fix(formatter): correct printing comments for the end of union type

[Dunqing]

No description provided.

[Dunqing]

• fix(formatter): print a line break incorrectly for directives #14577
• refactor(formatter): simplify foramtting import and export #14576
• refactor(formatter): remove SiblingNode #14551
• refactor(formatter): improve printing comments for special nodes #14544
• fix(formatter): correct printing comments that are around the StaticMemberExpression #14543
• fix(formatter): no need to wrap a parenthesis for TSConditionalType and TSFunctionType when its parent is TSUnionType and it only has one element #14540
• refactor(formatter): improve line break detaching logic in SourceText #14539
• fix(formatter): missing parenthesis for ComputedMemberExpression when its parent is an NewExpression #14530
• fix(formatter): missing parenthesis for PrivateInExpression when its parent is an UnaryExpression #14529
• fix(formatter): correct printing comments for logical expression #14500
• fix(formatter): should break even if the right side of the assignment is a require when it has a leading own line comment #14499
• fix(formatter): correct printing comments for the end of union type #14498 👈 (View in Graphite)
• fix(formatter): correct printing comments for try statement #14497
• fix(formatter): should expand the parent if the member chain will break #14487
• fix(formatter): correct printing comments around the expression of ComputedMemberExpression #14486
• fix(formatter): correct printing yield argument #14485
• fix(formatter): no need to wrap with parentheses for a type cast node #14484
• fix(formatter): ignore the leading line break for the first argument of the call expression #14483
• fix(formatter): correct checking comments between the operator and the right side for assignment like nodes #14482
• fix(formatter): block comments without a leading linebreak that are around the operator of the conditional expression should be printed as-is #14474
• fix(formatter): correct printing comments for for statements #14473
• fix(formatter): correct printing comments for assignment pattern #14469
• test(formatter): add snapshot-based test infrastructure #14400
• main

---

How to use the Graphite Merge Queue

Add either label to this PR to merge it via the merge queue:

• 0-merge - adds this PR to the back of the merge queue
• hotfix - for urgent hot fixes, skip the queue and merge this PR next

You must have a Graphite account in order to use the merge queue. Sign up using this link.

An organization admin has enabled the Graphite Merge Queue in this repository.

Please do not merge from GitHub as this will restart CI on PRs being processed by the merge queue.

This stack of pull requests is managed by Graphite. Learn more about stacking.

[codspeed-hq]

CodSpeed Performance Report

Merging #14498 will not alter performance

_{Comparing 10-11-fix_formatter_correct_printing_comments_for_the_end_of_union_type (4d55654) with main (626c8f3)¹}

Summary

✅ 33 untouched
⏩ 4 skipped²

Footnotes

1. No successful run was found on main (4d55654) during the generation of this report, so 626c8f3 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 4 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. ↩

[graphite-app]

Merge activity

• Oct 12, 4:12 PM UTC: Dunqing added this pull request to the Graphite merge queue.
• Oct 12, 4:40 PM UTC: The Graphite merge queue couldn't merge this PR because it was not satisfying all requirements (Failed CI: 'Label and Check PR Title').
• Oct 13, 6:15 AM UTC: Dunqing added this pull request to the Graphite merge queue.
• Oct 13, 6:22 AM UTC: Merged by the Graphite merge queue.

[Copilot]

Pull Request Overview

This PR fixes comment printing for union types in the TypeScript formatter. The formatter was previously handling comments incorrectly when they appeared at the end of union types, particularly in cases where the union type doesn't need parentheses.

• Fixed comment handling logic for union types by adding proper conditional checks
• Corrected import path for Formatter type
• Updated comment documentation to be more precise

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
crates/oxc_formatter/src/write/union_type.rs	Added conditional logic to properly handle trailing comments only when union type needs parentheses
crates/oxc_formatter/tests/fixtures/ts/comments/union.ts	Added test case for union type with trailing comment
crates/oxc_formatter/tests/fixtures/ts/comments/union.ts.snap	Test snapshot showing expected formatter output with semicolon addition

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}