Fix instanceof use with Symbol.hasInstance in conjunction with union/intersection
#57602
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typescript-bot
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Author: Team
For Milestone Bug
sandersn
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Mar 1, 2024
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This fixes an issue with control flow narrowing of
instanceofwhen the right-hand side is either a union or intersection with a[Symbol.hasInstance]method. The original intent was that we would only use[Symbol.hasInstance]if it belonged to an object type, but the implementation didn't account for unions or intersections asgetPropertyOfObjectTypeis specific to immediate object types only. This now instead performs the object type test separately prior to callinggetPropertyOfTypeinstead.Fixes #56536