fix(parser): reparse all statements with await identifier in unambiguous mode

[Boshen]

Summary

• Fix parsing of await (...) and other cases where await followed by certain tokens was parsed as an identifier instead of an await expression in unambiguous mode
• Commit 92e27b4 only handled await /regex/ but missed other cases

Changes

• Add encountered_await_identifier flag to ParserState to track when await is parsed as identifier
• Set flag in parse_identifier_reference when parsing "await" as identifier in non-await context
• Modify statement parsing to track checkpoints only for statements that actually used await as identifier
• Once ESM detected, enable await context for remaining statements

Test plan

• Added test cases in tasks/coverage/misc/pass/:
  • unambiguous-await-call.js - Tests await (async function () { })();
  • unambiguous-await-in-declaration.js - Tests const x = await (async function () { })();
• All parser tests pass
• All conformance tests pass

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR fixes parsing of await identifiers in unambiguous mode by extending the previous fix (commit 92e27b4) that only handled await /regex/ to cover other cases like await (...) and await in declarations.

Changes:

• Added encountered_await_identifier flag to track when await is parsed as an identifier in non-await contexts
• Modified statement parsing to checkpoint and reparse statements containing await identifiers when ESM syntax is detected
• Added test cases for await (...) call expressions and await in variable declarations

Reviewed changes

Copilot reviewed 3 out of 11 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
crates/oxc_parser/src/state.rs	Adds encountered_await_identifier flag to track await identifier usage
crates/oxc_parser/src/js/statement.rs	Implements checkpoint tracking and reparsing logic for statements with await identifiers
crates/oxc_parser/src/js/expression.rs	Sets flag when parsing await as identifier in non-await contexts
tasks/coverage/misc/pass/unambiguous-await-call.js	Test case for await (...) expression
tasks/coverage/misc/pass/unambiguous-await-in-declaration.js	Test case for await in variable declarations
tasks/coverage/snapshots/*.snap	Updated test snapshots reflecting improved parsing

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[codspeed-hq]

Merging this PR will not alter performance

✅ 42 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing fix/parser-await-reparse-all-statements (57e3184) with main (c98e5b7)²}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

2. No successful run was found on main (5f5ff1b) during the generation of this report, so c98e5b7 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩