Underspecified type variables should not infer UninhabitedType

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#3,032 1 comment 1 reaction 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
compilers

Research direction

Locate the testUnderspecifiedInferenceResult test and use it to understand the current inference result for unconstrained TypeVars. Trace the relevant type-inference path, then update the behavior and regression coverage so the test no longer produces UninhabitedType.

Written by the indexing model from the issue text.

Description

bug priority-1-normal topic-type-variables

Unconstrained TypeVars should not infer UninhabitedType as the result -- it leads to confusing behavior.

(See: testUnderspecifiedInferenceResult)

Dominant language
Python
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Forks
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Avg merge
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Merged PRs (30d)
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