feat(minifier): implement basic single use variable inlining

[sapphi-red]

Ported the basic parts of esbuild's substituteSingleUseSymbolInStmt.
This would allow compressing

let x = fn();
return x;

into

return fn();

[sapphi-red]

• feat(minifier): support remaining expressions for single use variable inlining #13280
• feat(ecmascript): implement MayHaveSideEffects for AssignmentTarget #13279
• feat(minifier): support more statements for single use variable inlining #13277
• feat(minifier): support more expressions for single use variable inlining #13276
• feat(minifier): implement basic single use variable inlining #13275 👈 (View in Graphite)
• feat(minifier): remove unnecessary parenthesis from nested optional chaining #13268
• feat(minifier): remove unused assignments for vars #13231
• fix(minifier): keep variables that are modified by combined assignments made by minification #13267
• fix(minifier): keep property access before call expressions as-is to preserve this value #13278
• main

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[codspeed-hq]

CodSpeed Instrumentation Performance Report

Merging #13275 will degrade performances by 5.72%

_{Comparing 08-24-feat_minifier_implement_basic_single_use_variable_inlining (66d6005) with main (e7a49ed)¹}

Summary

❌ 1 regressions
✅ 33 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
❌	minifier[react.development.js]	2.1 ms	2.3 ms	-5.72%

Footnotes

1. No successful run was found on main (66d6005) during the generation of this report, so e7a49ed was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[graphite-app]

Merge activity

• Aug 24, 8:30 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Aug 24, 8:52 AM UTC: Merged by the Graphite merge queue.