feat(parser): add more help messages to diagnostics

[sapphi-red]

Added more helps to parser errors to make it easier to understand why the error happens or how it can be resolved.

[sapphi-red]

• feat(parser): add more help messages to diagnostics #15440 : 2 dependent PRs (#15441 , #15444 ) 👈 (View in Graphite)
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #15440 will not alter performance

_{Comparing 11-05-feat_parser_add_more_help_messages_to_diagnostics (b5dc76a) with main (89adad0)¹}

Summary

✅ 37 untouched

Footnotes

1. No successful run was found on main (7763029) during the generation of this report, so 89adad0 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 enhances error messages in the TypeScript parser by adding helpful context to diagnostic messages. The changes improve user experience by providing actionable guidance when errors occur.

Key changes:

• Added help text to TypeScript constructor and arrow function parameter errors
• Capitalized help message for super usage errors for consistency
• Enhanced JSX closing tag mismatch errors with clearer labels showing which tag was opened and what closing tag is expected
• Added explanatory help messages for private identifiers with accessibility modifiers and import equals statements

Reviewed Changes

Copilot reviewed 2 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
crates/oxc_parser/src/diagnostics.rs	Added help messages and improved error formatting for TS constructor type parameters, arrow function this parameters, super usage, JSX tag mismatches, private identifiers, and import equals statements
tasks/transform_conformance/snapshots/babel.snap.md	Updated snapshots to reflect new help messages for private identifiers
tasks/coverage/snapshots/parser_typescript.snap	Updated snapshots with all new help messages including super, constructor type parameters, JSX improvements, and import equals
tasks/coverage/snapshots/parser_test262.snap	Updated snapshot for capitalized super help message
tasks/coverage/snapshots/parser_misc.snap	Updated snapshots for improved JSX closing tag error messages
tasks/coverage/snapshots/parser_babel.snap	Updated snapshots for capitalized super help message and new help messages for private identifiers and constructor type parameters

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[Boshen]

Merge activity

• Nov 8, 4:27 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Nov 8, 4:27 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Nov 8, 4:33 AM UTC: Merged by the Graphite merge queue.