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fix(es/minifier): preserve \in\ operator expression statements (#11246) The \in\ operator always has observable side effects: it triggers the \has\ trap on Proxy objects. A bare \key in proxy\ expression statement must therefore never be dropped by the minifier even when its return value is unused. Two code paths were incorrectly treating \in\ as side-effect-free: 1. \may_have_side_effects()\ in swc_ecma_utils handled all BinExpr arms uniformly, only checking whether the operands have side effects. Added a dedicated \BinOp::In\ arm that unconditionally returns true. 2. \ignore_return_value()\ in the compress optimizer had a catch-all BinExpr arm that decomposed any unrecognised binary expression into a sequence of its operands' side effects. For \SYMBOL in obj\ where both operands are pure declared-variable references this reduced to an empty sequence and the statement was silently dropped. Added a dedicated \BinOp::In\ arm before the catch-all that returns \Some(e.take())\, preserving the full expression. Fixes: https://github.com/swc-project/swc/issues/11246

Kaus1ubh:fix/in-operator-side-effect-11246

1 hour ago

Xinkai:xinkai/fix-12430

2 hours ago

fix(es/transforms): keep labels after for await...of

Xinkai:xinkai/fix-12430

3 hours ago

fix(es/minifier): Account for shorthand expansion when inlining Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

LadyBluenotes:fix/object-factory-inline-cost

16 hours ago

fix(es/react-compiler): Grow the stack while converting expressions `convert_expr` and `convert_expression` recurse once per member-call link, so a long chain overflows a 2 MiB thread stack. Wrap both in `stacker::maybe_grow`, behind a default `stacker` feature, matching `swc_ecma_parser`. Refs #12423 Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

BleedingDev:fix/react-compiler-stacker

1 day ago

chore: Add changeset

refactor/parser-contexts-and-construction

1 day ago

chore: Add changeset

refactor/parser-contexts-and-construction

2 days ago

chore: Add changeset

refactor/parser-contexts-and-construction

2 days ago

Latest Branches

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fix(es/minifier): preserve \in\ operator expression statements#12432

1 hour ago

85625cb

Kaus1ubh:fix/in-operator-side-effect-11246

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fix(es/transforms): keep labels after for await...of#12431

2 hours ago

2695505

Xinkai:xinkai/fix-12430

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fix(es/minifier): Account for shorthand expansion when inlining#12428

16 hours ago

8d1e574

LadyBluenotes:fix/object-factory-inline-cost

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