fix(swc): key optimizer env cache by configured values

[David Murdoch (davidmurdoch)]

Description:

GlobalPassOption::build stores parsed jsc.transform.optimizer.globals.envs maps in a process-wide cache, but the cache key is currently built from globals.vars. Two compilations with the same vars and different explicit envs maps therefore collide, causing the later compilation to reuse stale environment replacements from the earlier one.

Build the cache key from the configured environment map instead, and sort its entries so equivalent maps produce the same key regardless of iteration order.

This was discovered while investigating the cached-span source-map issue fixed by #12129, but it is a separate cache-key bug.

The regression test compiles the same source twice in one process with different explicit environment values. Before the fix, the second compilation incorrectly emits the first value.

Tests:

• cargo fmt --all -- --check
• cargo clippy -p swc --all-targets -- -D warnings
• cargo test -p swc --lib
• cargo test -p swc --test simple
• cargo test -p swc --test simple --features react-compiler
• cargo test -p swc --test rust_api
• cargo test -p swc --test source_map define_source_map_is_stable_across_compilations -- --exact

Related issue (if exists):

Follow-up to #12129.

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Latest commit: 25d8a40

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[chatgpt-codex-connector]

Codex Review Summary

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Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-08-28T23:17:23.991664Z	25d8a40	PR opened

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[codspeed-hq]

Merging this PR will not alter performance

✅ 200 untouched benchmarks
⏩ 61 skipped benchmarks¹

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_{Comparing davidmurdoch:fix/optimizer-globals-cache (25d8a40) with main (e876e80)}

Footnotes

1. 61 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩