dev: Appease Pyright 1.1.345's changed type checking of tuple slices #344
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A slice like x[0:2] may evaluate to ('a',) or ('a', 'b',) depending on
the length of x. Pyright changed its checking of this slice behaviour
for tuples in 1.1.345 (released 4 days ago)¹, which started raising
issues with this code in CI.
While we humans know that the sockaddr tuples here always have at least
two elements, Pyright does not. I think Pyright could do better here as
it knows the type of sockaddr is
Tuple[str, int] | Tuple[str, int, int, int]
and thus I think should be able to know for sure the type of a 0:2
slice. Instead, it evaluates the slice type to an ambiguous
Tuple[str | int, ...]
which is incompatible with our declared return type.
I went to report this behaviour regression, but someone's already beat
me to it.²
¹ <https://github.com/microsoft/pyright/releases/tag/1.1.345>
² <microsoft/pyright#6958>
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A slice like x[0:2] may evaluate to ('a',) or ('a', 'b',) depending on the length of x. Pyright changed its checking of this slice behaviour for tuples in 1.1.345 (released 4 days ago)¹, which started raising issues with this code in CI.
While we humans know that the sockaddr tuples here always have at least two elements, Pyright does not. I think Pyright could do better here as it knows the type of sockaddr is
and thus I think should be able to know for sure the type of a 0:2 slice. Instead, it evaluates the slice type to an ambiguous
which is incompatible with our declared return type.
I went to report this behaviour regression, but someone's already beat me to it.²
¹ https://github.com/microsoft/pyright/releases/tag/1.1.345
² microsoft/pyright#6958
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