## Summary
Closes: https://github.com/astral-sh/ruff/issues/14593
The final type of a variable after if-statement without explicit else
branch should be similar to having an explicit else branch.
## Test Plan
Originally failed test cases from the bug are added.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
`bool()` is equal to `False`, and we infer `Literal[False]` for it. Which
means that the test here will fail as soon as we treat the body of
this `if` as unreachable.
## Summary
This came up as part of #12927 when implementing
`SemanticModel::simulate_runtime_load`.
Should be fairly self-explanatory, if the scope returns a binding with
`BindingKind::Annotation` the bottom part of the loop gets skipped, so
there's no chance for `seen_function` to have been updated. So unless
there's something subtle going on here, like function scopes never
containing bindings with `BindingKind::Annotation`, this seems like a
bug.
## Test Plan
`cargo nextest run`
## Summary
This PR fixes a bug in the f-string formatting to not consider the
escaped newlines for `is_multiline`. This is done by checking if the
f-string is triple-quoted or not similar to normal string literals.
This is not required to be gated behind preview because the logic change
for `is_multiline` was added in
https://github.com/astral-sh/ruff/pull/14454.
## Test Plan
Add a test case which formats differently on `main`:
https://play.ruff.rs/ea3c55c2-f0fe-474e-b6b8-e3365e0ede5e
## Summary
This PR gets rid of the `requirements.in` and `requirements.txt` files
in the `scripts/fuzz-parser` directory, and replaces them with
`pyproject.toml` and `uv.lock` files. The script is renamed from
`fuzz-parser` to `py-fuzzer` (since it can now also be used to fuzz
red-knot as well as the parser, following
https://github.com/astral-sh/ruff/pull/14566), and moved from the
`scripts/` directory to the `python/` directory, since it's now a
(uv)-pip-installable project in its own right.
I've been resisting this for a while, because conceptually this script
just doesn't feel "complicated" enough to me for it to be a full-blown
package. However, I think it's time to do this. Making it a proper
package has several advantages:
- It means we can run it from the project root using `uv run` without
having to activate a virtual environment and ensure that all required
dependencies are installed into that environment
- Using a `pyproject.toml` file means that we can express that the
project requires Python 3.12+ to run properly; this wasn't possible
before
- I've been running mypy on the project locally when I've been working
on it or reviewing other people's PRs; now I can put the mypy config for
the project in the `pyproject.toml` file
## Test Plan
I manually tested that all the commands detailed in
`python/py-fuzzer/README.md` work for me locally.
---------
Co-authored-by: David Peter <sharkdp@users.noreply.github.com>
## Summary
fixes: #14608
The logic that was only applied for 3.12+ target version needs to be
applied for other versions as well.
## Test Plan
I've moved the existing test cases for 3.12 only to `f_string.py` so
that it's tested against the default target version.
I think we should probably enabled testing for two target version (pre
3.12 and 3.12) but it won't highlight any issue because the parser
doesn't consider this. Maybe we should enable this once we have target
version specific syntax errors in place
(https://github.com/astral-sh/ruff/issues/6591).
## Summary
Fix panics related to expressions without inferred types in invalid
syntax examples like:
```py
x: f"Literal[{1 + 2}]" = 3
```
where the `1 + 2` expression (and its sub-expressions) inside the
annotation did not have an inferred type.
## Test Plan
Added new corpus test.
## Summary
Remove entry that was prevously fixed in
5a30ec0df6.
## Test Plan
```sh
cargo test -p red_knot_workspace -- --ignored linter_af linter_gz
```
## Summary
This is about the easiest patch that I can think of. It has a drawback
in that there is no real guarantee this won't happen again. I think this
might be acceptable, given that all of this is a temporary thing.
And we also add a new CI job to prevent regressions like this in the
future.
For the record though, I'm listing alternative approaches I thought of:
- We could get rid of the debug/release distinction and just add `@Todo`
type metadata everywhere. This has possible affects on runtime. The main
reason I didn't follow through with this is that the size of `Type`
increases. We would either have to adapt the `assert_eq_size!` test or
get rid of it. Even if we add messages everywhere and get rid of the
file-and-line-variant in the enum, it's not enough to get back to the
current release-mode size of `Type`.
- We could generally discard `@Todo` meta information when using it in
tests. I think this would be a huge drawback. I like that we can have
the actual messages in the mdtest. And make sure we get the expected
`@Todo` type, not just any `@Todo`. It's also helpful when debugging
tests.
closes#14594
## Test Plan
```rs
cargo nextest run --release
```
## Summary
fixes: #13813
This PR fixes a bug in the formatting assignment statement when the
value is an f-string.
This is resolved by using custom best fit layouts if the f-string is (a)
not already a flat f-string (thus, cannot be multiline) and (b) is not a
multiline string (thus, cannot be flattened). So, it is used in cases
like the following:
```py
aaaaaaaaaaaaaaaaaa = f"testeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee{
expression}moreeeeeeeeeeeeeeeee"
```
Which is (a) `FStringLayout::Multiline` and (b) not a multiline.
There are various other examples in the PR diff along with additional
explanation and context as code comments.
## Test Plan
Add multiple test cases for various scenarios.
## Summary
This PR implements new rule discussed
[here](https://github.com/astral-sh/ruff/discussions/14449).
In short, it searches for assert messages which were unintentionally
used as a expression to be matched against.
## Test Plan
`cargo test` and review of `ruff-ecosystem`
Fix#14558
## Summary
- Add `typing.NoReturn` and `typing.Never` to known instances and infer
them as `Type::Never`
- Add `is_assignable_to` cases for `Type::Never`
I skipped emitting diagnostic for when a function is annotated as
`NoReturn` but it actually returns.
## Test Plan
Added tests from
https://github.com/python/typing/blob/main/conformance/tests/specialtypes_never.py
except from generics and checking if the return value of the function
and the annotations match.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
Closes#14588
```py
x: Literal[42, "hello"] = 42 if bool_instance() else "hello"
reveal_type(x) # revealed: Literal[42] | Literal["hello"]
_ = ... if isinstance(x, str) else ...
# The `isinstance` test incorrectly narrows the type of `x`.
# As a result, `x` is revealed as Literal["hello"], but it should remain Literal[42, "hello"].
reveal_type(x) # revealed: Literal["hello"]
```
## Test Plan
mdtest included!
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
This is just a small refactor to remove the `FormatFStringPart` as it's
only used in the case when the f-string is not implicitly concatenated
in which case the only part is going to be `FString`. In implicitly
concatenated f-strings, we use `StringLike` instead.
