[js-api] Fix misapplied ECMA-262 ReturnIfAbrupt shorthand (?, !) - #2256
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Ms2ger merged 1 commit intoSep 30, 2026
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Two directions of the same underlying mistake - misreading what the ?/! shorthand actually requires: - [=!=] applied to ToJSValue (7 sites), OrdinaryObjectCreate (3 sites), CreateBuiltinFunction (1 site), and IsStrictlyEqual (2 sites): none of these ever return a Completion Record, so there is nothing for ! to unwrap. ToJSValue's own body is bare Let/Return statements with no Throw/NormalCompletion/ThrowCompletion anywhere; OrdinaryObjectCreate and CreateBuiltinFunction are declared with non-completion return types in ECMA-262; IsStrictlyEqual is declared ': a Boolean'. Every other call site of these same operations elsewhere in this corpus (~40 occurrences of CreateBuiltinFunction alone, in webidl/index.bs) correctly omits the shorthand - these are the sole exceptions. - read the imports is missing [=?=] before [$HasProperty$]: unlike every other [$HasProperty$]/[$Get$] call in this exact algorithm, which are all correctly marked [=?=], this one omission means the fallback branch it's meant to guard (falling back to reading from the plain importObject when a builtin-provided export doesn't have the requested property) can never fire, since the raw Completion Record it produces is compared against the literal false value as a Record, never true.
Ms2ger
approved these changes
Sep 30, 2026
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Two directions of the same underlying mistake - misreading what the ?/! shorthand actually requires:
ToJSValue(7 sites),OrdinaryObjectCreate(3 sites),CreateBuiltinFunction(1 site), andIsStrictlyEqual(2 sites): none of these ever return a Completion Record, so there is nothing for ! to unwrap.ToJSValue's own body is bare Let/Return statements with no Throw / NormalCompletion / ThrowCompletion anywhere;OrdinaryObjectCreateandCreateBuiltinFunctionare declared with non-completion return types in ECMA-262;IsStrictlyEqualis declared with return type ': a Boolean'.read the importsis missing [=?=] beforeHasProperty: unlike every otherHasProperty/Getcall in this exact algorithm, which are all correctly marked [=?=].