refactor(ast): use NonNull for ref casting#24389
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Pull request overview
Refactors the AstKind::ty discriminant read to use std::ptr::NonNull when casting a &AstKind to &AstType, encoding the non-null guarantee in the pointer type rather than relying on as_ref_unchecked on a raw pointer. This aligns with the post-#24381 direction of making unsafe ref-casts more structurally sound.
Changes:
- Update the
AstKindgenerator to emitNonNull::from_ref(self).cast::<AstType>().as_ref()for thety()fast-path. - Regenerate
crates/oxc_ast/src/generated/ast_kind.rsto apply the same change in the produced code.
Reviewed changes
Copilot reviewed 1 out of 2 changed files in this pull request and generated no comments.
| File | Description |
|---|---|
| tasks/ast_tools/src/generators/ast_kind.rs | Switch generator output from ptr::from_ref(...).as_ref_unchecked() to NonNull::from_ref(...).as_ref() for the AstKind::ty discriminant read. |
| crates/oxc_ast/src/generated/ast_kind.rs | Apply the regenerated NonNull-based cast in AstKind::ty and update imports accordingly. |
Merge activity
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Footnotes
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Follow-on after #24381. When casting a `&` reference, it's preferable to use `NonNull` - that safely gains the "pointer is not null" fact, rather than unsafely promising it with `as_ref_unchecked` on a raw pointer.
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Follow-on after #24381. When casting a
&reference, it's preferable to useNonNull- that safely gains the "pointer is not null" fact, rather than unsafely promising it withas_ref_uncheckedon a raw pointer.