Instanceof requires callable or constructable right-hand side #12728
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Fixes #12709
The check for the right-hand side of
instanceof
previously required that the type beany
or a subtype ofFunction
. This is too strict, and breaks if a class has some otherwise-unrelated functions liketoString
,bind
, etc that don't matchFunction.toString
,Function.bind
, etc.This PR loosens the check to allow a right-hand side type with a call or construct signature, even if the type isn't assignable to
Function
.