x hello\n@assert $x == hello\n@el [padding 10]");

2949+ assert!(

2950+ !diags.iter().any(|d| d.severity == htmlang::parser::Severity::Error),

2951+ "passing assertion should produce no error, got: {:?}",

2952+ diags

2953+ );

2954+}

2955+

2956+#[test]

2957+fn assert_fails_produces_error() {

2958+ let diags = parse_diagnostics("@let x hello\n@assert $x == world");

2959+ assert!(

2960+ diags.iter().any(|d| d.severity == htmlang::parser::Severity::Error && d.message.contains("assertion failed")),

2961+ "failing assertion should produce error, got: {:?}",

2962+ diags

2963+ );

2964+}

2965+

2966+#[test]

2967+fn assert_not_equal() {

2968+ let diags = parse_diagnostics("@let x hello\n@assert $x != world\n@el");

2969+ assert!(

2970+ !diags.iter().any(|d| d.severity == htmlang::parser::Severity::Error),

2971+ "!= assertion should pass when values differ, got: {:?}",

2972+ diags

2973+ );

2974+}

2975+

2976+#[test]

2977+fn assert_truthy() {

2978+ let diags = parse_diagnostics("@let x true\n@assert $x\n@el");

2979+ assert!(

2980+ !diags.iter().any(|d| d.severity == htmlang::parser::Severity::Error),

2981+ "truthy assertion should pass, got: {:?}",

2982+ diags

2983+ );

2984+}

2985+

2986+// ---------------------------------------------------------------------------

2987+// clamp() / min() / max() CSS functions

2988+// ---------------------------------------------------------------------------

2989+

2990+#[test]

2991+fn snapshot_clamp_css() {

2992+ snapshot_test("clamp_css");

2993+}

2994+

2995+#[test]

2996+fn clamp_passthrough() {

2997+ let output = compile("@el [size clamp(16px, 2vw, 24px)]");

2998+ assert!(output.contains("font-size:clamp(16px, 2vw, 24px)"), "clamp should pass through: {}", output);

2999+}

3000+

3001+#[test]

3002+fn min_passthrough() {

3003+ let output = compile("@el [width min(100%, 800px)]");

3004+ assert!(output.contains("width:min(100%, 800px)"), "min() should pass through: {}", output);

3005+}

3006+

3007+#[test]

3008+fn max_passthrough() {

3009+ let output = compile("@el [padding max(10px, 2vw)]");

3010+ assert!(output.contains("padding:max(10px, 2vw)"), "max() should pass through: {}", output);

3011+}

3012+

3013+// ---------------------------------------------------------------------------

3014+// Round-trip test: parse -> codegen -> convert

3015+// ---------------------------------------------------------------------------

3016+

3017+#[test]

3018+fn round_trip_basic() {

3019+ let input = "@page Round Trip\n@column [padding 20, spacing 10]\n @text [bold, size 24] Hello\n @text World";

3020+ let result = htmlang::parser::parse(input);

3021+ assert!(!result.diagnostics.iter().any(|d| d.severity == htmlang::parser::Severity::Error));

3022+ let html = htmlang::codegen::generate_dev(&result.document);

3023+ // Convert back to .hl

3024+ let hl = htmlang::convert::convert(&html);

3025+ // The round-trip should produce valid .hl that parses without errors

3026+ let result2 = htmlang::parser::parse(&hl);

3027+ assert!(

3028+ !result2.diagnostics.iter().any(|d| d.severity == htmlang::parser::Severity::Error),

3029+ "round-trip should produce valid .hl, got errors: {:?}",

3030+ result2.diagnostics

3031+ );

3032+}

tests/snapshots/assert_directive.hlnew file+10

@@ -0,0 +1,10 @@

1+@page Assert Test

3+@let spacing 16

4+@let primary #3b82f6

6+@assert $spacing == 16

7+@assert $primary != red

9+@el [padding $spacing, color $primary]

10+ Assertions passed

tests/snapshots/clamp_css.hlnew file+4

@@ -0,0 +1,4 @@

1+@page Clamp CSS Test

3+@el [size clamp(16px, 2vw, 24px), width min(100%, 800px), padding max(10px, 2vw)]

4+ Fluid typography and sizing

tests/snapshots/mixin_spread.hlnew file+10

@@ -0,0 +1,10 @@

1+@page Mixin Test

3+@mixin card-style [padding 20, rounded 8, background #f3f4f6]

4+@mixin interactive [cursor pointer, hover:background #e5e7eb, transition all 0.15s ease]

6+@el [...$card-style, ...$interactive]

7+ Hello mixin world

9+@el [$card-style, border 1 #ccc]

10+ Using $define syntax too