chore(tasks): unify printing differences for mismatch code

[Dunqing]

Instead of implementing printing diffs everywhere, use a unified method to make the code cleaner and maintain consistency.

[Dunqing]

• fix(formatter): preserve trailing comments before the semicolon in class methods without a body #18446
• chore(formatter): support --diff in example #18443
• chore(tasks): unify printing differences for mismatch code #18441 👈 (View in Graphite)
• chore(prettier_conformance): improve the information that is shown in filter #18439
• refactor(tasks): improve terminal diff output with context lines #18437
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 42 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing 01-23-chore_tasks_unify_printing_differences_for_mismatch_code (9cf4b23) with 01-23-chore_prettier_conformance_improve_the_information_that_is_shown_in_filter (6271dbb)}

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. ↩

[Boshen]

Merge activity

• Jan 25, 7:02 AM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Jan 26, 5:16 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Jan 26, 5:23 AM UTC: Merged by the Graphite merge queue.

[Copilot]

Pull request overview

This PR centralizes “expected vs actual” diff printing into a single helper (print_diff_in_terminal) and replaces ad-hoc similar::TextDiff usage at call sites.

Changes:

• Add a simple wrapper API (print_diff_in_terminal) in tasks/common to create and print diffs from two strings.
• Update conformance/tests to call the unified diff printer instead of manually constructing TextDiff.
• Remove direct similar dependencies where they’re no longer needed.

Reviewed changes

Copilot reviewed 6 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
tasks/transform_conformance/src/test_case.rs	Switches mismatch diff printing to print_diff_in_terminal.
tasks/transform_conformance/Cargo.toml	Drops direct similar dependency after refactor.
tasks/coverage/Cargo.toml	Adds constcat/cow-utils dependencies (currently appears unrelated to diff refactor).
tasks/common/src/diff.rs	Introduces print_diff_in_terminal wrapper over TextDiff + print_text_diff.
crates/oxc_transformer_plugins/src/module_runner_transform.rs	Updates tests to use print_diff_in_terminal for mismatch output.
crates/oxc_transformer_plugins/Cargo.toml	Removes similar dev-dependency (no longer directly used).
crates/oxc_formatter/Cargo.toml	Removes oxc_tasks_common dev-dependency (but example still uses it).
Cargo.lock	Updates lockfile to reflect dependency changes.

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[leaysgur]

Addressed Copilot review, both seemed valid, we missed updating usage.

I hope it will be merged after CI by Graphite...!