feat(ast)!: add `Ident` type by Boshen · Pull Request #18354 · oxc-project/oxc

Boshen · 2026-01-21T15:31:57Z

feat(span): add Ident type

Add a dedicated identifier string type that mirrors the Atom API.
This provides a foundation for future optimizations like pre-computed
hashing while maintaining API compatibility.

refactor(ast): use Ident type for identifier names in JS AST

Replace Atom<'a> with Ident<'a> for the name field in:

IdentifierName
IdentifierReference
BindingIdentifier
LabelIdentifier
PrivateIdentifier

This builds on the Ident type added in the previous commit, providing
semantic distinction for identifier strings and enabling future
optimizations like pre-computed hashing.

Co-Authored-By: Claude Opus 4.5 noreply@anthropic.com

Boshen · 2026-01-21T15:32:18Z

refactor(ast): use Ident for TSIndexSignatureName::name #18357
feat(ast)!: add Ident type #18354 👈 (View in Graphite)
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Boshen · 2026-01-21T16:21:44Z

Merge activity

Jan 21, 4:21 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
Jan 22, 1:45 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 22, 4:46 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 22, 5:13 AM UTC: Boshen added this pull request to the Graphite merge queue.
Jan 22, 5:19 AM UTC: Merged by the Graphite merge queue.

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Pull request overview

This PR introduces a new Ident type for identifier strings and replaces Atom<'a> with Ident<'a> for the name field in JavaScript AST identifier nodes. This provides semantic distinction for identifier strings and lays groundwork for future optimizations like pre-computed hashing.

Changes:

Adds new Ident<'a> type in oxc_span with an API mirroring Atom
Updates AST definitions to use Ident<'a> for identifier name fields in IdentifierName, IdentifierReference, BindingIdentifier, LabelIdentifier, and PrivateIdentifier
Updates code generation tools and all usage sites across transformers, linters, semantic analysis, and other components to handle the type change

Reviewed changes

Copilot reviewed 64 out of 66 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
crates/oxc_span/src/ident.rs	New `Ident` type implementation with full API
crates/oxc_span/src/lib.rs	Exports the new `Ident` type
crates/oxc_ast/src/ast/js.rs	Updates identifier struct fields from `Atom` to `Ident`
crates/oxc_ast/src/generated/ast_builder.rs	Generated builder methods updated for `Ident` parameters
crates/oxc_ast/src/ast_impl/*.rs	Helper methods updated to convert `Ident` to `Atom` where needed
crates/oxc_ast/src/ast_kind_impl.rs	AST kind helpers updated for `Ident` return types
crates/oxc_ast/src/serialize/*.rs	Serialization updated for `Ident` fields
tasks/ast_tools/src/*/.rs	Code generation tools updated to recognize `Ident` as a primitive type with lifetime
tasks/transform_checker/src/lib.rs	Conversion added when collecting reference names
crates/oxc_transformer/*/.rs	Extensive updates across transformer modules to convert between `Ident` and `Atom`
crates/oxc_semantic/*/.rs	Semantic analysis updated with conversions
crates/oxc_linter/*/.rs	Linter rules updated with conversions
crates/oxc_parser/src/module_record.rs	Module record building updated with conversions
crates/oxc_minifier/src/*/.rs	Minifier updated with conversions
crates/oxc_mangler/src/lib.rs	Mangler updated with conversion
crates/oxc_isolated_declarations/src/*/.rs	Isolated declarations updated with conversions
crates/oxc_formatter/src/*/.rs	Formatter updated with conversions
crates/oxc_traverse/src/context/*.rs	Traverse context helpers updated with conversions
crates/oxc_transformer_plugins/src/*.rs	Transformer plugins updated with conversions

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crates/oxc_transformer_plugins/src/replace_global_defines.rs

overlookmotel · 2026-01-22T02:33:15Z

Could we create a separate crate oxc_string for this type? There's going to be a ton of other code around it once we start optimizing it, and Wtf8Str could live in there too, as can SIMD string search functions etc. I think it's going to outgrow oxc_span pretty quickly.

The change of type is going to create a large breakage for consumers (Rolldown etc), so I figure probably preferable to do it all in one go, rather than move it to a different crate later on and break everyone again.

feat(span): add `Ident` type Add a dedicated identifier string type that mirrors the `Atom` API. This provides a foundation for future optimizations like pre-computed hashing while maintaining API compatibility. refactor(ast): use `Ident` type for identifier names in JS AST Replace `Atom<'a>` with `Ident<'a>` for the `name` field in: - `IdentifierName` - `IdentifierReference` - `BindingIdentifier` - `LabelIdentifier` - `PrivateIdentifier` This builds on the `Ident` type added in the previous commit, providing semantic distinction for identifier strings and enabling future optimizations like pre-computed hashing. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

### 💥 BREAKING CHANGES - 22dec6a semantic: [**BREAKING**] Remove `Scoping::scope_build_child_ids` and all related APIs (#18362) (Dunqing) - 30a4899 oxc: [**BREAKING**] Remove `CompilerInterface::semantic_child_scope_ids` (#18361) (Dunqing) - 777fc40 ast: [**BREAKING**] Add `Ident` type (#18354) (Boshen) - af0ca46 span: [**BREAKING**] Use `ModuleKind::CommonJS` for `SourceType::cjs()` (#18276) (sapphi-red) ### 🚀 Features - 0a02026 semantic: Add TS1499 code to diagnostic (#18557) (camc314) - 8b4618f parser: Add TS1500 code to diagnostic (#18547) (camc314) - 866b6b3 parser: Add TS1048 code to diagnostic (#18546) (camc314) - 1117c44 parser: Add TS1054 code to diagnostic (#18541) (camc314) - e4fcdde semantic: Add TS1053 code to diagnostic (#18539) (camc314) - bcbf396 semantic: Add TS1052 code to diagnostic (#18538) (camc314) - 8155edf semantic: Add TS1049 code to diagnostic (#18535) (camc314) - 51d3b3f parser: Add TS1502 code to diagnostic (#18534) (camc314) - 00854e8 semantic: Add TS2337 error code to super call diagnostic (#18531) (camc314) - 993fd2b parser: Parse unambiguous await with better error messages (#18480) (Boshen) - 8db0e78 linter/plugins: Handle BOMs (#18376) (overlookmotel) - 6ac09e2 linter/plugins: Support source text not being at start of buffer (#18375) (overlookmotel) - 2ef5647 ast: Add escape_raw parameter to template_element builders (#18121) (Boshen) ### 🐛 Bug Fixes - 74d0998 semantic: Update error msg for multiple `default` cases in switch stmt (#18526) (camc314) - c205b0d ast: Remove `ThisExpression` from `TSModuleReference` (#18489) (Boshen) - aed3669 parser: Parse HTML-like comments in unambiguous mode (#18442) (Boshen) - c4132fb parser: Validate accessor parameters in interface method signatures (#18391) (Boshen) - b0cd74d semantic: Allow `var` and `function` with same name in static blocks (#18358) (Boshen) - 6037995 semantic: Allow `new.target` in class field initializers (#18349) (Boshen) - 9a15c6a semantic: Do not rely on spans for node comparison in `Function::bind` (#18296) (overlookmotel) ### ⚡ Performance - 6b600c4 semantic: Skip parent lookup for function declarations in `Function::bind` (#18293) (overlookmotel) - c27ad2d semantic: Move check for function declaration out of `is_function_part_of_if_statement` (#18292) (overlookmotel) - 63eb89e semantic: Skip checking redeclarations for function expressions (#18291) (overlookmotel) - 7c12743 semantic: Skip checking unresolved exports in CommonJS files (#18250) (overlookmotel) - 2349031 allocator: Increase initial chunk size from 512B to 16KB (#18234) (Boshen) ### 📚 Documentation - 8ccd853 npm: Update package homepage URLs and add keywords (#18509) (Boshen) - 9b3165f napi/parser: Clarify when to use `parseAsync` vs `parseSync` (#18486) (Boshen) - 1b59f63 napi/parser: Correct typo in README (#18251) (overlookmotel) - 00ff75f mangler: Fix `top_level` option in example (#18233) (overlookmotel) - 2ddc073 semantic: Fix typo in comment (#18238) (overlookmotel) Co-authored-by: Boshen <1430279+Boshen@users.noreply.github.com>

# Oxlint ### 💥 BREAKING CHANGES - 777fc40 ast: [**BREAKING**] Add `Ident` type (#18354) (Boshen) ### 🚀 Features - 34c3ec3 linter/prefer-logical-operator-over-ternary: Implement fixer (#18545) (camc314) - 019e0aa linter/valid-typeof: Add suggestions if type is misspelled (#18543) (camchenry) - 704c8eb linter/use-isnan: Add more specific error message for equality/inequality (#18542) (camchenry) - 1e99ace linter/use-isnan: Support more `indexOf` cases and improve diagnostic messages (#18537) (camchenry) - bffd134 linter/text-encoding-identifier-case: Add `withDash` option (#18533) (camc314) - 993fd2b parser: Parse unambiguous await with better error messages (#18480) (Boshen) - b4b6247 linter/plugins: `RuleTester` support settings (#18445) (overlookmotel) - 15d69dc linter: Implement react/display-name rule (#18426) (camchenry) - 2fbceae linter: Implement rule docs and config support for rules with tuple config options. (#18372) (connorshea) - 8db0e78 linter/plugins: Handle BOMs (#18376) (overlookmotel) - 6ac09e2 linter/plugins: Support source text not being at start of buffer (#18375) (overlookmotel) - fc3c86b linter: Update 125 rules to raise errors when provided with invalid config options. (#18104) (connorshea) - 2cc6ad2 linter/plugins: Add `ecmaFeatures` to `parserOptions` (#18313) (overlookmotel) ### 🐛 Bug Fixes - 2acf568 linter/plugins: Keep `Infinity` in rule default options (#18550) (overlookmotel) - 332d2ef linter/plugins: Add `jsx` property to `parserOptions.ecmaFeatures` (#18549) (overlookmotel) - 7d9bb1b linter: Update `eslint/func-names` to error on invalid rule config options, improve docs. (#18510) (connorshea) - 9c67974 linter: Improve the jsx-a11y/no-noninteractive-tabindex rule to match original rule logic better (#17848) (connorshea) - 75e7163 vscode: Support json5 for oxfmt (#18502) (Sysix) - c205b0d ast: Remove `ThisExpression` from `TSModuleReference` (#18489) (Boshen) - c51339a oxlint/lsp: Respect code action `source.fixAll` as an alias for `source.fixAll.oxc` (#18366) (Sysix) - 3c0e9b9 oxlint/lsp: Skip dangerous fixes/suggestions for "fix all" code action and command (#18364) (Sysix) - c44c093 linter: Fix behavior of unicorn/catch-error-name to match original rule (#18209) (connorshea) - 9c65aff linter/jsx-a11y: Change `no-autofocus` autofix to suggestion (#18155) (Ben Lowery) - 235c820 linter/unicorn: Fix `prefer-array-some` autofix for `.filter().length` pattern (#18153) (Ben Lowery) - a9925dc linter: Mark fixes in `unicorn/no-null` rule as dangerous. (#18436) (connorshea) - cee29b4 linter: Remove confusing scope from `react/only-export-components` rule diagnostics. (#18434) (connorshea) - aed3669 parser: Parse HTML-like comments in unambiguous mode (#18442) (Boshen) - b8a371d linter: Fix the path used in the gitlab format output (#18165) (connorshea) - e046ea6 linter: `vue/no-lifecycle-after-await` skip looking into arrow functions (#18302) (Sysix) - a9bfbcf linter: Compatibility issue with `DiagnosticData` type in ESLint (#18396) (루밀LuMir) - 10ab424 linter: `react/no_array_index_key` continue search for other attributes (#18409) (Lonami) - 9d776d4 linter: Update `import/no-cycle` rule to error on invalid config options. (#18330) (connorshea) - c163231 linter: Update eslint/sort-imports to validate options. (#18378) (connorshea) - 79bbcff linter: Update `eslint/func-style` to error on invalid configuration options. (#18390) (connorshea) - b871235 linter/plugins: Fix identifying "use strict" directives in scope analysis (#18402) (overlookmotel) - 5985141 linter: Update `jest/prefer-lowercase-title` rule to error on invalid config options. (#18332) (connorshea) - faca4b5 linter/plugins: Tokenize `let`, `static` and `yield` as `Keyword`s (#18368) (overlookmotel) - a3914fd linter/plugins: Allow line number passed to `report` to be 1 over line count (#18341) (overlookmotel) - 88e0896 linter: Update `typescript/no-restricted-types` rule to error on invalid config options. (#18329) (connorshea) - 9eec600 linter: Update `react/jsx-fragments` rule to raise an error on invalid configuration options (#18111) (connorshea) - 0fa969d linter: Update `react/no-will-update-set-state` to error on invalid config options (#18112) (connorshea) - 70e7be4 linter: Update `import/no-unassigned-import` to raise an error when passed invalid config options. (#18108) (connorshea) - 496cac7 linter: Update `unicorn/explicit-length-check` to raise an error when passed invalid config options. (#18107) (connorshea) - 080b1ec linter: Update 5 more rules to error on invalid config options. (#18113) (connorshea) - c5d05dd linter: Update 11 rules to raise an error on invalid config options. (#18109) (connorshea) - 9e359d4 linter/plugins: Set all properties on global vars objects (#18317) (overlookmotel) - 39c7f32 linter/plugins: Set `writeable` flag on variables where defined as globals (#18316) (overlookmotel) - a570693 linter/plugins: Fix `CatchClause` scopes (#18312) (overlookmotel) - 8c98e69 linter: `vitest/prefer-describe-function-title`: Check earlier to avoid false positive (#18177) (Jovi De Croock) - 44be0eb linter/plugins: Set scope analyse settings based on source type (#18306) (overlookmotel) - b9a14fd vscode: Update package.json to restrict a few more config options. (#18270) (Connor Shea) - c1260cb vscode: Update version info formatting. (#18274) (connorshea) - 2f68dc6 vscode: Update notification for client restart to specify tool. (#18273) (connorshea) ### ⚡ Performance - dc931ba linter/no-inner-declarations: Skip scope flags lookup in modules (#18249) (overlookmotel) - 07618a7 linter: Turn off `scope_build_child_ids` for SemanticBuilder (#18360) (Dunqing) - 1aac079 linter/exhaustive-deps: Simplify the logic of checking if the identifier it is a dependency of hook (#18350) (Dunqing) - 591d522 linter/block-scoped-var: Avoid `iter_all_scope_child_ids` by walking references/redeclarations scope ancestors (#18335) (Dunqing) - 2eefd6d linter/plugins: Remove branch from token parsing (#18369) (overlookmotel) ### 📚 Documentation - 698c21d linter: Modernize docs for various React rules (#18559) (connorshea) - 314a47c linter: Clarify the `no-find-dom-node` rule with a note that the method was removed in React 19. (#18556) (connorshea) - 5eff704 linter: Update `no-inner-declarations` to fix config option docs (#18511) (connorshea) - dd5d2f6 linter: Improve diagnostic message in `valid_typeof` rule. (#18507) (connorshea) - 8ccd853 npm: Update package homepage URLs and add keywords (#18509) (Boshen) - 4958233 linter: Add missing "What it does" section in prefer-reflect-apply rule. (#18475) (connorshea) - 2fa83a4 linter: Improve the docs for import/unambiguous. (#18474) (connorshea) - 7b1505c linter: Improve docs for `oxc/only-used-in-recursion` rule. (#18473) (connorshea) - ab506d6 linter/plugins: Correct comment (#18456) (overlookmotel) - 4565c73 linter: `react/display-name`: add docs for config options (#18430) (camchenry) - b95a89f linter: Fix docs for the curly rule. (#18374) (connorshea) - f675eb4 linter: Fix the `react/only-export-components` rule docs. (#18319) (connorshea) - 704db95 linter: "no-unused-vars" extend ignored files section for svelte and astro files (#18304) (Sysix) - 3af4a88 linter: Add "Examples" headers to rules missing them (#18266) (connorshea) # Oxfmt ### 💥 BREAKING CHANGES - 777fc40 ast: [**BREAKING**] Add `Ident` type (#18354) (Boshen) ### 🚀 Features - d71c15d oxfmt: Enable tailwind sort inside xxx-in-js (#18417) (leaysgur) - 52b5003 formatter,oxfmt: Support Angular `@Component({ template, styles })` (#18324) (leaysgur) ### 🐛 Bug Fixes - 224140c oxfmt: Canonicalize `..` component in config path (#18570) (leaysgur) - 30b467e formatter: Preserve trailing comments before the semicolon in class methods without a body (#18446) (Dunqing) - c205b0d ast: Remove `ThisExpression` from `TSModuleReference` (#18489) (Boshen) - 164bbd7 formatter: Preserve trailing comments inside ternary alternate branch (#18433) (Dunqing) - 1c50800 formatter: Use HTML entity escaping for JSX attribute strings (#18385) (Boshen) - 4e156d2 formatter: Preserve parentheses for `in` expressions in arrow function block bodies (#18352) (Boshen) - 7e6c15b oxfmt: Increase Tailwind CSS test timeout for Windows CI (#18339) (Boshen) - 29966eb formatter/dead-code-removal: Handle tailwind sorting (#18321) (leaysgur) - 29f41be formatter: Only expand mapped types when newline immediately follows opening brace (#18087) (Boshen) - 2194552 formatter: Relocate leading comments for single-element union/intersection types (#18083) (Boshen) ### ⚡ Performance - 85ab400 formatter: Store `AstNodes` itself instead of `&'a AstNodes` as the `parent` field of `AstNode` (#18428) (Dunqing) - 194d384 formatter: Reduce AstNode size by 8 bytes using following_span_start (#18347) (Dunqing) - b2df8fb oxfmt: Enable tailwind plugin only for relevant parser (#18418) (leaysgur) ### 📚 Documentation - 8ccd853 npm: Update package homepage URLs and add keywords (#18509) (Boshen) Co-authored-by: Boshen <1430279+Boshen@users.noreply.github.com>

Boshen force-pushed the 01-21-feat_span_add_ident_type_with_pre-computed_hash branch from e25435c to 85810f0 Compare January 21, 2026 15:53

Boshen mentioned this pull request Jan 21, 2026

refactor(ast): use Ident for TSIndexSignatureName::name #18357

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Boshen changed the title ~~feat(span): add Ident type~~ feat(span)!: add Ident type Jan 21, 2026

Boshen marked this pull request as ready for review January 21, 2026 16:20

Boshen requested review from Dunqing, camc314 and overlookmotel as code owners January 21, 2026 16:20

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Boshen changed the title ~~feat(span)!: add Ident type~~ feat(ast)!: add Ident type Jan 22, 2026

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Boshen force-pushed the 01-21-feat_span_add_ident_type_with_pre-computed_hash branch from 85810f0 to c3e14bc Compare January 22, 2026 04:47

graphite-app bot force-pushed the 01-21-feat_span_add_ident_type_with_pre-computed_hash branch from 930e2ff to 777fc40 Compare January 22, 2026 05:13

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release(crates): oxc v0.111.0 #18572

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release(apps): oxlint v1.42.0 && oxfmt v0.27.0 #18573

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feat(ast)!: add `Ident` type#18354

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