## Summary
This removes a hack in the protocol satisfiability check that was
previously needed to work around missing assignability-modeling of
inferable type variables. Assignability of type variables is not
implemented fully, but some recent changes allow us to remove that hack
with limited impact on the ecosystem (and the test suite). The change in
the typing conformance test is favorable.
## Test Plan
* Adapted Markdown tests
* Made sure that this change works in combination with
https://github.com/astral-sh/ruff/pull/20517
## Summary
Closes: https://github.com/astral-sh/ty/issues/1236
This PR fixes a bug where the variadic argument wouldn't match against
the variadic parameter in certain scenarios.
This was happening because I didn't realize that the `all_elements`
iterator wouldn't keep on returning the variable element (which is
correct, I just didn't realize it back then).
I don't think we can use the `resize` method here because we don't know
how many parameters this variadic argument is matching against as this
is where the actual parameter matching occurs.
## Test Plan
Expand test cases to consider a few more combinations of arguments and
parameters which are variadic.
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## Summary
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First contribution so please let me know if I've made a mistake
anywhere. This was aimed to fix#19982, it adds the isolation level to
PYI021 to in the same style as the PIE790 rule.
fixes: #19982
## Test Plan
<!-- How was it tested? -->
I added a case to the PYI021.pyi file where the two rules are present as
there wasn't a case with them both interacting, using the minimal
reproducible example that @ntBre created on the issue (I think I got the
`# ERROR` markings wrong, so please let me know how to fix that if I
did).
---------
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
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## Summary
This PR implements
https://docs.astral.sh/ruff/rules/multiple-starred-expressions/ as a
semantic syntax error
## Test Plan
I have added inline tests as directed in #17412
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
## Summary
Fixes https://github.com/astral-sh/ty/issues/1242
From finding references with the LSP, `FileResolver::path` is only
called once, in `UnifiedFile::path`, so I went through those references,
and it looked safe to make this change in every case. Most of the
references are in the various output formats, where we inherited the
absolute vs relative path decision from Ruff. Two other uses are as
fallbacks if converting a relativized path to a string fails. Finally,
we use the path for sorting and in `UnifiedFile::relative_path`.
## Test Plan
Existing tests, with snapshots updated to show absolute paths (in the
`TestDb` this just added a `/` in front of the file names). I also
updated the GitLab CLI test to set the `CI_PROJECT_DIR` environment
variable and ran a test in GitLab CI:
<img width="613" height="114" alt="image"
src="https://github.com/user-attachments/assets/8ab81dba-54fd-4a24-9110-77ef89293cff"
/>
- Adds test cases exercising file selection by extension with
`--preview` enabled and disabled.
- Adds `INCLUDE_PREVIEW` with file patterns including `*.pyw`.
- In global preview mode, default configuration selects patterns from
`INCLUDE_PREVIEW`.
- Manually tested ruff server with local vscode for both formatting and
linting of a `.pyw` file.
Closes https://github.com/astral-sh/ruff/issues/13246
## Summary
This applies the trick that we use for `builtins.open` to similar
functions that have the same problem. The reason is that the problem
would otherwise become even more pronounced once we add understanding of
the implicit type of `self` parameters, because then something like
`(base_path / "test.bin").open("rb")` also leads to a wrong return type
and can result in false positives.
## Test Plan
New Markdown tests
## Summary
I found this bug while working on #20528.
The minimum reproducible code is:
```python
from __future__ import annotations
from typing import NamedTuple
from ty_extensions import is_disjoint_from, static_assert
class Path(NamedTuple):
prev: Path | None
key: str
static_assert(not is_disjoint_from(Path, Path))
```
A stack overflow occurs when a nominal instance type inherits from
`NamedTuple` and is defined recursively.
This PR fixes this bug.
## Test Plan
mdtest updated
## Summary
Adds a new rule to find and report use of `os.path` or `pathlib.Path` in
async functions.
Issue: #8451
## Test Plan
Using `cargo insta test`
### Summary
This PR includes two changes, both of which are necessary to resolve
https://github.com/astral-sh/ty/issues/1196:
* For a generic class `C[T]`, we previously used `C[Unknown]` as the
upper bound of the `Self` type variable. There were two problems with
this. For one, when `Self` appeared in contravariant position, we would
materialize its upper bound to `Bottom[C[Unknown]]` (which might
simplify to `C[Never]` if `C` is covariant in `T`) when accessing
methods on `Top[C[Unknown]]`. This would result in `invalid-argument`
errors on the `self` parameter. Also, using an upper bound of
`C[Unknown]` would mean that inside methods, references to `T` would be
treated as `Unknown`. This could lead to false negatives. To fix this,
we now use `C[T]` (with a "nested" typevar) as the upper bound for
`Self` on `C[T]`.
* In order to make this work, we needed to allow assignability/subtyping
of inferable typevars to other types, since we now check assignability
of e.g. `C[int]` to `C[T]` (when checking assignability to the upper
bound of `Self`) when calling an instance-method on `C[int]` whose
`self` parameter is annotated as `self: Self` (or implicitly `Self`,
following https://github.com/astral-sh/ruff/pull/18007).
closes https://github.com/astral-sh/ty/issues/1196
closes https://github.com/astral-sh/ty/issues/1208
### Test Plan
Regression tests for both issues.
## Summary
@ibraheemdev notes this example failed
```py
from typing import Callable
class X:
...
def f(callable: Callable[[], X]) -> X:
return callable()
x = f(X)
```
Resolves https://github.com/astral-sh/ty/issues/1210
The issue was that we set the `Self` to the class type instead of the
instance type of the class.
## Test Plan
Fix tests in `is_subtype_of.md`
## Summary
Fixes https://github.com/astral-sh/ty/issues/1218.
This bug doesn't currently cause us any real-world issues, because we
don't yet understand the signatures typeshed gives us for `isinstance()`
and `issubclass()` (typeshed's annotations there use PEP-613 type
aliases). #20107 demonstrates that this will start causing us issues as
soon as we add support for PEP-613 aliases, however, so it makes sense
to fix it now.
## Test Plan
Added mdtests
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## Summary
Fixes#12734
I have started with simply checking if any arguments that are providing
extra values to the log message are calls to `str` or `repr`, as
suggested in the linked issue. There was a concern that this could cause
false positives and the check should be more explicit. I am happy to
look into that if I have some further examples to work with.
If this is the accepted solution then there are more cases to add to the
test and it should possibly also do test for the same behavior via the
`extra` keyword.
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
I have added a new test case and python file to flake8_logging_format
with examples of this anti-pattern.
<!-- How was it tested? -->
## Summary
Fixes#20440
Fix B004 to skip invalid hasattr/getattr calls
- Add argument validation for `hasattr` and `getattr`
- Skip B004 rule when function calls have invalid argument patterns
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## Summary
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Fixes#20035, fixes#19395
This is for deduplicating input paths to avoid processing the same file
multiple times.
This is my first contribution, so I'm sorry if I miss something. Please
tell me if this is needed for this feature.
## Test Plan
<!-- How was it tested? -->
I just added a test `find_python_files_deduplicated` in
eee1020e32/crates/ruff_workspace/src/resolver.rs (L1017)
. This pull request adds changes to `WalkPythonFilesState::finish`,
which is used in `python_files_in_path`, so they affect some commands
such as `analyze`, `format`, `check` and so on. I will add snapshot
tests for them if necessary.
I’ve already confirmed that the same thing happens with ruff check as
well.
```
$ echo "x = 1" > example/foo.py
$ uvx ruff check example example/foo.py
I002 [*] Missing required import: `from __future__ import annotations`
--> /path/to/example/foo.py:1:1
help: Insert required import: `from __future__ import annotations`
I002 [*] Missing required import: `from __future__ import annotations`
--> /path/to/example/foo.py:1:1
help: Insert required import: `from __future__ import annotations`
Found 2 errors.
[*] 2 fixable with the `--fix` option.
```
## Summary
Implements new rule `B912` that requires the `strict=` argument for
`map(...)` calls with two or more iterables on Python 3.14+, following
the same pattern as `B905` for `zip()`.
Closes#20057
---------
Co-authored-by: dylwil3 <dylwil3@gmail.com>
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Co-authored-by: Ibraheem Ahmed <ibraheem@ibraheem.ca>
Now that imports are actually inserted, this should give us some
valuable dog-fooding experience.
Note that we don't currently do any ranking on completions, so until
that is improved, even in-scope completions could suffer. With that
said, this shouldn't have any impact at all in several scenarios (like
completions for attributes on objects).
We don't attempt to fix these yet. I think there are bigger fish to fry.
I came up with these based on this discussion:
https://github.com/astral-sh/ruff/pull/20439#discussion_r2357769518
Here's one example:
```
if ...:
from foo import MAGIC
else:
from bar import MAGIC
MAG<CURSOR>
```
Now in this example, completions will include `MAGIC` from the local
scope. That is, auto-import is involved with that completion. But at
present, auto-import will suggest importing `foo` and `bar` because we
haven't de-duplicated completions yet. Which is fine.
Here's another example:
```
if ...:
import foo as fubar
else:
import bar as fubar
MAG<CURSOR>
```
Now here, there is no `MAGIC` symbol in scope. So auto-import is in
play. Let's assume that the user selects `MAGIC` from `foo` in this
example. (`bar` also has `MAGIC`.)
Since we currently ignore the declaration site for symbols with
multiple possible bindings, the importer today doesn't know that
`fubar` _could_ contain `MAGIC`. But even if it did, what would we do
with that information? Should we do this?
```
if ...:
import foo as fubar
from foo import MAGIC
else:
import bar as fubar
MAGIC
```
Or could we reason that `bar` also has `MAGIC`?
```
if ...:
import foo as fubar
else:
import bar as fubar
fubar.MAGIC
```
But if we did that, we're making an assumption of user intent, since
they *selected* `foo.MAGIC` but not `bar.MAGIC`.
Anyway, I don't think we need to settle on an answer today, but I
wanted to capture some of these tricky cases in tests at the very
least.
## Summary
This PR adds support for unpacking `**kwargs` argument.
This can be matched against any standard (positional or keyword),
keyword-only, or keyword variadic parameter that haven't been matched
yet.
This PR also takes care of special casing `TypedDict` because the key
names and the corresponding value type is known, so we can be more
precise in our matching and type checking step. In the future, this
special casing would be extended to include `ParamSpec` as well.
Part of astral-sh/ty#247
## Test Plan
Add test cases for various scenarios.
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## Summary
Resolves#20033
## Test Plan
unit tests added to the new split function, existing snapshot test
updated.
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Fixes#19887
- flynt(FLY002): When joining only string constants, upgrade raw
single-quoted strings to raw triple-quoted if the resulting
content contains a newline.
- Choose a safe triple-quote delimiter by switching to the opposite
quote style if the preferred triple appears inside the
content.
- Update FLY002 snapshot to include the `\n'.join([r'line1','line2'])`
case.
## Test Plan
I've added one test case to FLY002.py.
<!-- How was it tested? -->
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
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## Summary
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Fixes#20255
Mark single-item-membership-test fixes as always unsafe
- Always set `Applicability::Unsafe` for FURB171 fixes
- Update “Fix safety” docs to reflect always-unsafe behavior
- Expand tests (not in, nested set/frozenset, commented args)
## Test Plan
<!-- How was it tested? -->
I have added new test cases to
`crates/ruff_linter/resources/test/fixtures/refurb/FURB171_0.py` and
`crates/ruff_linter/resources/test/fixtures/refurb/FURB171_1.py`.
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
## Summary
Fixes https://github.com/astral-sh/ruff/issues/20134
## Test Plan
`cargo nextest run flake8_use_pathlib`
---------
Co-authored-by: Dan Parizher <danparizher@users.noreply.github.com>
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
This seems to be more consistent with how other LSPs work (like
`rust-analyzer`), and also I think is more consistent with how
`CompletionItem.detail` is itself rendered. Namely, in VS Code, it
is right-aligned. And it's also where we put the type signature.
But `CompletionItemLabelDetails.detail` is left-aligned where as
`CompletionItemLabelDetails.description` is right-aligned. So let's
swap them such that type signatures go in the latter and not the
former.
This also adds a space before the module name and contextualizes
it with `(import <name>)` to help aide the end user in figuring out
selecting the completion will do.
Fixes#1200
## Summary
This change reduces MD test compilation time from 6s to 3s on my laptop.
We don't need to build the unit tests and the corpus tests when we're
only interested in Markdown-based tests.
## Test Plan
local benchmarks
## Summary
Part of https://github.com/astral-sh/ty/issues/168. Infer more precise types for collection literals (currently, only `list` and `set`). For example,
```py
x = [1, 2, 3] # revealed: list[Unknown | int]
y: list[int] = [1, 2, 3] # revealed: list[int]
```
This could easily be extended to `dict` literals, but I am intentionally limiting scope for now.
## Summary
Part of https://github.com/astral-sh/ruff/issues/2331
## Test Plan
`cargo nextest run flake8_use_pathlib`
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
Fixes: https://github.com/astral-sh/ty/issues/1173
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## Summary
This PR will change the logic of binding Self type variables to bind
self to the immediate function that it's used on.
Since we are binding `self` to methods and not the class itself we need
to ensure that we bind self consistently.
The fix is to traverse scopes containing the self and find the first
function inside a class and use that function to bind the typevar for
self.
If no such scope is found we fallback to the normal behavior. Using Self
outside of a class scope is not legal anyway.
## Test Plan
Added a new mdtest.
Checked the diagnostics that are not emitted anymore in [primer
results](https://github.com/astral-sh/ruff/pull/20366#issuecomment-3289411424).
It looks good altough I don't completely understand what was wrong
before.
---------
Co-authored-by: Douglas Creager <dcreager@dcreager.net>
This is somewhat inspired by a similar abstraction in
`ruff_linter`. The main idea is to create an importer once
for a module that you want to add imports to. And then call
`import` to generate an edit for each symbol you want to
add.
I haven't done any performance profiling here yet. I don't
know if it will be a bottleneck. In particular, I do expect
`Importer::import` (but not `Importer::new`) to get called
many times for a single completion request when auto-import
is enabled. Particularly in projects with a lot of unimported
symbols. Because I don't know the perf impact, I didn't do
any premature optimization here. But there are surely some
low hanging fruit if this does prove to be a problem.
New tests make up a big portion of the diff here. I tried to
think of a bunch of different cases, although I'm sure there
are more.
This rejiggers some stuff in the main completions entrypoint
in `ty_ide`. A more refined `Completion` type is defined
with more information. In particular, to support auto-import,
we now include a module name and an "edit" for inserting an
import.
This also rolls the old "detailed completion" into the new
completion type. Previously, we were relying on the completion
type for `ty_python_semantic`. But `ty_ide` is really the code
that owns completions.
Note that this code doesn't build as-is. The next commit will
add the importer used here in `add_unimported_completions`.
Based on how this API is currently implemented, this doesn't
really cost us anything. But it gives us access to more
information about where the symbol is defined.
I think this is a better home for it. This way, `ty_ide`
more clearly owns how the "kind" of a completion is computed.
In particular, it is computed differently for things where
we know its type versus unimported symbols.
In the course of writing the "add an import" implementation,
I realized that we needed to know which symbols were in scope
and how they were defined. This was necessary to be able to
determine how to add a new import in a way that (minimally)
does not conflict with existing symbols.
I'm not sure that this is fully correct (especially for
symbol bindings) and it's unclear to me in which cases a
definition site will be missing. But this seems to work for
some of the basic cases that I tried.
The names of the submodules returned should be *complete*. This
is the contract of `Module::name`. However, we were previously
only returning the basename of the submodule.
This can already be accomplished via a `From` impl (and indeed,
that's how this is implemented). But in a generic context, the
turbo-fishing that needs to be applied is quite annoying.
Basically, given a `from module import name1, name2, ...` statement,
we'd like to be able to insert another name in that list.
This new `Insertion::existing_import` API provides such
functionality. There isn't much to it, although we are careful
to try and avoid inserting nonsense for import statements
that are already invalid.
This refactors the importer abstraction to use a shared
`Insertion`. This is mostly just moving some code around
with some slight tweaks.
The plan here is to keep the rest of the importing code
in `ruff_linter` and then write something ty-specific on
top of `Insertion`. This ends up sharing some code, but
not as much as would be ideal. In particular, the
`ruff_linter` imported is pretty tightly coupled with
ruff's semantic model. So to share the code, we'd need to
abstract over that.
## Summary
This PR wires up the GitHub output format moved to `ruff_db` in #20320
to the ty CLI.
It's a bit smaller than the GitLab version (#20155) because some of the
helpers were already in place, but I did factor out a few
`DisplayDiagnosticConfig` constructor calls in Ruff. I also exposed the
`GithubRenderer` and a wrapper `DisplayGithubDiagnostics` type because
we needed a way to configure the program name displayed in the GitHub
diagnostics. This was previously hard-coded to `Ruff`:
<img width="675" height="247" alt="image"
src="https://github.com/user-attachments/assets/592da860-d2f5-4abd-bc5a-66071d742509"
/>
Another option would be to drop the program name in the output format,
but I think it can be helpful in workflows with multiple programs
emitting annotations (such as Ruff and ty!)
## Test Plan
New CLI test, and a manual test with `--config 'terminal.output-format =
"github"'`
## Summary
Catch infinite recursion in binary-compare inference.
Fixes the stack overflow in `graphql-core` in mypy-primer.
## Test Plan
Added two tests that stack-overflowed before this PR.
## Summary
Use `Type::Divergent` to short-circuit diverging types in type
expressions. This avoids panicking in a wide variety of cases of
recursive type expressions.
Avoids many panics (but not yet all -- I'll be tracking down the rest)
from https://github.com/astral-sh/ty/issues/256 by falling back to
Divergent. For many of these recursive type aliases, we'd like to
support them properly (i.e. really understand the recursive nature of
the type, not just fall back to Divergent) but that will be future work.
This switches `Type::has_divergent_type` from using `any_over_type` to a
custom set of visit methods, because `any_over_type` visits more than we
need to visit, and exercises some lazy attributes of type, causing
significantly more work. This change means this diff doesn't regress
perf; it even reclaims some of the perf regression from
https://github.com/astral-sh/ruff/pull/20333.
## Test Plan
Added mdtest for recursive type alias that panics on main.
Verified that we can now type-check `packaging` (and projects depending
on it) without panic; this will allow moving a number of mypy-primer
projects from `bad.txt` to `good.txt` in a subsequent PR.
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## Summary
This PR implements F406
https://docs.astral.sh/ruff/rules/undefined-local-with-nested-import-star-usage/
as a semantic syntax error
## Test Plan
I have written inline tests as directed in #17412
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
- Convert panics to diagnostics with id `Panic`, severity `Fatal`, and
the error as the diagnostic message, annotated with a `Span` with empty
code block and no range.
- Updates the post-linting message diagnostic handling to track the
maximum severity seen, and then prints the "report a bug in ruff"
message only if the max severity was `Fatal`
This depends on the sorting changes since it creates diagnostics with no
range specified.
Previously, we used a very fine-grained representation for individual
constraints: each constraint was _either_ a range constraint, a
not-equivalent constraint, or an incomparable constraint. These three
pieces are enough to represent all of the "real" constraints we need to
create — range constraints and their negation.
However, it meant that we weren't picking up as many chances to simplify
constraint sets as we could. Our simplification logic depends on being
able to look at _pairs_ of constraints or clauses to see if they
simplify relative to each other. With our fine-grained representation,
we could easily encounter situations that we should have been able to
simplify, but that would require looking at three or more individual
constraints.
For instance, negating a range constraint would produce:
```
¬(Base ≤ T ≤ Super) = ((T ≤ Base) ∧ (T ≠ Base)) ∨ (T ≁ Base) ∨
((Super ≤ T) ∧ (T ≠ Super)) ∨ (T ≁ Super)
```
That is, `T` must be (strictly) less than `Base`, (strictly) greater
than `Super`, or incomparable to either.
If we tried to union those back together, we should get `always`, since
`x ∨ ¬x` should always be true, no matter what `x` is. But instead we
would get:
```
(Base ≤ T ≤ Super) ∨ ((T ≤ Base) ∧ (T ≠ Base)) ∨ (T ≁ Base) ∨ ((Super ≤ T) ∧ (T ≠
Super)) ∨ (T ≁ Super)
```
Nothing would simplify relative to each other, because we'd have to look
at all five union elements to see that together they do in fact combine
to `always`.
The fine-grained representation was nice, because it made it easier to
[work out the math](https://dcreager.net/theory/constraints/) for
intersections and unions of each kind of constraint. But being able to
simplify is more important, since the example above comes up immediately
in #20093 when trying to handle constrained typevars.
The fix in this PR is to go back to a more coarse-grained
representation, where each individual constraint consists of a positive
range (which might be `always` / `Never ≤ T ≤ object`), and zero or more
negative ranges. The intuition is to think of a constraint as a region
of the type space (representable as a range) with zero or more "holes"
removed from it.
With this representation, negating a range constraint produces:
```
¬(Base ≤ T ≤ Super) = (always ∧ ¬(Base ≤ T ≤ Super))
```
(That looks trivial, because it is! We just move the positive range to
the negative side.)
The math is not that much harder than before, because there are only
three combinations to consider (each for intersection and union) —
though the fact that there can be multiple holes in a constraint does
require some nested loops. But the mdtest suite gives me confidence that
this is not introducing any new issues, and it definitely removes a
troublesome TODO.
(As an aside, this change also means that we are back to having each
clause contain no more than one individual constraint for any typevar.
This turned out to be important, because part of our simplification
logic was also depending on that!)
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
This mainly removes an internal inconsistency, where we didn't remove
the `Self` type variable when eagerly binding `Self` to an instance
type. It has no observable effect, apparently.
builds on top of https://github.com/astral-sh/ruff/pull/20328
## Test Plan
None
## Summary
Fixes https://github.com/astral-sh/ty/issues/1161
Include `NamedTupleFallback` members in `NamedTuple` instance
completions.
- Augment instance attribute completions when completing on NamedTuple
instances by merging members from
`_typeshed._type_checker_internals.NamedTupleFallback`
## Test Plan
Adds a minimal completion test `namedtuple_fallback_instance_methods`
---------
Co-authored-by: David Peter <mail@david-peter.de>