perf(parser): add Modifiers::get method

[overlookmotel]

Add a get method to Modifiers that does a fast bitflags check whether the modifier is present before doing slower iteration through the Vec<Modifier>. The fast path is always taken except when there's a syntax error (rare).

[overlookmotel]

• perf(parser): defer calculation of Modifier spans #20823 : 2 dependent PRs (#20824 , #20826 )
• perf(parser): remove branch from parse_modifiers #20821
• perf(parser): reduce Kind to ModifierKind conversions in eat_modifiers_before_declaration #20820
• refactor(parser): shorten code handling illegal modifiers #20781
• perf(parser): fast path for no syntax errors when checking modifiers #20748
• perf(parser): remove a lookahead from eat_modifiers_before_declaration #20755
• refactor(parser): nest modifiers types in modules #20754
• refactor(parser): re-order modifiers code #20753
• perf(parser): store Modifiers on stack #20742
• perf(parser): add Modifiers::get method #20741 👈 (View in Graphite)
• refactor(parser): rename ModifierKinds::empty to none #20740
• refactor(parser): rename ModifierFlags to ModifierKinds #20739
• refactor(parser): simplify ModifierFlags #20738
• refactor(parser): import from std at top level #20737
• refactor(parser): remove Modifier::is_static() #20736
• refactor(parser): remove dead code from modifier parsing #20735
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 53 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing om/03-23-perf_parser_add_modifiers_get_method (126134b) with om/03-23-refactor_parser_rename_modifierkinds_empty_to_none_ (6627f58)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 om/03-23-refactor_parser_rename_modifierkinds_empty_to_none_ (e2043a2) during the generation of this report, so 8e7a5c6 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[Copilot]

Pull request overview

Adds a fast Modifiers::get accessor that first checks the precomputed ModifierKinds bitset before doing a linear scan, and updates a call site to use it when a span-bearing modifier reference is needed.

Changes:

• Add Modifiers::get(kind) to return an Option<&Modifier> with a fast bitset pre-check.
• Use Modifiers::get(ModifierKind::Declare) in class constructor parsing to avoid unconditional iteration.

Reviewed changes

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

File	Description
crates/oxc_parser/src/modifiers.rs	Introduces Modifiers::get using the existing kinds bitset to gate the linear search.
crates/oxc_parser/src/js/class.rs	Switches the declare-constructor diagnostic to use the new get helper.

[graphite-app]

Merge activity

• Mar 26, 1:09 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 26, 1:13 PM UTC: The Graphite merge queue removed this pull request due to downstack failures on PR #20739.
• Mar 26, 1:13 PM UTC: The Graphite merge queue removed this pull request due to downstack failures on PR #20739.
• Mar 26, 1:29 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 26, 1:33 PM UTC: The Graphite merge queue removed this pull request due to downstack failures on PR #20740.
• Mar 26, 1:33 PM UTC: The Graphite merge queue removed this pull request due to downstack failures on PR #20740.
• Mar 26, 1:34 PM UTC: The merge label '0-merge' was removed. This PR will no longer be merged by the Graphite merge queue
• Mar 26, 1:37 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 26, 1:49 PM UTC: Merged by the Graphite merge queue.