Allow properties on type to be accessed
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There are some properties on `builtin.type` that cannot be resolved (e.g. `__mro__`). This is due to attribute lookup used for `type` not handing properties (since `attr.as_instance_method()` is used). This diff implements a hacky workaround. The reason is that we don't have all the arguments to call `call_property_getter` for a proper property resolution. Since builtin types are bundled in typeshed, we can expect the types to be correct, so we use the return type in the property getter. Make 3 more conformance tests pass.
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Diff from mypy_primer, showing the effect of this PR on open source code: discord.py (https://github.com/Rapptz/discord.py)
+ ERROR discord/utils.py:743:24-37: Object of class `type` has no attribute `__slots__` [missing-attribute]
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yangdanny97
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Jan 5, 2026
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Summary
There are some properties on
builtin.typethat cannot be resolved (e.g.__mro__).pyrefly/crates/pyrefly_bundled/third_party/typeshed/stdlib/builtins.pyi
Lines 334 to 335 in 713e5b7
This is due to attribute lookup used for
typenot handing properties (sinceattr.as_instance_method()is used).This diff adds calls to
call_property_getterfor a proper property resolution. Since builtin types are bundled in typeshed, we can expect the types to be correct, so we can use an error swallower.Make 3 more conformance tests pass.
Test Plan
python test.py