refactor(parser): nest modifiers types in modules

[overlookmotel]

Modifiers and ModifierKinds both have safety invariants which their methods uphold. Move them into modules so no other code can directly manipulate their fields and break these invariants.

[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 👈 (View in Graphite)
• refactor(parser): re-order modifiers code #20753
• perf(parser): store Modifiers on stack #20742
• perf(parser): add Modifiers::get method #20741
• 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/03-25-refactor_parser_nest_modifiers_types_in_modules (793034c) with om/03-25-refactor_parser_re-order_modifiers_code (216e6f0)}

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. ↩

[Copilot]

Pull request overview

This PR refactors the parser’s modifier storage types (Modifiers and ModifierKinds) by nesting their concrete implementations in private modules and re-exporting the types, preventing other code from directly manipulating internal fields and breaking their safety invariants.

Changes:

• Move Modifiers into a private mod modifiers and re-export it.
• Move ModifierKinds into a private mod modifier_kinds and re-export it.
• Update internal call sites to use an accessor (modifiers.kinds()) rather than field access.

[graphite-app]

Merge activity

• Mar 26, 1:13 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, 1:36 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 26, 1:37 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 26, 1:52 PM UTC: Merged by the Graphite merge queue.