This PR adds the new **_constraint implication_** relationship between
types, aka `is_subtype_of_given`, which tests whether one type is a
subtype of another _assuming that the constraints in a particular
constraint set hold_.
For concrete types, constraint implication is exactly the same as
subtyping. (A concrete type is any fully static type that is not a
typevar. It can _contain_ a typevar, though — `list[T]` is considered
concrete.)
The interesting case is typevars. The other typing relationships (TODO:
will) all "punt" on the question when considering a typevar, by
translating the desired relationship into a constraint set. At some
point, though, we need to resolve a constraint set; at that point, we
can no longer punt on the question. Unlike with concrete types, the
answer will depend on the constraint set that we are considering.
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR refactors semantic error tests in each seperate file
## Test Plan
<!-- How was it tested? -->
## CC
- @ntBre
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
Summary
--
Fixes#19550
This PR copies our non-watch diagnostic rendering code into
`Printer::write_continuously` in preview mode, allowing it to use
whatever output format is passed in.
I initially marked this as also fixing #19552, but I guess that's not
true currently but will be true once this is stabilized and we can
remove the warning.
Test Plan
--
Existing tests, but I don't think we have any `watch` tests, so some
manual testing as well. The default with just `ruff check --watch` is
still `concise`, adding just `--preview` still gives the `full` output,
and then specifying any other output format works, with JSON as one
example:
<img width="695" height="719" alt="Screenshot 2025-10-27 at 9 21 41 AM"
src="https://github.com/user-attachments/assets/98957911-d216-4fc4-8b6c-22c56c963b3f"
/>
When formatting clause headers for clauses that are not their own node,
like an `else` clause or `finally` clause, we begin searching for the
keyword at the end of the previous statement. However, if the previous
statement ended in a semicolon this caused a panic because we only
expected trivia between the end of the last statement and the keyword.
This PR adjusts the starting point of our search for the keyword to
begin after the optional semicolon in these cases.
Closes#21065
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## Summary
Add docstring sections which were missing from the numpy list as pointed
out here #20923. For now these are only the official sections as
documented
[here](https://numpydoc.readthedocs.io/en/latest/format.html#sections).
## Test Plan
Added a test case for DOC102
## Summary
Fixes#20973 (`docstring-extraneous-exception`) false positive when
exceptions mentioned in docstrings are caught and explicitly re-raised
using `raise e` or `raise e from None`.
## Problem Analysis
The DOC502 rule was incorrectly flagging exceptions mentioned in
docstrings as "not explicitly raised" when they were actually being
explicitly re-raised through exception variables bound in `except`
clauses.
**Root Cause**: The `BodyVisitor` in `check_docstring.rs` only checked
for direct exception references (like `raise OSError()`) but didn't
recognize when a variable bound to an exception in an `except` clause
was being re-raised.
**Example of the bug**:
```python
def f():
"""Do nothing.
Raises
------
OSError
If the OS errors.
"""
try:
pass
except OSError as e:
raise e # This was incorrectly flagged as not explicitly raising OSError
```
The issue occurred because `resolve_qualified_name(e)` couldn't resolve
the variable `e` to a qualified exception name, since `e` is just a
variable binding, not a direct reference to an exception class.
## Approach
Modified the `BodyVisitor` in
`crates/ruff_linter/src/rules/pydoclint/rules/check_docstring.rs` to:
1. **Track exception variable bindings**: Added `exception_variables`
field to map exception variable names to their exception types within
`except` clauses
2. **Enhanced raise statement detection**: Updated `visit_stmt` to check
if a `raise` statement uses a variable name that's bound to an exception
in the current `except` clause
3. **Proper scope management**: Clear exception variable mappings when
leaving `except` handlers to prevent cross-contamination
**Key changes**:
- Added `exception_variables: FxHashMap<&'a str, QualifiedName<'a>>` to
track variable-to-exception mappings
- Enhanced `visit_except_handler` to store exception variable bindings
when entering `except` clauses
- Modified `visit_stmt` to check for variable-based re-raising: `raise
e` → lookup `e` in `exception_variables`
- Clear mappings when exiting `except` handlers to maintain proper scope
---------
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
That PR title might be a bit inscrutable.
Consider the two constraints `T ≤ bool` and `T ≤ int`. Since `bool ≤
int`, by transitivity `T ≤ bool` implies `T ≤ int`. (Every type that is
a subtype of `bool` is necessarily also a subtype of `int`.) That means
that `T ≤ bool ∧ T ≰ int` is an impossible combination of constraints,
and is therefore not a valid input to any BDD. We say that that
assignment is not in the _domain_ of the BDD.
The implication `T ≤ bool → T ≤ int` can be rewritten as `T ≰ bool ∨ T ≤
int`. (That's the definition of implication.) If we construct that
constraint set in an mdtest, we should get a constraint set that is
always satisfiable. Previously, that constraint set would correctly
_display_ as `always`, but a `static_assert` on it would fail.
The underlying cause is that our `is_always_satisfied` method would only
test if the BDD was the `AlwaysTrue` terminal node. `T ≰ bool ∨ T ≤ int`
does not simplify that far, because we purposefully keep around those
constraints in the BDD structure so that it's easier to compare against
other BDDs that reference those constraints.
To fix this, we need a more nuanced definition of "always satisfied".
Instead of evaluating to `true` for _every_ input, we only need it to
evaluate to `true` for every _valid_ input — that is, every input in its
domain.
## Summary
implement pylint rule stop-iteration-return / R1708
## Test Plan
<!-- How was it tested? -->
---------
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
* Extend `airflow.models.Param` to include `airflow.models.param.Param`
case and include both `airflow.models.param.ParamDict` and
`airflow.models.param.DagParam` and their `airflow.models.` counter part
## Test Plan
<!-- How was it tested? -->
update the text fixture accordingly and reorganize them in the third
commit
Summary
--
Inspired by #20859, this PR adds the version a rule was added, and the
file and line where it was defined, to `ViolationMetadata`. The file and
line just use the standard `file!` and `line!` macros, while the more
interesting version field uses a new `violation_metadata` attribute
parsed by our `ViolationMetadata` derive macro.
I moved the commit modifying all of the rule files to the end, so it
should be a lot easier to review by omitting that one.
As a curiosity and a bit of a sanity check, I also plotted the rule
numbers over time:
<img width="640" height="480" alt="image"
src="https://github.com/user-attachments/assets/75b0b5cc-3521-4d40-a395-8807e6f4925f"
/>
I think this looks pretty reasonable and avoids some of the artifacts
the earlier versions of the script ran into, such as the `rule`
sub-command not being available or `--explain` requiring a file
argument.
<details><summary>Script and summary data</summary>
```shell
gawk --csv '
NR > 1 {
split($2, a, ".")
major = a[1]; minor = a[2]; micro = a[3]
# sum the number of rules added per minor version
versions[minor] += 1
}
END {
tot = 0
for (i = 0; i <= 14; i++) {
tot += versions[i]
print i, tot
}
}
' ruff_rules_metadata.csv > summary.dat
```
```
0 696
1 768
2 778
3 803
4 822
5 848
6 855
7 865
8 893
9 915
10 916
11 924
12 929
13 932
14 933
```
</details>
Test Plan
--
I built and viewed the documentation locally, and it looks pretty good!
<img width="1466" height="676" alt="image"
src="https://github.com/user-attachments/assets/5e227df4-7294-4d12-bdaa-31cac4e9ad5c"
/>
The spacing seems a bit awkward following the `h1` at the top, so I'm
wondering if this might look nicer as a footer in Ruff. The links work
well too:
- [v0.0.271](https://github.com/astral-sh/ruff/releases/tag/v0.0.271)
- [Related
issues](https://github.com/astral-sh/ruff/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20airflow-variable-name-task-id-mismatch)
- [View
source](https://github.com/astral-sh/ruff/blob/main/crates%2Fruff_linter%2Fsrc%2Frules%2Fairflow%2Frules%2Ftask_variable_name.rs#L34)
The last one even works on `main` now since it points to the
`derive(ViolationMetadata)` line.
In terms of binary size, this branch is a bit bigger than main with
38,654,520 bytes compared to 38,635,728 (+20 KB). I guess that's not
_too_ much of an increase, but I wanted to check since we're generating
a lot more code with macros.
---------
Co-authored-by: GiGaGon <107241144+MeGaGiGaGon@users.noreply.github.com>
## Summary
Infer a type of `Self` for unannotated `self` parameters in methods of
classes.
part of https://github.com/astral-sh/ty/issues/159
closes https://github.com/astral-sh/ty/issues/1081
## Conformance tests changes
```diff
+enums_member_values.py:85:9: error[invalid-assignment] Object of type `int` is not assignable to attribute `_value_` of type `str`
```
A true positive ✔️
```diff
-generics_self_advanced.py:35:9: error[type-assertion-failure] Argument does not have asserted type `Self@method2`
-generics_self_basic.py:14:9: error[type-assertion-failure] Argument does not have asserted type `Self@set_scale
```
Two false positives going away ✔️
```diff
+generics_syntax_infer_variance.py:82:9: error[invalid-assignment] Cannot assign to final attribute `x` on type `Self@__init__`
```
This looks like a true positive to me, even if it's not marked with `#
E` ✔️
```diff
+protocols_explicit.py:56:9: error[invalid-assignment] Object of type `tuple[int, int, str]` is not assignable to attribute `rgb` of type `tuple[int, int, int]`
```
True positive ✔️
```
+protocols_explicit.py:85:9: error[invalid-attribute-access] Cannot assign to ClassVar `cm1` from an instance of type `Self@__init__`
```
This looks like a true positive to me, even if it's not marked with `#
E`. But this is consistent with our understanding of `ClassVar`, I
think. ✔️
```py
+qualifiers_final_annotation.py:52:9: error[invalid-assignment] Cannot assign to final attribute `ID4` on type `Self@__init__`
+qualifiers_final_annotation.py:65:9: error[invalid-assignment] Cannot assign to final attribute `ID7` on type `Self@method1`
```
New true positives ✔️
```py
+qualifiers_final_annotation.py:52:9: error[invalid-assignment] Cannot assign to final attribute `ID4` on type `Self@__init__`
+qualifiers_final_annotation.py:57:13: error[invalid-assignment] Cannot assign to final attribute `ID6` on type `Self@__init__`
+qualifiers_final_annotation.py:59:13: error[invalid-assignment] Cannot assign to final attribute `ID6` on type `Self@__init__`
```
This is a new false positive, but that's a pre-existing issue on main
(if you annotate with `Self`):
https://play.ty.dev/3ee1c56d-7e13-43bb-811a-7a81e236e6ab❌ => reported
as https://github.com/astral-sh/ty/issues/1409
## Ecosystem
* There are 5931 new `unresolved-attribute` and 3292 new
`possibly-missing-attribute` attribute errors, way too many to look at
all of them. I randomly sampled 15 of these errors and found:
* 13 instances where there was simply no such attribute that we could
plausibly see. Sometimes [I didn't find it
anywhere](8644d886c6/openlibrary/plugins/openlibrary/tests/test_listapi.py (L33)).
Sometimes it was set externally on the object. Sometimes there was some
[`setattr` dynamicness going
on](a49f6b927d/setuptools/wheel.py (L88-L94)).
I would consider all of them to be true positives.
* 1 instance where [attribute was set on `obj` in
`__new__`](9e87b44fd4/sympy/tensor/array/array_comprehension.py (L45C1-L45C36)),
which we don't support yet
* 1 instance [where the attribute was defined via `__slots__`
](e250ec0fc8/lib/spack/spack/vendor/pyrsistent/_pdeque.py (L48C5-L48C14))
* I see 44 instances [of the false positive
above](https://github.com/astral-sh/ty/issues/1409) with `Final`
instance attributes being set in `__init__`. I don't think this should
block this PR.
## Test Plan
New Markdown tests.
---------
Co-authored-by: Shaygan Hooshyari <sh.hooshyari@gmail.com>
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Fixes#21017
Taught UP032’s parenthesize check to ignore underscores when inspecting
decimal integer literals so the converter emits `f"{(1_2).real}"`
instead of invalid syntax.
## Test Plan
Added test cases to UP032_2.py.
<!-- How was it tested? -->
This PR adds another useful simplification when rendering constraint
sets: `T = int` instead of `T = int ∧ T ≠ str`. (The "smaller"
constraint `T = int` implies the "larger" constraint `T ≠ str`.
Constraint set clauses are intersections, and if one constraint in a
clause implies another, we can throw away the "larger" constraint.)
While we're here, we also normalize the bounds of a constraint, so that
we equate e.g. `T ≤ int | str` with `T ≤ str | int`, and change the
ordering of BDD variables so that all constraints with the same typevar
are ordered adjacent to each other.
Lastly, we also add a new `display_graph` helper method that prints out
the full graph structure of a BDD.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
Fall back to `C[Divergent]` if we are trying to specialize `C[T]` with a
type that itself already contains deeply nested specialized generic
classes. This is a way to prevent infinite recursion for cases like
`self.x = [self.x]` where type inference for the implicit instance
attribute would not converge.
closes https://github.com/astral-sh/ty/issues/1383
closes https://github.com/astral-sh/ty/issues/837
## Test Plan
Regression tests.
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Fixes#18778
Prevent SIM911 from triggering when zip() is called on .keys()/.values()
that take any positional or keyword arguments, so Ruff
never suggests the lossy rewrite.
## Test Plan
<!-- How was it tested? -->
Added a test case to SIM911.py.
## Summary
I spun this out from #21005 because I thought it might be helpful
separately. It just renders a nice `Diagnostic` for syntax errors
pointing to the source of the error. This seemed a bit more helpful to
me than just the byte offset when working on #21005, and we had most of
the code around after #20443 anyway.
## Test Plan
This doesn't actually affect any passing tests, but here's an example of
the additional output I got when I broke the spacing after the `in`
token:
```
error[internal-error]: Expected 'in', found name
--> /home/brent/astral/ruff/crates/ruff_python_formatter/resources/test/fixtures/black/cases/cantfit.py:50:79
|
48 | need_more_to_make_the_line_long_enough,
49 | )
50 | del ([], name_1, name_2), [(), [], name_4, name_3], name_1[[name_2 for name_1 inname_0]]
| ^^^^^^^^
51 | del ()
|
```
I just appended this to the other existing output for now.
This is an alternative to #21012 that more narrowly handles this logic
in the stub-mapping machinery rather than pervasively allowing us to
identify cached files as typeshed stubs. Much of the logic is the same
(pulling the logic out of ty_server so it can be reused).
I don't have a good sense for if one approach is "better" or "worse" in
terms of like, semantics and Weird Bugs that this can cause. This one is
just "less spooky in its broad consequences" and "less muddying of
separation of concerns" and puts the extra logic on a much colder path.
I won't be surprised if one day the previous implementation needs to be
revisited for its more sweeping effects but for now this is good.
Fixes https://github.com/astral-sh/ty/issues/1054
## Summary
We currently panic in the seemingly rare case where the type of a
default value of a parameter depends on the callable itself:
```py
class C:
def f(self: C):
self.x = lambda a=self.x: a
```
Types of default values are only used for display reasons, and it's
unclear if we even want to track them (or if we should rather track the
actual value). So it didn't seem to me that we should spend a lot of
effort (and runtime) trying to achieve a theoretically correct type here
(which would be infinite).
Instead, we simply replace *nested* default types with `Unknown`, i.e.
only if the type of the default value is a callable itself.
closes https://github.com/astral-sh/ty/issues/1402
## Test Plan
Regression tests
## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR implements a new semantic syntax error where name is parameter &
global.
## Test Plan
<!-- How was it tested? -->
I have written inline test as directed in #17412
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
## Summary
Only run the "pull types" test after performing the "actual" mdtest. We
observed that the order matters. There is currently one mdtest which
panics when checked in the CLI or the playground. With this change, it
also panics in the mdtest suite.
reopens https://github.com/astral-sh/ty/issues/837?
## Summary
Implement handling of ellipsis (`...`) defaults in the `FAST002` autofix
to correctly differentiate between required and optional parameters in
FastAPI route definitions.
Previously, the autofix did not properly handle cases where parameters
used `...` as a default value (to indicate required parameters). This
could lead to incorrect transformations when applying the autofix.
This change updates the `FAST002` autofix logic to:
- Correctly recognize `...` as a valid FastAPI required default.
- Preserve the semantics of required parameters while still applying
other autofix improvements.
- Avoid incorrectly substituting or removing ellipsis defaults.
Fixes https://github.com/astral-sh/ruff/issues/20800
## Test Plan
Added a new test fixture at:
```crates/ruff_linter/resources/test/fixtures/fastapi/FAST002_2.py```
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Fixes#20941
Skip autofix for keyword and __debug__ path params
## Test Plan
<!-- How was it tested? -->
I added two test cases to
crates/ruff_linter/resources/test/fixtures/fastapi/FAST003.py.
Closes#20997
This will _decrease_ the number of diagnostics emitted for
[zip-without-explicit-strict
(B905)](https://docs.astral.sh/ruff/rules/zip-without-explicit-strict/#zip-without-explicit-strict-b905),
since previously it triggered on any `zip` call no matter the number of
arguments. It may _increase_ the number of diagnostics for
[map-without-explicit-strict
(B912)](https://docs.astral.sh/ruff/rules/map-without-explicit-strict/#map-without-explicit-strict-b912)
since it will now trigger on a single starred argument where before it
would not. However, the latter rule is in `preview` so this is
acceptable.
Note - we do not need to make any changes to
[batched-without-explicit-strict
(B911)](https://docs.astral.sh/ruff/rules/batched-without-explicit-strict/#batched-without-explicit-strict-b911)
since that just takes a single iterable.
I am doing this in one PR rather than two because we should keep the
behavior of these rules consistent with one another.
For review: apologies for the unreadability of the snapshot for `B905`.
Unfortunately I saw no way of keeping a small diff and a correct fixture
(the fixture labeled a whole block as `# Error` whereas now several in
the block became `# Ok`).Probably simplest to just view the actual
snapshot - it's relatively small.
## Summary
Make rules `INT001`, `INT002`, and `INT003` also
* trigger on qualified names when we're sure the calls are calls to the
`gettext` module. For example
```python
from gettext import gettext as foo
foo(f"{'bar'}") # very certain that this is a call to a real `gettext`
function => worth linting
```
* trigger on `builtins` bindings
```python
from builtins, gettext
gettext.install("...") # binds `gettext.gettext` to `builtins._`
builtins.__dict__["_"] = ... # also a common pattern
_(f"{'bar'}") # should therefore also be linted
```
Fixes: https://github.com/astral-sh/ruff/issues/19028
## Test Plan
Tests have been added to all three rules.
---------
Co-authored-by: Brent Westbrook <36778786+ntBre@users.noreply.github.com>
Summary
--
This PR fixes the issue I added in #20867 and noticed in #20930. Cases
like this
cause an error on any Python version:
```py
f"{1:""}"
```
which gave me a false sense of security before. Cases like this are
still
invalid only before 3.12 and weren't flagged after the changes in
#20867:
```py
f'{1: abcd "{'aa'}" }'
# ^ reused quote
f'{1: abcd "{"\n"}" }'
# ^ backslash
```
I didn't recognize these as nested interpolations that also need to be
checked
for invalid expressions, so filtering out the whole format spec wasn't
quite
right. And `elements.interpolations()` only iterates over the outermost
interpolations, not the nested ones.
There's basically no code change in this PR, I just moved the existing
check
from `parse_interpolated_string`, which parses the entire string, to
`parse_interpolated_element`. This kind of seems more natural anyway and
avoids
having to try to recursively visit nested elements after the fact in
`parse_interpolated_string`. So viewing the diff with something like
```
git diff --color-moved --ignore-space-change --color-moved-ws=allow-indentation-change main
```
should make this more clear.
Test Plan
--
New tests
## Summary
- Type checkers (and type-checker authors) think in terms of types, but
I think most Python users think in terms of values. Rather than saying
that a _type_ `X` "has no attribute `foo`" (which I think sounds strange
to many users), say that "an object of type `X` has no attribute `foo`"
- Special-case certain types so that the diagnostic messages read more
like normal English: rather than saying "Type `<class 'Foo'>` has no
attribute `bar`" or "Object of type `<class 'Foo'>` has no attribute
`bar`", just say "Class `Foo` has no attribute `bar`"
## Test Plan
Mdtests and snapshots updated
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
This PR implements semantic syntax error where alternative patterns bind
different names
## Test Plan
<!-- How was it tested? -->
I have written inline tests as directed in #17412
---------
Signed-off-by: 11happy <soni5happy@gmail.com>
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
## Summary
Derived from #20900
Implement `VarianceInferable` for `KnownInstanceType` (especially for
`KnownInstanceType::TypeAliasType`).
The variance of a type alias matches its value type. In normal usage,
type aliases are expanded to value types, so the variance of a type
alias can be obtained without implementing this. However, for example,
if we want to display the variance when hovering over a type alias, we
need to be able to obtain the variance of the type alias itself (cf.
#20900).
## Test Plan
I couldn't come up with a way to test this in mdtest, so I'm testing it
in a test submodule at the end of `types.rs`.
I also added a test to `mdtest/generics/pep695/variance.md`, but it
passes without the changes in this PR.
## Summary
Fixes#20774 by tracking whether an `InterpolatedStringState` element is
nested inside of another interpolated element. This feels like kind of a
naive fix, so I'm welcome to other ideas. But it resolves the problem in
the issue and clears up the syntax error in the black compatibility
test, without affecting many other cases.
The other affected case is actually interesting too because the
[input](96b156303b/crates/ruff_python_formatter/resources/test/fixtures/ruff/expression/fstring.py (L707))
is invalid, but the previous quote selection fixed the invalid syntax:
```pycon
Python 3.11.13 (main, Sep 2 2025, 14:20:25) [Clang 20.1.4 ] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> f'{1: abcd "{'aa'}" }' # input
File "<stdin>", line 1
f'{1: abcd "{'aa'}" }'
^^
SyntaxError: f-string: expecting '}'
>>> f'{1: abcd "{"aa"}" }' # old output
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: Invalid format specifier ' abcd "aa" ' for object of type 'int'
>>> f'{1: abcd "{'aa'}" }' # new output
File "<stdin>", line 1
f'{1: abcd "{'aa'}" }'
^^
SyntaxError: f-string: expecting '}'
```
We now preserve the invalid syntax in the input.
Unfortunately, this also seems to be another edge case I didn't consider
in https://github.com/astral-sh/ruff/pull/20867 because we don't flag
this as a syntax error after 0.14.1:
<details><summary>Shell output</summary>
<p>
```
> uvx ruff@0.14.0 check --ignore ALL --target-version py311 - <<EOF
f'{1: abcd "{'aa'}" }'
EOF
invalid-syntax: Cannot reuse outer quote character in f-strings on Python 3.11 (syntax was added in Python 3.12)
--> -:1:14
|
1 | f'{1: abcd "{'aa'}" }'
| ^
|
Found 1 error.
> uvx ruff@0.14.1 check --ignore ALL --target-version py311 - <<EOF
f'{1: abcd "{'aa'}" }'
EOF
All checks passed!
> uvx python@3.11 -m ast <<EOF
f'{1: abcd "{'aa'}" }'
EOF
Traceback (most recent call last):
File "<frozen runpy>", line 198, in _run_module_as_main
File "<frozen runpy>", line 88, in _run_code
File "/home/brent/.local/share/uv/python/cpython-3.11.13-linux-x86_64-gnu/lib/python3.11/ast.py", line 1752, in <module>
main()
File "/home/brent/.local/share/uv/python/cpython-3.11.13-linux-x86_64-gnu/lib/python3.11/ast.py", line 1748, in main
tree = parse(source, args.infile.name, args.mode, type_comments=args.no_type_comments)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/brent/.local/share/uv/python/cpython-3.11.13-linux-x86_64-gnu/lib/python3.11/ast.py", line 50, in parse
return compile(source, filename, mode, flags,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<stdin>", line 1
f'{1: abcd "{'aa'}" }'
^^
SyntaxError: f-string: expecting '}'
```
</p>
</details>
I assumed that was the same `ParseError` as the one caused by
`f"{1:""}"`, but this is a nested interpolation inside of the format
spec.
## Test Plan
New test copied from the black compatibility test. I guess this is a
duplicate now, I started working on this branch before the new black
tests were imported, so I could delete the separate test in our fixtures
if that's preferable.
## Summary
Support `dataclass_transform` when used on a (base) class.
## Typing conformance
* The changes in `dataclasses_transform_class.py` look good, just a few
mistakes due to missing `alias` support.
* I didn't look closely at the changes in
`dataclasses_transform_converter.py` since we don't support `converter`
yet.
## Ecosystem impact
The impact looks huge, but it's concentrated on a single project (ibis).
Their setup looks more or less like this:
* the real `Annotatable`:
d7083c2c96/ibis/common/grounds.py (L100-L101)
* the real `DataType`:
d7083c2c96/ibis/expr/datatypes/core.py (L161-L179)
* the real `Array`:
d7083c2c96/ibis/expr/datatypes/core.py (L1003-L1006)
```py
from typing import dataclass_transform
@dataclass_transform()
class Annotatable:
pass
class DataType(Annotatable):
nullable: bool = True
class Array[T](DataType):
value_type: T
```
They expect something like `Array([1, 2])` to work, but ty, pyright,
mypy, and pyrefly would all expect there to be a first argument for the
`nullable` field on `DataType`. I don't really understand on what
grounds they expect the `nullable` field to be excluded from the
signature, but this seems to be the main reason for the new diagnostics
here. Not sure if related, but it looks like their typing setup is not
really complete
(https://github.com/ibis-project/ibis/issues/6844#issuecomment-1868274770,
this thread also mentions `dataclass_transform`).
## Test Plan
Update pre-existing tests.
Detect legacy namespace packages and treat them like namespace packages
when looking them up as the *parent* of the module we're interested in.
In all other cases treat them like a regular package.
(This PR is coauthored by @MichaReiser in a shared coding session)
Fixes https://github.com/astral-sh/ty/issues/838
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
Prefer the declared type for collection literals, e.g.,
```py
x: list[Any] = [1, "2", (3,)]
reveal_type(x) # list[Any]
```
This solves a large part of https://github.com/astral-sh/ty/issues/136
for invariant generics, where respecting the declared type is a lot more
important. It also means that annotated dict literals with `dict[_,
Any]` is a way out of https://github.com/astral-sh/ty/issues/1248.
We have to track whether a typevar appears in a position where it's
inferable or not. In a non-inferable position (in the body of the
generic class or function that binds it), assignability must hold for
every possible specialization of the typevar. In an inferable position,
it only needs to hold for _some_ specialization.
https://github.com/astral-sh/ruff/pull/20093 is working on using
constraint sets to model assignability of typevars, and the constraint
sets that we produce will be the same for inferable vs non-inferable
typevars; what changes is what we _compare_ that constraint set to. (For
a non-inferable typevar, the constraint set must equal the set of valid
specializations; for an inferable typevar, it must not be `never`.)
When I first added support for tracking inferable vs non-inferable
typevars, it seemed like it would be easiest to have separate `Type`
variants for each. The alternative (which lines up with the Δ set in
[POPL15](https://doi.org/10.1145/2676726.2676991)) would be to
explicitly plumb through a list of inferable typevars through our type
property methods. That seemed cumbersome.
In retrospect, that was the wrong decision. We've had to jump through
hoops to translate types between the inferable and non-inferable
variants, which has been quite brittle. Combined with the original point
above, that much of the assignability logic will become more identical
between inferable and non-inferable, there is less justification for the
two `Type` variants. And plumbing an extra `inferable` parameter through
all of these methods turns out to not be as bad as I anticipated.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
Use the declared type of variables as type context for the RHS of assignment expressions, e.g.,
```py
x: list[int | str]
x = [1]
reveal_type(x) # revealed: list[int | str]
```
## Summary
Ignore the type context when specializing a generic call if it leads to
an unnecessarily wide return type. For example, [the example mentioned
here](https://github.com/astral-sh/ruff/pull/20796#issuecomment-3403319536)
works as expected after this change:
```py
def id[T](x: T) -> T:
return x
def _(i: int):
x: int | None = id(i)
y: int | None = i
reveal_type(x) # revealed: int
reveal_type(y) # revealed: int
```
I also added extended our usage of `filter_disjoint_elements` to tuple
and typed-dict inference, which resolves
https://github.com/astral-sh/ty/issues/1266.
## Summary
Add support for the `field_specifiers` parameter on
`dataclass_transform` decorator calls.
closes https://github.com/astral-sh/ty/issues/1068
## Conformance test results
All true positives ✔️
## Ecosystem analysis
* `trio`: this is the kind of change that I would expect from this PR.
The code makes use of a dataclass `Outcome` with a `_unwrapped: bool =
attr.ib(default=False, eq=False, init=False)` field that is excluded
from the `__init__` signature, so we now see a bunch of
constructor-call-related errors going away.
* `home-assistant/core`: They have a `domain: str = attr.ib(init=False,
repr=False)` field and then use
```py
@domain.default
def _domain_default(self) -> str:
# …
```
This accesses the `default` attribute on `dataclasses.Field[…]` with a
type of `default: _T | Literal[_MISSING_TYPE.MISSING]`, so we get those
"Object of type `_MISSING_TYPE` is not callable" errors. I don't really
understand how that is supposed to work. Even if `_MISSING_TYPE` would
be absent from that union, what does this try to call? pyright also
issues an error and it doesn't seem to work at runtime? So this looks
like a true positive?
* `attrs`: Similar here. There are some new diagnostics on code that
tries to access `.validator` on a field. This *does* work at runtime,
but I'm not sure how that is supposed to type-check (without a [custom
plugin](2c6c395935/mypy/plugins/attrs.py (L575-L602))).
pyright errors on this as well.
* A handful of new false positives because we don't support `alias` yet
## Test Plan
Updated tests.
Summary
--
This PR unifies the two different ways Ruff and ty construct syntax
errors. Ruff has been storing the primary message in the diagnostic
itself, while ty attached the message to the primary annotation:
```
> ruff check try.py
invalid-syntax: name capture `x` makes remaining patterns unreachable
--> try.py:2:10
|
1 | match 42:
2 | case x: ...
| ^
3 | case y: ...
|
Found 1 error.
> uvx ty check try.py
WARN ty is pre-release software and not ready for production use. Expect to encounter bugs, missing features, and fatal errors.
Checking ------------------------------------------------------------ 1/1 files
error[invalid-syntax]
--> try.py:2:10
|
1 | match 42:
2 | case x: ...
| ^ name capture `x` makes remaining patterns unreachable
3 | case y: ...
|
Found 1 diagnostic
```
I think there are benefits to both approaches, and I do like ty's
version, but I feel like we should pick one (and it might help with
#20901 eventually). I slightly prefer Ruff's version, so I went with
that. Hopefully this isn't too controversial, but I'm happy to close
this if it is.
Note that this shouldn't change any other diagnostic formats in ty
because
[`Diagnostic::primary_message`](98d27c4128/crates/ruff_db/src/diagnostic/mod.rs (L177))
was already falling back to the primary annotation message if the
diagnostic message was empty. As a result, I think this change will
partially resolve the FIXME therein.
Test Plan
--
Existing tests with updated snapshots
## Summary
Implement `docstring-extraneous-parameter` (`DOC102`). This rule checks
that all parameters present in a functions docstring are also present in
its signature.
Split from #13280, per this
[comment](https://github.com/astral-sh/ruff/pull/13280#issuecomment-3280575506).
Part of #12434.
## Test Plan
Test cases added.
---------
Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
This is the ultra-minimal implementation of
* https://github.com/astral-sh/ty/issues/296
that was previously discussed as a good starting point. In particular we
don't actually bother trying to figure out the exact python versions,
but we still mention "hey btw for No Reason At All... you're on python
3.10" when you try to access something that has a definition rooted in
the stdlib that we believe exists sometimes.
This is a drive-by improvement that I stumbled backwards into while
looking into
* https://github.com/astral-sh/ty/issues/296
I was writing some simple tests for "thing not in old version of stdlib"
diagnostics and checked what was added in 3.14, and saw
`compression.zstd` and to my surprise discovered that `import
compression.zstd` and `from compression import zstd` had completely
different quality diagnostics.
This is because `compression` and `compression.zstd` were *both*
introduced in 3.14, and so per VERSIONS policy only an entry for
`compression` was added, and so we don't actually have any definite info
on `compression.zstd` and give up on producing a diagnostic. However the
`from compression import zstd` form fails on looking up `compression`
and we *do* have an exact match for that, so it gets a better
diagnostic!
(aside: I have now learned about the VERSIONS format and I *really* wish
they would just enumerate all the submodules but, oh well!)
The fix is, when handling an import failure, if we fail to find an exact
match *we requery with the parent module*. In cases like
`compression.zstd` this lets us at least identify that, hey, not even
`compression` exists, and luckily that fixes the whole issue. In cases
where the parent module and submodule were introduced at different times
then we may discover that the parent module is in-range and that's fine,
we don't produce the richer stdlib diagnostic.
## Summary
`dataclasses.field` and field-specifier functions of commonly used
libraries like `pydantic`, `attrs`, and `SQLAlchemy` all return the
default type for the field (or `Any`) instead of an actual `Field`
instance, even if this is not what happens at runtime. Let's make use of
this fact and assume that *all* field specifiers return the type of the
default value of the field.
For standard dataclasses, this leads to more or less the same outcome
(see test diff for details), but this change is important for 3rd party
dataclass-transformers.
## Test Plan
Tested the consequences of this change on the field-specifiers branch as
well.
Takayuki Maeda
renovate[bot]
Micha Reiser
Douglas Creager
Bhuminjay Soni
Brent Westbrook
Dylan
Alex Waygood
Dan Parizher
Shahar Naveh
Auguste Lalande
Ibraheem Ahmed
wangxiaolei
Wei Lee
Shunsuke Shibayama
decorator-factory
Eric Mark Martin
David Peter
Aria Desires
Hengky Kurniawan
Robsdedude
Loïc Riegel
Renkai Ge
Mark Z. Ding
Carl Meyer