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Latest Results

fix(es/fixer): preserve TypeScript operand grouping (#12539) **Description:** The fixer removes parentheses required by TypeScript around casts, instantiations, and low-precedence cast inputs, producing invalid syntax or changing the parsed expression. Preserve grouping across postfix operations, updates, and binary operators—including `(f<T>)!`, `(f<T>)++`, `(value as T).x`, `(value as T) & other`, `((a + b) as T) * c`, and `(a | b) as T`. Retain required innermost `ParenExpr` nodes in place and replace `IndexMap::shift_remove` with indexed span records so nested parenthesis restoration stays linear while preserving comment migration order. **Related issue (if exists):** - Follow-up to #12518

main

6 minutes ago

test(es/transforms): isolate transform timing from AST cloning (#12540) **Description:** The transform benchmarks in `crates/swc_ecma_transforms_typescript/benches/compat.rs` previously cloned the parsed `Program` and dropped the transformed AST inside `b.iter(...)`, mixing per-iteration AST allocation and cleanup into the measured pass time. Switch both the shared runner and `common_typescript` to `b.iter_batched_ref(..., BatchSize::PerIteration)` and mutate the prepared `Program` in place with `module.mutate(...)`, so each iteration measures only the transform execution. **BREAKING CHANGE:** None. **Related issue (if exists):** None.

main

9 minutes ago

fix(es/typescript): analyze runtime containers before erasure Resolve enum values, alias dependencies and runtime requirements against shared declaration identities before syntax erasure. Track AST declaration order and execution regions, including eager decorator evaluation. Recognize immediately invoked functions through parentheses while retaining type wrappers as analysis boundaries. Substitute eligible enum reads while the original AST is intact, then pass immutable facts to lowering. Preserve reference operations and distinct emitted object identities, and accumulate namespace instantiation without repeated subtree scans.

fix/ts-namespace-enum-bindings

9 minutes ago

fix(es/codegen): emit space after div if rhs starts with a regex

baltasarblanco:fix/12530-regex-after-division

20 minutes ago

fix(es/minifier): mark variables assigned in a member object as accessed and mutated

baltasarblanco:fix/12529-array-literal-param-element-read

50 minutes ago

fix(es/typescript): analyze runtime containers before erasure Resolve enum values, alias dependencies and runtime requirements against shared declaration identities before syntax erasure. Track AST declaration order and execution regions, including eager decorator evaluation. Recognize immediately invoked functions through parentheses while retaining type wrappers as analysis boundaries. Substitute eligible enum reads while the original AST is intact, then pass immutable facts to lowering. Preserve reference operations and distinct emitted object identities, and accumulate namespace instantiation without repeated subtree scans.

fix/ts-namespace-enum-bindings

7 hours ago

fix(es/typescript): evaluate decorators in their enclosing region Method and parameter decorators execute during class evaluation. Keep their enum initializers in the enclosing execution region so later declarations cannot be folded across a temporal dead zone, while parameter initializers and function bodies remain deferred.

fix/ts-namespace-enum-bindings

9 hours ago

fix(es/typescript): analyze runtime containers before erasure Resolve enum values, alias dependencies, and runtime container requirements against shared declaration identities before syntax erasure. Use AST declaration order and execution regions for both enum members and ordinary constants, checking each use before reading cached values. Substitute enum reads in the same pre-erasure traversal and pass immutable facts to lowering. Keep emitted namespace and enum object identities separate from source bindings, preserve reference operations, and accumulate namespace instantiation without repeated subtree scans.

fix/ts-namespace-enum-bindings

10 hours ago

Latest Branches

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fix(es/codegen): emit space after div if rhs starts with a regex#12544

48 minutes ago

35d3849

baltasarblanco:fix/12530-regex-after-division

0%

fix(es/minifier): mark variables assigned in a member object as accessed and mutated#12543

8 hours ago

46ed8d9

baltasarblanco:fix/12529-array-literal-param-element-read

+3%

fix(es/typescript): Fix merged namespace bindings and enum evaluation#12455

8 hours ago

0f01277

fix/ts-namespace-enum-bindings

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