Parse each format-string component separately#3390
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gvanrossum merged 5 commits intopython:masterfrom May 30, 2017
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test-data/unit/check-newsyntax.test
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| [case testNewSyntaxFStringSingleField] | ||
| # flags: --python-version 3.6 | ||
| v = 1 | ||
| f'{v}' + '' |
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I'd write reveal_type(f'{v}') # E: Revealed type is 'builtins.str', which tests more explicitly what you want to achieve.
test-data/unit/fixtures/f_string.pyi
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| T = TypeVar('T') | ||
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| @builtinclass |
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Curious, what does this do? I haven't seen it before and grep shows no uses outside of test fixtures.
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I don't know, I think nothing -- maybe it's a relic? I just copied that code from fixtures/list.pyi. I've removed it.
gvanrossum
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Just nits, this is basically right.
mypy/fastparse.py
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| format_args, | ||
| format_arg_kinds) | ||
| """Each of n.values is a str or FormattedValue; we just concatenate | ||
| them all using ''.join.""" |
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I think this should be a comment, not a docstring. Ditto below. (Docstrings are more for the users of a function, comments are for readers of the function body.)
test-data/unit/fixtures/f_string.pyi
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| def __mul__(self, x: int) -> list[T]: pass | ||
| def __getitem__(self, x: int) -> T: pass | ||
| def append(self, x: T) -> None: pass | ||
| def extend(self, x: Iterable[T]) -> None: pass |
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You probably don't need all these methods.
Fixes python#3385. The old code evaluated each FormattedValue as an expression potentially returning the type of the value, rather than a string. But that's wrong, because a FormattedValue can exist on its own when it's not being joined to any other format strings. The new code evaluates each FormattedValue by synthesizing '{}'.format(expr) and then, if necessary, joins them in JoinedStr using ''.join(items).
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Ready for re-review. |
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* master: (23 commits) Make return type of open() more precise (python#3477) Add test cases that delete a file during incremental checking (python#3461) Parse each format-string component separately (python#3390) Don't warn about returning Any if it is a proper subtype of the return type (python#3473) Add __setattr__ support (python#3451) Remove bundled lib-typing (python#3337) Move version of extensions to post-release (python#3348) Fix None slice bounds with strict-optional (python#3445) Allow NewType subclassing NewType. (python#3465) Add console scripts (python#3074) Fix 'variance' label. Change label for variance section to just 'variance' (python#3429) Better error message for invalid package names passed to mypy (python#3447) Fix last character cut in html-report if file does not end with newline (python#3466) Print pytest output as it happens (python#3463) Add mypy roadmap (python#3460) Add flag to avoid interpreting arguments with a default of None as Optional (python#3248) Add type checking plugin support for functions (python#3299) Mismatch of inferred type and return type note (python#3428) Sync typeshed (python#3449) ...
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Fixes #3385.
The old code evaluated each FormattedValue as an expression potentially returning the type of the value, rather than a string. But that's wrong, because a FormattedValue can exist on its own when it's not being joined to any other format strings + those FormattedValues need type str. The new code evaluates each FormattedValue by synthesizing '{}'.format(expr) and then, if necessary, joins them in JoinedStr using ''.join(items).
I had to create a new unittest fixture for this with list, str, and int.