Only infer 'never' in function expressions and arrow functions #8767
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This PR modifies the type inference rules such that we only infer a function result of
never
in function expressions and arrow functions. For regular functions and methods, in cases where we would have inferrednever
we now instead infervoid
. This matches the behavior we had before the introduction ofnever
and ensures better backwards compatibility. For example:The above pattern is reasonably common and was broken because a
never
returning method cannot be overridden by avoid
returning method.This PR only affects return type inference. It has no impact on functions and methods that explicitly specify a return type.