11cfe2ea8a
## Summary Resolves #15695, rework of #15704. This change modifies the Mdtests framework so that: * Paths must now be specified in a separate preceding line: `````markdown `a.py`: ```py x = 1 ``` ````` If the path of a file conflicts with its `lang`, an error will be thrown. * Configs are no longer accepted. The pattern still take them into account, however, to avoid "Unterminated code block" errors. * Unnamed files are now assigned unique, `lang`-respecting paths automatically. Additionally, all legacy usages have been updated. ## Test Plan Unit tests and Markdown tests. --------- Co-authored-by: Carl Meyer <carl@astral.sh>
2 KiB
Ellipsis
Function and methods
The ellipsis literal ... can be used as a placeholder default value for a function parameter, in a
stub file only, regardless of the type of the parameter.
def f(x: int = ...) -> None:
reveal_type(x) # revealed: int
def f2(x: str = ...) -> None:
reveal_type(x) # revealed: str
Class and module symbols
The ellipsis literal can be assigned to a class or module symbol, regardless of its declared type, in a stub file only.
y: bytes = ...
reveal_type(y) # revealed: bytes
x = ...
reveal_type(x) # revealed: Unknown
class Foo:
y: int = ...
reveal_type(Foo.y) # revealed: int
Unpacking ellipsis literal in assignment
No diagnostic is emitted if an ellipsis literal is "unpacked" in a stub file as part of an assignment statement:
x, y = ...
reveal_type(x) # revealed: Unknown
reveal_type(y) # revealed: Unknown
Unpacking ellipsis literal in for loops
Iterating over an ellipsis literal as part of a for loop in a stub is invalid, however, and
results in a diagnostic:
# error: [not-iterable] "Object of type `ellipsis` is not iterable"
for a, b in ...:
reveal_type(a) # revealed: Unknown
reveal_type(b) # revealed: Unknown
Ellipsis usage in non stub file
In a non-stub file, there's no special treatment of ellipsis literals. An ellipsis literal can only
be assigned if EllipsisType is actually assignable to the annotated type.
# error: 7 [invalid-parameter-default] "Default value of type `ellipsis` is not assignable to annotated parameter type `int`"
def f(x: int = ...) -> None: ...
# error: 1 [invalid-assignment] "Object of type `ellipsis` is not assignable to `int`"
a: int = ...
b = ...
reveal_type(b) # revealed: ellipsis
Use of Ellipsis symbol
There is no special treatment of the builtin name Ellipsis in stubs, only of ... literals.
# error: 7 [invalid-parameter-default] "Default value of type `ellipsis` is not assignable to annotated parameter type `int`"
def f(x: int = Ellipsis) -> None: ...