[defer-import-eval] fixing expectation for super property access#4999
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[defer-import-eval] fixing expectation for super property access#4999
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caiolima
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Mar 20, 2026
…ects Object::SetSuperProperty was short-circuiting to TypeError when the OWN lookup on the receiver hit MODULE_NAMESPACE, skipping the [[GetOwnProperty]] call that OrdinarySetWithOwnDescriptor[1] requires per spec (step 2.c). This meant deferred module evaluation was not triggered and TDZ bindings incorrectly threw TypeError instead of ReferenceError. The fix replaces the MODULE_NAMESPACE case with a GetOwnPropertyDescriptor call that mirrors the existing INTERCEPTOR/JSPROXY path. This properly invokes the namespace's [[GetOwnProperty]], which: - Triggers deferred module evaluation for non-symbol-like string keys - Throws ReferenceError for uninitialized (TDZ) bindings - Returns a writable descriptor for initialized exports, falling through to DefineOwnProperty which rejects the value change (TypeError) Also marks two test262 tests as FAIL (ignore-super-property-set-exported and ignore-super-property-set-not-exported) whose expectations are incorrect per tc39/test262#4999. For a detailed flow on how spec flows to thse cases, see: tc39/test262#4980 [1] - https://tc39.es/ecma262/#sec-ordinarysetwithowndescriptor
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This PR actually changes a couple of tests we have using
super.propthat are incorrect. They expect that a deferred module won't trigger, however they should trigger evaluation, because the execution path eventually calls[[GetOwnProperty]]on deferred namespaces.It closes #4980.