fix(minifier): bail optimizing Array with unknown arg count#22188
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fixes #22185 From the ECMAScript Spec: ``` 23.1.1.1 Array ( ...values ) This function performs the following steps when called: 1. If NewTarget is undefined, let newTarget be the [active function object](https://tc39.es/ecma262/#active-function-object); else let newTarget be NewTarget. 2. Let proto be ? [GetPrototypeFromConstructor](https://tc39.es/ecma262/#sec-getprototypefromconstructor)(newTarget, "%Array.prototype%"). 3. Let numberOfArgs be the number of elements in values. 4. If numberOfArgs = 0, return ! [ArrayCreate](https://tc39.es/ecma262/#sec-arraycreate)(0, proto). 5. If numberOfArgs = 1, then a. Let len be values[0]. b. Let array be ! [ArrayCreate](https://tc39.es/ecma262/#sec-arraycreate)(0, proto). c. If len [is not a Number](https://tc39.es/ecma262/#sec-ecmascript-language-types-number-type), then i. Perform ! [CreateDataPropertyOrThrow](https://tc39.es/ecma262/#sec-createdatapropertyorthrow)(array, "0", len). ii. Let intLen be 1𝔽. d. Else, i. Let intLen be ! [ToUint32](https://tc39.es/ecma262/#sec-touint32)(len). ii. If [SameValueZero](https://tc39.es/ecma262/#sec-samevaluezero)(intLen, len) is false, throw a RangeError exception. e. Perform ! [Set](https://tc39.es/ecma262/#sec-set-o-p-v-throw)(array, "length", intLen, true). f. Return array. 6. [Assert](https://tc39.es/ecma262/#assert): numberOfArgs ≥ 2. 7. Let array be ? [ArrayCreate](https://tc39.es/ecma262/#sec-arraycreate)(numberOfArgs, proto). 8. Let k be 0. 9. Repeat, while k < numberOfArgs, a. Let propertyKey be ! [ToString](https://tc39.es/ecma262/#sec-tostring)([𝔽](https://tc39.es/ecma262/#%F0%9D%94%BD)(k)). b. Let itemK be values[k]. c. Perform ! [CreateDataPropertyOrThrow](https://tc39.es/ecma262/#sec-createdatapropertyorthrow)(array, propertyKey, itemK). d. Set k to k + 1. 10. [Assert](https://tc39.es/ecma262/#assert): The [mathematical value of](https://tc39.es/ecma262/#mathematical-value-of) array's "length" property is numberOfArgs. 11. Return array. ``` If there is a spread in the arguments, we cannot statically identify the number of arguments - it it incorrect to assume that the spread-ed entry it non-zero in length. We could technically improve this approach by realizing if they are >1 non-spread arguments, then it's ok to move this into an `[]`, but i've left it out of scope of this PR
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### 🚀 Features - 66c9b01 transformer/typescript: Debug_assert that `enum_eval` ran in semantic (#22252) (Dunqing) - ffe6475 minifier: Fold `Array` constructor with safe spreads (#22215) (camc314) ### 🐛 Bug Fixes - d3d0b18 traverse: Handle `ChainElement::TSNonNullExpression` in `GatherNodeParts` (#22247) (leaysgur) - 4e880de transformer/object-rest-spread: Declare temp vars for computed keys (#22284) (camc314) - a7c3e22 semantic: Clear member write target for computed keys (#22302) (camc314) - 6a8852d codegen: Emit newline after legal-comment orphan flush (#22304) (Dunqing) - 5da9fda transformer/explicit-resource-management: Preserve class names (#22306) (Dunqing) - b5d970f transformer/explicit-resource-management: Preserve class names (#22290) (camc314) - bc54fd4 minifier: Keep function / class names if direct eval is present in the scope (#22241) (sapphi-red) - 7a810c0 minifier: Refresh direct eval flags after DCE (#21787) (Dunqing) - dd88726 transformer/legacy-decorator: Preserve accessor type annotation for emitDecoratorMetadata (#21966) (Dunqing) - 29a3cd7 codegen: Swap mapping/indent order for top-level decls (#22206) (Dunqing) - 73b4f40 minifier: Preserve catch binding with direct eval (#22221) (camc314) - 0e13d17 minifier: Preserve optional chain base side effects (#22219) (camc314) - 0c7c01c transformer/typescript: Inline optional-chain enum member access (#21834) (Dunqing) - a6aff7e codegen: Emit block/array/object end mapping at close char (#22200) (Dunqing) - a099b03 codegen: Emit call end mapping at `)` position, not past it (#22199) (Dunqing) - 5753774 minifier: Cap if-return ternary collapse for firefox (#21841) (Gurupungav Narayanan) - 2493bdd codegen: Correct sourcemap end mappings for closing delimiters (#22001) (Mark Dalgleish) - 3b385e2 minifier: Bail optimizing `Array` with unknown arg count (#22188) (camc314) - 9fa2122 parser: Parse array computed class keys (#22159) (camc314) ### 📚 Documentation - a4a6892 napi/parser: Correct code comment (#22278) (overlookmotel) - 9305373 oxc: Update README (#22178) (camc314) Co-authored-by: Cameron <[email protected]>
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fixes #22185
From the ECMAScript Spec:
If there is a spread in the arguments, we cannot statically identify the number of arguments - it it incorrect to assume that the spread-ed entry it non-zero in length.
We could technically improve this approach by realizing if they are >1 non-spread arguments, then it's ok to move this into an
[], but i've left it out of scope of this PR