Never put None in TupleType items #4051
Merged
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Fixes #4046
The root cause for the crash is that
None
was put inTupleType
items if the correspondinglvalue
is a definition. Then the crash happens when thisTupleType
is used as a context forrvalue
type inference. The solution is to putUninhabitedType
in such cases, so that inference will fall back on using argument types instead.This PR should not cause any crashes but it makes sense to test it against internal codebases since it touches an area that might alter type inference in corner cases.