## Summary
Since we've already filtered the union in these locations, it seems like
needless overhead to then intersect the previous union with the filtered
union. We know what that intersection will simplify to: it will simplify
to the filtered union. So rather than using a regular intersection-based
constraint, we can use a "typeguard constraint", which will just
directly replace the previous type with the new type instead of creating
an intersection.
## Test Plan
- Existing tests all pass
- The primer report should be clean
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR fixes#20811 , current approach reverses the order in `BtreeSet`
however as pointed in
https://github.com/astral-sh/ruff/issues/20811#issuecomment-3398958832
here we cannot use I`IndexSet` to preserve config order since Settings
derives `CacheKey` which isn't implemented for `IndexSet`, another
approach to preserve the original order might be to use `Vec` however
lookup time complexity might get affected as a result.
<!-- How was it tested? -->
I have tested it locally its working as expected ,
<img width="2200" height="1071" alt="image"
src="https://github.com/user-attachments/assets/7d97b488-1552-4a42-9d90-92acf55ec493"
/>
---------
Signed-off-by: Bhuminjay <bhuminjaysoni@gmail.com>
## Summary
- Adds an alternative example to the PT017 (`pytest-assert-in-except`)
rule documentation showing pytest's `check` parameter for validating
exceptions, available since pytest 8.4.0
Closes#22529
## Test plan
Documentation-only change. Verified with `uvx prek run -a`.
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [invalid-suppression-comment
(RUF103)](https://docs.astral.sh/ruff/rules/invalid-suppression-comment/#invalid-suppression-comment-ruf103)'s
example error out-of-the-box.
[Old example](https://play.ruff.rs/3ff757f3-04ae-4d27-986d-49972338fa24)
```py
ruff: disable # missing codes
```
[New example](https://play.ruff.rs/4a9970c4-3b33-4533-8ffa-f15d481b1e6f)
```py
# ruff: disable # missing codes
```
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
This fixes issue #2470 where recursive type aliases like `type
RecursiveT = int | tuple[RecursiveT, ...]` caused a stack overflow when
used in return type checking with constructors like `list()`.
The fix moves all type mapping processing for `UniqueSpecialization`
(and other non-EagerExpansion mappings) inside the `visitor.visit()`
closure. This ensures that if we encounter the same TypeAlias
recursively during type mapping, the cycle detector will properly detect
it and return the fallback value instead of recursing infinitely.
The key insight is that the previous code called
`apply_function_specialization` followed by another
`apply_type_mapping_impl` AFTER the visitor closure returned. At that
point, the TypeAlias was no longer in the visitor's `seen` set, so
recursive references would not be detected as cycles.
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## Summary
The test I've added illustrates the fix. Copying it here too:
```python
from contextlib import contextmanager
from typing import Iterator
from typing_extensions import Self
class Base:
@classmethod
@contextmanager
def create(cls) -> Iterator[Self]:
yield cls()
class Child(Base): ...
with Base.create() as base:
reveal_type(base) # revealed: Base (after the fix, None before)
with Child.create() as child:
reveal_type(child) # revealed: Child (after the fix, None before)
```
Full disclosure: I've used LLMs for this PR, but the result is
thoroughly reviewed by me before submitting. I'm excited about my first
Rust contribution to Astral tools and will address feedback quickly.
Related to https://github.com/astral-sh/ty/issues/2030, I am working on
a fix for the TypeVar case also reported in that issue (by me)
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
<!-- How was it tested? -->
Updated mdtests
---------
Co-authored-by: Douglas Creager <dcreager@dcreager.net>
## Summary
I didn't want to make the "dynamic" `type(...)` PR any larger, but it
probably makes sense to rename these now that we have `Dynamic`
variants.
Fixes https://github.com/astral-sh/ty/issues/2467
When calling a method on an instance of a generic class with bounded
type parameters (e.g., `C[T: K]` where `K` is a NewType), ty was
incorrectly reporting: "Argument type `C[K]` does not satisfy upper
bound `C[T@C]` of type variable `Self`"
The issue was introduced by PR #22105, which moved the catch-all case
for NewType assignments that falls back to the concrete base type. This
case was moved before the TypeVar handling cases, so when checking `K <:
T@C` (where K is a NewType and T@C is a TypeVar with upper bound K):
1. The NewType fallback matched first
2. It delegated to `int` (K's concrete base type)
3. Then checked `int <: T@C`, which checks if `int` satisfies bound `K`
4. But `int` is not assignable to `K` (NewTypes are distinct from their
bases)
The fix moves the NewType fallback case after the TypeVar cases, so
TypeVar handling takes precedence. Now when checking `K <: T@C`, we use
the TypeVar case at line 828 which returns `false` for non-inferable
typevars - but this is correct because the *other* direction (`T@C <:
K`) passes, and for the overall specialization comparison both
directions are checked.
## Summary
This PR adds support for dynamic classes created via `type()`. The core
of the change is that `ClassLiteral` is now an enum:
```rust
pub enum ClassLiteral<'db> {
/// A class defined via a `class` statement.
Stmt(StmtClassLiteral<'db>),
/// A class created via the functional form `type(name, bases, dict)`.
Functional(FunctionalClassLiteral<'db>),
}
```
And, in turn, various methods on `ClassLiteral` like `body_scope` now
return `Option` or similar (and callers must adjust to that change in
signature).
Over time, we can expand the enum to include functional namedtuples,
etc. (I already have this working in a separate branch, and I believe it
slots in well.)
(I'd love help with the names -- I think `StmtClassLiteral` is kind of
lame. Maybe `DeclarativeClassLiteral`?)
Closes https://github.com/astral-sh/ty/issues/740.
---------
Co-authored-by: Alex Waygood <alex.waygood@gmail.com>
## Summary
The type inference system already correctly special-cases `__file__` to
return `str` for the current module (since the code is executing from an
existing file). However, the completion system was bypassing this logic
and pulling `__file__: str | None` directly from `types.ModuleType` in
typeshed.
This PR adds implicit module globals (like `__file__`, `__name__`, etc.)
with their correctly-typed values to completions, reusing the existing
`module_type_implicit_global_symbol` function that already handles the
special-casing.
Closes https://github.com/astral-sh/ty/issues/2445.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
Like `ProtocolInstance`, we now use `left.cmp(right)` by deriving
`PartialOrd` and `Ord`. IIUC, this uses Salsa ID for Salsa-interned
types, but avoids `None.cmp(None)` for synthesized variants.
Closes https://github.com/astral-sh/ty/issues/2451.
## Summary
Correctly handle upper bounds for contravariant type variables during
specialization inference. Previously, the type checker incorrectly
applied covariant subtyping rules, requiring the actual type to directly
satisfy the bound rather than checking for a valid intersection.
In contravariant positions, subtyping relationships are inverted. The
bug caused valid code like `f(x: Contra[str])` where `f` expects
`Contra[T: int]` to be incorrectly rejected, when it should solve `T` to
`Never` (the intersection of `int` and `str`).
Closes https://github.com/astral-sh/ty/issues/2427
## Details
- Added `is_contravariant()` helper to `TypeVarVariance` in
`variance.rs`
- Updated `SpecializationBuilder::infer_map_impl` in `generics.rs` to
treat bounds and constraints differently based on variance:
* Skip immediate `ty <: bound` check for contravariant upper bounds
* Flip constraint check to `constraint <: ty` for contravariant
positions
- Added test case for bounded contravariant type variables in
`variance.md`
- All 308 mdtest cases pass & 150 ty_python_semantic unit tests pass
---------
Co-authored-by: Douglas Creager <dcreager@dcreager.net>
## Summary
prek allows you to set priorities, and can run tasks of the same
priority concurrently (e.g., we can run Ruff's Python formatting and
`cargo fmt` at the same time). On my machine, this takes `uvx prek run
-a` from 19.4s to 5.0s (~a 4x speed-up).
This PR adjusts the logic for skipping formatting so that a `fmt: skip`
can affect multiple statements if they lie on the same line.
Specifically, a `fmt: skip` comment will now suppress all the statements
in the suite in which it appears whose range intersects the line
containing the skip directive. For example:
```python
x=[
'1'
];x=2 # fmt: skip
```
remains unchanged after formatting.
(Note that compound statements are somewhat special and were handled in
a previous PR - see #20633).
Closes#17331 and #11430.
Simplest to review commit by commit - the key diffs of interest are the
commit introducing the core logic, and the diff between the snapshots
introduced in the last commit (compared to the second commit).
# Implementation
On `main` we format a suite of statements by iterating through them. If
we meet a statement with a leading or trailing (own-line)`fmt: off`
comment, then we suppress formatting until we meet a `fmt: on` comment.
Otherwise we format the statement using its own formatting rule.
How are `fmt: skip` comments handled then? They are handled internally
to the formatting of each statement. Specifically, calling `.fmt` on a
statement node will first check to see if there is a trailing,
end-of-line `fmt: skip` (or `fmt: off`/`yapf: off`), and if so then
write the node with suppressed formatting.
In this PR we move the responsibility for handling `fmt: skip` into the
formatting logic of the suite itself. This is done as follows:
- Before beginning to format the suite, we do a pass through the
statements and collect the data of ranges with skipped formatting. More
specifically, we create a map with key given by the _first_ skipped
statement in a block and value a pair consisting of the _last_ skipped
statement and the _range_ to write verbatim.
- We iterate as before, but if we meet a statement that is a key in the
map constructed above, we pause to write the associated range verbatim.
We then advance the iterator to the last statement in the block and
proceed as before.
## Addendum on range formatting
We also had to make some changes to range formatting in order to support
this new behavior. For example, we want to make sure that
```python
<RANGE_START>x=1<RANGE_END>;x=2 # fmt: skip
```
formats verbatim, rather than becoming
```python
x = 1;x=2 # fmt: skip
```
Recall that range formatting proceeds in two steps:
1. Find the smallest enclosing node containing the range AND that has
enough info to format the range (so it may be larger than you think,
e.g. a docstring has enclosing node given by the suite, not the string
itself.)
2. Carve out the formatted range from the result of formatting that
enclosing node.
We had to modify (1), since the suite knows how to format skipped nodes,
but nodes may not "know" they are skipped. To do this we altered the
`visit_body` bethod of the `FindEnclosingNode` visitor: now we iterate
through the statements and check for skipped ranges intersecting the
format range. If we find them, we return without descending. The result
is to consider the statement containing the suite as the enclosing node
in this case.
## Summary
If parent violates LSP against grandparent, and child has the same
violation (but matches parent), we no longer flag the LSP violation on
child, since it can't be fixed without violating parent.
If parent violates LSP against grandparent, and child violates LSP
against both parent and grandparent, we emit two diagnostics (one for
each violation).
If parent violates LSP against grandparent, and child violates LSP
against parent (but not grandparent), we flag it.
Closes https://github.com/astral-sh/ty/issues/2000.
## Summary
Ruff's `--fix` for `RUF100` can inadvertently remove trailing comments
(e.g., `pylint` or `mypy` suppressions) by interpreting them as
descriptions. This PR adds a "Conflict with other linters" section to
the rule documentation to clarify this behavior and provide the
double-hash (`# noqa # pylint`) workaround.
## Fixes
Fixes#20762
This makes it so, e.g., `os<CURSOR>` will suggest the top-level stdlib
`os` module even if there is an `os` symbol elsewhere in your project.
The way this is done is somewhat overwrought, but it's done to avoid
suggesting top-level modules over other symbols already in scope.
Fixesastral-sh/issues#1852
Part of this was already done, but it was half-assed. We now look at the
search path that a symbol came from and centralize a symbol's origin
classification.
The preference ordering here is maybe not the right one, but we can
iterate as users give us feedback. Note also that the preference
ordering based on the origin is pretty low in the relevance sorting.
This means that other more specific criteria will and can override this.
This results in some nice improvements to our evaluation tasks.
This commit adds two new tests. One checks that a symbol in the current
project gets priority over a symbol in the standard library. Another
checks that a symbol in a third party dependency gets priority over a
symbol in the standard library. We don't get either of these right
today.
Note that these comparisons are done ceteris paribus. A symbol from the
standard library could still be ranked above a symbol elsewhere.
(Although I believe currently this is somewhat rare.)
I apparently don't know how to use my own API. Previously,
we would skip, e.g., `.venv`, but still descend into it.
This was annoying in practice because I sometimes have an
environment in one of the truth task directories. The eval
command should ignore that entirely, but it ended up
choking on it without properly ignoring hidden files
and directories.
Previously, we would only sort by name and file path (unless the symbol
refers to an entire module). This led to somewhat confusing ordering,
since the file path is absolute and can be anything.
Sorting by module name after symbol name gives a more predictable
ordering in common practice.
This is mostly just an improvement for debugging purposes, i.e., when
looking at the output of `all_symbols` directly. This mostly shouldn't
impact completion ordering since completions do their own ranking.
This moves the information we want to use to rank completions into
`Completion` itself. (This was the primary motivation for creating a
`CompletionBuilder` in the first place.)
The principal advantage here is that we now only need to compute the
relevance information for each completion exactly once. Previously, we
were computing it on every comparison, which might end up doing
redundant work for a not insignifcant number of completions.
The relevance information is also specifically constructed from the
builder so that, in the future, we might choose to short-circuit
construction if we know we'll never send it back to the client (e.g.,
its ranking is worse than the lowest ranked completion). But we don't
implement that optimization yet.
I want to be able to attach extra data to each `Completion`, but not
burden callers with the need to construct it. This commit helps get us
to that point by requiring callers to use a `CompletionBuilder` for
construction instead of a `Completion` itself.
I think this will also help in the future if it proves to be the case
that we can improve performance by delaying work until we actually build
a `Completion`, which might only happen if we know we won't throw it
out. But we aren't quite there yet.
This also lets us tighten things up a little bit and makes completion
construction less noisy. The downside is that callers no longer need to
consider "every" completion field.
There should not be any behavior changes here.
I went through https://github.com/astral-sh/ty/issues/1274 and tried to
extract what I could into eval tasks. Some of the suggestions from that
issue have already been done, but most haven't.
This captures the status quo.
This TODO is very old -- we have long since recorded this definition.
Updating the test to actually assert the declaration requires a new
helper method for declarations, to complement the existing
`first_public_binding` helper.
---------
Co-authored-by: Claude <noreply@anthropic.com>
When working with constraint sets, we track transitive relationships
between the constraints in the set. For instance, in `S ≤ int ∧ int ≤
T`, we can infer that `S ≤ T`. However, we should only consider fully
static types when looking for a "pivot" for this kind of transitive
relationship. The same pattern does not hold for `S ≤ Any ∧ Any ≤ T`;
because the two `Any`s can materialize to different types, we cannot
infer that `S ≤ T`.
Fixes https://github.com/astral-sh/ty/issues/2371
Resolves#21892
## Summary
This PR updates `docs/editors/features.md` to clarify that Jupyter
Notebooks are now included by default as of version 0.6.0.
## Summary
Updates the fix title for RUF102 to either specify which rule code to
remove, or clarify
that the entire suppression comment should be removed.
## Test Plan
Updated test snapshots.
## Summary
This PR fixes `super()` handling when the first parameter (`self` or
`cls`) is annotated with a TypeVar, like `Self`.
Previously, `super()` would incorrectly resolve TypeVars to their bounds
before creating the `BoundSuperType`. So if you had `self: Self` where
`Self` is bounded by `Parent`, we'd process `Parent` as a
`NominalInstance` and end up with `SuperOwnerKind::Instance(Parent)`.
As a result:
```python
class Parent:
@classmethod
def create(cls) -> Self:
return cls()
class Child(Parent):
@classmethod
def create(cls) -> Self:
return super().create() # Error: Argument type `Self@create` does not satisfy upper bound `Parent`
```
We now track two additional variants on `SuperOwnerKind` for TypeVar
owners:
- `InstanceTypeVar`: for instance methods where self is a TypeVar (e.g.,
`self: Self`).
- `ClassTypeVar`: for classmethods where `cls` is a `TypeVar` wrapped in
`type[...]` (e.g., `cls: type[Self]`).
Closes https://github.com/astral-sh/ty/issues/2122.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
We enabled [`CompletionListisIncomplete`] in our LSP server a while back
in order to have more of a say in how we rank and filter completions.
When it isn't set, the client tends to ask for completions less
frequently and will instead do its own filtering.
But... we did not enable it for the playground. Which I guess didn't
result in anything noticeably bad until we started limiting completions
to 1,000 suggestions. This meant that if the _initial_ completion
response didn't include the ultimate desired answer, then it would never
show up in the results until the client requested completions again.
This in turn led to some very poor completions in some cases.
This all gets fixed by simply enabling `isIncomplete` for Monaco.
Fixesastral-sh/ty#2340
[`CompletionList::isIncomplete`](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#completionList)
## Summary
Fixes https://github.com/astral-sh/ty/issues/2363
Fixes https://github.com/astral-sh/ty/issues/2013
And several other bugs with the same root cause. And makes any similar
bugs impossible by construction.
Previously we distinguished "no annotation" (Rust `None`) from
"explicitly annotated with something of type `Unknown`" (which is not an
error, and results in the annotation being of Rust type
`Some(Type::DynamicType(Unknown))`), even though semantically these
should be treated the same.
This was a bit of a bug magnet, because it was easy to forget to make
this `None` -> `Unknown` translation everywhere we needed to. And in
fact we did fail to do it in the case of materializing a callable,
leading to a top-materialized callable still having (rust) `None` return
type, which should have instead materialized to `object`.
This also fixes several other bugs related to not handling un-annotated
return types correctly:
1. We previously considered the return type of an unannotated `async
def` to be `Unknown`, where it should be `CoroutineType[Any, Any,
Unknown]`.
2. We previously failed to infer a ParamSpec if the return type of the
callable we are inferring against was not annotated.
3. We previously wrongly returned `Unknown` from `some_dict.get("key",
None)` if the value type of `some_dict` included a callable type with
un-annotated return type.
We now make signature return types and annotated parameter types
required, and we eagerly insert `Unknown` if there's no annotation. Most
of the diff is just a bunch of mechanical code changes where we
construct these types, and simplifications where we use them.
One exception is type display: when a callable type has un-annotated
parameters, we want to display them as un-annotated, but if it has a
parameter explicitly annotated with something of `Unknown` type, we want
to display that parameter as `x: Unknown` (it would be confusing if it
looked like your annotation just disappeared entirely).
Fortunately, we already have a mechanism in place for handling this: the
`inferred_annotation` flag, which suppresses display of an annotation.
Previously we used it only for `self` and `cls` parameters with an
inferred annotated type -- but we now also set it for any un-annotated
parameter, for which we infer `Unknown` type.
We also need to normalize `inferred_annotation`, since it's display-only
and shouldn't impact type equivalence. (This is technically a
previously-existing bug, it just never came up when it only affected
self types -- now it comes up because we have tests asserting that `def
f(x)` and `def g(x: Unknown)` are equivalent.)
## Test Plan
Added mdtests.
## 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).
## Summary
fixes: https://github.com/astral-sh/ty/issues/2027
This PR fixes a bug where the type mapping for a `ParamSpec` was not
being applied in an overloaded function.
This PR also fixes https://github.com/astral-sh/ty/issues/2081 and
reveals new diagnostics which doesn't look related to the bug:
```py
from prefect import flow, task
@task
def task_get() -> int:
"""Task get integer."""
return 42
@task
def task_add(x: int, y: int) -> int:
"""Task add two integers."""
print(f"Adding {x} and {y}")
return x + y
@flow
def my_flow():
"""My flow."""
x = 23
future_y = task_get.submit()
# error: [no-matching-overload]
task_add(future_y, future_y)
# error: [no-matching-overload]
task_add(x, future_y)
```
The reason is that the type of `future_y` is `PrefectFuture[int]` while
the type of `task_add` is `Task[(x: int, y: int), int]` which means that
the assignment between `int` and `PrefectFuture[int]` fails which
results in no overload matching. Pyright also raises the invalid
argument type error on all three usages of `future_y` in those two
calls.
## Test Plan
Add regression mdtest from the linked issue.
@dhruvmanila encountered this in #22416 — there are two different
`TypeMapping` variants for apply a specialization to a type. One
operates on a full `Specialization` instance, the other on a partially
constructed one. If we move this enum-ness "down a level" it reduces
some copy/paste in places where we are operating on a `TypeMapping`.
## Summary
Combines diagnostics for matched suppression comments, so that ranges
and autofixes for both
the `#ruff:disable` and `#ruff:enable` comments will be reported as a
single diagnostic.
## Test Plan
Snapshot changes, added new snapshot for full output from preview mode
rather than just a diff.
Issue #3711
## Summary
Fixes https://github.com/astral-sh/ty/issues/2292
When solving a bounded typevar, we preferred the upper bound over the
actual type seen in the call. This change fixes that.
## Test Plan
Added mdtest, existing tests pass.
By stripping leading indents from codefence lines to ensure they're
properly understood by markdown (but otherwise preserving the indent in
the codeblock so all the code renders roughly at the right indent).
As described in [this
comment](https://github.com/astral-sh/ty/issues/2352#issuecomment-3711686053)
this solution is very "do what I mean" for when a user has an explicit
markdown codeblock in e.g. a `Returns:` section which "has" to be
indented but that indent makes the verbatim codefence invalid markdown.
* Fixes https://github.com/astral-sh/ty/issues/2352
I am updating these because we didn't have test coverage for the
different handling of `fmt: skip` comments applied to multiple
statements on the same line. This is in preparation for #22119 (to show
before/after deviations).
Follows the same procedure as in #20794
Edit: As it happens, the new fixtures do not even cover the case
relevant to #22119 - they just deal with the already handled case of a
one-line compound statement. Nevertheless, it seems worthwhile to make
this update, especially since it uncovered a (possible?) bug.
## Summary
This raises a `ValueError` at runtime:
```python
from functools import total_ordering
@total_ordering
class NoOrdering:
def __eq__(self, other: object) -> bool:
return True
```
Specifically:
```
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/functools.py", line 193, in total_ordering
raise ValueError('must define at least one ordering operation: < > <= >=')
ValueError: must define at least one ordering operation: < > <= >=
```
See: https://github.com/astral-sh/ty/issues/1202.
Summary
--
Closes#17091. `PLW1510` checks for `subprocess.run` calls without a
`check`
keyword argument and previously had a safe fix to add `check=False`.
That's the
default value, so technically it preserved the code's behavior, but as
discussed
in #17091 and #17087, Ruff can't actually know what the author intended.
I don't think it hurts to keep this as a display-only fix instead of
removing it
entirely, but it definitely shouldn't be safe at the very least.
Test Plan
--
Existing tests
`logging.basicConfig` should not be called at a global module scope,
as that produces a race condition to configure logging based on which
module gets imported first. Logging should instead be initialized
in an entrypoint to the program, either in a `main()` or in the
typical `if __name__ == "__main__"` block.
## Summary
We use this profile in uv to create success, as an optimization for the
iterative test loop. We include `opt-level=1` because it ends up being
"worth it" for testing (empirically), even though it means the build is
actually a big slower than `dev` (if you remove `opt-level=1`, clean
compile is about 22% faster than `dev`).
Here are some benchmarks I generated with Claude -- the main motivator
here is the incremental testing for `ty_python_semantic` which is 2.4x
faster:
### `ty_python_semantic`
Full test suite (471 tests):
| Scenario | dev | fast-test | Improvement |
|-------------|-------|------------|-------------|
| Clean | 53s | 49s | 8% faster |
| Incremental | 17.8s | 6.8s | 2.4x faster |
Single test:
| Scenario | dev | fast-test | Improvement |
|-------------|-------|------------|-------------|
| Clean | 42.5s | 55.3s | 30% slower |
| Incremental | 6.5s | 6.1s | ~same |
### `ruff_linter`
Full test suite (2622 tests):
| Scenario | dev | fast-test | Improvement |
|-------------|-------|------------|-------------|
| Clean | 31s | 41s | 32% slower |
| Incremental | 11.9s | 10.5s | 12% faster |
Single test:
| Scenario | dev | fast-test | Improvement |
|-------------|------|------------|-------------|
| Clean | 26s | 36.5s | 40% slower |
| Incremental | 4.5s | 5.5s | 22% slower |
Snapshot tests recently started reporting this warning:
> Snapshot test passes but the existing value is in a legacy format.
> Please run cargo insta test --force-update-snapshots to update to a
> newer format.
This PR is the result of that forced update.
One file (crates/ruff_db/src/diagnostic/render/full.rs) seems to get
corrupted, because it contains strings with unprintable characters that
trigger some bug in cargo-insta. I've manually reverted that file, and
also manually reverted the `input_file:` lines, which we like.
## Summary
Decorators are now called with the class as an argument, and the return
type becomes the class's type. This mirrors how function decorators
already work.
Closes https://github.com/astral-sh/ty/issues/2313.
## Summary
This PR closes#21692. `PLR1714` will no longer flag if all members are
identical. I iterate through the equality comparisons and if they are
all equal the rule does not flag.
## Test Plan
Additional tests were added with identical members.
Summary
--
This PR fixes#14900 by:
- Restricting the diagnostic range from the whole `for` loop to only the
`target in iter` part
- Adding secondary annotations to each use of the `dict[key]` accesses
- Adding a `fix_title` suggesting to use `for key in dict.items()`
I thought this approach sounded slightly nicer than the alternative of
renaming the rule to focus on each indexing operation mentioned in
https://github.com/astral-sh/ruff/issues/14900#issuecomment-2543923625,
but I don't feel too strongly. This was easy to implement with our new
diagnostic infrastructure too.
This produces an example annotation like this:
```
PLC0206 Extracting value from dictionary without calling `.items()`
--> dict_index_missing_items.py:59:5
|
58 | # A case with multiple uses of the value to show off the secondary annotations
59 | for instrument in ORCHESTRA:
| ^^^^^^^^^^^^^^^^^^^^^^^
60 | data = json.dumps(
61 | {
62 | "instrument": instrument,
63 | "section": ORCHESTRA[instrument],
| ---------------------
64 | }
65 | )
66 |
67 | print(f"saving data for {instrument} in {ORCHESTRA[instrument]}")
| ---------------------
68 |
69 | with open(f"{instrument}/{ORCHESTRA[instrument]}.txt", "w") as f:
| ---------------------
70 | f.write(data)
|
help: Use `for instrument, value in ORCHESTRA.items()` instead
```
which I think is a big improvement over:
```
PLC0206 Extracting value from dictionary without calling `.items()`
--> dict_index_missing_items.py:59:1
|
58 | # A case with multiple uses of the value to show off the secondary annotations
59 | / for instrument in ORCHESTRA:
60 | | data = json.dumps(
61 | | {
62 | | "instrument": instrument,
63 | | "section": ORCHESTRA[instrument],
64 | | }
65 | | )
66 | |
67 | | print(f"saving data for {instrument} in {ORCHESTRA[instrument]}")
68 | |
69 | | with open(f"{instrument}/{ORCHESTRA[instrument]}.txt", "w") as f:
70 | | f.write(data)
| |_____________________^
|
```
The secondary annotation feels a bit bare without a message, but I
thought it
might be too busy to include one. Something like `value extracted here`
or
`indexed here` might work if we do want to include a brief message.
To avoid collecting a `Vec` of annotation ranges, I added a `&Checker`
to the
rule's visitor to emit diagnostics as we go instead of at the end.
Test Plan
--
Existing tests, plus a new case showing off multiple secondary
annotations
## Summary
Fixes false positive in ARG001 when `**kwargs` is passed to
`typing.TypeVar`
Closes#22178
When `**kwargs` is used in a `typing.TypeVar` call, the checker was not
recognizing it as a usage, leading to false positive "unused function
argument" warnings.
### Root Cause
In the AST, keyword arguments are represented by the `Keyword` struct
with an `arg` field of type `Option<Identifier>`:
- Named keywords like `bound=int` have `arg = Some("bound")`
- Dictionary unpacking like `**kwargs` has `arg = None`
The existing code only handled the `Some(id)` case, never visiting the
expression when `arg` was `None`, so `**kwargs` was never marked as
used.
### Changes
Added an `else` branch to handle `**kwargs` unpacking by calling
`visit_non_type_definition(value)` when `arg` is `None`. This ensures
the `kwargs` variable is properly visited and marked as used by the
semantic model.
## Test Plan
Tested with the following code:
```python
import typing
def f(
*args: object,
default: object = None,
**kwargs: object,
) -> None:
typing.TypeVar(*args, **kwargs)
```
Before :
`ARG001 Unused function argument: kwargs
`
After :
`All checks passed!`
Run the example with the following command(from the root of ruff and
please change the path to the module that contains the code example):
`cargo run -p ruff -- check /path/to/file.py --isolated --select=ARG
--no-cache`
## Summary
This is a follow up PR to https://github.com/astral-sh/ruff/pull/21096
The new code AIR303 is added for checking function signature change in
Airflow 3.0. The new rule added to AIR303 will check if positional
argument is passed into
`airflow.lineage.hook.HookLineageCollector.create_asset`. Since this
method is updated to accept only keywords argument, passing positional
argument into it is not allowed, and will raise an error. The test is
done by checking whether positional argument with 0 index can be found.
## Test Plan
A new test file is added to the fixtures for the code AIR303. Snapshot
test is updated accordingly.
<img width="1444" height="513" alt="Screenshot from 2025-12-17 20-54-48"
src="https://github.com/user-attachments/assets/bc235195-e986-4743-9bf7-bba65805fb87"
/>
<img width="981" height="433" alt="Screenshot from 2025-12-17 21-34-29"
src="https://github.com/user-attachments/assets/492db71f-58f2-40ba-ad2f-f74852fa5a6b"
/>
Summary
--
This PR adds a new rule, `non-empty-init-module`, which restricts the
kind of
code that can be included in an `__init__.py` file. By default,
docstrings,
imports, and assignments to `__all__` are allowed. When the new
configuration
option `lint.ruff.strictly-empty-init-modules` is enabled, no code at
all is
allowed.
This closes#9848, where these two variants correspond to different
rules in the
[`flake8-empty-init-modules`](https://github.com/samueljsb/flake8-empty-init-modules/)
linter. The upstream rules are EIM001, which bans all code, and EIM002,
which
bans non-import/docstring/`__all__` code. Since we discussed folding
these into
one rule on [Discord], I just added the rule to the `RUF` group instead
of
adding a new `EIM` plugin.
I'm not really sure we need to flag docstrings even when the strict
setting is
enabled, but I just followed upstream for now. Similarly, as I noted in
a TODO
comment, we could also allow more statements involving `__all__`, such
as
`__all__.append(...)` or `__all__.extend(...)`. The current version only
allows
assignments, like upstream, as well as annotated and augmented
assignments,
unlike upstream.
I think when we discussed this previously, we considered flagging the
module
itself as containing code, but for now I followed the upstream
implementation of
flagging each statement in the module that breaks the rule (actually the
upstream linter flags each _line_, including comments). This will
obviously be a
bit noisier, emitting many diagnostics for the same module. But this
also seems
preferable because it flags every statement that needs to be fixed up
front
instead of only emitting one diagnostic for the whole file that persists
as you
keep removing more lines. It was also easy to implement in
`analyze::statement`
without a separate visitor.
The first commit adds the rule and baseline tests, the second commit
adds the
option and a diff test showing the additional diagnostics when the
setting is
enabled.
I noticed a small (~2%) performance regression on our largest benchmark,
so I also added a cached `Checker::in_init_module` field and method
instead of the `Checker::path` method. This was almost the only reason
for the `Checker::path` field at all, but there's one remaining
reference in a `warn_user!`
[call](https://github.com/astral-sh/ruff/blob/main/crates/ruff_linter/src/checkers/ast/analyze/definitions.rs#L188).
Test Plan
--
New tests adapted from the upstream linter
## Ecosystem Report
I've spot-checked the ecosystem report, and the results look "correct."
This is obviously a very noisy rule if you do include code in
`__init__.py` files. We could make it less noisy by adding more
exceptions (e.g. allowing `if TYPE_CHECKING` blocks, allowing
`__getattr__` functions, allowing imports from `importlib` assignments),
but I'm sort of inclined just to start simple and see what users need.
[Discord]:
https://discord.com/channels/1039017663004942429/1082324250112823306/1440086001035771985
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
Summary
--
This is a follow up to #22198 documenting more rule options I found
while going
through all of our rules.
The second commit renames the internal
`flake8_gettext::Settings::functions_names` field to `function_names` to
match
the external configuration option. I guess this is technically breaking
because
it's exposed to users via `--show-settings`, but I don't think we
consider that
part of our stable API. I can definitely revert that if needed, though.
The other changes are just like #22198, adding new `## Options` sections
to
rules to document the settings they use. I missed these in the previous
PR
because they were used outside the rule implementations themselves. Most
of
these settings are checked where the rules' implementation functions are
called
instead.
Oh, the last commit also updates the removal date for
`typing.ByteString`, which
got pushed back in the 3.14 release. I snuck that in today since I never
opened
this PR last week.
I also fixed one reference link in RUF041.
Test Plan
--
Docs checks in CI
## Summary
As-is, the following rejects `return self.value` in `def other` in the
subclass
([link](https://play.ty.dev/f55b47b2-313e-45d1-ba45-fde410bed32e))
because `self.value` is resolving to `Unknown | int | float | property`:
```python
class Base:
_value: float = 0.0
@property
def value(self) -> float:
return self._value
@value.setter
def value(self, v: float) -> None:
self._value = v
@property
def other(self) -> float:
return self.value
@other.setter
def other(self, v: float) -> None:
self.value = v
class Derived(Base):
@property
def other(self) -> float:
return self.value
@other.setter
def other(self, v: float) -> None:
reveal_type(self.value) # revealed: int | float
self.value = v
```
I believe the root cause is that we're not excluding properties when
searching for class methods, so we're treating the `other` setter as a
classmethod. I don't fully understand how that ends up materializing as
`| property` on the union though.
## Summary
If we match on an `TestEnum | None`, then when adding a case like
`~Literal[TestEnum.FOO]` (i.e., after `if value == TestEnum.FOO:
return`), we'd distribute `Literal[TestEnum.BAR]` on the entire builder,
creating `None & Literal[TestEnum.BAR]` which simplified to `Never`.
Instead, we should only expand to the remaining members for pieces of
the intersection that contain the enum.
Now, `(TestEnum | None) & ~Literal[TestEnum.FOO] &
~Literal[TestEnum.BAR]` correctly simplifies to `None` instead of
`Never`.
Closes https://github.com/astral-sh/ty/issues/2260.
## Summary
`apply_type_mapping` always expands type aliases and operates on the
resulting types, which can lead to cluttered results due to excessive
type alias expansion in places where it is not actually needed.
Specifically, type aliases are expanded when displaying method
signatures, because we use `TypeMapping::BindSelf` to get the method
signature.
```python
type Scalar = int | float
type Array1d = list[Scalar] | tuple[Scalar]
def f(x: Scalar | Array1d) -> None: pass
reveal_type(f) # revealed: def f(x: Scalar | Array1d) -> None
class Foo:
def f(self, x: Scalar | Array1d) -> None: pass
# should be `bound method Foo.f(x: Scalar | Array1d) -> None`
reveal_type(Foo().f) # revealed: bound method Foo.f(x: int | float | list[int | float] | tuple[int | float]) -> None
```
In this PR, when type mapping is performed on a type alias, the
expansion result without type mapping is compared with the expansion
result after type mapping, and if the two are equivalent, the expansion
is deemed redundant and canceled.
## Test Plan
mdtest updated
## Summary
Resolve(s) astral-sh/ty#117, astral-sh/ty#1569
Implement `typing.TypeGuard`. Due to the fact that it [overrides
anything previously known about the checked
value](https://typing.python.org/en/latest/spec/narrowing.html#typeguard)---
> When a conditional statement includes a call to a user-defined type
guard function, and that function returns true, the expression passed as
the first positional argument to the type guard function should be
assumed by a static type checker to take on the type specified in the
TypeGuard return type, unless and until it is further narrowed within
the conditional code block.
---we have to substantially rework the constraints system. In
particular, we make constraints represented as a disjunctive normal form
(DNF) where each term includes a regular constraint, and one or more
disjuncts with a typeguard constraint. Some test cases (including some
with more complex boolean logic) are added to `type_guards.md`.
## Test Plan
- update existing tests
- add new tests for more complex boolean logic with `TypeGuard`
- add new tests for `TypeGuard` variance
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
I only noticed this in the ecosystem report of
https://github.com/astral-sh/ruff/pull/22213 after merging it. The
change to displaying `Top[]` wrapper around the entire signature instead
of just the parameters had the side effect of not showing it at all when
displaying a top ParamSpec specialization. This PR fixes that.
Marking internal since this is a fixup of a not-released PR.
## Test Plan
Added mdtest that fails without this PR.
## Summary
A couple things I noticed when taking another look at the callable type
materializations.
1) Previously we wrongly ignored the return type when
bottom-materializing a callable with gradual signature, and always
changed it to `Never`.
2) We weren't correctly handling overloads that included a gradual
signature. Rather than separately materializing each overload, we would
just mark the entire callable as "top" or replace the entire callable
with the bottom signature.
Really, "top parameters" is something that belongs on the `Parameters`,
not on the entire `CallableType`. Conveniently, we already have
`ParametersKind` where we can track this, right next to where we already
track `ParametersKind::Gradual`. This saves a bit of memory, fixes the
two bugs above, and simplifies the implementation considerably (net
removal of 100+ LOC, a bunch of places that shouldn't need to care about
topness of a callable no longer need to.)
One user-visible change from this is that I now display the "top
callable" as `(Top[...]) -> object` instead of `Top[(...) -> object]`. I
think this is a (minor) improvement, because it wraps exactly the part
in `Top` that needs to be, rather than misleadingly wrapping the entire
callable type, including the return type (which has already been
separately materialized). I think the prior display would be
particularly confusing if the return type also has its own `Top` in it:
previously we could have e.g. `Top[(...) -> Top[list[Unknown]]]`, which
I think is less clear than the new `(Top[...]) -> Top[list[Unknown]]`.
## Test Plan
Added mdtests that failed before this PR and pass after it.
### Ecosystem
The changed diagnostics are all either the change to `Top` display, or
else known non-deterministic output. The added diagnostics are all true
positives:
The added diagnostic at
aa35ca1965/torchvision/transforms/v2/_utils.py (L149)
is a true positive that wasn't caught by the previous version. `str` is
not assignable to `Callable[[Any], Any]` (strings are not callable), nor
is the top callable (top callable includes callables that do not take a
single required positional argument.)
The added diagnostic at
081535ad9b/starlette/routing.py (L67)
is also a (pedantic) true positive. It's the same case as #1567 -- the
code assumes that it is impossible for a subclass of `Response` to
implement `__await__` (yielding something other than a `Response`).
The pytest added diagnostics are also both similar true positives: they
make the assumption that an object cannot simultaneously be a `Sequence`
and callable, or an `Iterable` and callable.
## Summary
Resolve https://github.com/astral-sh/ty/issues/2226
We need to add a special case in `apply_type_mapping` instead of
directly in `promote_literals_impl` because we do not reach this with
non generic non tuple nominal instances. We still ensure we apply the
normal mapping if we do not see `float` or `complex` instances.
## Test Plan
Update existing mdtest and add a new case to `literal_promotion.md`
Summary
--
Noticed while responding to #22201 that the last sentence here just ends
abruptly. It turns out that I missed this change when reviewing #21382.
Test Plan
--
CI
Summary
--
While analyzing our rules, I wanted to know which of them use
configuration options but noticed that some of them were not documented
(or at least not documented in a separate `## Options` section).
I had Claude generate an initial list of candidate rules, but it
contained a lot of false positives that I filtered out, and I ended up
adding all of these sections myself. I'm not claiming that the options
lists are exhaustive (as in the rules may use additional options beyond
what I found), but this will at least help with my goal of determining
whether or not a rule is configurable at all and also hopefully be
helpful in general.
I mostly just tacked on an `## Options` section without any commentary,
but I added a couple lines of explanation when I felt that the meaning
of the options wasn't obvious from the context.
I also noticed a bit of variation in the `flake8-simplify` rules from
doing this. Some of them offer a diagnostic but no fix depending on the
resulting line length of the suggestion, while others offer neither. I'm
not sure we need to do anything different here, but it seemed worth
mentioning.
Test Plan
--
Docs tests to make sure the links are right
## Summary
This PR reworks our ecosystem-analyzer workflow so that it automatically
reruns if a PR with the `ecosystem-analyzer` label has new commits
pushed to it, or is reopened after previously being closed. It's
currently easy to forget that you need to remove and re-add the label to
trigger a fresh workflow run, which can then mean that there are stale
(misleading) results in the PR comment posted by the bot. It also means
that it takes longer for CI to finish than it would otherwise, because
it might be a few minutes after pushing new commits to the PR before you
remember that you also need to remove and re-add the label.
To write this PR, I consulted:
- The GitHub workflow trigger documentation:
https://docs.github.com/en/actions/reference/workflows-and-actions/events-that-trigger-workflows#pull_request
- This Stack Overflow answer:
https://stackoverflow.com/a/59588725/13990016
## Test Plan
I experimented with pushing commits to this PR and closing/reopening it,
and both of these actions triggered fresh runs of the ecosystem-analyzer
worfklow when the label was present on the PR. However, removing the
label again meant that the workflow was no longer triggered by these
actions.
## Summary
Other type checkers allow you to access all `FunctionType` attributes on
any object with a `Callable` type. ty does not, because this is
demonstrably unsound, but this is often a source of confusion for users.
And there were lots of diagnostics in the ecosystem report for
https://github.com/astral-sh/ruff/pull/22145 that were complaining that
"Object of type `(...) -> Unknown` has no attribute `__name__`", for
example.
The discrepancy between what ty does here and what other type checkers
do is discussed a bit in https://github.com/astral-sh/ty/issues/1495.
You can see that there have been lots of issues closed as duplicates of
that issue; we should probably also add an FAQ entry for it.
Anyway, this PR adds a subdiagnostic to help users out when they hit
this diagnostic. Unfortunately something I did meant that rustfmt
increased the indentation of the whole of this huge closure, so this PR
is best reviewed with the "No whitespace" option selected for viewing
the diff.
## Test Plan
Snapshot added
Summary
--
This PR fixes https://github.com/astral-sh/ty/issues/2186 by replacing
uses of
`Diagnostic::body` with [`Diagnostic::concise_message`][d]. The initial
report
was only about ty's GitHub and GitLab output formats, but I think it
makes sense
to prefer `concise_message` in the other output formats too. Ruff
currently only
sets the primary message on its diagnostics, which is why this has no
effect on
Ruff, and ty currently only supports the GitHub and GitLab formats that
used
`body`, but removing `body` should help to avoid this problem as Ruff
starts to
use more diagnostic features or ty gets new output formats.
Test Plan
--
Updated existing GitLab and GitHub CLI tests to have `reveal_type`
diagnostics
[d]:
https://github.com/astral-sh/ruff/blob/395bf106ab/crates/ruff_db/src/diagnostic/mod.rs#L185
[t]:
https://github.com/astral-sh/ruff/blob/395bf106ab/crates/ruff/tests/cli/lint.rs#L3509
## Summary
Provides a message like:
```
error[invalid-argument-type]: Cannot delete required key "name" from TypedDict `Movie`
--> test.py:15:7
|
15 | del m["name"]
| ^^^^^^
|
info: Field defined here
--> test.py:4:5
|
4 | name: str
| --------- `name` declared as required here; consider making it `NotRequired`
|
info: Only keys marked as `NotRequired` (or in a TypedDict with `total=False`) can be deleted
```
## Summary
TypedDict now synthesizes a proper `__delitem__` method that...
- ...allows deletion of `NotRequired` keys and keys in `total=False`
TypedDicts.
- ...rejects deletion of required keys (synthesizes `__delitem__(k:
Never)`).
## Summary
We already had `CallableTypeKind::ClassMethodLike` to track callables
that behave like `classmethods` (always bind the first argument). This
PR adds the symmetric `CallableTypeKind::StaticMethodLike` for callables
that behave like `staticmethods` (never bind `self`).
Closes https://github.com/astral-sh/ty/issues/2114.
## Summary
Previously, `del x[k]` incorrectly required the object to have a
`__getitem__` method. This was wrong because deletion only needs
`__delitem__`, which is independent of `__getitem__`.
Closes https://github.com/astral-sh/ty/issues/1799.
## Summary
This PR fixes https://github.com/astral-sh/ty/issues/1848.
```python
T = tuple[int, 'U']
class C(set['U']):
pass
type U = T | C
```
The reason why the fixed point iteration did not converge was because
the types stored in the implicit tuple type alias `Specialization`
changed each time.
```
1st: <class 'tuple[int, C]'>
2nd: <class 'tuple[int, tuple[int, C] | C]'>
3rd: <class 'tuple[int, tuple[int, tuple[int, C] | C] | C]'>
...
```
And this was because `UnionType::from_elements` was used when creating
union types for tuple operations, which causes type aliases inside to be
expanded.
This PR replaces these with `UnionType::from_elements_leave_aliases`.
## Test Plan
New corpus test
Identify and narrow cases like this:
```py
class Foo(TypedDict):
tag: Literal["foo"]
class Bar(TypedDict):
tag: Literal["bar"]
def _(union: Foo | Bar):
if union["tag"] == "foo":
reveal_type(union) # Foo
```
Fixes part of https://github.com/astral-sh/ty/issues/1479.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
This PR fixes https://github.com/astral-sh/ty/issues/2085.
Based on the reported code, the panicking MRE is:
```python
class Test:
def __init__(self, x: int):
self.left = x
self.right = x
def method(self):
self.left, self.right = self.right, self.left
if self.right:
self.right = self.right
```
The type inference (`implicit_attribute_inner`) for `self.right`
proceeds as follows:
```
0: Divergent(Id(6c07))
1: Unknown | int | (Divergent(Id(1c00)) & ~AlwaysFalsy)
2: Unknown | int | (Divergent(Id(6c07)) & ~AlwaysFalsy) | (Divergent(Id(1c00)) & ~AlwaysFalsy)
3: Unknown | int | (Divergent(Id(1c00)) & ~AlwaysFalsy) | (Divergent(Id(6c07)) & ~AlwaysFalsy)
4: Unknown | int | (Divergent(Id(6c07)) & ~AlwaysFalsy) | (Divergent(Id(1c00)) & ~AlwaysFalsy)
...
```
The problem is that the order of union types is not stable between
cycles. To solve this, when unioning the previous union type with the
current union type, we should use the previous type as the base and add
only the new elements in this cycle (In the current implementation, this
unioning order was reversed).
## Test Plan
New corpus test
## Summary
IIUC, tuples with a known structure (`tuple_spec`) use the standard
tuple `__eq__` which only returns `True` for other tuples, so they can
be safely excluded when disjoint from string literals or other non-tuple
types.
Closes https://github.com/astral-sh/ty/issues/2140.
## Summary
This appears to have been a copy/paste error from the list example, as
the subscript is not present in the original next/iter example only in
the case where the error case is shown. While in the specific example
code the subscript actually has no effect, it does make the example
slightly confusing.
Consider the following variations, first the example from the docs
unchanged and second the same code but not hitting the intended error
case (due to using a non-empty collection):
```console
$ python3 -c 'next(iter(range(0)))[0]'
Traceback (most recent call last):
File "<string>", line 1, in <module>
StopIteration
$ python3 -c 'next(iter(range(1)))[0]'
Traceback (most recent call last):
File "<string>", line 1, in <module>
TypeError: 'int' object is not subscriptable
```
## Test Plan
Not directly tested, however see inline snippets above.
## Summary
I missed this in https://github.com/astral-sh/ruff/pull/22062. This
avoids exponential runtime in the following snippet:
```py
class X1: ...
class X2: ...
class X3: ...
class X4: ...
class X5: ...
class X6: ...
...
def f(
x:
list[X1 | None]
| list[X2 | None]
| list[X3 | None]
| list[X4 | None]
| list[X5 | None]
| list[X6 | None]
...
):
...
def g[T](x: T) -> list[T]:
return [x]
def id[T](x: T) -> T:
return x
f(id(id(id(id(g(X64()))))))
```
Eventually I want to refactor our multi-inference infrastructure (which
is currently very brittle) to handle this implicitly, but this is a
temporary performance fix until that happens.
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## Summary
Was looking over that PR and this looked wrong.
panic introduced in #22076
## Test Plan
Before running:
```bash
cargo run -p ty check test.py --force-exclude --no-progress
```
would result in a panic
```text
thread 'main' (162713) panicked at crates/ty/src/args.rs:459:17:
internal error: entered unreachable code: Clap should make this impossible
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
```
Now it does not.
## Summary
The following snippet currently errors because we widen the inferred
type, even though `X` is covariant over `T`. If `T` was contravariant or
invariant, this would be fine, as it would lead to an assignability
error anyways.
```python
class X[T]:
def __init__(self: X[None]): ...
def pop(self) -> T:
raise NotImplementedError
# error: Argument to bound method `__init__` is incorrect: Expected `X[None]`, found `X[int | None]`
x: X[int | None] = X()
```
There are some cases where it is still helpful to prefer covariant
declared types, but this error seems hard to fix otherwise, and makes
our heuristics more consistent overall.
## Summary
Fixes https://github.com/astral-sh/ty/issues/2090. Quoting my rationale
from that issue:
> A PR that only touches code in [one of these crates] should never have
any impact on memory usage or diagnostics produced. And the comments
from the bot just lead to additional notifications which is annoying.
I _think_ I've got the syntax right here. The
[docs](https://docs.github.com/en/actions/reference/workflows-and-actions/workflow-syntax)
say:
> The order that you define paths patterns matters:
>
> - A matching negative pattern (prefixed with !) after a positive match
will exclude the path.
> - A matching positive pattern after a negative match will include the
path again.
## Test Plan
No idea? Merge it and see?
## Summary
Fixes https://github.com/astral-sh/ty/issues/1885.
It wasn't obvious to me that there was a deliberate order to the way
these rules were listed in our reference docs -- it looked like it was
_nearly_ alphabetical, but not quite. I think it's simpler if we just
list them in alphabetical order.
## Test Plan
The output from running `cargo dev generate-all` (committed as part of
this PR) looks correct!
## Summary
Currently, the proposed fix for https://docs.astral.sh/ruff/rules/print/
violates https://docs.astral.sh/ruff/rules/root-logger-call/. Thus,
let's change the proposal to make LOG015 happy as well.
## Test Plan
Test manually in a project that has both T201 and LOG015 enabled and run
them over the previous and proposed code. Is there continuous testing of
the code snippets from the docs?
## Summary
* Related to, but does not handle
https://github.com/astral-sh/ty/issues/2021
## Test Plan
I also added some snapshot tests for future work on non-standard
attribute docstrings (didn't want to highlight them if we don't
recognize them elsewhere).
## Summary
This PR implements the strategy described in
https://github.com/astral-sh/ty/issues/1871: we iterate over the
positive types, resolve them, then intersect the results.
## Summary
This should make revealed types a little nicer, as well as avoid
confusing the constraint solver in some cases (which were showing up in
https://github.com/astral-sh/ruff/pull/21930).
## Summary
Add lockfiles for all mdtests which make use of external dependencies.
When running tests normally, we use this lockfile when creating the
temporary venv using `uv sync --locked`. A new
`MDTEST_UPGRADE_LOCKFILES` environment variable is used to switch to a
mode in which those lockfiles can be updated or regenerated. When using
the Python mdtest runner, this environment variable is automatically set
(because we use this command while developing, not to simulate exactly
what happens in CI). A command-line flag is provided to opt out of this.
## Test Plan
### Using the mdtest runner
#### Adding a new test (no lockfile yet)
* Removed `attrs.lock` to simulate this
* Ran `uv run crates/ty_python_semantic/mdtest.py -e external/`. The
lockfile is generated and the test succeeds.
#### Upgrading/downgrading a dependency
* Changed pydantic requirement from `pydantic==2.12.2` to
`pydantic==2.12.5` (also tested with `2.12.0`)
* Ran `uv run crates/ty_python_semantic/mdtest.py -e external/`. The
lockfile is updated and the test succeeds.
### Using cargo
#### Adding a new test (no lockfile yet)
* Removed `attrs.lock` to simulate this
* Ran `MDTEST_EXTERNAL=1 cargo test -p ty_python_semantic --test mdtest
mdtest__external` "naively", which outputs:
> Failed to setup in-memory virtual environment with dependencies:
Lockfile not found at
'/home/shark/ruff/crates/ty_python_semantic/resources/mdtest/external/attrs.lock'.
Run with `MDTEST_UPGRADE_LOCKFILES=1` to generate it.
* Ran `MDTEST_UPGRADE_LOCKFILES=1 MDTEST_EXTERNAL=1 cargo test -p
ty_python_semantic --test mdtest mdtest__external`. The lockfile is
updated and the test succeeds.
#### Upgrading/downgrading a dependency
* Changed pydantic requirement from `pydantic==2.12.2` to
`pydantic==2.12.5` (also tested with `2.12.0`)
* Ran `MDTEST_EXTERNAL=1 cargo test -p ty_python_semantic --test mdtest
mdtest__external` "naively", which outputs a similar error message as
above.
* Ran the command suggested in the error message (`MDTEST_EXTERNAL=1
MDTEST_UPGRADE_LOCKFILES=1 cargo test -p ty_python_semantic --test
mdtest mdtest__external`). The lockfile is updated and the test
succeeds.
We're seeing a lot of nondeterminism in the ecosystem tests at the
moment, which started (or at least got worse) once `Callable` inference
landed.
This PR attempts to remove this nondeterminism. We recently
(https://github.com/astral-sh/ruff/pull/21983) added a `source_order`
field to BDD nodes, which tracks when their constraint was added to the
BDD. Since we build up constraints based on the order that they appear
in the underlying source, that gives us a stable ordering even though we
use an arbitrary salsa-derived ordering for the BDD variables.
The issue (at least for some of the flakiness) is that we add "derived"
constraints when walking a BDD tree, and those derived constraints
inherit or borrow the `source_order` of the "real" constraint that
implied them. That means we can get multiple constraints in our
specialization that all have the same `source_order`. If we're not
careful, those "tied" constraints can be ordered arbitrarily.
The fix requires ~three~ ~four~ several steps:
- When starting to construct a sequent map (the data structure that
stores the derived constraints), we first sort all of the "real"
constraints by their `source_order`. That ensures that we insert things
into the sequent map in a stable order.
- During sequent map construction, derived facts are discovered by a
deterministic process applied to constraints in a (now) stable order. So
derived facts are now also inserted in a stable order.
- We update the fields of `SequentMap` to use `FxOrderSet` instead of
`FxHashSet`, so that we retain that stable insertion order.
- When walking BDD paths when constructing a specialization, we were
already sorting the constraints by their `source_order`. However, we
were not considering that we might get derived constraints, and
therefore constraints with "ties". Because of that, we need to make sure
to use a _stable_ sort, that retains the insertion order for those ties.
All together, this...should...fix the nondeterminism. (Unfortunately, I
haven't been able to effectively test this, since I haven't been able to
coerce local tests to flop into the other order that we sometimes see in
CI.)
## Summary
- Adds new RUF103 and RUF104 diagnostics for invalid and unmatched
suppression comments
- Reports RUF100 for any unused range suppression
- Reports RUF102 for range suppression comment with invalid rule codes
- Reports RUF103 for range suppression comment with invalid suppression syntax
- Reports RUF104 diagnostics for any unmatched range suppression comment (disable w/o enable)
## Test Plan
Updated snapshots from test cases with unmatched suppression comments
Issue #3711Fixes#21878Fixes#21875
@carljm put forth a reasonably compelling argument that just disabling
this lint might be advisable. If we agree, here's the implementation.
* Fixes https://github.com/astral-sh/ty/issues/309
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
There are cases where the python grammar enforces expressions
after certain statements. In such cases we want to suppress
irrelevant keywords from the auto-complete suggestions.
E.g. `with a<CURSOR>`, suggesting `raise` here never makes sense
because it is not valid by the grammar.
This refactor is intended to give more structure to how we generate
completions. There's now a `Context` for "how do we figure out what kind
of completions to offer" and also a `CollectionContext` for "how do we
figure out which completions are appropriate or not." We double down on
`Completions` as a collector and a single point of truth for this. It
now handles adding information to `Completion` (based on the context)
and also skipping completions that are inappropriate (instead of
filtering them after-the-fact).
We also bundle a bunch of state into a new `ContextCursor` type, and
then define a bunch of predicates/accessors on that type that were
previously free functions with loads of parameters.
Finally, we introduce more structure to ranking. Instead of an anonymous
tuple, we define an explicit type with some helper types to hopefully
make the influence on ranking from each constituent piece a bit clearer.
This does seem to fix one bug around detecting the target for non-import
completions, but otherwise should not have any changes in behavior.
This is meant to be a precursor to improving completion ranking.
## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Updates PT010(`pytest-raises-without-exception`) to recognize `match`
and `check` keyword arguments as valid alternatives to specifying an
exception class.
As of pytest 8.4.0, `pytest.raises()` can be called with only `match` or
`check` keyword arguments without an expected exception.
Fixes#18653
## Test Plan
<!-- How was it tested? -->
- Added test cases for `match`-only, `check`-only, and both arguments.
- `cargo test -p ruff_linter -- "pytestraiseswithoutexception"` passes
## Summary
I should have factored this better but this includes a drive-by move of
find_node to ruff_python_ast so ty_python_semantic can use it too.
* Fixes https://github.com/astral-sh/ty/issues/2017
## Test Plan
Snapshots galore
When inferring a specialization of a `Callable` type, we use the new
constraint set implementation. In the example in
https://github.com/astral-sh/ty/issues/1968, we end up with a constraint
set that includes all of the following clauses:
```
U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
M1 ≤ U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
M2 ≤ U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
M3 ≤ U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
M4 ≤ U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
M5 ≤ U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
M6 ≤ U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
M7 ≤ U_co ≤ M1 | M2 | M3 | M4 | M5 | M6 | M7
```
In general, we take the upper bounds of those constraints to get the
specialization. However, the upper bounds of those constraints are not
all guaranteed to be the same, and so first we need to intersect them
all together. In this case, the upper bounds are all identical, so their
intersection is trivial:
```
U_co = M1 | M2 | M3 | M4 | M5 | M6 | M7
```
But we were still doing the work of calculating that trivial
intersection 7 times. And each time we have to do 7^2 comparisons of the
`M*` classes, ending up with O(n^3) overall work.
This pattern is common enough that we can put in a quick heuristic to
prune identical copies of the same type before performing the
intersection.
Fixes https://github.com/astral-sh/ty/issues/1968
## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR implements a new semantic syntax error where annotated name
can't be global
example
```
x: int = 1
def f():
global x
x: str = "foo" # SyntaxError: annotated name 'x' can't be global
```
## Test Plan
<!-- How was it tested? -->
I have written tests as directed in #17412
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
Signed-off-by: 11happy <bhuminjaysoni@gmail.com>
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
## Summary
This contains two bug fixes:
- [Handle field specifier functions that accept
`**kwargs`](ad6918d505)
- [Recognize metaclass-based transformers as instances of
`DataclassInstance`](1a8e29b23c)
closes https://github.com/astral-sh/ty/issues/1987
## Test Plan
* New Markdown tests
* Made sure that the example in 1987 checks without errors
## Summary
Fixes https://github.com/astral-sh/ruff/issues/19771
Fixes incorrect parsing of Unicode named escape sequences like `Hey
\N{snowman}` in `FormatString`, which were being incorrectly split into
separate literal and field parts instead of being treated as a single
literal unit.
## Problem
The `FormatString` parser incorrectly handles Unicode named escape
sequences:
- **Current**: `Hey \N{snowman}` is parsed into 2 parts `Literal("Hey
\N")` & `Field("snowman")`
- **Expected**: `Hey \N{snowman}` should be parsed into 1 part
`Literal("Hey \N{snowman}")`
This affects f-string conversion rules when fixing `UP032` that rely on
proper format string parsing.
## Solution
I modified `parse_literal` to detect and handle Unicode named escape
sequences before parsing single characters:
- Introduced a flag to track when a backslash is "available" to escape
something.
- When the flag is `true`, and the text starts with `N{`, try to parse
the complete Unicode escape sequence as one unit, and set the flag to
`false` after parsing successfully.
- Set the flag to `false` when the backslash is already consumed.
## Manual Verification
`"\N{angle}AOB = {angle}°".format(angle=180)`
**Result**
```bash
def foo():
- "\N{angle}AOB = {angle}°".format(angle=180)
+ f"\N{angle}AOB = {180}°"
Would fix 1 error.
```
`"\N{snowman} {snowman}".format(snowman=1)`
**Result**
```bash
def foo():
- "\N{snowman} {snowman}".format(snowman=1)
+ f"\N{snowman} {1}"
Would fix 1 error.
```
`"\\N{snowman} {snowman}".format(snowman=1)`
**Result**
```bash
def foo():
- "\\N{snowman} {snowman}".format(snowman=1)
+ f"\\N{1} {1}"
Would fix 1 error.
```
## Test Plan
- Added test cases (happy case, invalid case, edge case) for
`FormatString` when parsing Unicode escape sequence.
- Updated snapshots.
## Summary
We're actually quite good at computing this but the main issue is just
that we compute it at the type-level and so wrap it in `Literal[...]`.
So just special-case the rendering of these to omit `Literal[...]` and
fallback to `...` in cases where the thing we'll show is probably
useless (i.e. `x: str = str`).
Fixes https://github.com/astral-sh/ty/issues/1882
This fixes a bug @zsol found running ty against pyx. His original repro
is:
```py
class Base:
def __init__(self) -> None: pass
class A(Base):
pass
def foo[T](callable: Callable[..., T]) -> T:
return callable()
a: A = foo(A)
```
The call at the bottom would fail, since we would infer `() -> Base` as
the callable type of `A`, when it should be `() -> A`.
The issue was how we add implicit annotations to `self` parameters.
Typically, we turn it into `self: Self`. But in cases where we don't
need to introduce a full typevar, we turn it into `self: [the class
itself]` — in this case, `self: Base`. Then, when turning the class
constructor into a callable, we would see this non-`Self` annotation and
think that it was important and load-bearing.
The fix is that we skip all implicit annotations when determining
whether the `self` annotation should take precedence in the callable's
return type.
This is a first stab at solving
https://github.com/astral-sh/ty/issues/500, at least in part, with the
old solver. We add a new `TypeRelation` that lets us opt into using
constraint sets to describe when a typevar is assignability to some
type, and then use that to calculate a constraint set that describes
when two callable types are assignable. If the callable types contain
typevars, that constraint set will describe their valid specializations.
We can then walk through all of the ways the constraint set can be
satisfied, and record a type mapping in the old solver for each one.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Co-authored-by: Alex Waygood <alex.waygood@gmail.com>
Fixes https://github.com/astral-sh/ty/issues/1787
## Summary
Allow method decorators returning Callables to presumptively propagate
"classmethod-ness" in the same way that they already presumptively
propagate "function-like-ness". We can't actually be sure that this is
the case, based on the decorator's annotations, but (along with other
type checkers) we heuristically assume it to be the case for decorators
applied via decorator syntax.
## Test Plan
Added mdtest.
Otherwise, given a case like this:
```
(lambda foo: (<CURSOR> + 1))(2)
```
we'll offer _argument_ completions for `foo` at the cursor position.
While we do actually want to offer completions for `foo` in this
context, it is currently difficult to do so. But we definitely don't
want to offer completions for `foo` as an argument to a function here.
Which is what we were doing.
We also add an end-to-end test here to verify that the actual label we
offer in completion suggestions includes the `=` suffix.
Closes https://github.com/astral-sh/ruff/pull/21970
Specifically, we make two changes:
1. We only show `import ...` when there is an actual import edit.
2. We now show the text we will insert. This means that when we
insert a qualified symbol, the qualification will show in the
completions suggested.
Ref https://github.com/astral-sh/ty/issues/1274#issuecomment-3352233790
It seems like this is perhaps a better default:
https://github.com/astral-sh/ty/issues/1274#issuecomment-3352233790
For me personally, I think I'd prefer the qualified
variant. But I can easily see this changing based on
the specific scenario. I think the thing that pushes
me toward prioritizing the unqualified variant is that
the user could have typed the qualified variant themselves,
but they didn't. So we should perhaps prioritize the
form they typed, which is unqualified.
Specifically, we want to test that something like `import typing`
should only be shown when we are actually going to insert an import.
*And* that when we insert a qualified name, then we should show it
as such in the completion suggestions.
Specifically, here, we'd probably like to add `TypedDict` to
the existing `from typing import ...` statement instead of
using the fully qualified `typing.TypedDict` form.
To test this, we add another snapshot mode for including imports
that a completion will insert when selected.
Ref https://github.com/astral-sh/ty/issues/1274#issuecomment-3352233790
## Summary
Infer `Literal[True]` for `isinstance(x, C)` calls when `x: T` and `T`
has a bound `B` that satisfies the `isinstance` check against `C`.
Similar for constrained typevars.
closes https://github.com/astral-sh/ty/issues/1895
## Test Plan
* New Markdown tests
* Verified the the example in the linked ticket checks without errors
In https://github.com/astral-sh/ruff/pull/21957, we tried to use
`union_or_intersection_elements_ordering` to provide a stable ordering
of the union and intersection elements that are created when determining
which type a typevar should specialize to. @AlexWaygood [pointed
out](https://github.com/astral-sh/ruff/pull/21551#discussion_r2616543762)
that this won't work, since that provides a consistent ordering within a
single process run, but does not provide a stable ordering across runs.
This is an attempt to produce a proper stable ordering for constraint
sets, so that we end up with consistent diagnostic and test output.
We do this by maintaining a new `source_order` field on each interior
BDD node, which records when that node's constraint was added to the
set. Several of the BDD operators (`and`, `or`, etc) now have
`_with_offset` variants, which update each `source_order` in the rhs to
be larger than any of the `source_order`s in the lhs. This is what
causes that field to be in line with (a) when you add each constraint to
the set, and (b) the order of the parameters you provide to `and`, `or`,
etc. Then we sort by that new field before constructing the
union/intersection types when creating a specialization.
In `for x in <CURSOR>` statements it's only valid to provide expressions
that eventually evaluate to an iterable. While it's extremely difficult
to know if something can evaulate to an iterable in a general case,
there are some suggestions we know can never lead to an iterable. Most
keywords are such and hence we remove them here.
## Summary
This suppresses statement-keywords from auto-complete suggestions in
`for x in <CURSOR>` statements where we know they can never be valid, as
whatever is typed has to (at some point) evaluate to an iterable.
It handles the core issue from
https://github.com/astral-sh/ty/issues/1774 but there's a lot of related
cases that probably has to be handled piece-wise.
## Test Plan
New tests and verifying in the playground.
This PR implements a modification (in preview) to fluent formatting for
method chains: We break _at_ the first call instead of _after_.
For example, we have the following diff between `main` and this PR (with
`line-length=8` so I don't have to stretch out the text):
```diff
x = (
- df.merge()
+ df
+ .merge()
.groupby()
.agg()
.filter()
)
```
## Explanation of current implementation
Recall that we traverse the AST to apply formatting. A method chain,
while read left-to-right, is stored in the AST "in reverse". So if we
start with something like
```python
a.b.c.d().e.f()
```
then the first syntax node we meet is essentially `.f()`. So we have to
peek ahead. And we actually _already_ do this in our current fluent
formatting logic: we peek ahead to count how many calls we have in the
chain to see whether we should be using fluent formatting or now.
In this implementation, we actually _record_ this number inside the enum
for `CallChainLayout`. That is, we make the variant `Fluent` hold an
`AttributeState`. This state can either be:
- The number of call-like attributes preceding the current attribute
- The state `FirstCallOrSubscript` which means we are at the first
call-like attribute in the chain (reading from left to right)
- The state `BeforeFirstCallOrSubscript` which means we are in the
"first group" of attributes, preceding that first call.
In our example, here's what it looks like at each attribute:
```
a.b.c.d().e.f @ Fluent(CallsOrSubscriptsPreceding(1))
a.b.c.d().e @ Fluent(CallsOrSubscriptsPreceding(1))
a.b.c.d @ Fluent(FirstCallOrSubscript)
a.b.c @ Fluent(BeforeFirstCallOrSubscript)
a.b @ Fluent(BeforeFirstCallOrSubscript)
```
Now, as we descend down from the parent expression, we pass along this
little piece of state and modify it as we go to track where we are. This
state doesn't do anything except when we are in `FirstCallOrSubscript`,
in which case we add a soft line break.
Closes#8598
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
When we calculate which typevars are inferable in a generic context, the
result might include more than the typevars bound by the generic
context. The canonical example is a generic method of a generic class:
```py
class C[A]:
def method[T](self, t: T): ...
```
Here, the inferable typevar set of `method` contains `Self` and `T`, as
you'd expect. (Those are the typevars bound by the method.) But it also
contains `A@C`, since the implicit `Self` typevar is defined as `Self:
C[A]`. That means when we call `method`, we need to mark `A@C` as
inferable, so that we can determine the correct mapping for `A@C` at the
call site.
Fixes https://github.com/astral-sh/ty/issues/1874
## Summary
If `import warnings` exists in the file, we will suggest an edit of
`deprecated -> warnings.deprecated` as "qualify warnings.deprecated"
## Test Plan
Should test more cases...
## Summary
- Treat `if TYPE_CHECKING` blocks the same as stub files (the feature
requested in https://github.com/astral-sh/ty/issues/1216)
- We currently only allow `@abstractmethod`-decorated methods to omit
the implementation if they're methods in classes that have _exactly_
`ABCMeta` as their metaclass. That seems wrong -- `@abstractmethod` has
the same semantics if a class has a subclass of `ABCMeta` as its
metaclass. This PR fixes that too. (I'm actually not _totally_ sure we
should care what the class's metaclass is at all -- see discussion in
https://github.com/astral-sh/ty/issues/1877#issue-3725937441... but the
change this PR is making seems less wrong than what we have currently,
anyway.)
Fixes https://github.com/astral-sh/ty/issues/1216
## Test Plan
Mdtests and snapshots
## Summary
I assume that the class has been renamed or split since this assertion
was created.
## Test Plan
Compiled locally, nothing more. Relying on CI given the triviality of
this change.
We now allow the lower and upper bounds of a constraint to be gradual.
Before, we would take the top/bottom materializations of the bounds.
This required us to pass in whether the constraint was intended for a
subtyping check or an assignability check, since that would control
whether we took the "restrictive" or "permissive" materializations,
respectively.
Unfortunately, doing so means that we lost information about whether the
original query involves a non-fully-static type. This would cause us to
create specializations like `T = object` for the constraint `T ≤ Any`,
when it would be nicer to carry through the gradual type and produce `T
= Any`.
We're not currently using constraint sets for subtyping checks, nor are
we going to in the very near future. So for now, we're going to assume
that constraint sets are always used for assignability checks, and allow
the lower/upper bounds to not be fully static. Once we get to the point
where we need to use constraint sets for subtyping checks, we will
consider how best to record this information in constraints.
## Summary
This PR makes explicit specialization of a type variable itself an
error, and the result of the specialization is `Unknown`.
The change also fixes https://github.com/astral-sh/ty/issues/1794.
## Test Plan
mdtests updated
new corpus test
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
This PR takes the improvements we made to unsupported-comparison
diagnostics in https://github.com/astral-sh/ruff/pull/21737, and extends
them to other `unsupported-operator` diagnostics.
## Test Plan
Mdtests and snapshots
## Summary
Working on py-fuzzer recently (AKA, a Python project!) reminded me how
cool our "inlay hint goto-definition feature" is. So this PR adds a
bunch more of that!
I also made a couple of other minor changes to type display. For
example, in the playground, this snippet:
```py
def f(): ...
reveal_type(f.__get__)
```
currently leads to this diagnostic:
```
Revealed type: `<method-wrapper `__get__` of `f`>` (revealed-type) [Ln 2, Col 13]
```
But the fact that we have backticks both around the type display and
inside the type display isn't _great_ there. This PR changes it to
```
Revealed type: `<method-wrapper '__get__' of function 'f'>` (revealed-type) [Ln 2, Col 13]
```
which avoids the nested-backticks issue in diagnostics, and is more
similar to our display for various other `Type` variants such as
class-literal types (`<class 'Foo'>`, etc., not ``<class `Foo`>``).
## Test Plan
inlay snapshots added; mdtests updated
Summary
--
Following #8179, we now format long lambda expressions a bit more like
Black, preferring to keep long parameter lists on a single line, but we
go one step further to break the body itself across multiple lines and
parenthesize it if it's still too long. This PR documents both the
stable deviation that breaks parameters across multiple lines, and the
new preview deviation that breaks the body instead.
I also fixed a couple of typos in the section immediately above my
addition.
Test Plan
--
I tested all of the snippets here against `main` for the preview
behavior, our playground for the stable behavior, and Black's playground
for their behavior
## Summary
This PR makes two changes to our formatting of `lambda` expressions:
1. We now parenthesize the body expression if it expands
2. We now try to keep the parameters on a single line
The latter of these fixes#8179:
Black formatting and this PR's formatting:
```py
def a():
return b(
c,
d,
e,
f=lambda self, *args, **kwargs: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
*args, **kwargs
),
)
```
Stable Ruff formatting
```py
def a():
return b(
c,
d,
e,
f=lambda self,
*args,
**kwargs: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(*args, **kwargs),
)
```
We don't parenthesize the body expression here because the call to
`aaaa...` has its own parentheses, but adding a binary operator shows
the new parenthesization:
```diff
@@ -3,7 +3,7 @@
c,
d,
e,
- f=lambda self, *args, **kwargs: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
- *args, **kwargs
- ) + 1,
+ f=lambda self, *args, **kwargs: (
+ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(*args, **kwargs) + 1
+ ),
)
```
This is actually a new divergence from Black, which formats this input
like this:
```py
def a():
return b(
c,
d,
e,
f=lambda self, *args, **kwargs: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa(
*args, **kwargs
)
+ 1,
)
```
But I think this is an improvement, unlike the case from #8179.
One other, smaller benefit is that because we now add parentheses to
lambda bodies, we also remove redundant parentheses:
```diff
@pytest.mark.parametrize(
"f",
[
- lambda x: (x.expanding(min_periods=5).cov(x, pairwise=True)),
- lambda x: (x.expanding(min_periods=5).corr(x, pairwise=True)),
+ lambda x: x.expanding(min_periods=5).cov(x, pairwise=True),
+ lambda x: x.expanding(min_periods=5).corr(x, pairwise=True),
],
)
def test_moment_functions_zero_length_pairwise(f):
```
## Test Plan
New tests taken from #8465 and probably a few more I should grab from
the ecosystem results.
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
By teaching desperate resolution to try every possible ancestor that
doesn't have an `__init__.py(i)` when resolving absolute imports.
* Fixes https://github.com/astral-sh/ty/issues/1782
... and also `__all__.extend(submodule.__all__)`.
I originally left out support for this since I was unclear on whether
we'd really need it. But it turns out this is used somewhat frequently.
For example, in `numpy`.
See the comments on the new `Imports` type for how we approach this.
Partially addresses https://github.com/astral-sh/ty/issues/1732
## Summary
Don't union the previous type in fixpoint iteration if the previous type
contains a `Divergent` from the current cycle and the latest type does
not. The theory here, as outlined by @mtshiba at
https://github.com/astral-sh/ty/issues/1732#issuecomment-3609937420, is
that oscillation can't occur by removing and then reintroducing a
`Divergent` type repeatedly, since `Divergent` types are only introduced
at the start of fixpoint iteration.
## Test Plan
Removes a `Divergent` type from the added mdtest, doesn't otherwise
regress any tests.
## Summary
This PR includes the following changes:
* When attempting to specialize a non-generic type (or a type that is
already specialized), the result is `Unknown`. Also, the error message
is improved.
* When an implicit type alias is incorrectly specialized, the result is
`Unknown`. Also, the error message is improved.
* When only some of the type alias bounds and constraints are not
satisfied, not all substitutions are `Unknown`.
* Double specialization is prohibited. e.g. `G[int][int]`
Furthermore, after applying this PR, the fuzzing tests for seeds 1052
and 4419, which panic in main, now pass.
This is because the false recursions on type variables have been
removed.
```python
# name_2[0] => Unknown
class name_1[name_2: name_2[0]]:
def name_4(name_3: name_2, /):
if name_3:
pass
# (name_5 if unique_name_0 else name_1)[0] => Unknown
def name_4[name_5: (name_5 if unique_name_0 else name_1)[0], **name_1](): ...
```
## Test Plan
New corpus test
mdtest files updated
As described in astral-sh/ty#1729, we previously had a salsa cycle when
inferring the signature of many function definitions.
The most obvious case happened when (a) the function was decorated, (b)
it had no PEP-695 type params, and (c) annotations were not always
deferred (e.g. in a stub file). We currently evaluate and apply function
decorators eagerly, as part of `infer_function_definition`. Applying a
decorator requires knowing the signature of the function being
decorated. There were two places where signature construction called
`infer_definition_types` cyclically.
The simpler case was that we were looking up the generic context and
decorator list of the function to determine whether it has an implicit
`self` parameter. Before, we used `infer_definition_types` to determine
that information. But since we're in the middle of signature
construction for the function, we can just thread the information
through directly.
The harder case is that signature construction requires knowing the
inferred parameter and return type annotations. When (b) and (c) hold,
those type annotations are inferred in `infer_function_definition`! (In
theory, we've already finished that by the time we start applying
decorators, but signature construction doesn't know that.)
If annotations are deferred, the params/return annotations are inferred
in `infer_deferred_types`; if there are PEP-695 type params, they're
inferred in `infer_function_type_params`. Both of those are different
salsa queries, and don't induce this cycle.
So the quick fix here is to always defer inference of the function
params/return, so that they are always inferred under a different salsa
query.
A more principled fix would be to apply decorators lazily, just like we
construct signatures lazily. But that is a more invasive fix.
Fixesastral-sh/ty#1729
---------
Co-authored-by: Alex Waygood <alex.waygood@gmail.com>
## Summary
Ignores `#ruff:isort` when parsing suppressions similar to `#ruff:noqa`.
Should clear up ecosystem issues in #21908
## Test Plan
cargo tests
Partially addresses https://github.com/astral-sh/ty/issues/1732
Fixes https://github.com/astral-sh/ty/issues/1800
## Summary
At each fixpoint iteration, we union the "previous" and "current"
iteration types, to ensure that the type can only widen at each
iteration. This prevents oscillation and ensures convergence.
But some unions triggered by this behavior (in particular, unions of
differently-specialized generic-aliases of the same class) never
simplify, and cause spurious errors. Since we haven't seen examples of
oscillating types involving class-literal or generic-alias types, just
don't union those.
There may be more thorough/principled ways to avoid undesirable unions
in fixpoint iteration, but this narrow change seems like it results in
strict improvement.
## Test Plan
Removes two false positive `unsupported-class-base` in mdtests, and
several in the ecosystem, without causing other regression.
I recently started noticing this showing up in the logs for every scope
based completion request:
```
2025-12-11 11:25:35.704329935 DEBUG request{id=29 method="textDocument/completion"}:map_stub_definition: Module `builtins` not found while looking in parent dirs
```
And in particular, it was repeated several times. This was confusing to
me because, well, of course `builtins` should resolve.
This particular code path comes from looking for the docstrings
of completion items. This involves a spelunking that ultimately
tries to resolve a "real" module if the stub doesn't have available
docstrings. But I guess there is no "real" `builtins` module, so
`resolve_real_module` fails. Which is fine, but the noisy logs were
annoying since this is an expected case.
So here, we carve out a short circuit for `builtins` and also improve
the log message.
These routines don't return *all* symbols/members, but rather,
only *for* a particular scope. We do specifically want to add
some routines that return *all* symbols/members, and this naming
scheme made that confusing. It was also inconsistent with other
routines like `all_end_of_scope_symbol_declarations` which *do*
return *all* symbols.
This PR improves the overload call resolution tracing messages as:
- Use `trace` level instead of `debug` level
- Add a `trace_span` which contains the call arguments and signature
- Remove the signature from individual tracing messages
## Summary
We currently perform a subtyping check, similar to what we were doing
for `@final` instances before
https://github.com/astral-sh/ruff/pull/21167, which is incorrect, e.g.
we currently consider `type[X[Any]]` and `type[X[T]]]` disjoint (where
`X` is `@final`).
This fixes the logic error that @sharkdp
[found](https://github.com/astral-sh/ruff/pull/21871#discussion_r2605755588)
in the constraint set upper bound normalization logic I introduced in
#21871.
I had originally claimed that `(T ≤ α & ~β)` should simplify into `(T ≤
α) ∧ ¬(T ≤ β)`. But that also suggests that `T ≤ ~β` should simplify to
`¬(T ≤ β)` on its own, and that's not correct.
The correct simplification is that `~α` is an "atomic" type, not an
"intersection" for the purposes of our upper bound simplifcation. So `(T
≤ α & ~β)` should simplify to `(T ≤ α) ∧ (T ≤ ~β)`. That is, break apart
the elements of a (proper) intersection, regardless of whether each
element is negated or not.
This PR fixes the logic, adds a test case, and updates the comments to
be hopefully more clear and accurate.
Fixes https://github.com/astral-sh/ty/issues/1832, fixes
https://github.com/astral-sh/ty/issues/1513
## Summary
A class object `C` (for which we infer an unspecialized `ClassLiteral`
type) should always be assignable to the type `type[C]` (which is
default-specialized, if `C` is generic). We already implemented this for
most cases, but we missed the case of a generic final type, where we
simplify `type[C]` to the `GenericAlias` type for the default
specialization of `C`. So we also need to implement this assignability
of generic `ClassLiteral` types as-if default-specialized.
## Test Plan
Added mdtests that failed before this PR.
---------
Co-authored-by: David Peter <mail@david-peter.de>
## Summary
Respect typevar bounds and constraints when matching against a union.
For example:
```py
def accepts_t_or_int[T_str: str](x: T_str | int) -> T_str:
raise NotImplementedError
reveal_type(accepts_t_or_int("a")) # ok, reveals `Literal["a"]`
reveal_type(accepts_t_or_int(1)) # ok, reveals `Unknown`
class Unrelated: ...
# error: [invalid-argument-type] "Argument type `Unrelated` does not
# satisfy upper bound `str` of type variable `T_str`"
accepts_t_or_int(Unrelated())
```
Previously, the last call succeed without any errors. Worse than that,
we also incorrectly solved `T_str = Unrelated`, which often lead to
downstream errors.
closes https://github.com/astral-sh/ty/issues/1837
## Ecosystem impact
Looks good!
* Lots of removed false positives, often because we previously selected
a wrong overload for a generic function (because we didn't respect the
typevar bound in an earlier overload).
* We now understand calls to functions accepting an argument of type
`GenericPath: TypeAlias = AnyStr | PathLike[AnyStr]`. Previously, we
would incorrectly match a `Path` argument against the `AnyStr` typevar
(violating its constraints), but now we match against `PathLike`.
## Performance
Another regression on `colour`. This package uses `numpy` heavily. And
`numpy` is the codebase that originally lead me to this bug. The fix
here allows us to infer more precise `np.array` types in some cases, so
it's reasonable that we just need to perform more work.
The fix here also requires us to look at more union elements when we
would previously short-circuit incorrectly, so some more work needs to
be done in the solver.
## Test Plan
New Markdown tests
This hack was introduced to reduce the amount of warnings that users
would get while transitioning to the new settings format
(https://github.com/astral-sh/ruff/pull/19787) but now that we're near
the beta release, it would be good to remove this.
In a constraint set, it's not useful for an upper bound to be an
intersection type, or for a lower bound to be a union type. Both of
those can be rewritten as simpler BDDs:
```
T ≤ α & β ⇒ (T ≤ α) ∧ (T ≤ β)
T ≤ α & ¬β ⇒ (T ≤ α) ∧ ¬(T ≤ β)
α | β ≤ T ⇒ (α ≤ T) ∧ (β ≤ T)
```
We were seeing performance issues on #21551 when _not_ performing this
simplification. For instance, `pandas` was producing some constraint
sets involving intersections of 8-9 different types. Our sequent map
calculation was timing out calculating all of the different permutations
of those types:
```
t1 & t2 & t3 → t1
t1 & t2 & t3 → t2
t1 & t2 & t3 → t3
t1 & t2 & t3 → t1 & t2
t1 & t2 & t3 → t1 & t3
t1 & t2 & t3 → t2 & t3
```
(and then imagine what that looks like for 9 types instead of 3...)
With this change, all of those permutations are now encoded in the BDD
structure itself, which is very good at simplifying that kind of thing.
Pulling this out of #21551 for separate review.
#21744 fixed some non-determinism in our constraint set implementation
by switching our BDD representation from being "fully reduced" to being
"quasi-reduced". We still deduplicate identical nodes (via salsa
interning), but we removed the logic to prune redundant nodes (one with
identical outgoing true and false edges). This ensures that the BDD
"remembers" all of the individual constraints that it was created with.
However, that comes at the cost of creating larger BDDs, and on #21551
that was causing performance issues. `scikit-learn` was producing a
function signature with dozens of overloads, and we were trying to
create a constraint set that would map a return type typevar to any of
those overload's return types. This created a combinatorial explosion in
the BDD, with by far most of the BDD paths leading to the `never`
terminal.
This change updates the quasi-reduction logic to prune nodes that are
redundant _because both edges lead to the `never` terminal_. In this
case, we don't need to "remember" that constraint, since no assignment
to it can lead to a valid specialization. So we keep the "memory" of our
quasi-reduced structure, while still pruning large unneeded portions of
the BDD structure.
Pulling this out of https://github.com/astral-sh/ruff/pull/21551 for
separate review.
## Summary
This is a follow-up to #21868. As soon as I started merging #21868 into
#21385, I realized that I had missed a test case with `**kwargs` after
the `*args` parameter. Such a case is supposed to be formatted on one
line like:
```py
# input
(
lambda
# comment
*x,
**y: x
)
# output
(
lambda
# comment
*x, **y: x
)
```
which you can still see on the
[playground](https://play.ruff.rs/bd88d339-1358-40d2-819f-865bfcb23aef?secondary=Format),
but on `main` after #21868, this was formatted as:
```py
(
lambda
# comment
*x,
**y: x
)
```
because the leading comment on the first parameter caused the whole
group around the parameters to break.
Instead of making these comments leading comments on the first
parameter, this PR makes them leading comments on the parameters list as
a whole.
## Test Plan
New tests, and I will also try merging this into #21385 _before_ opening
it for review this time.
<hr>
(labeling `internal` since #21868 should not be released before some
kind of fix)
## Summary
This PR adds special handling for `asynccontextmanager` calls as a
temporary solution for https://github.com/astral-sh/ty/issues/1804. We
will be able to remove this soon once we have support for generic
protocols in the solver.
closes https://github.com/astral-sh/ty/issues/1804
## Ecosystem
```diff
+ tests/test_downloadermiddleware.py:305:56: error[invalid-argument-type] Argument to bound method `download` is incorrect: Expected `Spider`, found `Unknown | Spider | None`
+ tests/test_downloadermiddleware.py:305:56: warning[possibly-missing-attribute] Attribute `spider` may be missing on object of type `Crawler | None`
```
These look like true positives
```diff
+ pymongo/asynchronous/database.py:1021:35: error[invalid-assignment] Object of type `(AsyncClientSession & ~AlwaysTruthy & ~AlwaysFalsy) | (_ServerMode & ~AlwaysFalsy) | Unknown | Primary` is not assignable to `_ServerMode | None`
+ pymongo/asynchronous/database.py:1025:17: error[invalid-argument-type] Argument to bound method `_conn_for_reads` is incorrect: Expected `_ServerMode`, found `_ServerMode | None`
```
Known problems or true positives, just caused by the new type for
`session`
```diff
- src/integrations/prefect-sqlalchemy/prefect_sqlalchemy/database.py:269:16: error[invalid-return-type] Return type does not match returned value: expected `Connection | AsyncConnection`, found `_GeneratorContextManager[Unknown, None, None] | _AsyncGeneratorContextManager[Unknown, None] | Connection | AsyncConnection`
+ src/integrations/prefect-sqlalchemy/prefect_sqlalchemy/database.py:269:16: error[invalid-return-type] Return type does not match returned value: expected `Connection | AsyncConnection`, found `_GeneratorContextManager[Unknown, None, None] | _AsyncGeneratorContextManager[AsyncConnection, None] | Connection | AsyncConnection`
```
Just a more concrete type
```diff
- src/prefect/flow_engine.py:1277:24: error[missing-argument] No argument provided for required parameter `cls`
- src/prefect/server/api/server.py:696:49: error[missing-argument] No argument provided for required parameter `cls`
- src/prefect/task_engine.py:1426:24: error[missing-argument] No argument provided for required parameter `cls`
```
Good
## Test Plan
* Adapted and newly added Markdown tests
* Tested on internal codebase
Summary
--
This PR makes two changes to comment placement in lambda parameters.
First, we
now insert a line break if the first parameter has a leading comment:
```py
# input
(
lambda
* # comment 2
x:
x
)
# main
(
lambda # comment 2
*x: x
)
# this PR
(
lambda
# comment 2
*x: x
)
```
Note the missing space in the output from main. This case is currently
unstable
on main. Also note that the new formatting is more consistent with our
stable
formatting in cases where the lambda has its own dangling comment:
```py
# input
(
lambda # comment 1
* # comment 2
x:
x
)
# output
(
lambda # comment 1
# comment 2
*x: x
)
```
and when a parameter without a comment precedes the split `*x`:
```py
# input
(
lambda y,
* # comment 2
x:
x
)
# output
(
lambda y,
# comment 2
*x: x
)
```
This does change the stable formatting, but I think such cases are rare
(expecting zero hits in the ecosystem report), this fixes an existing
instability, and it should not change any code we've previously
formatted.
Second, this PR modifies the comment placement such that `# comment 2`
in these
outputs is still a leading comment on the parameter. This is also not
the case
on main, where it becomes a [dangling lambda
comment](https://play.ruff.rs/3b29bb7e-70e4-4365-88e0-e60fe1857a35?secondary=Comments).
This doesn't cause any
instability that I'm aware of on main, but it does cause problems when
trying to
adjust the placement of dangling lambda comments in #21385. Changing the
placement in this way should not affect any formatting here.
Test Plan
--
New lambda tests, plus existing tests covering the cases above with
multiple
comments around the parameters (see lambda.py 122-143, and 122-205 or so
more
broadly)
I also checked manually that the comments are now leading on the
parameter:
```shell
❯ cargo run --bin ruff_python_formatter -- --emit stdout --target-version 3.10 --print-comments <<EOF
(
lambda
# comment 2
*x: x
)
EOF
Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.15s
Running `target/debug/ruff_python_formatter --emit stdout --target-version 3.10 --print-comments`
# Comment decoration: Range, Preceding, Following, Enclosing, Comment
21..32, None, Some((Parameters, 37..39)), (ExprLambda, 6..42), "# comment 2"
{
Node {
kind: Parameter,
range: 37..39,
source: `*x`,
}: {
"leading": [
SourceComment {
text: "# comment 2",
position: OwnLine,
formatted: true,
},
],
"dangling": [],
"trailing": [],
},
}
(
lambda
# comment 2
*x: x
)
```
But I didn't see a great place to put a test like this. Is there
somewhere I can assert this comment placement since it doesn't affect
any formatting yet? Or is it okay to wait until we use this in #21385?
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Closes#17347
Goal is to detect the useless exception statement not just for builtin
exceptions but also custom (user defined) ones.
## Test Plan
<!-- How was it tested? -->
I added test cases in the rule fixture and updated the insta snapshot.
Note that I first moved up a test case case which was at the bottom to
the correct "violation category".
I wasn't sure if I should create new test cases or just insert inside
those tests. I know that ideally each test case should test only one
thing, but here, duplicating twice 12 test cases seemed very verbose,
and actually less maintainable in the future. The drawback is that the
diff in the snapshot is hard to review, sorry. But you can see that the
snapshot gives 38 diagnostics, which is what we expect.
Alternatively, I also created this file for manual testing.
```py
# tmp/test_error.py
class MyException(Exception):
...
class MyBaseException(BaseException):
...
class MyValueError(ValueError):
...
class MyExceptionCustom(Exception):
...
class MyBaseExceptionCustom(BaseException):
...
class MyValueErrorCustom(ValueError):
...
class MyDeprecationWarning(DeprecationWarning):
...
class MyDeprecationWarningCustom(MyDeprecationWarning):
...
class MyExceptionGroup(ExceptionGroup):
...
class MyExceptionGroupCustom(MyExceptionGroup):
...
class MyBaseExceptionGroup(ExceptionGroup):
...
class MyBaseExceptionGroupCustom(MyBaseExceptionGroup):
...
def foo():
Exception("...")
BaseException("...")
ValueError("...")
RuntimeError("...")
DeprecationWarning("...")
GeneratorExit("...")
SystemExit("...")
ExceptionGroup("eg", [ValueError(1), TypeError(2), OSError(3), OSError(4)])
BaseExceptionGroup("eg", [ValueError(1), TypeError(2), OSError(3), OSError(4)])
MyException("...")
MyBaseException("...")
MyValueError("...")
MyExceptionCustom("...")
MyBaseExceptionCustom("...")
MyValueErrorCustom("...")
MyDeprecationWarning("...")
MyDeprecationWarningCustom("...")
MyExceptionGroup("...")
MyExceptionGroupCustom("...")
MyBaseExceptionGroup("...")
MyBaseExceptionGroupCustom("...")
```
and you can run this to check the PR:
```sh
target/debug/ruff check tmp/test_error.py --select PLW0133 --unsafe-fixes --diff --no-cache --isolated --target-version py310
target/debug/ruff check tmp/test_error.py --select PLW0133 --unsafe-fixes --diff --no-cache --isolated --target-version py314
```
## Summary
This fixes https://github.com/astral-sh/ty/issues/1736 where recursive
generic protocols with growing specializations caused a stack overflow.
The issue occurred with protocols like:
```python
class C[T](Protocol):
a: 'C[set[T]]'
```
When checking `C[set[int]]` against e.g. `C[Unknown]`, member `a`
requires checking `C[set[set[int]]]`, which requires
`C[set[set[set[int]]]]`, etc. Each level has different type
specializations, so the existing cycle detection (using full types as
cache keys) didn't catch the infinite recursion.
This fix adds a simple recursion depth limit (64) to the CycleDetector.
When the depth exceeds the limit, we return the fallback value (assume
compatible) to safely terminate the recursion.
This is a bit of a blunt hammer, but it should be broadly effective to
prevent stack overflow in any nested-relation case, and it's hard to
imagine that non-recursive nested relation comparisons of depth > 64
exist much in the wild.
## Test Plan
Added mdtest.
## Summary
This PR allows our generics solver to find a solution for `T` in cases
like the following:
```py
def extract_t[T](x: P[T] | Q[T]) -> T:
raise NotImplementedError
reveal_type(extract_t(P[int]())) # revealed: int
reveal_type(extract_t(Q[str]())) # revealed: str
```
closes https://github.com/astral-sh/ty/issues/1772
closes https://github.com/astral-sh/ty/issues/1314
## Ecosystem
The impact here looks very good!
It took me a long time to figure this out, but the new diagnostics on
bokeh are actually true positives. I should have tested with another
type-checker immediately, I guess. All other type checkers also emit
errors on these `__init__` calls. MRE
[here](https://play.ty.dev/5c19d260-65e2-4f70-a75e-1a25780843a2) (no
error on main, diagnostic on this branch)
A lot of false positives on home-assistant go away for calls to
functions like
[`async_listen`](180053fe98/homeassistant/core.py (L1581-L1587))
which take a `event_type: EventType[_DataT] | str` parameter. We can now
solve for `_DataT` here, which was previously falling back to its
default value, and then caused problems because it was used as an
argument to an invariant generic class.
## Test Plan
New Markdown tests
## Summary
fixes: https://github.com/astral-sh/ty/issues/1809
I took this chance to add some debug level tracing logs for overload
call evaluation similar to Doug's implementation in `constraints.rs`.
## Test Plan
- Add new mdtests
- Tested it against `sqlalchemy.select` in pyx which results in the
correct overload being matched
While still under development, it's far enough along now that we think
it's worth enabling it by default. This should also help give us
feedback for how it behaves.
This PR adds a "completion settings" grouping similar to inlay hints. We
only have an auto-import setting there now, but I expect we'll add more
options to configure completion behavior in the future.
Closesastral-sh/ty#1765
This adds autocomplete suggestions for function arguments. For example,
`okay` in:
```python
def foo(okay=None):
foo(o<CURSOR>
```
This also ensures that we don't suggest a keyword argument if it has
already been used.
Closesastral-sh/issues#1550
Closes issue #21565
## Summary
As pointed out in the issue, slices are currently flagged by B008 but
this behavior is incorrect because slices are immutable.
## Test Plan
Added a test case in the "B006_B008.py" fixture. Sorry for the diff in
the snapshots, the only thing that changes in those flies is the line
numbers, though.
You can also test this manually with this file:
```py
# test_slice.py
def c(d=slice(0, 3)): ...
```
```sh
> target/debug/ruff check tmp/test_slice.py --no-cache --select B008
All checks passed!
```
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## Summary
Fixes https://github.com/astral-sh/ruff/issues/8774
This PR fixes `pydocstyle` incorrectly flagging missing argument for
arguments with `Unpack` type annotation by extracting the `kwarg` `D417`
suppression logic into a helper function for future rules as needed.
## Problem Statement
The below example was incorrectly triggering `D417` error for missing
`**kwargs` doc.
```python
class User(TypedDict):
id: int
name: str
def do_something(some_arg: str, **kwargs: Unpack[User]):
"""Some doc
Args:
some_arg: Some argument
"""
```
<img width="1135" height="276" alt="image"
src="https://github.com/user-attachments/assets/42fa4bb9-61a5-4a70-a79c-0c8922a3ee66"
/>
`**kwargs: Unpack[User]` indicates the function expects keyword
arguments that will be unpacked. Ideally, the individual fields of the
User `TypedDict` should be documented, not in the `**kwargs` itself. The
`**kwargs` parameter acts as a semantic grouping rather than a parameter
requiring documentation.
## Solution
As discussed in the linked issue, it makes sense to suppress the `D417`
for parameters with `Unpack` annotation. I extract a helper function to
solely check `D417` should be suppressed with `**kwarg: Unpack[T]`
parameter, this function can also be unit tested independently and
reduce complexity of current `missing_args` check function. This also
makes it easier to add additional rules in the future.
_✏️ Note:_ This is my first PR in this repo, as I've learned a ton from
it, please call out anything that could be improved. Thanks for making
this excellent tool 👏
## Test Plan
Add 2 test cases in `D417.py` and update snapshots.
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
## Summary
By taking a purely syntactic approach to the problem of trivial
initializer calls we can supress `x: T = T()`, `x: T = x.y.T()` and `x:
MyNewType = MyNewType(0)` but still display `x: T[U] = T()`.
The place where we drop a ball is this does not compose with our
analysis for supressing `x = (0, "hello")` as `x = (0, T())` and `x =
(T(), T())` will still get inlay hints (I don't think this is a huge
deal).
* fixes https://github.com/astral-sh/ty/issues/1516
## Test Plan
Existing snapshots cover this well.
## Summary
If you pass a non-tuple to `Annotated`, we end up running inference on
it twice. I _think_ the only case here is `Annotated[]`, where we insert
a (fake) empty `Name` node in the slice.
Closes https://github.com/astral-sh/ty/issues/1801.
## Summary
Increase our SQLAlchemy test coverage to make sure we understand
`Session.scalar`, `Session.scalars`, `Session.execute` (and their async
equivalents), as well as `Result.tuples`, `Result.one_or_none`,
`Row._tuple`.
## Summary
This PR adds the possibility to write mdtests that specify external
dependencies in a `project` section of TOML blocks. For example, here is
a test that makes sure that we understand Pydantic's dataclass-transform
setup:
````markdown
```toml
[environment]
python-version = "3.12"
python-platform = "linux"
[project]
dependencies = ["pydantic==2.12.2"]
```
```py
from pydantic import BaseModel
class User(BaseModel):
id: int
name: str
user = User(id=1, name="Alice")
reveal_type(user.id) # revealed: int
reveal_type(user.name) # revealed: str
# error: [missing-argument] "No argument provided for required parameter
`name`"
invalid_user = User(id=2)
```
````
## How?
Using the `python-version` and the `dependencies` fields from the
Markdown section, we generate a `pyproject.toml` file, write it to a
temporary directory, and use `uv sync` to install the dependencies into
a virtual environment. We then copy the Python source files from that
venv's `site-packages` folder to a corresponding directory structure in
the in-memory filesystem. Finally, we configure the search paths
accordingly, and run the mdtest as usual.
I fully understand that there are valid concerns here:
* Doesn't this require network access? (yes, it does)
* Is this fast enough? (`uv` caching makes this almost unnoticeable,
actually)
* Is this deterministic? ~~(probably not, package resolution can depend
on the platform you're on)~~ (yes, hopefully)
For this reason, this first version is opt-in, locally. ~~We don't even
run these tests in CI (even though they worked fine in a previous
iteration of this PR).~~ You need to set `MDTEST_EXTERNAL=1`, or use the
new `-e/--enable-external` command line option of the `mdtest.py`
runner. For example:
```bash
# Skip mdtests with external dependencies (default):
uv run crates/ty_python_semantic/mdtest.py
# Run all mdtests, including those with external dependencies:
uv run crates/ty_python_semantic/mdtest.py -e
# Only run the `pydantic` tests. Use `-e` to make sure it is not skipped:
uv run crates/ty_python_semantic/mdtest.py -e pydantic
```
## Why?
I believe that this can be a useful addition to our testing strategy,
which lies somewhere between ecosystem tests and normal mdtests.
Ecosystem tests cover much more code, but they have the disadvantage
that we only see second- or third-order effects via diagnostic diffs. If
we unexpectedly gain or lose type coverage somewhere, we might not even
notice (assuming the gradual guarantee holds, and ecosystem code is
mostly correct). Another disadvantage of ecosystem checks is that they
only test checked-in code that is usually correct. However, we also want
to test what happens on wrong code, like the code that is momentarily
written in an editor, before fixing it. On the other end of the spectrum
we have normal mdtests, which have the disadvantage that they do not
reflect the reality of complex real-world code. We experience this
whenever we're surprised by an ecosystem report on a PR.
That said, these tests should not be seen as a replacement for either of
these things. For example, we should still strive to write detailed
self-contained mdtests for user-reported issues. But we might use this
new layer for regression tests, or simply as a debugging tool. It can
also serve as a tool to document our support for popular third-party
libraries.
## Test Plan
* I've been locally using this for a couple of weeks now.
* `uv run crates/ty_python_semantic/mdtest.py -e`
## Summary
As-is, a single-element tuple gets destructured via:
```rust
let arguments = if let ast::Expr::Tuple(tuple) = slice {
&*tuple.elts
} else {
std::slice::from_ref(slice)
};
```
But then, because it's a single element, we call
`infer_annotation_expression_impl`, passing in the tuple, rather than
the first element.
Closes https://github.com/astral-sh/ty/issues/1793.
Closes https://github.com/astral-sh/ty/issues/1768.
---------
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This PR adds the same `minimal-size` profile as `uv` repo workspace has
```toml
# Profile to build a minimally sized binary for uv-build
[profile.minimal-size]
inherits = "release"
opt-level = "z"
# This will still show a panic message, we only skip the unwind
panic = "abort"
codegen-units = 1
```
but removes its `panic = "abort"` setting
- As discussed in #21825
Compared to the ones pre-built via `uv tool install`, this builds 35%
smaller ruff and 24% smaller ty binaries
(as measured
[here](https://github.com/lmmx/just-pre-commit/blob/master/refresh_binaries.sh))
## Summary
Closes: https://github.com/astral-sh/ty/issues/157
This PR adds support for the following capabilities involving a
`ParamSpec` type variable:
- Representing `P.args` and `P.kwargs` in the type system
- Matching against a callable containing `P` to create a type mapping
- Specializing `P` against the stored parameters
The value of a `ParamSpec` type variable is being represented using
`CallableType` with a `CallableTypeKind::ParamSpecValue` variant. This
`CallableTypeKind` is expanded from the existing `is_function_like`
boolean flag. An `enum` is used as these variants are mutually
exclusive.
For context, an initial iteration made an attempt to expand the
`Specialization` to use `TypeOrParameters` enum that represents that a
type variable can specialize into either a `Type` or `Parameters` but
that increased the complexity of the code as all downstream usages would
need to handle both the variants appropriately. Additionally, we'd have
also need to establish an invariant that a regular type variable always
maps to a `Type` while a paramspec type variable always maps to a
`Parameters`.
I've intentionally left out checking and raising diagnostics when the
`ParamSpec` type variable and it's components are not being used
correctly to avoid scope increase and it can easily be done as a
follow-up. This would also include the scoping rules which I don't think
a regular type variable implements either.
## Test Plan
Add new mdtest cases and update existing test cases.
Ran this branch on pyx, no new diagnostics.
### Ecosystem analysis
There's a case where in an annotated assignment like:
```py
type CustomType[P] = Callable[...]
def value[**P](...): ...
def another[**P](...):
target: CustomType[P] = value
```
The type of `value` is a callable and it has a paramspec that's bound to
`value`, `CustomType` is a type alias that's a callable and `P` that's
used in it's specialization is bound to `another`. Now, ty infers the
type of `target` same as `value` and does not use the declared type
`CustomType[P]`. [This is the
assignment](0980b9d9ab/src/async_utils/gen_transform.py (L108))
that I'm referring to which then leads to error in downstream usage.
Pyright and mypy does seem to use the declared type.
There are multiple diagnostics in `dd-trace-py` that requires support
for `cls`.
I'm seeing `Divergent` type for an example like which ~~I'm not sure
why, I'll look into it tomorrow~~ is because of a cycle as mentioned in
https://github.com/astral-sh/ty/issues/1729#issuecomment-3612279974:
```py
from typing import Callable
def decorator[**P](c: Callable[P, int]) -> Callable[P, str]: ...
@decorator
def func(a: int) -> int: ...
# ((a: int) -> str) | ((a: Divergent) -> str)
reveal_type(func)
```
I ~~need to look into why are the parameters not being specialized
through multiple decorators in the following code~~ think this is also
because of the cycle mentioned in
https://github.com/astral-sh/ty/issues/1729#issuecomment-3612279974 and
the fact that we don't support `staticmethod` properly:
```py
from contextlib import contextmanager
class Foo:
@staticmethod
@contextmanager
def method(x: int):
yield
foo = Foo()
# ty: Revealed type: `() -> _GeneratorContextManager[Unknown, None, None]` [revealed-type]
reveal_type(foo.method)
```
There's some issue related to `Protocol` that are generic over a
`ParamSpec` in `starlette` which might be related to
https://github.com/astral-sh/ty/issues/1635 but I'm not sure. Here's a
minimal example to reproduce:
<details><summary>Code snippet:</summary>
<p>
```py
from collections.abc import Awaitable, Callable, MutableMapping
from typing import Any, Callable, ParamSpec, Protocol
P = ParamSpec("P")
Scope = MutableMapping[str, Any]
Message = MutableMapping[str, Any]
Receive = Callable[[], Awaitable[Message]]
Send = Callable[[Message], Awaitable[None]]
ASGIApp = Callable[[Scope, Receive, Send], Awaitable[None]]
_Scope = Any
_Receive = Callable[[], Awaitable[Any]]
_Send = Callable[[Any], Awaitable[None]]
# Since `starlette.types.ASGIApp` type differs from `ASGIApplication` from `asgiref`
# we need to define a more permissive version of ASGIApp that doesn't cause type errors.
_ASGIApp = Callable[[_Scope, _Receive, _Send], Awaitable[None]]
class _MiddlewareFactory(Protocol[P]):
def __call__(
self, app: _ASGIApp, *args: P.args, **kwargs: P.kwargs
) -> _ASGIApp: ...
class Middleware:
def __init__(
self, factory: _MiddlewareFactory[P], *args: P.args, **kwargs: P.kwargs
) -> None:
self.factory = factory
self.args = args
self.kwargs = kwargs
class ServerErrorMiddleware:
def __init__(
self,
app: ASGIApp,
value: int | None = None,
flag: bool = False,
) -> None:
self.app = app
self.value = value
self.flag = flag
async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None: ...
# ty: Argument to bound method `__init__` is incorrect: Expected `_MiddlewareFactory[(...)]`, found `<class 'ServerErrorMiddleware'>` [invalid-argument-type]
Middleware(ServerErrorMiddleware, value=500, flag=True)
```
</p>
</details>
### Conformance analysis
> ```diff
> -constructors_callable.py:36:13: info[revealed-type] Revealed type:
`(...) -> Unknown`
> +constructors_callable.py:36:13: info[revealed-type] Revealed type:
`(x: int) -> Unknown`
> ```
Requires return type inference i.e.,
https://github.com/astral-sh/ruff/pull/21551
> ```diff
> +constructors_callable.py:194:16: error[invalid-argument-type]
Argument is incorrect: Expected `list[T@__init__]`, found `list[Unknown
| str]`
> +constructors_callable.py:194:22: error[invalid-argument-type]
Argument is incorrect: Expected `list[T@__init__]`, found `list[Unknown
| str]`
> +constructors_callable.py:195:4: error[invalid-argument-type] Argument
is incorrect: Expected `list[T@__init__]`, found `list[Unknown | int]`
> +constructors_callable.py:195:9: error[invalid-argument-type] Argument
is incorrect: Expected `list[T@__init__]`, found `list[Unknown | str]`
> ```
I might need to look into why this is happening...
> ```diff
> +generics_defaults.py:79:1: error[type-assertion-failure] Type
`type[Class_ParamSpec[(str, int, /)]]` does not match asserted type
`<class 'Class_ParamSpec'>`
> ```
which is on the following code
```py
DefaultP = ParamSpec("DefaultP", default=[str, int])
class Class_ParamSpec(Generic[DefaultP]): ...
assert_type(Class_ParamSpec, type[Class_ParamSpec[str, int]])
```
It's occurring because there's no equivalence relationship defined
between `ClassLiteral` and `KnownInstanceType::TypeGenericAlias` which
is what these types are.
Everything else looks good to me!
When converting a class (whether specialized or not) into a `Callable`
type, we should carry through any generic context that the constructor
has. This includes both the generic context of the class itself (if it's
generic) and of the constructor methods (if they are separately
generic).
To help test this, this also updates the `generic_context` extension
function to work on `Callable` types and unions; and adds a new
`into_callable` extension function that works just like
`CallableTypeOf`, but on value forms instead of type forms.
Pulled this out of #21551 for separate review.
## Summary
Closes https://github.com/astral-sh/ty/issues/957
As explained in https://github.com/astral-sh/ty/issues/957, literal
union types for recursively defined values can be widened early to
speed up the convergence of fixed-point iterations.
This PR achieves this by embedding a marker in `UnionType` that
distinguishes whether a value is recursively defined.
This also allows us to identify values that are not recursively
defined, so I've increased the limit on the number of elements in a
literal union type for such values.
Edit: while this PR doesn't provide the significant performance
improvement initially hoped for, it does have the benefit of allowing
the number of elements in a literal union to be raised above the salsa
limit, and indeed mypy_primer results revealed that a literal union of
220 elements was actually being used.
## Test Plan
`call/union.md` has been updated
Fixes https://github.com/astral-sh/ty/issues/1587
## Summary
Perform cycle normalization on typevar bounds and constraints (similar
to how it was already done for typevar defaults) in order to ensure
convergence in cyclic cases.
There might be another fix here that could avoid the cycle in many more
cases, where we don't eagerly evaluate typevar bounds/constraints on
explicit specialization, but just accept the given specialization and
later evaluate to see whether we need to emit a diagnostic on it. But
the current fix here is sufficient to solve the problem and matches the
patterns we use to ensure cycle convergence elsewhere, so it seems good
for now; left a TODO for the other idea.
This fix is sufficient to make us not panic, but not sufficient to get
the semantics fully correct; see the TODOs in the tests. I have ideas
for fixing that as well, but it seems worth at least getting this in to
fix the panic.
## Test Plan
Test that previously panicked now does not.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
This makes auto-import include modules in suggestions.
In this initial implementation, we permit this to include submodules as
well. This is in contrast to what we do in `import ...` completions.
It's easy to change this behavior, but I think it'd be interesting to
run with this for now to see how well it works.
The existing importer functionality always required
an import request with a module and a member in that
module. But we want to be able to insert import statements
for a module itself and not any members in the module.
This is basically changing `member: &str` to an
`Option<&str>` and fixing the fallout in a way that
makes sense for module-only imports.
I think changes to this value are generally noise. It's hard to tell
what it means and it isn't especially actionable. We already have an
eval running in CI for completion ranking, so I don't think it's
terribly important to care about ranking here in e2e tests _generally_.
A completion lacking a module reference doesn't necessarily mean that
the symbol is defined within the current module. I believe the intent
here is that it means that no import is required to use it.
These are all improvements here with one slight regression on
`reveal_type` ranking. The previous completions offered were:
```
$ cargo r -q -p ty_completion_eval show-one ty-extensions-lower-stdlib
ENOTRECOVERABLE (module: errno)
REG_WHOLE_HIVE_VOLATILE (module: winreg)
SQLITE_NOTICE_RECOVER_WAL (module: _sqlite3)
SupportsGetItemViewable (module: _typeshed)
removeHandler (module: unittest.signals)
reveal_mro (module: ty_extensions)
reveal_protocol_interface (module: ty_extensions)
reveal_type (module: typing) (*, 8/10)
_remove_original_values (module: _osx_support)
_remove_universal_flags (module: _osx_support)
-----
found 10 completions
```
And now they are:
```
$ cargo r -q -p ty_completion_eval show-one ty-extensions-lower-stdlib
ENOTRECOVERABLE (module: errno)
REG_WHOLE_HIVE_VOLATILE (module: winreg)
SQLITE_NOTICE_RECOVER_WAL (module: sqlite3)
SQLITE_NOTICE_RECOVER_WAL (module: sqlite3.dbapi2)
removeHandler (module: unittest)
removeHandler (module: unittest.signals)
reveal_mro (module: ty_extensions)
reveal_protocol_interface (module: ty_extensions)
reveal_type (module: typing) (*, 9/9)
-----
found 9 completions
```
Some completions were removed (because they are now considered
unexported) and some were added (likely do to better re-export support).
This particular case probably warrants more special attention anyway.
So I think this is fine. (It's only a one-ranking regression.)
This applies recursively. So if *any* component of a module name starts
with a `_`, then symbols from that module are excluded from auto-import.
The exception is when it's a module within first party code. Then we
want to include it in auto-import.
Note that the `Deprecated` symbols from `importlib.metadata` are no
longer offered because 1) `importlib.metadata` defined `__all__` and 2)
the `Deprecated` symbols aren't in it. These seem to not be a part of
its public API according to the docs, so this seems right to me.
This commit (mostly) re-implements the support for `__all__` in
ty-proper, but inside the auto-import AST scanner.
When `__all__` isn't present in a module, we fall back to conventions to
determine whether a symbol is exported or not:
https://docs.python.org/3/library/index.html
However, in keeping with current practice for non-auto-import
completions, we continue to provide sunder and dunder names as
re-exports.
When `__all__` is present, we respect it strictly. That is, a symbol is
exported *if and only if* it's in `__all__`. This is somewhat stricter
than pylance seemingly is. I felt like it was a good idea to start here,
and we can relax it based on user demand (perhaps through a setting).
This simplifies the existing visitor by DRYing it up slightly.
We also add tests for the existing functionality. In particular,
we want to add support for re-export conventions, and that
warrants more careful testing.
## Summary
I realized we don't really test `DefinitionKind::ImportFromSubmodule` in
the IDE at all, so here's a bunch of them, just recording our current
behaviour.
## Test Plan
*stares at the camera*
## Summary
I have no idea what I'm doing with the fix (all the interesting stuff is
in the second commit).
The basic problem is the compiler emits the diagnostic:
```
x: "foobar"
^^^^^^
```
Which the suppression code-action hands the end of to `Tokens::after`
which then panics because that function panics if handed an offset that
is in the middle of a token.
Fixes https://github.com/astral-sh/ty/issues/1748
## Test Plan
Many tests added (only the e2e test matters).
## Summary
This makes an importing file a required argument to module resolution,
and if the fast-path cached query fails to resolve the module, take the
slow-path uncached (could be cached if we want)
`desperately_resolve_module` which will walk up from the importing file
until it finds a `pyproject.toml` (arbitrary decision, we could try
every ancestor directory), at which point it takes one last desperate
attempt to use that directory as a search-path. We do not continue
walking up once we've found a `pyproject.toml` (arbitrary decision, we
could keep going up).
Running locally, this fixes every broken-for-workspace-reasons import in
pyx's workspace!
* Fixes https://github.com/astral-sh/ty/issues/1539
* Improves https://github.com/astral-sh/ty/issues/839
## Test Plan
The workspace tests see a huge improvement on most absolute imports.
Fixes https://github.com/astral-sh/ty/issues/1716.
## Test plan
I added a corpus snippet that causes us to panic on `main` (I tested by
running `cargo run -p ty_python_semantic --test=corpus` without the fix
applied).
## Summary
This PR re-implements [return-in-generator
(B901)](https://docs.astral.sh/ruff/rules/return-in-generator/#return-in-generator-b901)
for async generators as a semantic syntax error. This is not a syntax
error for sync generators, so we'll need to preserve both the lint rule
and the syntax error in this case.
It also updates B901 and the new implementation to catch cases where the
generator's `yield` or `yield from` expression is part of another
statement, as in:
```py
def foo():
return (yield)
```
These were previously not caught because we only looked for
`Stmt::Expr(Expr::Yield)` in `visit_stmt` instead of visiting `yield`
expressions directly. I think this modification is within the spirit of
the rule and safe to try out since the rule is in preview.
## Test Plan
<!-- How was it tested? -->
I have written tests as directed in #17412
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
Signed-off-by: 11happy <bhuminjaysoni@gmail.com>
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
## Summary
Star-imports can not just affect the state of symbols that they pull in,
they can also affect the state of members that are associated with those
symbols. For example, if `obj.attr` was previously narrowed from `int |
None` to `int`, and a star-import now overwrites `obj`, then the
narrowing on `obj.attr` should be "reset".
This PR keeps track of the state of associated members during star
imports and properly models the flow of their corresponding state
through the control flow structure that we artificially create for
star-imports.
See [this
comment](https://github.com/astral-sh/ty/issues/1355#issuecomment-3607125005)
for an explanation why this caused ty to see certain `asyncio` symbols
as not being accessible on Python 3.14.
closes https://github.com/astral-sh/ty/issues/1355
## Ecosystem impact
```diff
async-utils (https://github.com/mikeshardmind/async-utils)
- src/async_utils/bg_loop.py:115:31: error[invalid-argument-type] Argument to bound method `set_task_factory` is incorrect: Expected `_TaskFactory | None`, found `def eager_task_factory[_T_co](loop: AbstractEventLoop | None, coro: Coroutine[Any, Any, _T_co@eager_task_factory], *, name: str | None = None, context: Context | None = None) -> Task[_T_co@eager_task_factory]`
- Found 30 diagnostics
+ Found 29 diagnostics
mitmproxy (https://github.com/mitmproxy/mitmproxy)
+ mitmproxy/utils/asyncio_utils.py:96:60: warning[unused-ignore-comment] Unused blanket `type: ignore` directive
- test/conftest.py:37:31: error[invalid-argument-type] Argument to bound method `set_task_factory` is incorrect: Expected `_TaskFactory | None`, found `def eager_task_factory[_T_co](loop: AbstractEventLoop | None, coro: Coroutine[Any, Any, _T_co@eager_task_factory], *, name: str | None = None, context: Context | None = None) -> Task[_T_co@eager_task_factory]`
```
All of these seem to be correct, they give us a different type for
`asyncio` symbols that are now imported from different
`sys.version_info` branches (where we previously failed to recognize
some of these as statically true/false).
```diff
dd-trace-py (https://github.com/DataDog/dd-trace-py)
- ddtrace/contrib/internal/asyncio/patch.py:39:12: error[invalid-argument-type] Argument to function `unwrap` is incorrect: Expected `WrappedFunction`, found `def create_task[_T](self, coro: Coroutine[Any, Any, _T@create_task] | Generator[Any, None, _T@create_task], *, name: object = None) -> Task[_T@create_task]`
+ ddtrace/contrib/internal/asyncio/patch.py:39:12: error[invalid-argument-type] Argument to function `unwrap` is incorrect: Expected `WrappedFunction`, found `def create_task[_T](self, coro: Generator[Any, None, _T@create_task] | Coroutine[Any, Any, _T@create_task], *, name: object = None) -> Task[_T@create_task]`
```
Similar, but only results in a diagnostic change.
## Test Plan
Added a regression test
This fixes a non-determinism that we were seeing in the constraint set
tests in https://github.com/astral-sh/ruff/pull/21715.
In this test, we create the following constraint set, and then try to
create a specialization from it:
```
(T@constrained_by_gradual_list = list[Base])
∨
(Bottom[list[Any]] ≤ T@constrained_by_gradual_list ≤ Top[list[Any]])
```
That is, `T` is either specifically `list[Base]`, or it's any `list`.
Our current heuristics say that, absent other restrictions, we should
specialize `T` to the more specific type (`list[Base]`).
In the correct test output, we end up creating a BDD that looks like
this:
```
(T@constrained_by_gradual_list = list[Base])
┡━₁ always
└─₀ (Bottom[list[Any]] ≤ T@constrained_by_gradual_list ≤ Top[list[Any]])
┡━₁ always
└─₀ never
```
In the incorrect output, the BDD looks like this:
```
(Bottom[list[Any]] ≤ T@constrained_by_gradual_list ≤ Top[list[Any]])
┡━₁ always
└─₀ never
```
The difference is the ordering of the two individual constraints. Both
constraints appear in the first BDD, but the second BDD only contains `T
is any list`. If we were to force the second BDD to contain both
constraints, it would look like this:
```
(Bottom[list[Any]] ≤ T@constrained_by_gradual_list ≤ Top[list[Any]])
┡━₁ always
└─₀ (T@constrained_by_gradual_list = list[Base])
┡━₁ always
└─₀ never
```
This is the standard shape for an OR of two constraints. However! Those
two constraints are not independent of each other! If `T` is
specifically `list[Base]`, then it's definitely also "any `list`". From
that, we can infer the contrapositive: that if `T` is not any list, then
it cannot be `list[Base]` specifically. When we encounter impossible
situations like that, we prune that path in the BDD, and treat it as
`false`. That rewrites the second BDD to the following:
```
(Bottom[list[Any]] ≤ T@constrained_by_gradual_list ≤ Top[list[Any]])
┡━₁ always
└─₀ (T@constrained_by_gradual_list = list[Base])
┡━₁ never <-- IMPOSSIBLE, rewritten to never
└─₀ never
```
We then would see that that BDD node is redundant, since both of its
outgoing edges point at the `never` node. Our BDDs are _reduced_, which
means we have to remove that redundant node, resulting in the BDD we saw
above:
```
(Bottom[list[Any]] ≤ T@constrained_by_gradual_list ≤ Top[list[Any]])
┡━₁ always
└─₀ never <-- redundant node removed
```
The end result is that we were "forgetting" about the `T = list[Base]`
constraint, but only for some BDD variable orderings.
To fix this, I'm leaning in to the fact that our BDDs really do need to
"remember" all of the constraints that they were created with. Some
combinations might not be possible, but we now have the sequent map,
which is quite good at detecting and pruning those.
So now our BDDs are _quasi-reduced_, which just means that redundant
nodes are allowed. (At first I was worried that allowing redundant nodes
would be an unsound "fix the glitch". But it turns out they're real!
[This](https://ieeexplore.ieee.org/abstract/document/130209) is the
paper that introduces them, though it's very difficult to read. Knuth
mentions them in §7.1.4 of
[TAOCP](https://course.khoury.northeastern.edu/csu690/ssl/bdd-knuth.pdf),
and [this paper](https://par.nsf.gov/servlets/purl/10128966) has a nice
short summary of them in §2.)
While we're here, I've added a bunch of `debug` and `trace` level log
messages to the constraint set implementation. I was getting tired of
having to add these by hands over and over. To enable them, just set
`TY_LOG` in your environment, e.g.
```sh
env TY_LOG=ty_python_semantic::types::constraints::SequentMap=trace ty check ...
```
[Note, this has an `internal` label because are still not using
`specialize_constrained` in anything user-facing yet.]
## Summary
For a type alias like the one below, where `UnknownClass` is something
with a dynamic type, we previously lost track of the fact that this
dynamic type was explicitly specialized *with a type variable*. If that
alias is then later explicitly specialized itself (`MyAlias[int]`), we
would miscount the number of legacy type variables and emit a
`invalid-type-arguments` diagnostic
([playground](https://play.ty.dev/886ae6cc-86c3-4304-a365-510d29211f85)).
```py
T = TypeVar("T")
MyAlias: TypeAlias = UnknownClass[T] | None
```
The solution implemented here is not pretty, but we can hopefully get
rid of it via https://github.com/astral-sh/ty/issues/1711. Also, once we
properly support `ParamSpec` and `Concatenate`, we should be able to
remove some of this code.
This addresses many of the `invalid-type-arguments` false-positives in
https://github.com/astral-sh/ty/issues/1685. With this change, there are
still some diagnostics of this type left. Instead of implementing even
more (rather sophisticated) workarounds for these cases as well, it
might be much easier to wait for full `ParamSpec`/`Concatenate` support
and then try again.
A disadvantage of this implementation is that we lose track of some
`@Todo` types and replace them with `Unknown`. We could spend more
effort and try to preserve them, but I'm unsure if this is the best use
of our time right now.
## Test Plan
New Markdown tests.
## Summary
Implement default-specialization of generic type aliases (implicit or
PEP-613) if they are used in a type expression without an explicit
specialization.
closes https://github.com/astral-sh/ty/issues/1690
## Typing conformance
```diff
-generics_defaults_specialization.py:26:5: error[type-assertion-failure] Type `SomethingWithNoDefaults[int, str]` does not match asserted type `SomethingWithNoDefaults[int, DefaultStrT]`
```
That's exactly what we want ✔️
All other tests in this file pass as well, with the exception of this
assertion, which is just wrong (at least according to our
interpretation, `type[Bar] != <class 'Bar'>`). I checked that we do
correctly default-specialize the type parameter which is not displayed
in the diagnostic that we raise.
```py
class Bar(SubclassMe[int, DefaultStrT]): ...
assert_type(Bar, type[Bar[str]]) # ty: Type `type[Bar[str]]` does not match asserted type `<class 'Bar'>`
```
## Ecosystem impact
Looks like I should have included this last week 😎
## Test Plan
Updated pre-existing tests and add a few new ones.
This adds a new `suppression` module to the `ruff_linter` crate, similar
to the suppression
module for ty, to parse comments for ruff suppression directives, such
as `# ruff: disable[CODE]`.
## Summary
Fixes#21750 and a related bug in `PLE1142`. We were not properly
considering generators to be valid `await` contexts, which caused the
`F704` issue. One of the tests I added for this also uncovered an issue
in `PLE1142` for comprehensions nested within async generators because
we were only checking the current scope rather than traversing the
nested context.
## Test Plan
Both of these rules are implemented as semantic syntax errors, so I
added tests (and fixes) in both Ruff and ty.
In the following example, there are two occurrences of `typing.Self`,
one for `Foo.foo` and one for `Bar.bar`:
```py
from typing import Self, reveal_type
class Foo[T]:
def foo(self: Self) -> T:
raise NotImplementedError
class Bar:
def bar(self: Self, x: Foo[Self]):
# SHOULD BE: bound method Foo[Self@bar].foo() -> Self@bar
# revealed: bound method Foo[Self@bar].foo() -> Foo[Self@bar]
reveal_type(x.foo)
def f[U: Bar](x: Foo[U]):
# revealed: bound method Foo[U@f].foo() -> U@f
reveal_type(x.foo)
```
When accessing a bound method, we replace any occurrences of `Self` with
the bound `self` type.
We were doing this correctly for the second reveal. We would first apply
the specialization, getting `(self: Self@foo) -> U@F` as the signature
of `x.foo`. We would then bind the `self` parameter, substituting
`Self@foo` with `Foo[U@F]` as part of that. The return type was already
specialized to `U@F`, so that substitution had no further affect on the
type that we revealed.
In the first reveal, we would follow the same process, but we confused
the two occurrences of `Self`. We would first apply the specialization,
getting `(self: Self@foo) -> Self@bar` as the method signature. We would
then try to bind the `self` parameter, substituting `Self@foo` with
`Foo[Self@bar]`. However, because we didn't distinguish the two separate
`Self`s, and applied the substitution to the return type as well as to
the `self` parameter.
The fix is to track which particular `Self` we're trying to substitute
when applying the type mapping.
Fixes https://github.com/astral-sh/ty/issues/1713
Here are a bunch of (variously failing and passing) mdtests that reflect
the kinds of issues people encounter when running ty over an entire
workspace without sufficient hand-holding (especially because in the IDE
it is unclear *how* to provide that hand-holding).
The `Display` implementation for constraint sets is brittle, and
deserves a rethink. But later! It's perfectly fine for printf debugging;
we just shouldn't be writing mdtests that depend on any particular
rendering details. Most of these tests can be replaced with an
equivalence check that actually validates that the _behavior_ of two
constraint sets are identical.
## Summary
Fixes false positives in SIM222 and SIM223 where truthiness was
incorrectly assumed for `tuple(x)`, `list(x)`, `set(x)` when `x` is not
iterable.
Fixes#21473.
## Problem
`Truthiness::from_expr` recursively called itself on arguments to
iterable initializers (`tuple`, `list`, `set`) without checking if the
argument is iterable, causing false positives for cases like `tuple(0)
or True` and `tuple("") or True`.
## Approach
Added `is_definitely_not_iterable` helper and updated
`Truthiness::from_expr` to return `Unknown` for non-iterable arguments
(numbers, booleans, None) and string literals when called with iterable
initializers, preventing incorrect truthiness assumptions.
## Test Plan
Added test cases to `SIM222.py` and `SIM223.py` for `tuple("")`,
`tuple(0)`, `tuple(1)`, `tuple(False)`, and `tuple(None)` with `or True`
and `and False` patterns.
---------
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
## Summary
Marks fixes as unsafe when they change return types (`None` → `Path`,
`str`/`bytes` → `Path`, `str` → `Path`), except when the call is a
top-level expression.
Fixes#21431.
## Problem
Fixes for `os.rename`, `os.replace`, `os.getcwd`/`os.getcwdb`, and
`os.readlink` were marked safe despite changing return types, which can
break code that uses the return value.
## Approach
Added `is_top_level_expression_call` helper to detect when a call is a
top-level expression (return value unused). Updated
`check_os_pathlib_two_arg_calls` and `check_os_pathlib_single_arg_calls`
to mark fixes as unsafe unless the call is a top-level expression.
Updated PTH109 to use the helper for applicability determination.
## Test Plan
Updated snapshots for `preview_full_name.py`, `preview_import_as.py`,
`preview_import_from.py`, and `preview_import_from_as.py` to reflect
unsafe markers.
---------
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
Previously, the code action to do auto-import on a pre-existing symbol
assumed that the auto-importer would always generate an import
statement. But sometimes an import statement already exists.
A good example of this is the following snippet:
```
import warnings
@deprecated
def myfunc(): pass
```
Specifically, `deprecated` exists in `warnings` but isn't currently
imported. A code action to fix this could feasibly do two
transformations here. One is:
```
import warnings
@warnings.deprecated
def myfunc(): pass
```
Another is:
```
from warnings import deprecated
import warnings
@deprecated
def myfunc(): pass
```
The existing auto-import infrastructure chooses the former, since it
reuses a pre-existing import statement. But this PR chooses the latter
for the case of a code action. I'm not 100% sure this is the correct
choice, but it seems to defer more strongly to what the user has typed.
That is, that they want to use it unqualified because it's what has been
typed. So we should add the necessary import statement to make that
work.
Fixesastral-sh/ty#1668
This works by adding a third module resolution mode that lets the caller
opt into _some_ shadowing of modules that is otherwise not allowed (for
`typing` and `typing_extensions`).
Fixesastral-sh/ty#1658
## Summary
If you manage to create an `typing.GenericAlias` instance without us
knowing how that was created, then we don't know what to do with this in
a type annotation. So it's better to be explicit and show an error
instead of failing silently with a `@Todo` type.
## Test Plan
* New Markdown tests
* Zero ecosystem impact
## Summary
We had tests for this already, but they used generic classes that were
bivariant in their type parameter, and so this case wasn't captured.
closes https://github.com/astral-sh/ty/issues/1702
## Test Plan
Updated Markdown tests
## Summary
These projects from `mypy_primer` were missing from both `good.txt` and
`bad.txt` for some reason. I thought about writing a script that would
verify that `good.txt` + `bad.txt` = `mypy_primer.projects`, but that's
not completely trivial since there are projects like `cpython` only
appear once in `good.txt`. Given that we can hopefully soon get rid of
both of these files (and always run on all projects), it's probably not
worth the effort. We are usually notified of all `mypy_primer` changes.
## Test Plan
CI on this PR
## Summary
The exact behavior around what's allowed vs. disallowed was partly
detected through trial and error in the runtime.
I was a little confused by [this
comment](https://github.com/python/cpython/pull/129352) that says
"`NamedTuple` subclasses cannot be inherited from" because in practice
that doesn't appear to error at runtime.
Closes [#1683](https://github.com/astral-sh/ty/issues/1683).
## Summary
This is another small refactor for
https://github.com/astral-sh/ruff/pull/21445 that splits the single
`paramspec.md` into `generics/legacy/paramspec.md` and
`generics/pep695/paramspec.md`.
## Test Plan
Make sure that all mdtests pass.
2025-11-29 06:49:39 +00:00
2071 changed files with 105920 additions and 38814 deletions
- Consolidate diagnostics for matched disable/enable suppression comments ([#22099](https://github.com/astral-sh/ruff/pull/22099))
- Report diagnostics for invalid/unmatched range suppression comments ([#21908](https://github.com/astral-sh/ruff/pull/21908))
- \[`airflow`\] Passing positional argument into `airflow.lineage.hook.HookLineageCollector.create_asset` is not allowed (`AIR303`) ([#22046](https://github.com/astral-sh/ruff/pull/22046))
- \[`refurb`\] Mark `FURB192` fix as always unsafe ([#22210](https://github.com/astral-sh/ruff/pull/22210))
- Fix GitHub format for multi-line diagnostics ([#22108](https://github.com/astral-sh/ruff/pull/22108))
- \[`flake8-unused-arguments`\] Mark `**kwargs` in `TypeVar` as used (`ARG001`) ([#22214](https://github.com/astral-sh/ruff/pull/22214))
### Rule changes
- Add `help:` subdiagnostics for several Ruff rules that can sometimes appear to disagree with `ty` ([#22331](https://github.com/astral-sh/ruff/pull/22331))
- \[`pylint`\] Demote `PLW1510` fix to display-only ([#22318](https://github.com/astral-sh/ruff/pull/22318))
- \[`pylint`\] Ignore identical members (`PLR1714`) ([#22220](https://github.com/astral-sh/ruff/pull/22220))
- \[`pylint`\] Improve diagnostic range for `PLC0206` ([#22312](https://github.com/astral-sh/ruff/pull/22312))
- \[`ruff`\] Improve fix title for `RUF102` invalid rule code ([#22100](https://github.com/astral-sh/ruff/pull/22100))
- \[`flake8-simplify`\]: Avoid unnecessary builtins import for `SIM105` ([#22358](https://github.com/astral-sh/ruff/pull/22358))
### Configuration
- Allow Python 3.15 as valid `target-version` value in preview ([#22419](https://github.com/astral-sh/ruff/pull/22419))
- Check `required-version` before parsing rules ([#22410](https://github.com/astral-sh/ruff/pull/22410))
- Include configured `src` directories when resolving graphs ([#22451](https://github.com/astral-sh/ruff/pull/22451))
### Documentation
- Update `T201` suggestion to not use root logger to satisfy `LOG015` ([#22059](https://github.com/astral-sh/ruff/pull/22059))
- Fix `iter` example in unsafe fixes doc ([#22118](https://github.com/astral-sh/ruff/pull/22118))
- \[`flake8_print`\] better suggestion for `basicConfig` in `T201` docs ([#22101](https://github.com/astral-sh/ruff/pull/22101))
- \[`pylint`\] Restore the fix safety docs for `PLW0133` ([#22211](https://github.com/astral-sh/ruff/pull/22211))
- Fix Jupyter notebook discovery info for editors ([#22447](https://github.com/astral-sh/ruff/pull/22447))
- [formatter] Fluent formatting of method chains ([#21369](https://github.com/astral-sh/ruff/pull/21369))
- [formatter] Keep lambda parameters on one line and parenthesize the body if it expands ([#21385](https://github.com/astral-sh/ruff/pull/21385))
- \[`flake8-implicit-str-concat`\] New rule to prevent implicit string concatenation in collections (`ISC004`) ([#21972](https://github.com/astral-sh/ruff/pull/21972))
- \[`flake8-use-pathlib`\] Make fixes unsafe when types change in compound statements (`PTH104`, `PTH105`, `PTH109`, `PTH115`) ([#22009](https://github.com/astral-sh/ruff/pull/22009))
- \[`refurb`\] Extend support for `Path.open` (`FURB101`, `FURB103`) ([#21080](https://github.com/astral-sh/ruff/pull/21080))
### Bug fixes
- \[`pyupgrade`\] Fix parsing named Unicode escape sequences (`UP032`) ([#21901](https://github.com/astral-sh/ruff/pull/21901))
### Rule changes
- \[`eradicate`\] Ignore `ruff:disable` and `ruff:enable` comments in `ERA001` ([#22038](https://github.com/astral-sh/ruff/pull/22038))
- \[`flake8-pytest-style`\] Allow `match` and `check` keyword arguments without an expected exception type (`PT010`) ([#21964](https://github.com/astral-sh/ruff/pull/21964))
- [syntax-errors] Annotated name cannot be global ([#20868](https://github.com/astral-sh/ruff/pull/20868))
### Documentation
- Add `uv` and `ty` to the Ruff README ([#21996](https://github.com/astral-sh/ruff/pull/21996))
- Document known lambda formatting deviations from Black ([#21954](https://github.com/astral-sh/ruff/pull/21954))
- \[`flake8-bugbear`\] Catch `yield` expressions within other statements (`B901`) ([#21200](https://github.com/astral-sh/ruff/pull/21200))
- \[`flake8-use-pathlib`\] Mark fixes unsafe for return type changes (`PTH104`, `PTH105`, `PTH109`, `PTH115`) ([#21440](https://github.com/astral-sh/ruff/pull/21440))
This repository contains both Ruff (a Python linter and formatter) and ty (a Python type checker). The crates follow a naming convention: `ruff_*` for Ruff-specific code and `ty_*` for ty-specific code. ty reuses several Ruff crates, including the Python parser (`ruff_python_parser`) and AST definitions (`ruff_python_ast`).
## Running Tests
Run all tests (using `nextest` for faster execution):
```sh
cargo nextest run
```
For faster test execution, use the `fast-test` profile which enables optimizations while retaining debug info:
```sh
cargo nextest run --cargo-profile fast-test
```
Run tests for a specific crate:
```sh
cargo nextest run -p ty_python_semantic
```
Run a specific mdtest (use a substring of the test name):
```sh
MDTEST_TEST_FILTER="<filter>" cargo nextest run -p ty_python_semantic mdtest
Use debug builds (not `--release`) when developing, as release builds lack debug assertions and have slower compile times.
Run Ruff:
```sh
cargo run --bin ruff -- check path/to/file.py
```
Run ty:
```sh
cargo run --bin ty -- check path/to/file.py
```
## Pull Requests
When working on ty, PR titles should start with `[ty]` and be tagged with the `ty` GitHub label.
## Development Guidelines
- All changes must be tested. If you're not testing your changes, you're not done.
- Get your tests to pass. If you didn't run the tests, your code does not work.
- Follow existing code style. Check neighboring files for patterns.
- Always run `uvx prek run -a` at the end of a task.
- Avoid writing significant amounts of new code. This is often a sign that we're missing an existing method or mechanism that could help solve the problem. Look for existing utilities first.
- Avoid falling back to patterns that require `panic!`, `unreachable!`, or `.unwrap()`. Instead, try to encode those constraints in the type system.
- Prefer let chains (`if let` combined with `&&`) over nested `if let` statements to reduce indentation and improve readability.
RUFF_UPDATE_SCHEMA=1 cargo test# Rust testing and updating ruff.schema.json
uvx pre-commit run --all-files --show-diff-on-failure# Rust and Python formatting, Markdown and Python linting, etc.
uvx prek run -a# Rust and Python formatting, Markdown and Python linting, etc.
```
These checks will run on GitHub Actions when you open your pull request, but running them locally
@@ -331,13 +331,6 @@ you addressed them.
## MkDocs
> [!NOTE]
>
> The documentation uses Material for MkDocs Insiders, which is closed-source software.
> This means only members of the Astral organization can preview the documentation exactly as it
> will appear in production.
> Outside contributors can still preview the documentation, but there will be some differences. Consult [the Material for MkDocs documentation](https://squidfunk.github.io/mkdocs-material/insiders/benefits/#features) for which features are exclusively available in the insiders version.
To preview any changes to the documentation locally:
1. Install the [Rust toolchain](https://www.rust-lang.org/tools/install).
@@ -351,11 +344,7 @@ To preview any changes to the documentation locally:
Some files were not shown because too many files have changed in this diff
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