Fix var/lexical name hoisting for destructuring patterns#2360
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HoistingScope.ScriptWalker only collected Identifier names when building _varNames and _lexicalNames, silently skipping destructuring patterns (ArrayPattern, ObjectPattern). This caused variables like x in `for await (var [[x] = [1]] of [[]])` to not be hoisted into the function scope, resulting in ReferenceError in strict mode. Use the existing GetBoundNames() method (from AstExtensions) which correctly recurses into all pattern types. This is the same method already used by Engine.Ast.cs and Engine.cs for declaration instantiation. Fixes sebastienros#2354 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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March 25, 2026 05:43
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Summary
HoistingScope.ScriptWalkeronly collectedIdentifiernames when building_varNamesand_lexicalNames, silently skipping destructuring patterns (ArrayPattern,ObjectPattern, etc.)xinfor await (var [[x] = [1]] of [[]])to not be hoisted into the function scope, resulting inReferenceErrorin strict mode (sloppy mode worked because undeclared assignments create implicit globals)GetBoundNames()method (fromAstExtensions) which correctly recurses into all pattern types — the same method already used byEngine.Ast.csandEngine.csfor declaration instantiationTest plan
"use strict"; async function fn() { for await (var [[x] = [1]] of [[]]) print(x); }now prints1(wasReferenceError)async-func-dstr-varandasync-gen-dstr-vartest262 tests pass (632 tests)Fixes #2354
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