Fix special cases where type context is a union#2715
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This helps with the new definition of `dict.get` in typeshed. The fix feels a little ad-hoc, but it seems to fix a real-world issue and doesn't seem to break anything. Fixes #2703.
JukkaL
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Without this change, mypy can't infer proper types for cases like `d.get(k, [])` where it needs type context to infer the type of `[]`. We add the value type to the second argument to `get` using union types, and this provides the context. This doesn't affect the effective signature of `get`, other than providing the type context for mypy. Also removed some related redundant method definitions where we can just inherit the base class definition. This makes it easier to keep the method signatures consistent. Note that this requires a few mypy PRs before mypy will be able to use this effectively: * python/mypy#2718 * python/mypy#2715
gvanrossum
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Jan 20, 2017
Without this change, mypy can't infer proper types for cases like `d.get(k, [])` where it needs type context to infer the type of `[]`. We add the value type to the second argument to `get` using union types, and this provides the context. This doesn't affect the effective signature of `get`, other than providing the type context for mypy. Also removed some related redundant method definitions where we can just inherit the base class definition. This makes it easier to keep the method signatures consistent. Note that this requires a few mypy PRs before mypy will be able to use this effectively: * python/mypy#2718 * python/mypy#2715
hauntsaninja
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Jan 17, 2026
Kind of reverts python#2715. The test cases in that PR still pass Fixes python#20608
hauntsaninja
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Jan 18, 2026
Kind of reverts python#2715. The test cases in that PR still pass Fixes python#20608
hauntsaninja
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Jan 21, 2026
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This helps with the new definition of
dict.getin typeshed.The fix feels a little ad-hoc, but it seems to fix a real-world issue
and doesn't seem to break anything.
Fixes #2703.