fix(es/parser): handle type assertions with non-callable types in binexp#1
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steffen-heil-secforge wants to merge 4 commits into
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fix(es/parser): handle type assertions with non-callable types in binexp#1steffen-heil-secforge wants to merge 4 commits into
steffen-heil-secforge wants to merge 4 commits into
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…ary expressions
After type assertions (`as`) and satisfies expressions, the parser needs to
determine whether a following `<` token is a comparison operator or the start
of type parameters. This fix ensures that `<` is lexed as a comparison operator
when the type cannot have type parameters.
Previously only primitive keyword types and literals were handled. This extends
the logic to cover all non-callable type constructs:
- Primitive keyword types (number, string, boolean, etc.)
- Literal types (2, "x", true, 10n)
- this type
- Array types (number[], Array<number>)
- Tuple types ([number, string])
- Union/intersection types (A | B, A & B)
- Type operators (keyof T, readonly T, unique symbol)
- Indexed access types (T[K])
- Conditional types (T extends U ? X : Y)
- Mapped types ({ [K in keyof T]: V })
- Type predicates (x is string)
This prevents parsing errors when these type assertions are followed by
comparison operators.
Examples that now parse correctly:
- (i as number[]) < 5
- (i as [number, string]) < 5
- (i as number | string) < 5
- (i as keyof T) < 5
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
steffen-heil-secforge
changed the title
Only test files were modified to verify the type assertion handling behavior. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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Jun 28, 2026
…project#11672) ## Summary This PR addresses the highest-impact performance hotspots from swc-project#11667 in `swc_ecma_transformer` (`#1`-`swc-project#4` scope): - Remove repeated front `Vec::insert(0, ...)` patterns in object-rest lowering by using one-shot prepend materialization. - Rewrite object-rest `exit_module_items` export-var rewriting to a single-pass rebuild, avoiding repeated middle `remove/insert` mutations. - Rework statement injector insertion for both `Vec<Stmt>` and `Vec<ModuleItem>` to rebuild once while preserving insertion order and statement-address targeting semantics. - Switch private-in-object class membership tracking (`methods`, `statics`) from `Vec<Atom>` to `FxHashSet<Atom>` for faster membership checks in hot paths. ## Testing - `git submodule update --init --recursive` - `cargo test -p swc_ecma_transformer` - `cargo fmt --all` - `cargo clippy --all --all-targets -- -D warnings` - `cargo test -p swc_ecma_transforms_compat` *(fails in this environment because `mocha` is unavailable for existing exec tests)* - `cargo test -p swc_ecma_transforms_compat --test es2018_object_rest_spread -- --skip exec --skip issue_6029_1 --skip issue_6029_2 --skip issue_4631` ## Notes - No public API changes. - Kept scope intentionally limited to findings `#1`-`swc-project#4`; follow-up work (`swc-project#5`-`swc-project#7`) is not included.
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After type assertions (
as) and satisfies expressions, the parser needs to determine whether a following<token is a comparison operator or the start of type parameters. This fix ensures that<is lexed as a comparison operator when the type cannot have type parameters.Description:
Previously only primitive keyword types and literals were handled. This extends the logic to cover all non-callable type constructs:
This prevents parsing errors when these type assertions are followed by comparison operators.
Examples that now parse correctly: