fix(parser): fix crashing on empty ParenthesizedExpression with comments

relates #232

crates/oxc_ast/src/span.rs

@@ -28,6 +28,7 @@ impl Span {
 
     #[must_use]
     pub fn len(&self) -> u32 {
+        debug_assert!(self.start <= self.end);
         self.end - self.start
     }
 

crates/oxc_parser/src/js/expression.rs

@@ -196,18 +196,22 @@ impl<'a> Parser<'a> {
         self.ctx = self.ctx.and_in(has_in);
 
         let mut expressions = list.elements;
+        let paren_span = self.end_span(span);
 
         // ParenthesizedExpression is from acorn --preserveParens
         let expression = if expressions.len() == 1 {
             expressions.remove(0)
         } else {
             if expressions.is_empty() {
-                self.error(diagnostics::EmptyParenthesizedExpression(list.span));
+                self.error(diagnostics::EmptyParenthesizedExpression(paren_span));
             }
-            self.ast.sequence_expression(list.span, expressions)
+            self.ast.sequence_expression(
+                Span::new(paren_span.start + 1, paren_span.end - 1),
+                expressions,
+            )
         };
 
-        Ok(self.ast.parenthesized_expression(self.end_span(span), expression))
+        Ok(self.ast.parenthesized_expression(paren_span, expression))
     }
 
     /// Section 13.2.2 This Expression

crates/oxc_parser/src/js/list.rs

@@ -184,13 +184,12 @@ impl<'a> SeparatedList<'a> for CallArguments<'a> {
 }
 
 pub struct SequenceExpressionList<'a> {
-    pub span: Span,
     pub elements: Vec<'a, Expression<'a>>,
 }
 
 impl<'a> SeparatedList<'a> for SequenceExpressionList<'a> {
     fn new(p: &Parser<'a>) -> Self {
-        Self { elements: p.ast.new_vec(), span: Span::default() }
+        Self { elements: p.ast.new_vec() }
     }
 
     fn open(&self) -> Kind {
@@ -201,14 +200,6 @@ impl<'a> SeparatedList<'a> for SequenceExpressionList<'a> {
         Kind::RParen
     }
 
-    fn start_sequence(&mut self, p: &mut Parser) {
-        self.span = p.start_span();
-    }
-
-    fn finish_sequence(&mut self, p: &mut Parser) {
-        self.span = p.end_span(self.span);
-    }
-
     // read everything as expression and map to it to either
     // ParenthesizedExpression or ArrowFormalParameters later
     fn parse_element(&mut self, p: &mut Parser<'a>) -> Result<()> {

crates/oxc_parser/src/lib.rs

@@ -278,6 +278,7 @@ mod test {
 
         let fail = [
             "1<(V=82<<t-j0<(V=$<LBI<(V=ut<I<(V=$<LBI<(V=uIV=82<<t-j0<(V=$<LBI<(V=ut<I<(V=$<LBI<(V<II>",
+            "x = (/* a */)",
         ];
 
         for source in fail {

crates/oxc_parser/src/list.rs

@@ -42,15 +42,11 @@ pub trait SeparatedList<'a>: Sized {
         Kind::Comma
     }
 
-    fn start_sequence(&mut self, _p: &mut Parser<'a>) {}
-    fn finish_sequence(&mut self, _p: &mut Parser<'a>) {}
-
     fn parse_element(&mut self, p: &mut Parser<'a>) -> Result<()>;
 
     /// Main entry point, parse the list
     fn parse_list(&mut self, p: &mut Parser<'a>) -> Result<()> {
         p.expect(self.open())?;
-        self.start_sequence(p);
 
         let mut first = true;
 
@@ -67,7 +63,6 @@ pub trait SeparatedList<'a>: Sized {
             self.parse_element(p)?;
         }
 
-        self.finish_sequence(p);
         p.expect(self.close())?;
         Ok(())
     }

tasks/coverage/babel.snap

@@ -3790,7 +3790,7 @@ Expect to Parse: "typescript/types/const-type-parameters/input.ts"
   × Empty parenthesized expression
    ╭─[es2015/uncategorised/250/input.js:1:1]
  1 │ () <= 42
-   ·  ▲
+   · ──
    ╰────
 
   × Expected a semicolon or an implicit semicolon after a statement, but found none
@@ -4242,7 +4242,7 @@ Expect to Parse: "typescript/types/const-type-parameters/input.ts"
   × Empty parenthesized expression
    ╭─[es2015/uncategorised/38/input.js:1:1]
  1 │ console.log(typeof () => {});
-   ·                     ▲
+   ·                    ──
    ╰────
 
   × Expected `,` but found `=>`
@@ -8348,13 +8348,13 @@ Expect to Parse: "typescript/types/const-type-parameters/input.ts"
   × Empty parenthesized expression
    ╭─[esprima/invalid-syntax/migrated_0095/input.js:1:1]
  1 │ () <= 42
-   ·  ▲
+   · ──
    ╰────
 
   × Empty parenthesized expression
    ╭─[esprima/invalid-syntax/migrated_0096/input.js:1:1]
  1 │ () ? 42
-   ·  ▲
+   · ──
    ╰────
 
   × Expected `:` but found `EOF`
@@ -8365,7 +8365,7 @@ Expect to Parse: "typescript/types/const-type-parameters/input.ts"
   × Empty parenthesized expression
    ╭─[esprima/invalid-syntax/migrated_0097/input.js:1:1]
  1 │ () + 42
-   ·  ▲
+   · ──
    ╰────
 
   × Expected a semicolon or an implicit semicolon after a statement, but found none

tasks/coverage/test262.snap

@@ -9678,7 +9678,7 @@ Negative Passed: 3915/3915 (100.00%)
     ╭─[language/expressions/class/elements/syntax/early-errors/class-heritage-array-literal-arrow-heritage.js:22:1]
  22 │ 
  23 │ var C = class extends () => {} {
-    ·                        ▲
+    ·                       ──
  24 │   
     ╰────
 
@@ -14737,7 +14737,7 @@ Negative Passed: 3915/3915 (100.00%)
     ╭─[language/expressions/in/private-field-invalid-rhs.js:23:1]
  23 │   constructor() {
  24 │     #field in () => {};
-    ·                ▲
+    ·               ──
  25 │   }
     ╰────
 
@@ -20404,14 +20404,14 @@ Negative Passed: 3915/3915 (100.00%)
     ╭─[language/module-code/parse-err-invoke-anon-fun-decl.js:25:1]
  25 │ 
  26 │ export default function() {}();
-    ·                              ▲
+    ·                             ──
     ╰────
 
   × Empty parenthesized expression
     ╭─[language/module-code/parse-err-invoke-anon-gen-decl.js:27:1]
  27 │ 
  28 │ export default function* () {}();
-    ·                                ▲
+    ·                               ──
     ╰────
 
   × TS1108: A 'return' statement can only be used within a function body
@@ -25084,7 +25084,7 @@ Negative Passed: 3915/3915 (100.00%)
     ╭─[language/statements/class/elements/syntax/early-errors/class-heritage-array-literal-arrow-heritage.js:22:1]
  22 │ 
  23 │ class C extends () => {} {
-    ·                  ▲
+    ·                 ──
  24 │   
     ╰────
 
@@ -28812,7 +28812,7 @@ Negative Passed: 3915/3915 (100.00%)
     ╭─[language/statements/expression/S12.4_A1.js:18:1]
  18 │ //CHECK#1
  19 │ function(){}();
-    ·              ▲
+    ·             ──
  20 │ //
     ╰────
 

tasks/coverage/typescript.snap

@@ -8436,7 +8436,7 @@ Expect to Parse: "salsa/privateIdentifierExpando.ts"
   × Empty parenthesized expression
    ╭─[parser/ecmascript5/ErrorRecovery/Expressions/parserErrorRecovery_Expression1.ts:1:1]
  1 │ var v = ()({});
-   ·          ▲
+   ·         ──
    ╰────
 
   × Expected `{` but found `EOF`
@@ -8688,7 +8688,7 @@ Expect to Parse: "salsa/privateIdentifierExpando.ts"
    ╭─[parser/ecmascript5/ErrorRecovery/parserEmptyParenthesizedExpression1.ts:1:1]
  1 │ function getObj() {
  2 │    ().toString();
-   ·     ▲
+   ·    ──
  3 │ }
    ╰────
 
@@ -9218,7 +9218,7 @@ Expect to Parse: "salsa/privateIdentifierExpando.ts"
    ╭─[parser/ecmascript5/RegressionTests/parser509669.ts:1:1]
  1 │ function foo():any {
  2 │  return ():void {};
-   ·          ▲
+   ·         ──
  3 │ }
    ╰────
 
@@ -9268,7 +9268,7 @@ Expect to Parse: "salsa/privateIdentifierExpando.ts"
   × Empty parenthesized expression
    ╭─[parser/ecmascript5/RegressionTests/parser566700.ts:1:1]
  1 │ var v = ()({});
-   ·          ▲
+   ·         ──
    ╰────
 
   × Expected a semicolon or an implicit semicolon after a statement, but found none