fix(semantic): handle var hoisting in catch block with same catch parameter name#12313
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crates/oxc_minifier/src/peephole/substitute_alternate_syntax.rs
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…ameter name (#12313) The root cause is that the variable was hoisted to a scope that has the same name binding ```js var a = 1; try { throw 2 } catch (a) { var a = 3; // ^ Shouldn't hoist to the top scope because there is a same name variable. } console.log(a); ``` Ref: https://tc39.es/ecma262/#sec-variablestatements-in-catch-blocks Note The [Block](https://tc39.es/ecma262/#prod-Block) of a [Catch](https://tc39.es/ecma262/#prod-Catch) clause may contain var declarations that bind a name that is also bound by the [CatchParameter](https://tc39.es/ecma262/#prod-CatchParameter). At runtime, such bindings are instantiated in the VariableDeclarationEnvironment. They do not shadow the same-named bindings introduced by the [CatchParameter](https://tc39.es/ecma262/#prod-CatchParameter) and hence the [Initializer](https://tc39.es/ecma262/#prod-Initializer) for such var declarations will assign to the corresponding catch parameter rather than the var binding.
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The root cause is that the variable was hoisted to a scope that has the same name binding
Ref: https://tc39.es/ecma262/#sec-variablestatements-in-catch-blocks
Note
The Block of a Catch clause may contain var declarations that bind a name that is also bound by the CatchParameter. At runtime, such bindings are instantiated in the VariableDeclarationEnvironment. They do not shadow the same-named bindings introduced by the CatchParameter and hence the Initializer for such var declarations will assign to the corresponding catch parameter rather than the var binding.