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https://github.com/astral-sh/ruff
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5933cc0101
## Summary I wondered if this might improve performance a little. It doesn't seem to, but it's a net reduction in LOC and I think the changes make sense. I think it's worth it anyway just in terms of simplifying the code. ## Test Plan Our existing tests all pass and the primer report is clean (aside from our usual flakes).
2.4 KiB
2.4 KiB
Builtins
Importing builtin module
Builtin symbols can be explicitly imported:
import builtins
reveal_type(builtins.chr) # revealed: def chr(i: SupportsIndex, /) -> str
Implicit use of builtin
Or used implicitly:
reveal_type(chr) # revealed: def chr(i: SupportsIndex, /) -> str
reveal_type(str) # revealed: <class 'str'>
Builtin symbol from custom typeshed
If we specify a custom typeshed, we can use the builtin symbol from it, and no longer access the builtins from the "actual" vendored typeshed:
[environment]
typeshed = "/typeshed"
/typeshed/stdlib/builtins.pyi:
class object: ...
class Custom: ...
custom_builtin: Custom
/typeshed/stdlib/typing_extensions.pyi:
def reveal_type(obj, /): ...
reveal_type(custom_builtin) # revealed: Custom
# error: [unresolved-reference]
reveal_type(str) # revealed: Unknown
Unknown builtin (later defined)
foo has a type of Unknown in this example, as it relies on bar which has not been defined at
that point:
[environment]
typeshed = "/typeshed"
/typeshed/stdlib/builtins.pyi:
foo = bar
bar = 1
/typeshed/stdlib/typing_extensions.pyi:
def reveal_type(obj, /): ...
reveal_type(foo) # revealed: Unknown
Builtins imported from custom project-level stubs
The project can add or replace builtins with the __builtins__.pyi stub. They will take precedence
over the typeshed ones.
reveal_type(foo) # revealed: int
reveal_type(bar) # revealed: str
reveal_type(quux(1)) # revealed: int
b = baz # error: [unresolved-reference]
reveal_type(ord(100)) # revealed: bool
a = ord("a") # error: [invalid-argument-type]
bar = int(123)
reveal_type(bar) # revealed: int
__builtins__.pyi:
foo: int = ...
bar: str = ...
def quux(value: int) -> int: ...
unused: str = ...
def ord(x: int) -> bool: ...
Builtins stubs are searched relative to the project root, not the file using them.
under/some/folder.py:
reveal_type(foo) # revealed: int
reveal_type(bar) # revealed: str
Assigning custom builtins
import builtins
builtins.foo = 123
builtins.bar = 456 # error: [unresolved-attribute]
builtins.baz = 789 # error: [invalid-assignment]
builtins.chr = lambda x: str(x) # error: [invalid-assignment]
builtins.chr = 10
__builtins__.pyi:
foo: int
baz: str
chr: int