Improve error messages (#980)

swc_ecma_parser:
 - Improve error messages

ecmascript/parser/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "swc_ecma_parser"
-version = "0.34.0"
+version = "0.34.1"
 authors = ["강동윤 <kdy1997.dev@gmail.com>"]
 license = "Apache-2.0/MIT"
 repository = "https://github.com/swc-project/swc.git"

ecmascript/parser/src/error.rs

@@ -1,6 +1,5 @@
 #![allow(dead_code)]
 
-use self::SyntaxError::*;
 use crate::token::Token;
 use std::{borrow::Cow, fmt::Debug};
 use swc_atoms::JsWord;
@@ -31,6 +30,15 @@ impl Error {
 #[non_exhaustive]
 pub enum SyntaxError {
     Eof,
+    DeclNotAllowed,
+
+    InvalidSuperCall,
+    InvalidSuper,
+
+    ArrowNotAllowed,
+    ExportNotAllowed,
+    GetterSetterCannotBeReadonly,
+
     TopLevelAwait,
 
     LegacyDecimal,
@@ -79,6 +87,7 @@ pub enum SyntaxError {
     /// Unexpected token
     Unexpected {
         got: String,
+        expected: &'static str,
     },
     ReservedWordInImport,
     AssignProperty,
@@ -141,6 +150,7 @@ pub enum SyntaxError {
     DeclarePrivateIdentifier,
     ClassProperty,
     ReadOnlyMethod,
+    GeneratorConstructor,
     TsBindingPatCannotBeOptional,
 
     TrailingCommaInsideImport,
@@ -203,20 +213,22 @@ pub enum SyntaxError {
     TS2703,
 }
 
-impl Error {
+impl SyntaxError {
     #[cold]
-    pub fn into_diagnostic(self, handler: &Handler) -> DiagnosticBuilder {
+    #[inline(never)]
-        let span = self.span();
+    pub fn msg(&self) -> Cow<'static, str> {
-
+        match self {
-        let kind = self.kind();
+            SyntaxError::TopLevelAwait => "top level await requires target to es2017 or higher \
-        let msg: Cow<'static, _> = match kind {
+                                           and topLevelAwait:true for ecmascript"
-            TopLevelAwait => "top level await requires target to es2017 or higher and \
-                              topLevelAwait:true for ecmascript"
                 .into(),
-            LegacyDecimal => "Legacy decimal escape is not permitted in strict mode".into(),
+            SyntaxError::LegacyDecimal => {
-            LegacyOctal => "Legacy octal escape is not permitted in strict mode".into(),
+                "Legacy decimal escape is not permitted in strict mode".into()
-            InvalidIdentChar => "Invalid character in identifier".into(),
+            }
-            ExpectedDigit { radix } => format!(
+            SyntaxError::LegacyOctal => {
+                "Legacy octal escape is not permitted in strict mode".into()
+            }
+            SyntaxError::InvalidIdentChar => "Invalid character in identifier".into(),
+            SyntaxError::ExpectedDigit { radix } => format!(
                 "Expected {} digit",
                 match radix {
                     2 => "a binary",
@@ -227,159 +239,304 @@ impl Error {
                 }
             )
             .into(),
-            UnterminatedBlockComment => "Unterminated block comment".into(),
+            SyntaxError::UnterminatedBlockComment => "Unterminated block comment".into(),
-            UnterminatedStrLit => "Unterminated string constant".into(),
+            SyntaxError::UnterminatedStrLit => "Unterminated string constant".into(),
-            ExpectedUnicodeEscape => "Expected unicode escape".into(),
+            SyntaxError::ExpectedUnicodeEscape => "Expected unicode escape".into(),
-            EscapeInReservedWord { ref word } => {
+            SyntaxError::EscapeInReservedWord { ref word } => {
                 format!("Unexpected escape sequence in reserved word: {}", word).into()
             }
-            UnterminatedRegxp => "Unterminated regexp literal".into(),
+            SyntaxError::UnterminatedRegxp => "Unterminated regexp literal".into(),
-            UnterminatedTpl => "Unterminated template".into(),
+            SyntaxError::UnterminatedTpl => "Unterminated template".into(),
-            IdentAfterNum => "Identifier cannot follow number".into(),
+            SyntaxError::IdentAfterNum => "Identifier cannot follow number".into(),
-            UnexpectedChar { c } => format!("Unexpected character {:?}", c).into(),
+            SyntaxError::UnexpectedChar { c } => format!("Unexpected character {:?}", c).into(),
-            InvalidStrEscape => "Invalid string escape".into(),
+            SyntaxError::InvalidStrEscape => "Invalid string escape".into(),
-            InvalidUnicodeEscape => "Invalid unciode escape".into(),
+            SyntaxError::InvalidUnicodeEscape => "Invalid unciode escape".into(),
-            InvalidCodePoint => "Invalid unciode code point".into(),
+            SyntaxError::InvalidCodePoint => "Invalid unciode code point".into(),
-            ExpectedHexChars { count } => format!("Expected {} hex characters", count).into(),
+            SyntaxError::ExpectedHexChars { count } => {
-            LegacyCommentInModule => "Legacy comments cannot be used in module code".into(),
+                format!("Expected {} hex characters", count).into()
-            NumLitTerminatedWithExp => "Expected +, - or decimal digit after e".into(),
+            }
+            SyntaxError::LegacyCommentInModule => {
+                "Legacy comments cannot be used in module code".into()
+            }
+            SyntaxError::NumLitTerminatedWithExp => "Expected +, - or decimal digit after e".into(),
 
-            InvalidIdentInStrict => "'implements', 'interface', 'let', 'package', 'private', \
+            SyntaxError::InvalidIdentInStrict => {
-                                     'protected',  'public', 'static', or 'yield' cannot be used \
+                "'implements', 'interface', 'let', 'package', 'private', 'protected',  'public', \
-                                     as an identifier in strict mode"
+                 'static', or 'yield' cannot be used as an identifier in strict mode"
+                    .into()
+            }
+            SyntaxError::EvalAndArgumentsInStrict => "'eval' and 'arguments' cannot be used as a \
+                                                      binding identifier in strict mode"
                 .into(),
-            EvalAndArgumentsInStrict => "'eval' and 'arguments' cannot be used as a binding \
+            SyntaxError::UnaryInExp { .. } => "** cannot be applied to unary expression".into(),
-                                         identifier in strict mode"
+            SyntaxError::Hash => "Unexpected token '#'".into(),
-                .into(),
+            SyntaxError::LineBreakInThrow => "LineBreak cannot follow 'throw'".into(),
-            UnaryInExp { .. } => "** cannot be applied to unary expression".into(),
+            SyntaxError::LineBreakBeforeArrow => {
-            Hash => "Unexpected token '#'".into(),
+                "Unexpected line break between arrow head and arrow".into()
-            LineBreakInThrow => "LineBreak cannot follow 'throw'".into(),
+            }
-            LineBreakBeforeArrow => "Unexpected line break between arrow head and arrow".into(),
+            SyntaxError::Unexpected {
-            Unexpected { ref got } => format!("Unexpected token {}", got).into(),
+                ref got,
+                ref expected,
+            } => format!("Unexpected token `{}`. Expected {}", got, expected).into(),
 
-            ReservedWordInImport => "cannot import as reserved word".into(),
+            SyntaxError::ReservedWordInImport => "cannot import as reserved word".into(),
-            AssignProperty => "assignment property is invalid syntax".into(),
+            SyntaxError::AssignProperty => "assignment property is invalid syntax".into(),
-            Expected(token, ref got) => format!("Expected {:?}, got {}", token, got).into(),
+            SyntaxError::Expected(token, ref got) => {
-            ExpectedSemiForExprStmt { .. } => "Expected ';', '}' or <eof>".into(),
+                format!("Expected {:?}, got {}", token, got).into()
+            }
+            SyntaxError::ExpectedSemiForExprStmt { .. } => "Expected ';', '}' or <eof>".into(),
 
-            AwaitStar => "await* has been removed from the async functions proposal. Use \
+            SyntaxError::AwaitStar => "await* has been removed from the async functions proposal. \
-                          Promise.all() instead."
+                                       Use Promise.all() instead."
                 .into(),
 
-            ReservedWordInObjShorthandOrPat => {
+            SyntaxError::ReservedWordInObjShorthandOrPat => {
                 "Cannot use a reserved word as a shorthand property".into()
             }
 
-            MultipleDefault { .. } => "A switch block cannot have multiple defaults".into(),
+            SyntaxError::MultipleDefault { .. } => {
-            CommaAfterRestElement => "Trailing comma isn't permitted after a rest element".into(),
+                "A switch block cannot have multiple defaults".into()
-            NonLastRestParam => "Rest element must be final element".into(),
+            }
-            SpreadInParenExpr => "Parenthesized expression cannot contain spread operator".into(),
+            SyntaxError::CommaAfterRestElement => {
-            EmptyParenExpr => "Parenthized expression cannot be empty".into(),
+                "Trailing comma isn't permitted after a rest element".into()
-            InvalidPat => "Not a pattern".into(),
+            }
-            InvalidExpr => "Not an expression".into(),
+            SyntaxError::NonLastRestParam => "Rest element must be final element".into(),
+            SyntaxError::SpreadInParenExpr => {
+                "Parenthesized expression cannot contain spread operator".into()
+            }
+            SyntaxError::EmptyParenExpr => "Parenthized expression cannot be empty".into(),
+            SyntaxError::InvalidPat => "Not a pattern".into(),
+            SyntaxError::InvalidExpr => "Not an expression".into(),
             // TODO
-            NotSimpleAssign => "Cannot assign to this".into(),
+            SyntaxError::NotSimpleAssign => "Cannot assign to this".into(),
-            ExpectedIdent => "Expected ident".into(),
+            SyntaxError::ExpectedIdent => "Expected ident".into(),
-            ExpctedSemi => "Expected ';' or line break".into(),
+            SyntaxError::ExpctedSemi => "Expected ';' or line break".into(),
-            DuplicateLabel(ref label) => format!("Label {} is already declared", label).into(),
+            SyntaxError::DuplicateLabel(ref label) => {
-            AsyncGenerator => "An async function cannot be generator".into(),
+                format!("Label {} is already declared", label).into()
-            NonTopLevelImportExport => "'import', and 'export' are not permitted here".into(),
+            }
-            ImportExportInScript => {
+            SyntaxError::AsyncGenerator => "An async function cannot be generator".into(),
+            SyntaxError::NonTopLevelImportExport => {
+                "'import', and 'export' are not permitted here".into()
+            }
+            SyntaxError::ImportExportInScript => {
                 "'import', and 'export' cannot be used outside of module code".into()
             }
 
-            PatVarWithoutInit => "Destructuring bindings require initializers".into(),
+            SyntaxError::PatVarWithoutInit => "Destructuring bindings require initializers".into(),
-            WithInStrict => "With statement are not allowed in strict mode".into(),
+            SyntaxError::WithInStrict => "With statement are not allowed in strict mode".into(),
-            ReturnNotAllowed => "Return statement is not allowed here".into(),
+            SyntaxError::ReturnNotAllowed => "Return statement is not allowed here".into(),
-            TooManyVarInForInHead => "Expected one variable binding".into(),
+            SyntaxError::TooManyVarInForInHead => "Expected one variable binding".into(),
-            VarInitializerInForInHead => "Unexpected initializer in for in/of loop".into(),
+            SyntaxError::VarInitializerInForInHead => {
-            LabelledGenerator => "Generator cannot be labelled".into(),
+                "Unexpected initializer in for in/of loop".into()
-            YieldParamInGen => "'yield' cannot be used as a parameter within generator".into(),
+            }
-            AwaitForStmt => "for await syntax is valid only for for-of statement".into(),
+            SyntaxError::LabelledGenerator => "Generator cannot be labelled".into(),
+            SyntaxError::YieldParamInGen => {
+                "'yield' cannot be used as a parameter within generator".into()
+            }
+            SyntaxError::AwaitForStmt => {
+                "for await syntax is valid only for for-of statement".into()
+            }
 
-            UnterminatedJSXContents => "Unterminated JSX contents".into(),
+            SyntaxError::UnterminatedJSXContents => "Unterminated JSX contents".into(),
-            EmptyJSXAttr => "JSX attributes must only be assigned a non-empty expression".into(),
+            SyntaxError::EmptyJSXAttr => {
-            InvalidJSXValue => {
+                "JSX attributes must only be assigned a non-empty expression".into()
+            }
+            SyntaxError::InvalidJSXValue => {
                 "JSX value should be either an expression or a quoted JSX text".into()
             }
-            JSXExpectedClosingTagForLtGt => "Expected corresponding JSX closing tag for <>".into(),
+            SyntaxError::JSXExpectedClosingTagForLtGt => {
-            JSXExpectedClosingTag { ref tag } => {
+                "Expected corresponding JSX closing tag for <>".into()
+            }
+            SyntaxError::JSXExpectedClosingTag { ref tag } => {
                 format!("Expected corresponding JSX closing tag for <{}>", tag).into()
             }
-            InvalidLeadingDecorator => {
+            SyntaxError::InvalidLeadingDecorator => {
                 "Leading decorators must be attached to a class declaration".into()
             }
-            DecoratorOnExport => "Using the export keyword between a decorator and a class is not \
+            SyntaxError::DecoratorOnExport => "Using the export keyword between a decorator and a \
-                                  allowed. Please use `export @dec class` instead."
+                                               class is not allowed. Please use `export @dec \
+                                               class` instead."
                 .into(),
-            TsRequiredAfterOptional => {
+            SyntaxError::TsRequiredAfterOptional => {
                 "A required element cannot follow an optional element.".into()
             }
-            TsInvalidParamPropPat => {
+            SyntaxError::TsInvalidParamPropPat => {
                 "Typescript parameter property must be identifer or assignment pattern".into()
             }
-            SpaceBetweenHashAndIdent => "Unexpected space between # and identifier".into(),
+            SyntaxError::SpaceBetweenHashAndIdent => {
-            AsyncConstructor => "Constructor can't be an async function".into(),
+                "Unexpected space between # and identifier".into()
-            PropertyNamedConstructor => {
+            }
+            SyntaxError::AsyncConstructor => "Constructor can't be an async function".into(),
+            SyntaxError::PropertyNamedConstructor => {
                 "Classes may not have a non-static field named 'constructor'".into()
             }
-            DeclarePrivateIdentifier => {
+            SyntaxError::DeclarePrivateIdentifier => {
                 "'declare' modifier cannot be used with a private identifier".into()
             }
-            ClassProperty => "Class property requires `jsc.parser.classProperty` to be true".into(),
+            SyntaxError::ClassProperty => {
-            ReadOnlyMethod => "A method cannot be readonly".into(),
+                "Class property requires `jsc.parser.classProperty` to be true".into()
-            TsBindingPatCannotBeOptional => "A binding pattern parameter cannot be optional in an \
+            }
-                                             implementation signature."
+            SyntaxError::ReadOnlyMethod => "A method cannot be readonly".into(),
+            SyntaxError::TsBindingPatCannotBeOptional => "A binding pattern parameter cannot be \
+                                                          optional in an implementation signature."
                 .into(),
 
-            TrailingCommaInsideImport => {
+            SyntaxError::TrailingCommaInsideImport => {
                 "Trailing comma is disallowed inside import(...) arguments".into()
             }
-            DynamicImport => {
+            SyntaxError::DynamicImport => {
                 "import(...) expressions requires `jsc.parser.dynamicImport` to be true".into()
             }
-            ExportDefaultWithOutFrom => "export default statements required from '...';".into(),
+            SyntaxError::ExportDefaultWithOutFrom => {
-            ExportNamespaceFrom => "export * as Foo from 'foo'; requires \
+                "export default statements required from '...';".into()
+            }
+            SyntaxError::ExportNamespaceFrom => "export * as Foo from 'foo'; requires \
                                                  `jsc.parser.exportNamespaceFrom` to be true"
                 .into(),
 
-            DotsWithoutIdentifier => {
+            SyntaxError::DotsWithoutIdentifier => {
                 "`...` must be followed by an identifier in declaration contexts".into()
             }
 
-            NumericSeparatorIsAllowedOnlyBetweenTwoDigits => {
+            SyntaxError::NumericSeparatorIsAllowedOnlyBetweenTwoDigits => {
                 "A numeric separator is only allowed between two digits".into()
             }
 
-            NullishCoalescingWithLogicalOp => "Nullish coalescing operator(??) requires parens \
+            SyntaxError::NullishCoalescingWithLogicalOp => {
-                                               when mixing with logical operators"
+                "Nullish coalescing operator(??) requires parens when mixing with logical operators"
-                .into(),
+                    .into()
-            NullishCoalescingNotEnabled => {
+            }
+            SyntaxError::NullishCoalescingNotEnabled => {
                 "Nullish coalescing operator(??) requires jsc.parser.nullishCoalescing".into()
             }
 
-            TS1056 => "jsc.taraget should be es5 or upper to use getter / setter".into(),
+            SyntaxError::TS1056 => {
-            TS1110 => "type expected".into(),
+                "jsc.taraget should be es5 or upper to use getter / setter".into()
-            TS1141 => "literal in an import type should be string literal".into(),
+            }
+            SyntaxError::TS1110 => "type expected".into(),
+            SyntaxError::TS1141 => "literal in an import type should be string literal".into(),
 
-            Eof => "Unexpected eof".into(),
+            SyntaxError::Eof => "Unexpected eof".into(),
 
-            TS2703 => "The operand of a delete operator must be a property reference.".into(),
+            SyntaxError::TS2703 => {
-            // TODO:
+                "The operand of a delete operator must be a property reference.".into()
-            _ => format!("{:?}", kind).into(),
+            }
-        };
+            SyntaxError::DeclNotAllowed => "Declatation is now allowed".into(),
+            SyntaxError::InvalidSuperCall => "Invalid `super()`".into(),
+            SyntaxError::InvalidSuper => "Invalid access to super".into(),
+            SyntaxError::ArrowNotAllowed => "An arrow function is not allowed here".into(),
+            SyntaxError::ExportNotAllowed => "`export` is not aloowed here".into(),
+            SyntaxError::GetterSetterCannotBeReadonly => {
+                "A getter or a setter cannot be readonly".into()
+            }
+            SyntaxError::RestPatInSetter => "Rest pattern is not allowed in setter".into(),
+
+            SyntaxError::GeneratorConstructor => "A constructor cannot be generator".into(),
+
+            SyntaxError::TS1003 => "Expected an identifier".into(),
+            SyntaxError::TS1005 => "Expected a semicolon".into(),
+            SyntaxError::TS1009 => "Trailing comma is not allowed".into(),
+            SyntaxError::TS1014 => "A rest parameter must be last in a parameter list".into(),
+            SyntaxError::TS1015 => "Parameter cannot have question mark and initializer".into(),
+            SyntaxError::TS1031 => "`declare` modifier cannot appear on a class element".into(),
+            SyntaxError::TS1038 => {
+                "`declare` modifier not allowed for code already in an ambient context".into()
+            }
+            SyntaxError::TS1042 => "`async` modifier cannot be used here".into(),
+            SyntaxError::TS1047 => "A rest parameter cannot be optional".into(),
+            SyntaxError::TS1048 => "A rest parameter cannot have an initializer".into(),
+            SyntaxError::TS1085 => "Legacy octal literals are not available when targeting \
+                                    ECMAScript 5 and higher"
+                .into(),
+            SyntaxError::TS1089 => {
+                "'private' modifier cannot appear on a constructor declaration".into()
+            }
+            SyntaxError::TS1092 => {
+                "Type parameters cannot appear on a constructor declaration".into()
+            }
+            SyntaxError::TS1096 => "An index signature must have exactly one parameter".into(),
+            SyntaxError::TS1098 => "Type parameter list cannot be empty".into(),
+            SyntaxError::TS1100 => "Invalid use of 'arguments' in strict mode".into(),
+            SyntaxError::TS1102 => {
+                "'delete' cannot be called on an identifier in strict mode".into()
+            }
+            SyntaxError::TS1105 => "A 'break' statement can only be used within an enclosing \
+                                    iteration or switch statement"
+                .into(),
+            SyntaxError::TS1107 => "Jump target cannot cross function boundary".into(),
+            SyntaxError::TS1109 => "Expression expected".into(),
+            SyntaxError::TS1114 => "Duplicate label".into(),
+            SyntaxError::TS1115 => "A 'continue' statement can only jump to a label of an \
+                                    enclosing iteration statement"
+                .into(),
+            SyntaxError::TS1116 => {
+                "A 'break' statement can only jump to a label of an enclosing statement".into()
+            }
+            SyntaxError::TS1123 => "Variable declaration list cannot be empty".into(),
+            SyntaxError::TS1162 => "An object member cannot be declared optional".into(),
+            SyntaxError::TS1164 => "Computed property names are not allowed in enums".into(),
+            SyntaxError::TS1171 => {
+                "A comma expression is not allowed in a computed property name".into()
+            }
+            SyntaxError::TS1172 => "`extends` clause already seen.".into(),
+            SyntaxError::TS1174 => "Classes can only extend a single class".into(),
+            SyntaxError::TS1175 => "`implements` clause already seen".into(),
+            SyntaxError::TS1183 => {
+                "An implementation cannot be declared in ambient contexts".into()
+            }
+            SyntaxError::TS1093 => {
+                "Type annotation cannot appear on a constructor declaration".into()
+            }
+            SyntaxError::TS1094 => {
+                "A `set` accessor must have a corresponding `get` accessor".into()
+            }
+            SyntaxError::TS1196 => "Catch clause variable cannot have a type annotation".into(),
+            SyntaxError::TS1242 => {
+                "`abstract` modifier can only appear on a class or method declaration".into()
+            }
+            SyntaxError::TS2369 => {
+                "A parameter property is only allowed in a constructor implementation".into()
+            }
+            SyntaxError::TS2371 => "A parameter initializer is only allowed in a function or \
+                                    constructor implementation"
+                .into(),
+            SyntaxError::TS2406 => "Invalid left-hand side in 'for...in' statement".into(),
+            SyntaxError::TS2410 => "The 'with' statement is not supported. All symbols in a \
+                                    'with' block will have type 'any'."
+                .into(),
+            SyntaxError::TS2414 => "Invalid class name".into(),
+            SyntaxError::TS2427 => "interface name is invalid".into(),
+            SyntaxError::TS2452 => "An enum member cannot have a numeric name".into(),
+            SyntaxError::TS2483 => {
+                "The left-hand side of a 'for...of' statement cannot use a type annotation".into()
+            }
+            SyntaxError::TS2491 => "The left-hand side of a 'for...in' statement cannot be a \
+                                    destructuring pattern"
+                .into(),
+        }
+    }
+}
+
+impl Error {
+    #[cold]
+    #[inline(never)]
+    pub fn into_diagnostic(self, handler: &Handler) -> DiagnosticBuilder {
+        let span = self.span();
+
+        let kind = self.kind();
+        let msg = kind.msg();
 
         let mut db = handler.struct_err(&msg);
         db.set_span(span);
 
         match kind {
-            ExpectedSemiForExprStmt { expr } => {
+            SyntaxError::ExpectedSemiForExprStmt { expr } => {
                 db.span_note(
                     expr,
                     "This is the expression part of an expression statement",
                 );
             }
-            MultipleDefault { previous } => {
+            SyntaxError::MultipleDefault { previous } => {
                 db.span_note(previous, "previous default case is declared at here");
             }
             _ => {}

ecmascript/parser/src/parser/class_and_fn.rs

@@ -198,7 +198,7 @@ impl<'a, I: Tokens> Parser<I> {
 
         if is!("export") {
             if !allow_export {
-                unexpected!();
+                syntax_error!(self.input.cur_span(), SyntaxError::ExportNotAllowed);
             }
 
             if !self.syntax().decorators_before_export() {
@@ -454,11 +454,12 @@ impl<'a, I: Tokens> Parser<I> {
             // generator method
             let key = self.parse_class_prop_name()?;
             if readonly {
-                syntax_error!(span!(start), SyntaxError::ReadOnlyMethod);
+                self.emit_err(span!(start), SyntaxError::ReadOnlyMethod);
             }
             if is_constructor(&key) {
-                unexpected!();
+                self.emit_err(span!(start), SyntaxError::GeneratorConstructor);
             }
+
             return self.make_method(
                 |p| p.parse_unique_formal_params(),
                 MakeMethodArgs {
@@ -656,7 +657,7 @@ impl<'a, I: Tokens> Parser<I> {
                 let key = self.parse_class_prop_name()?;
 
                 if readonly {
-                    unexpected!()
+                    self.emit_err(key_span, SyntaxError::GetterSetterCannotBeReadonly);
                 }
 
                 return match i.sym {
@@ -718,7 +719,7 @@ impl<'a, I: Tokens> Parser<I> {
             _ => {}
         }
 
-        unexpected!()
+        unexpected!("* for generator, private key, identifier or async")
     }
 
     fn make_property(

ecmascript/parser/src/parser/expr.rs

@@ -81,7 +81,7 @@ impl<'a, I: Tokens> Parser<I> {
                     }) => {
                         *type_params = Some(type_parameters);
                     }
-                    _ => unexpected!(),
+                    _ => unexpected!("("),
                 }
                 Ok(Some(arrow))
             });
@@ -374,7 +374,11 @@ impl<'a, I: Tokens> Parser<I> {
             }
         }
 
-        unexpected!()
+        unexpected!(
+            "this, import, async, function, [ for array literal, { for object literal, @ for \
+             decorator, function, class, null, true, false, number, bigint, string, regexp, ` for \
+             template literal, (, or an identifier"
+        )
     }
 
     fn parse_array_lit(&mut self) -> PResult<Box<Expr>> {
@@ -422,7 +426,7 @@ impl<'a, I: Tokens> Parser<I> {
         let prop = if is!("meta") {
             self.parse_ident_name()?
         } else {
-            unexpected!();
+            unexpected!("meta");
         };
 
         Ok(MetaPropExpr { meta, prop })
@@ -446,7 +450,7 @@ impl<'a, I: Tokens> Parser<I> {
                     return self.parse_subscripts(ExprOrSuper::Expr(expr), true);
                 }
 
-                unexpected!()
+                unexpected!("target")
             }
 
             // 'NewExpression' allows new call without paren.
@@ -457,7 +461,8 @@ impl<'a, I: Tokens> Parser<I> {
                 self.try_parse_ts(|p| {
                     let args = p.parse_ts_type_args()?;
                     if !is!('(') {
-                        unexpected!()
+                        // This will fail
+                        expect!('(');
                     }
                     Ok(Some(args))
                 })
@@ -626,7 +631,7 @@ impl<'a, I: Tokens> Parser<I> {
                 syntax_error!(span!(expr_start), SyntaxError::LineBreakBeforeArrow);
             }
             if !can_be_arrow {
-                unexpected!()
+                syntax_error!(span!(expr_start), SyntaxError::ArrowNotAllowed);
             }
             expect!("=>");
 
@@ -834,7 +839,7 @@ impl<'a, I: Tokens> Parser<I> {
                 ),
                 _ => unreachable!(),
             },
-            _ => unexpected!(),
+            _ => unexpected!("template token"),
         };
         let tail = is!('`');
         Ok(TplElement {
@@ -934,7 +939,11 @@ impl<'a, I: Tokens> Parser<I> {
                         .map(|expr| (Box::new(Expr::TaggedTpl(expr)), true))
                         .map(Some)
                     } else {
-                        unexpected!()
+                        if no_call {
+                            unexpected!("`")
+                        } else {
+                            unexpected!("( or `")
+                        }
                     }
                 });
                 if let Some(result) = result {
@@ -1037,9 +1046,9 @@ impl<'a, I: Tokens> Parser<I> {
             }
             ExprOrSuper::Super(..) => {
                 if no_call {
-                    unexpected!()
+                    syntax_error!(self.input.cur_span(), SyntaxError::InvalidSuperCall);
                 }
-                unexpected!()
+                syntax_error!(self.input.cur_span(), SyntaxError::InvalidSuper);
             }
         }
     }

ecmascript/parser/src/parser/jsx.rs

@@ -21,7 +21,7 @@ impl<'a, I: Tokens> Parser<I> {
                 _ => unreachable!(),
             },
             _ if ctx.in_forced_jsx_context => self.parse_ident_ref(),
-            _ => unexpected!(),
+            _ => unexpected!("jsx identifier"),
         }
     }
 
@@ -216,7 +216,7 @@ impl<'a, I: Tokens> Parser<I> {
         }
         let self_closing = eat!('/');
         if !eat!(JSXTagEnd) & !(self.ctx().in_forced_jsx_context && eat!('>')) {
-            unexpected!()
+            unexpected!("> (jsx closing tag)");
         }
         Ok(JSXOpeningElement {
             span: span!(start),
@@ -314,7 +314,7 @@ impl<'a, I: Tokens> Parser<I> {
                                 );
                             }
                         }
-                        _ => unexpected!(),
+                        _ => unexpected!("< (jsx tag start), jsx text or {"),
                     }
                 }
             }

ecmascript/parser/src/parser/macros.rs

@@ -1,7 +1,17 @@
 macro_rules! unexpected {
-    ($p:expr) => {{
+    ($p:expr, $expected:literal) => {{
-        let got = format!("{:?}", cur!($p, false).ok());
+        let got = match cur!($p, false).ok() {
-        syntax_error!($p, $p.input.cur_span(), SyntaxError::Unexpected { got })
+            Some(v) => format!("{:?}", v),
+            None => format!("<eof>"),
+        };
+        syntax_error!(
+            $p,
+            $p.input.cur_span(),
+            SyntaxError::Unexpected {
+                got,
+                expected: $expected
+            }
+        )
     }};
 }
 

ecmascript/parser/src/parser/mod.rs

@@ -153,6 +153,8 @@ impl<I: Tokens> Parser<I> {
         self.input.get_ctx()
     }
 
+    #[cold]
+    #[inline(never)]
     fn emit_err(&self, span: Span, error: SyntaxError) {
         if !self.emit_err || !self.syntax().early_errors() {
             return;
@@ -163,6 +165,8 @@ impl<I: Tokens> Parser<I> {
         })
     }
 
+    #[cold]
+    #[inline(never)]
     fn emit_error(&self, error: Error) {
         if !self.emit_err || !self.syntax().early_errors() {
             return;

ecmascript/parser/src/parser/object.rs

@@ -97,7 +97,9 @@ impl<'a, I: Tokens> Parser<I> {
                         expr,
                     })
                 }
-                _ => unexpected!(),
+                _ => unexpected!(
+                    "identifier, string literal, numeric literal or [ for the computed key"
+                ),
             };
 
             Ok(v)
@@ -198,7 +200,8 @@ impl<I: Tokens> ParseObject<Box<Expr>> for Parser<I> {
 
         let ident = match key {
             PropName::Ident(ident) => ident,
-            _ => unexpected!(),
+            // TODO
+            _ => unexpected!("identifier"),
         };
 
         if eat!('?') {
@@ -347,7 +350,16 @@ impl<I: Tokens> ParseObject<Box<Expr>> for Parser<I> {
                     _ => unreachable!(),
                 }
             }
-            _ => unexpected!(),
+            _ => {
+                if self.input.syntax().typescript() {
+                    unexpected!(
+                        "... , *,  (, [, :, , ?, =, an identifier, public, protected, private, \
+                         readonly, <."
+                    )
+                } else {
+                    unexpected!("... , *,  (, [, :, , ?, = or an identifier")
+                }
+            }
         }
     }
 }
@@ -412,7 +424,7 @@ impl<I: Tokens> ParseObject<Pat> for Parser<I> {
         }
         let key = match key {
             PropName::Ident(ident) => ident,
-            _ => unexpected!(),
+            _ => unexpected!("an identifier"),
         };
 
         let value = if eat!('=') {

ecmascript/parser/src/parser/pat.rs

@@ -51,7 +51,7 @@ impl<'a, I: Tokens> Parser<I> {
             //     expect!(')');
             //     Ok(pat)
             // }
-            _ => unexpected!(),
+            _ => unexpected!("yield, an identifier, [ or {"),
         }
     }
 

ecmascript/parser/src/parser/stmt.rs

@@ -172,7 +172,7 @@ impl<'a, I: Tokens> Parser<I> {
 
         if is!("function") {
             if !include_decl {
-                unexpected!()
+                self.emit_err(self.input.cur_span(), SyntaxError::DeclNotAllowed);
             }
 
             return self.parse_fn_decl(decorators).map(Stmt::from);
@@ -180,7 +180,7 @@ impl<'a, I: Tokens> Parser<I> {
 
         if is!("class") {
             if !include_decl {
-                unexpected!()
+                self.emit_err(self.input.cur_span(), SyntaxError::DeclNotAllowed);
             }
             return self
                 .parse_class_decl(start, start, decorators)

ecmascript/parser/src/parser/stmt/module_item.rs

@@ -148,7 +148,7 @@ impl<'a, I: Tokens> Parser<I> {
                     imported: None,
                 }))
             }
-            _ => unexpected!(),
+            _ => unexpected!("an identifier"),
         }
     }
 
@@ -503,7 +503,7 @@ impl<'a, I: Tokens> Parser<I> {
                 },
                 _ => unreachable!(),
             },
-            _ => unexpected!(),
+            _ => unexpected!("a string literal"),
         };
         expect!(';');
         Ok(src)

ecmascript/parser/src/parser/typescript.rs

@@ -376,7 +376,7 @@ impl<I: Tokens> Parser<I> {
         let start = cur_pos!();
 
         if !is!('<') && !is!(JSXTagStart) {
-            unexpected!()
+            unexpected!("< (jsx tag start)")
         }
         bump!(); // '<'
 
@@ -534,12 +534,23 @@ impl<I: Tokens> Parser<I> {
     }
 
     /// `tsExpectThenParseType`
-    fn expect_then_parse_ts_type(&mut self, token: &'static Token) -> PResult<Box<TsType>> {
+    fn expect_then_parse_ts_type(
+        &mut self,
+        token: &'static Token,
+        token_str: &'static str,
+    ) -> PResult<Box<TsType>> {
         debug_assert!(self.input.syntax().typescript());
 
         self.in_type().parse_with(|p| {
             if !p.input.eat(token) {
-                unexpected!()
+                let got = format!("{:?}", cur!(false).ok());
+                syntax_error!(
+                    p.input.cur_span(),
+                    SyntaxError::Unexpected {
+                        got,
+                        expected: token_str
+                    }
+                );
             }
 
             p.parse_ts_type()
@@ -711,7 +722,7 @@ impl<I: Tokens> Parser<I> {
             })?;
             (false, id)
         } else {
-            unexpected!();
+            unexpected!("global or a string literal");
         };
 
         let body = if is!('{') {
@@ -919,7 +930,7 @@ impl<I: Tokens> Parser<I> {
 
         let id = self.parse_ident_name()?;
         let type_params = self.try_parse_ts_type_params()?;
-        let type_ann = self.expect_then_parse_ts_type(&tok!('='))?;
+        let type_ann = self.expect_then_parse_ts_type(&tok!('='), "=")?;
         expect!(';');
         Ok(TsTypeAliasDecl {
             declare: false,
@@ -981,7 +992,7 @@ impl<I: Tokens> Parser<I> {
         expect!('(');
         match *cur!(true)? {
             Token::Str { .. } => {}
-            _ => unexpected!(),
+            _ => unexpected!("a string literal"),
         }
         let expr = match self.parse_lit()? {
             Lit::Str(s) => s,
@@ -1362,7 +1373,7 @@ impl<I: Tokens> Parser<I> {
 
         let start = cur_pos!();
         let name = self.parse_ident_name()?;
-        let constraint = Some(self.expect_then_parse_ts_type(&tok!("in"))?);
+        let constraint = Some(self.expect_then_parse_ts_type(&tok!("in"), "in")?);
 
         Ok(TsTypeParam {
             span: span!(start),
@@ -1601,7 +1612,10 @@ impl<I: Tokens> Parser<I> {
                 Pat::Array(pat) => TsFnParam::Array(pat),
                 Pat::Object(pat) => TsFnParam::Object(pat),
                 Pat::Rest(pat) => TsFnParam::Rest(pat),
-                _ => unexpected!(),
+                _ => unexpected!(
+                    "an identifier, [ for an array pattern, { for an object patter or ... for a \
+                     rest pattern"
+                ),
             };
             list.push(item);
         }
@@ -1723,7 +1737,7 @@ impl<I: Tokens> Parser<I> {
                     Token::Num(..) => false,
                     _ => true,
                 } {
-                    unexpected!()
+                    unexpected!("a numeric literal")
                 }
                 let lit = self.parse_lit()?;
                 let lit = match lit {
@@ -1781,7 +1795,10 @@ impl<I: Tokens> Parser<I> {
         //   switch (self.state.type) {
         //   }
 
-        unexpected!()
+        unexpected!(
+            "an identifier, void, yield, null, await, break, a string literal, a numeric literal, \
+             true, false, `, -, import, this, typeof, {, [, ("
+        )
     }
 
     /// `tsParseArrayTypeOrHigher`

ecmascript/parser/src/token.rs

@@ -14,7 +14,7 @@ use swc_common::Span;
 pub(crate) use swc_ecma_ast::AssignOp as AssignOpToken;
 use swc_ecma_ast::BinaryOp;
 
-#[derive(Kind, Debug, Clone, PartialEq)]
+#[derive(Kind, Clone, PartialEq)]
 #[kind(functions(starts_expr = "bool", before_expr = "bool"))]
 pub enum Token {
     /// Identifier, "null", "true", "false".
@@ -568,3 +568,51 @@ impl Word {
         }
     }
 }
+
+impl Debug for Token {
+    /// This method is called only in the case of parsing failure.
+    #[cold]
+    #[inline(never)]
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        match self {
+            Token::Word(w) => write!(f, "{:?}", w)?,
+            Arrow => write!(f, "=>")?,
+            Hash => write!(f, "#")?,
+            At => write!(f, "@")?,
+            Dot => write!(f, ".")?,
+            DotDotDot => write!(f, "...")?,
+            Bang => write!(f, "!")?,
+            LParen => write!(f, "(")?,
+            RParen => write!(f, ")")?,
+            LBracket => write!(f, "[")?,
+            RBracket => write!(f, "]")?,
+            LBrace => write!(f, "{{")?,
+            RBrace => write!(f, "}}")?,
+            Semi => write!(f, ";")?,
+            Comma => write!(f, ",")?,
+            BackQuote => write!(f, "`")?,
+            Template { raw, .. } => write!(f, "template token ({})", raw)?,
+            Colon => write!(f, ":")?,
+            ColonColon => write!(f, "::")?,
+            BinOp(op) => write!(f, "{}", BinaryOp::from(*op).as_str())?,
+            AssignOp(op) => write!(f, "{}", op.as_str())?,
+            DollarLBrace => write!(f, "${{")?,
+            QuestionMark => write!(f, "?")?,
+            PlusPlus => write!(f, "++")?,
+            MinusMinus => write!(f, "--")?,
+            Tilde => write!(f, "~")?,
+            Str { value, .. } => write!(f, "string literal ({})", value)?,
+            Regex(exp, flags) => write!(f, "regexp literal ({}, {})", exp, flags)?,
+            Num(..) => write!(f, "numeric literal")?,
+            BigInt(..) => write!(f, "bigint literal")?,
+            JSXName { name } => write!(f, "jsx name ({})", name)?,
+            JSXText { raw } => write!(f, "jsx text ({})", raw)?,
+            JSXTagStart => write!(f, "< (jsx tag start)")?,
+            JSXTagEnd => write!(f, "> (jsx tag end)")?,
+            Shebang(_) => write!(f, "#!")?,
+            Token::Error(_) => write!(f, "<lexing error>")?,
+        }
+
+        Ok(())
+    }
+}

ecmascript/parser/tests/jsx/errors/attribute-empty-expression/input.js.stderr

@@ -1,10 +1,10 @@
-error: Unexpected token Some(JSXTagEnd)
+error: Unexpected token `> (jsx tag end)`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/jsx/errors/attribute-empty-expression/input.js:1:14
   |
 1 | <foo bar={} />
   |              ^
 
-error: TS1109
+error: Expression expected
  --> $DIR/tests/jsx/errors/attribute-empty-expression/input.js:1:13
   |
 1 | <foo bar={} />

ecmascript/parser/tests/jsx/errors/attributes-in-fragment/input.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(AssignOp("="))
+error: Unexpected token `=`. Expected jsx identifier
  --> $DIR/tests/jsx/errors/attributes-in-fragment/input.js:1:6
   |
 1 | < key="nope"></>

ecmascript/parser/tests/jsx/errors/unicode-escape-in-identifier/input.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Word(你))
+error: Unexpected token `你`. Expected jsx identifier
  --> $DIR/tests/jsx/errors/unicode-escape-in-identifier/input.js:1:2
   |
 1 | <\u{2F804}></\u{2F804}>

ecmascript/parser/tests/test262-error-references/fail/0053737b6145994c.js.stderr

@@ -1,4 +1,4 @@
-error: TS1009
+error: Trailing comma is not allowed
  --> $DIR/tests/test262-parser/fail/0053737b6145994c.js:1:6
   |
 1 | var x, ;

ecmascript/parser/tests/test262-error-references/fail/0131cd88c5774915.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(LBrace)
+error: Unexpected token `{`. Expected identifier, string literal, numeric literal or [ for the computed key
  --> $DIR/tests/test262-parser/fail/0131cd88c5774915.js:1:6
   |
 1 | ({get{a}:0})

ecmascript/parser/tests/test262-error-references/fail/043ab1c3982db3cd.js.stderr

@@ -1,4 +1,4 @@
-error: TS1048
+error: A rest parameter cannot have an initializer
  --> $DIR/tests/test262-parser/fail/043ab1c3982db3cd.js:1:15
   |
 1 | function x(...a = 1){}

ecmascript/parser/tests/test262-error-references/fail/0557c70da3f698b5.module.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Comma)
+error: Unexpected token `,`. Expected an identifier
  --> $DIR/tests/test262-parser/fail/0557c70da3f698b5.module.js:1:11
   |
 1 | import {b,,c} from 'a';

ecmascript/parser/tests/test262-error-references/fail/0817f13d2237d8d2.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Word(prop))
+error: Unexpected token `prop`. Expected target
  --> $DIR/tests/test262-parser/fail/0817f13d2237d8d2.js:1:5
   |
 1 | new.prop

ecmascript/parser/tests/test262-error-references/fail/08fa65d2ecddcfbe.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(LBrace)
+error: Expected ,, got Some({)
  --> $DIR/tests/test262-parser/fail/08fa65d2ecddcfbe.js:1:13
   |
 1 | ({ set: s() { } })

ecmascript/parser/tests/test262-error-references/fail/0a225effb5493c00.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Semi, got Some(Num(42.0))
+error: Expected ;, got Some(numeric literal)
  --> $DIR/tests/test262-parser/fail/0a225effb5493c00.js:1:15
   |
 1 | for (const of 42);

ecmascript/parser/tests/test262-error-references/fail/0abefbc80bf651fa.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Semi)
+error: Unexpected token `;`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/0abefbc80bf651fa.js:1:15
   |
 1 | for (let let;;;) {}

ecmascript/parser/tests/test262-error-references/fail/0d4ff79ab93c897a.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Comma)
+error: Unexpected token `,`. Expected identifier, string literal, numeric literal or [ for the computed key
  --> $DIR/tests/test262-parser/fail/0d4ff79ab93c897a.js:1:5
   |
 1 | ({a,,} = 0)

ecmascript/parser/tests/test262-error-references/fail/0dbe57298be12eac.js.stderr

@@ -1,4 +1,4 @@
-error: TS1009
+error: Trailing comma is not allowed
  --> $DIR/tests/test262-parser/fail/0dbe57298be12eac.js:1:6
   |
 1 | var x,;

ecmascript/parser/tests/test262-error-references/fail/0ddab4a1a651034c.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Semi, got Some(RParen)
+error: Expected ;, got Some())
  --> $DIR/tests/test262-parser/fail/0ddab4a1a651034c.js:1:24
   |
 1 | for (let x = 42 in list) process(x);

ecmascript/parser/tests/test262-error-references/fail/0eb4ed330b5d7e2f.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/0eb4ed330b5d7e2f.js:1:1
   |
 1 | ({get a(){}})=0

ecmascript/parser/tests/test262-error-references/fail/11db90549ed49ac3.js.stderr

@@ -1,4 +1,4 @@
-error: TS1009
+error: Trailing comma is not allowed
  --> $DIR/tests/test262-parser/fail/11db90549ed49ac3.js:1:6
   |
 1 | let x,;

ecmascript/parser/tests/test262-error-references/fail/12a3250154ea8ef5.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/12a3250154ea8ef5.js:1:5
   |
 1 | for(let ? b : c in 0);

ecmascript/parser/tests/test262-error-references/fail/12f5bc355427b8f8.js.stderr

@@ -1,4 +1,4 @@
-error: TS1109
+error: Expression expected
  --> $DIR/tests/test262-parser/fail/12f5bc355427b8f8.js:1:4
   |
 1 | () + 0

ecmascript/parser/tests/test262-error-references/fail/143481afd6573e9b.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(Dot)
+error: Expected ,, got Some(.)
  --> $DIR/tests/test262-parser/fail/143481afd6573e9b.js:1:18
   |
 1 | function* a({e: a.b}) {}

ecmascript/parser/tests/test262-error-references/fail/154f02d86fce5e81.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Semi, got Some(RParen)
+error: Expected ;, got Some())
  --> $DIR/tests/test262-parser/fail/154f02d86fce5e81.js:1:22
   |
 1 | for (const x = 0 in y){}

ecmascript/parser/tests/test262-error-references/fail/15de970e269ae56f.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/15de970e269ae56f.js:1:1
   |
 1 | (1 + 1) = 10

ecmascript/parser/tests/test262-error-references/fail/168502012959421f.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/168502012959421f.js:1:5
   |
 1 | for(([a]) of 0);

ecmascript/parser/tests/test262-error-references/fail/16947dc1d11e5e70.js.stderr

@@ -1,4 +1,4 @@
-error: Expected LParen, got Some(Word(yield))
+error: Expected (, got Some(yield)
  --> $DIR/tests/test262-parser/fail/16947dc1d11e5e70.js:1:11
   |
 1 | (function*yield(){})

ecmascript/parser/tests/test262-error-references/fail/17904d9a6b6ec31b.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Dot)
+error: Unexpected token `.`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/17904d9a6b6ec31b.js:1:3
   |
 1 | f(..a)

ecmascript/parser/tests/test262-error-references/fail/1976350e287d5156.js.stderr

@@ -1,4 +1,4 @@
-error: Expected LBrace, got Some(BinOp(Add))
+error: Expected {, got Some(+)
  --> $DIR/tests/test262-parser/fail/1976350e287d5156.js:1:19
   |
 1 | class A extends a + b {}

ecmascript/parser/tests/test262-error-references/fail/1acada3c651821cf.js.stderr

@@ -1,4 +1,4 @@
-error: Expected RBrace, got Some(Semi)
+error: Expected }, got Some(;)
  --> $DIR/tests/test262-parser/fail/1acada3c651821cf.js:1:12
   |
 1 | `hello ${10;test`

ecmascript/parser/tests/test262-error-references/fail/1aefe47e20eb91fa.module.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token None
+error: Unexpected token `<eof>`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/1aefe47e20eb91fa.module.js:1:1
   |
 1 | await

ecmascript/parser/tests/test262-error-references/fail/1b0b9bca042d4440.module.js.stderr

@@ -1,4 +1,4 @@
-error: Expected LBrace, got Some(Num(3.0))
+error: Expected {, got Some(numeric literal)
  --> $DIR/tests/test262-parser/fail/1b0b9bca042d4440.module.js:1:8
   |
 1 | export 3

ecmascript/parser/tests/test262-error-references/fail/1b2e164ac5015a12.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(Dot)
+error: Expected ,, got Some(.)
  --> $DIR/tests/test262-parser/fail/1b2e164ac5015a12.js:1:10
   |
 1 | ({a({e: a.b}){}})

ecmascript/parser/tests/test262-error-references/fail/1bc43dd97a16b9bb.module.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Word(from), got Some(Semi)
+error: Expected from, got Some(;)
  --> $DIR/tests/test262-parser/fail/1bc43dd97a16b9bb.module.js:1:10
   |
 1 | import {};

ecmascript/parser/tests/test262-error-references/fail/1bde73ba53c309c8.js.stderr

@@ -1,4 +1,4 @@
-error: Expected RBracket, got Some(Word(iter))
+error: Expected ], got Some(iter)
  --> $DIR/tests/test262-parser/fail/1bde73ba53c309c8.js:1:12
   |
 1 | ({ *[yield iter]() {} })

ecmascript/parser/tests/test262-error-references/fail/211656c4eaff2d9c.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Arrow)
+error: Unexpected token `=>`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/211656c4eaff2d9c.js:2:1
   |
 2 | => 0

ecmascript/parser/tests/test262-error-references/fail/23368c25ea374e2f.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/23368c25ea374e2f.js:1:1
   |
 1 | (a,b)=(c,d);

ecmascript/parser/tests/test262-error-references/fail/235adc0d4af204c6.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Dot)
+error: Unexpected token `.`. Expected yield, an identifier, [ or {
  --> $DIR/tests/test262-parser/fail/235adc0d4af204c6.js:1:7
   |
 1 | var [a.b] = 0

ecmascript/parser/tests/test262-error-references/fail/245843abef9e72e7.js.stderr

@@ -1,4 +1,4 @@
-error: Expected RBracket, got None
+error: Expected ], got None
  --> $DIR/tests/test262-parser/fail/245843abef9e72e7.js:1:1
   |
 1 | [

ecmascript/parser/tests/test262-error-references/fail/247e71c8786de6b6.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Word(yield))
+error: Unexpected token `yield`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/247e71c8786de6b6.js:1:31
   |
 1 | (function() { "use strict"; f(yield v) })

ecmascript/parser/tests/test262-error-references/fail/25b1013a4046bd70.js.stderr

@@ -1,4 +1,4 @@
-error: Expected RParen, got Some(LParen)
+error: Expected ), got Some(()
  --> $DIR/tests/test262-parser/fail/25b1013a4046bd70.js:1:21
   |
 1 | try {} catch (answer()) {} 

ecmascript/parser/tests/test262-error-references/fail/26c0710a6449872a.module.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Word(a))
+error: Unexpected token `a`. Expected a string literal
  --> $DIR/tests/test262-parser/fail/26c0710a6449872a.module.js:1:20
   |
 1 | export {as b} from a

ecmascript/parser/tests/test262-error-references/fail/2884c585d2f035a5.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/2884c585d2f035a5.js:1:2
   |
 1 | (([a])=0);

ecmascript/parser/tests/test262-error-references/fail/2cbdd5fad4e5332d.js.stderr

@@ -1,4 +1,4 @@
-error: TS1009
+error: Trailing comma is not allowed
  --> $DIR/tests/test262-parser/fail/2cbdd5fad4e5332d.js:2:4
   |
 2 |   y,;

ecmascript/parser/tests/test262-error-references/fail/2d1410e37ecc3647.js.stderr

@@ -1,10 +1,10 @@
-error: Expected LBrace, got None
+error: Expected {, got None
  --> $DIR/tests/test262-parser/fail/2d1410e37ecc3647.js:1:23
   |
 1 | function f(a, ...b = 0)
   |                       ^
 
-error: TS1048
+error: A rest parameter cannot have an initializer
  --> $DIR/tests/test262-parser/fail/2d1410e37ecc3647.js:1:18
   |
 1 | function f(a, ...b = 0)

ecmascript/parser/tests/test262-error-references/fail/2d86a01ca9731879.module.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Word(a))
+error: Unexpected token `a`. Expected a string literal
  --> $DIR/tests/test262-parser/fail/2d86a01ca9731879.module.js:1:19
   |
 1 | export {a,b} from a

ecmascript/parser/tests/test262-error-references/fail/2e8378f658290622.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/2e8378f658290622.js:1:6
   |
 1 | for (+i in {});

ecmascript/parser/tests/test262-error-references/fail/2f95824f19005b11.js.stderr

@@ -1,4 +1,4 @@
-error: RestPatInSetter
+error: Rest pattern is not allowed in setter
  --> $DIR/tests/test262-parser/fail/2f95824f19005b11.js:1:19
   |
 1 | var a = { set foo(...v) {} };

ecmascript/parser/tests/test262-error-references/fail/305ebbf168c6d218.js.stderr

@@ -1,4 +1,4 @@
-error: TS1009
+error: Trailing comma is not allowed
  --> $DIR/tests/test262-parser/fail/305ebbf168c6d218.js:1:6
   |
 1 | let x,

ecmascript/parser/tests/test262-error-references/fail/3118eaa619345896.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RBracket)
+error: Unexpected token `]`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/3118eaa619345896.js:2:3
   |
 2 | */]

ecmascript/parser/tests/test262-error-references/fail/3162394f5bc07198.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Semi, got Some(RParen)
+error: Expected ;, got Some())
  --> $DIR/tests/test262-parser/fail/3162394f5bc07198.js:1:21
   |
 1 | for(const a = 0 in b);

ecmascript/parser/tests/test262-error-references/fail/324ab48c6d89125d.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Dot)
+error: Unexpected token `.`. Expected target
  --> $DIR/tests/test262-parser/fail/324ab48c6d89125d.js:1:20
   |
 1 | function f() { new..target; }

ecmascript/parser/tests/test262-error-references/fail/338848861369f3b7.js.stderr

@@ -1,4 +1,4 @@
-error: TS1014
+error: A rest parameter must be last in a parameter list
  --> $DIR/tests/test262-parser/fail/338848861369f3b7.js:1:11
   |
 1 | (function(...a, b){})

ecmascript/parser/tests/test262-error-references/fail/33bc068464342558.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Colon)
+error: Unexpected token `:`. Expected * for generator, private key, identifier or async
  --> $DIR/tests/test262-parser/fail/33bc068464342558.js:1:10
   |
 1 | (class {a:0})

ecmascript/parser/tests/test262-error-references/fail/33cf50480671cfec.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RParen)
+error: Unexpected token `)`. Expected yield, an identifier, [ or {
  --> $DIR/tests/test262-parser/fail/33cf50480671cfec.js:1:15
   |
 1 | try { } catch() {}

ecmascript/parser/tests/test262-error-references/fail/33d43e9f01bda5ce.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Semi, got Some(RParen)
+error: Expected ;, got Some())
  --> $DIR/tests/test262-parser/fail/33d43e9f01bda5ce.js:1:20
   |
 1 | for (let x = 0 in y){}

ecmascript/parser/tests/test262-error-references/fail/3425ca087ec1adb1.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(Num(3.0))
+error: Expected ,, got Some(numeric literal)
  --> $DIR/tests/test262-parser/fail/3425ca087ec1adb1.js:1:19
   |
 1 | var {x: y = yield 3} = z;

ecmascript/parser/tests/test262-error-references/fail/3558f8c0f0ba825b.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RParen)
+error: Invalid access to super
  --> $DIR/tests/test262-parser/fail/3558f8c0f0ba825b.js:1:43
   |
 1 | class A extends B { constructor() { (super).a(); } }

ecmascript/parser/tests/test262-error-references/fail/363ecb9e2e556694.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(DotDotDot)
+error: Unexpected token `...`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/363ecb9e2e556694.js:1:11
   |
 1 | new f(... ... g);

ecmascript/parser/tests/test262-error-references/fail/364c1c6fe5df4e6c.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Num(42.0))
+error: Unexpected token `numeric literal`. Expected yield, an identifier, [ or {
  --> $DIR/tests/test262-parser/fail/364c1c6fe5df4e6c.js:1:15
   |
 1 | try {} catch (42) {} 

ecmascript/parser/tests/test262-error-references/fail/369676814db0cbbf.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(Dot)
+error: Expected ,, got Some(.)
  --> $DIR/tests/test262-parser/fail/369676814db0cbbf.js:1:14
   |
 1 | ({set a({e: a.b}){}})

ecmascript/parser/tests/test262-error-references/fail/39551fb86dcd3b29.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Semi)
+error: Unexpected token `;`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/39551fb86dcd3b29.js:1:21
   |
 1 | for (const let = 1;;;) {}

ecmascript/parser/tests/test262-error-references/fail/3a3e59edfed719b0.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/3a3e59edfed719b0.js:1:1
   |
 1 | ({ obj:20 }) = 42

ecmascript/parser/tests/test262-error-references/fail/3a9fa392421db6dd.js.stderr

@@ -1,4 +1,4 @@
-error: Expected RBracket, got Some(Comma)
+error: Expected ], got Some(,)
  --> $DIR/tests/test262-parser/fail/3a9fa392421db6dd.js:1:5
   |
 1 | ({[a,b]:0})

ecmascript/parser/tests/test262-error-references/fail/3bbeaf1dd9ca1159.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RBrace)
+error: Unexpected token `}`. Expected identifier
  --> $DIR/tests/test262-parser/fail/3bbeaf1dd9ca1159.js:1:6
   |
 1 | ({ 5 }) => {}

ecmascript/parser/tests/test262-error-references/fail/3f9ce9123e9ea7cb.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Dot)
+error: Unexpected token `.`. Expected yield, an identifier, [ or {
  --> $DIR/tests/test262-parser/fail/3f9ce9123e9ea7cb.js:1:14
   |
 1 | function a([a.b]) {}

ecmascript/parser/tests/test262-error-references/fail/4045c354c559bed0.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RBrace)
+error: Unexpected token `}`. Expected identifier
  --> $DIR/tests/test262-parser/fail/4045c354c559bed0.js:1:4
   |
 1 | ({0} = 0)

ecmascript/parser/tests/test262-error-references/fail/41895c8145489971.js.stderr

@@ -1,4 +1,4 @@
-error: Expected RBrace, got None
+error: Expected }, got None
  --> $DIR/tests/test262-parser/fail/41895c8145489971.js:1:18
   |
 1 | `hello ${10 `test`

ecmascript/parser/tests/test262-error-references/fail/420d5571366f2df6.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(BinOp(Sub))
+error: Unexpected token `-`. Expected yield, an identifier, [ or {
  --> $DIR/tests/test262-parser/fail/420d5571366f2df6.js:1:15
   |
 1 | try {} catch (-x) {} 

ecmascript/parser/tests/test262-error-references/fail/42cb3f2a38cb2930.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RBracket)
+error: Unexpected token `]`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/42cb3f2a38cb2930.js:2:3
   |
 2 | */]

ecmascript/parser/tests/test262-error-references/fail/44dda972051e652d.js.stderr

@@ -1,4 +1,4 @@
-error: TS1094
+error: A `set` accessor must have a corresponding `get` accessor
  --> $DIR/tests/test262-parser/fail/44dda972051e652d.js:1:11
   |
 1 | class A { get prop(x) {} }

ecmascript/parser/tests/test262-error-references/fail/45b295d6c9abe25d.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RBrace)
+error: Unexpected token `}`. Expected identifier, string literal, numeric literal or [ for the computed key
  --> $DIR/tests/test262-parser/fail/45b295d6c9abe25d.js:1:6
   |
 1 | ({ * })

ecmascript/parser/tests/test262-error-references/fail/45cb305cf7a07edd.js.stderr

@@ -1,4 +1,4 @@
-error: TS1094
+error: A `set` accessor must have a corresponding `get` accessor
  --> $DIR/tests/test262-parser/fail/45cb305cf7a07edd.js:1:8
   |
 1 | ({ set prop() {} })

ecmascript/parser/tests/test262-error-references/fail/45db351b2b07663a.module.js.stderr

@@ -1,4 +1,4 @@
-error: Expected LBrace, got Some(BinOp(Div))
+error: Expected {, got Some(/)
  --> $DIR/tests/test262-parser/fail/45db351b2b07663a.module.js:1:8
   |
 1 | export / from a

ecmascript/parser/tests/test262-error-references/fail/48dee14b7a3a3767.module.js.stderr

@@ -1,4 +1,4 @@
-error: TS1005
+error: Expected a semicolon
  --> $DIR/tests/test262-parser/fail/48dee14b7a3a3767.module.js:1:19
   |
 1 | export let[a] = 0 export let[b] = 0

ecmascript/parser/tests/test262-error-references/fail/49624f905645b7d0.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Semi)
+error: Unexpected token `;`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/49624f905645b7d0.js:1:24
   |
 1 | for (let x, y, z, let;;;) {}

ecmascript/parser/tests/test262-error-references/fail/49861fa3ca0ffc30.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Semi, got Some(RParen)
+error: Expected ;, got Some())
  --> $DIR/tests/test262-parser/fail/49861fa3ca0ffc30.js:1:15
   |
 1 | for ((i in {}));

ecmascript/parser/tests/test262-error-references/fail/49edc77061449ae3.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Semi)
+error: Invalid access to super
  --> $DIR/tests/test262-parser/fail/49edc77061449ae3.js:1:42
   |
 1 | class A extends B { constructor() { super; } }

ecmascript/parser/tests/test262-error-references/fail/4a866d4657f5a83a.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Colon)
+error: Unexpected token `:`. Expected * for generator, private key, identifier or async
  --> $DIR/tests/test262-parser/fail/4a866d4657f5a83a.js:1:12
   |
 1 | (class {[3]:0})

ecmascript/parser/tests/test262-error-references/fail/4c3f75c2ad9dc102.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(Word(if))
+error: Unexpected token `if`. Expected this, import, async, function, [ for array literal, { for object literal, @ for decorator, function, class, null, true, false, number, bigint, string, regexp, ` for template literal, (, or an identifier
  --> $DIR/tests/test262-parser/fail/4c3f75c2ad9dc102.js:1:11
   |
 1 | ({ set: s(if) { } })

ecmascript/parser/tests/test262-error-references/fail/4c7ea6a86bafaf0f.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(Dot)
+error: Expected ,, got Some(.)
  --> $DIR/tests/test262-parser/fail/4c7ea6a86bafaf0f.js:1:17
   |
 1 | (function ({e: a.b}) {})

ecmascript/parser/tests/test262-error-references/fail/4daec155c0322d5e.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(Dot)
+error: Expected ,, got Some(.)
  --> $DIR/tests/test262-parser/fail/4daec155c0322d5e.js:1:17
   |
 1 | function a({e: a.b}) {}

ecmascript/parser/tests/test262-error-references/fail/4ee75fab1ccee715.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(RParen)
+error: Invalid access to super
  --> $DIR/tests/test262-parser/fail/4ee75fab1ccee715.js:1:16
   |
 1 | ({ a() { (super).b(); } });

ecmascript/parser/tests/test262-error-references/fail/4ee7b10cd97f554c.js.stderr

@@ -1,4 +1,4 @@
-error: Expected RBracket, got None
+error: Expected ], got None
  --> $DIR/tests/test262-parser/fail/4ee7b10cd97f554c.js:1:2
   |
 1 | [,

ecmascript/parser/tests/test262-error-references/fail/4f0b15bd78646107.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/4f0b15bd78646107.js:1:1
   |
 1 | 1--

ecmascript/parser/tests/test262-error-references/fail/4f6d3aaae5c7ad56.js.stderr

@@ -1,4 +1,4 @@
-error: Unexpected token Some(LParen)
+error: Unexpected token `(`. Expected identifier, string literal, numeric literal or [ for the computed key
  --> $DIR/tests/test262-parser/fail/4f6d3aaae5c7ad56.js:1:6
   |
 1 | var {(a)} = 0

ecmascript/parser/tests/test262-error-references/fail/525c5220320e32ee.js.stderr

@@ -1,4 +1,4 @@
-error: TS1005
+error: Expected a semicolon
  --> $DIR/tests/test262-parser/fail/525c5220320e32ee.js:1:8
   |
 1 | try { }

ecmascript/parser/tests/test262-error-references/fail/52a2eb6caebf1bf7.js.stderr

@@ -1,4 +1,4 @@
-error: TS1009
+error: Trailing comma is not allowed
  --> $DIR/tests/test262-parser/fail/52a2eb6caebf1bf7.js:1:6
   |
 1 | var x,

ecmascript/parser/tests/test262-error-references/fail/537c4a516d7c8d7f.js.stderr

@@ -1,4 +1,4 @@
-error: Expected Comma, got Some(Dot)
+error: Expected ,, got Some(.)
  --> $DIR/tests/test262-parser/fail/537c4a516d7c8d7f.js:1:20
   |
 1 | try {} catch ({e: x.a}) {}

ecmascript/parser/tests/test262-error-references/fail/576b2243fb8c3b54.js.stderr

@@ -1,4 +1,4 @@
-error: TS1094
+error: A `set` accessor must have a corresponding `get` accessor
  --> $DIR/tests/test262-parser/fail/576b2243fb8c3b54.js:1:8
   |
 1 | ({ get prop(x) {} })

ecmascript/parser/tests/test262-error-references/fail/581bedbbce2541be.js.stderr

@@ -1,4 +1,4 @@
-error: TS2406
+error: Invalid left-hand side in 'for...in' statement
  --> $DIR/tests/test262-parser/fail/581bedbbce2541be.js:1:6
   |
 1 | for (i + 1 in {});