feat(parser): improve error message when JSX is found while not enabled

[sapphi-red]

Improved the error message when JSX syntax is found while not enabled.

The idea came from esbuild's error message (esbuild try).

Before

  x Unexpected token
   ,-[:1:20]
 1 | export const foo = <Foo />;
   :                    ^
   `----

After

  × Unexpected JSX expression
   ╭─[misc/fail/jsx-in-js.js:1:20]
 1 │ export const foo = <Foo />;
   ·                    ───────
   ╰────
  help: JSX syntax is disabled and should be enabled via the parser options

[sapphi-red]

• feat(parser): improve error message for invalid switch clauses #15728
• feat(parser): improve import source from error message #15727
• feat(parser): improve error message for missing function body #15726
• feat(parser): improve error message when JSX is found while not enabled #15725 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #15725 will not alter performance

_{Comparing 11-16-feat_parser_improve_error_when_encountering_jsx_when_not_enabled (62a83f5) with main (d8d4e31)¹}

Summary

✅ 37 untouched

Footnotes

1. No successful run was found on main (4608549) during the generation of this report, so d8d4e31 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Copilot]

Pull Request Overview

This PR improves the error message when JSX syntax is encountered in JavaScript files where JSX parsing is not enabled, inspired by esbuild's error handling.

• Adds a new diagnostic message jsx_in_non_jsx that provides helpful guidance
• Implements detection logic that attempts to parse JSX and provides context-specific errors
• Adds test cases to verify correct error messages for both valid JSX and JSX-like syntax

Reviewed Changes

Copilot reviewed 2 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/oxc_parser/src/diagnostics.rs	Adds new jsx_in_non_jsx diagnostic function with helpful error message
crates/oxc_parser/src/js/expression.rs	Implements JSX detection logic in parse_simple_unary_expression when < is encountered in non-JSX mode
tasks/coverage/misc/fail/jsx-in-js.js	New test file with valid JSX syntax to verify improved error message
tasks/coverage/misc/fail/jsx-like-in-js.js	New test file with invalid JSX-like syntax to verify fallback to generic error
tasks/coverage/snapshots/parser_misc.snap	Updates test snapshots showing improved error messages for the new test cases
tasks/coverage/snapshots/parser_babel.snap	Updates existing Babel test snapshots that now show improved JSX error messages
tasks/coverage/snapshots/parser_typescript.snap	Updates existing TypeScript test snapshots with improved JSX error messages

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[graphite-app]

Merge activity

• Nov 16, 2:57 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Nov 16, 3:03 AM UTC: Merged by the Graphite merge queue.