In #17403 I added a comment asserting that all same-kind literal types
share all the same super-types. This is true, with two notable
exceptions: the types `AlwaysTruthy` and `AlwaysFalsy`. These two types
are super-types of some literal types within a given kind and not
others: `Literal[0]`, `Literal[""]`, and `Literal[b""]` inhabit
`AlwaysFalsy`, while other literals inhabit `AlwaysTruthy`.
This PR updates the literal-unions optimization to handle these types
correctly.
Fixes https://github.com/astral-sh/ruff/issues/17447
Verified locally that `QUICKCHECK_TESTS=100000 cargo test -p
red_knot_python_semantic -- --ignored types::property_tests::stable` now
passes again.
## Summary
Fixes#17147.
This was landed in #17149 and then reverted in #17335 because it caused
cycle panics in checking pybind11. #17456 fixed the cause of that panic.
## Test Plan
Add new narrow/assert.md test file
Co-authored-by: Matthew Mckee <matthewmckee04@yahoo.co.uk>
## Summary
We were over-conflating the conditions for deferred name resolution.
`from __future__ import annotations` defers annotations, but not class
bases. In stub files, class bases are also deferred. Modeling this
correctly also reduces likelihood of cycles in Python files using `from
__future__ import annotations` (since deferred resolution is inherently
cycle-prone). The same cycles are still possible in `.pyi` files, but
much less likely, since typically there isn't anything in a `pyi` file
that would cause an early return from a scope, or otherwise cause
visibility constraints to persist to end of scope. Usually there is only
code at module global scope and class scope, which can't have `return`
statements, and `raise` or `assert` statements in a stub file would be
very strange. (Technically according to the spec we'd be within our
rights to just forbid a whole bunch of syntax outright in a stub file,
but I kinda like minimizing unnecessary differences between the handling
of Python files and stub files.)
## Test Plan
Added mdtests.
## Summary
Part of #15383, this PR adds support for overloaded callables.
Typing spec: https://typing.python.org/en/latest/spec/overload.html
Specifically, it does the following:
1. Update the `FunctionType::signature` method to return signatures from
a possibly overloaded callable using a new `FunctionSignature` enum
2. Update `CallableType` to accommodate overloaded callable by updating
the inner type to `Box<[Signature]>`
3. Update the relation methods on `CallableType` with logic specific to
overloads
4. Update the display of callable type to display a list of signatures
enclosed by parenthesis
5. Update `CallableTypeOf` special form to recognize overloaded callable
6. Update subtyping, assignability and fully static check to account for
callables (equivalence is planned to be done as a follow-up)
For (2), it is required to be done in this PR because otherwise I'd need
to add some workaround for `into_callable_type` and I though it would be
best to include it in here.
For (2), another possible design would be convert `CallableType` in an
enum with two variants `CallableType::Single` and
`CallableType::Overload` but I decided to go with `Box<[Signature]>` for
now to (a) mirror it to be equivalent to `overload` field on
`CallableSignature` and (b) to avoid any refactor in this PR. This could
be done in a follow-up to better split the two kind of callables.
### Design
There were two main candidates on how to represent the overloaded
definition:
1. To include it in the existing infrastructure which is what this PR is
doing by recognizing all the signatures within the
`FunctionType::signature` method
2. To create a new `Overload` type variant
<details><summary>For context, this is what I had in mind with the new
type variant:</summary>
<p>
```rs
pub enum Type {
FunctionLiteral(FunctionType),
Overload(OverloadType),
BoundMethod(BoundMethodType),
...
}
pub struct OverloadType {
// FunctionLiteral or BoundMethod
overloads: Box<[Type]>,
// FunctionLiteral or BoundMethod
implementation: Option<Type>
}
pub struct BoundMethodType {
kind: BoundMethodKind,
self_instance: Type,
}
pub enum BoundMethodKind {
Function(FunctionType),
Overload(OverloadType),
}
```
</p>
</details>
The main reasons to choose (1) are the simplicity in the implementation,
reusing the existing infrastructure, avoiding any complications that the
new type variant has specifically around the different variants between
function and methods which would require the overload type to use `Type`
instead.
### Implementation
The core logic is how to collect all the overloaded functions. The way
this is done in this PR is by recording a **use** on the `Identifier`
node that represents the function name in the use-def map. This is then
used to fetch the previous symbol using the same name. This way the
signatures are going to be propagated from top to bottom (from first
overload to the final overload or the implementation) with each function
/ method. For example:
```py
from typing import overload
@overload
def foo(x: int) -> int: ...
@overload
def foo(x: str) -> str: ...
def foo(x: int | str) -> int | str:
return x
```
Here, each definition of `foo` knows about all the signatures that comes
before itself. So, the first overload would only see itself, the second
would see the first and itself and so on until the implementation or the
final overload.
This approach required some updates specifically recognizing
`Identifier` node to record the function use because it doesn't use
`ExprName`.
## Test Plan
Update existing test cases which were limited by the overload support
and add test cases for the following cases:
* Valid overloads as functions, methods, generics, version specific
* Invalid overloads as stated in
https://typing.python.org/en/latest/spec/overload.html#invalid-overload-definitions
(implementation will be done in a follow-up)
* Various relation: fully static, subtyping, and assignability (others
in a follow-up)
## Ecosystem changes
_WIP_
After going through the ecosystem changes (there are a lot!), here's
what I've found:
We need assignability check between a callable type and a class literal
because a lot of builtins are defined as classes in typeshed whose
constructor method is overloaded e.g., `map`, `sorted`, `list.sort`,
`max`, `min` with the `key` parameter, `collections.abc.defaultdict`,
etc. (https://github.com/astral-sh/ruff/issues/17343). This makes up
most of the ecosystem diff **roughly 70 diagnostics**. For example:
```py
from collections import defaultdict
# red-knot: No overload of bound method `__init__` matches arguments [lint:no-matching-overload]
defaultdict(int)
# red-knot: No overload of bound method `__init__` matches arguments [lint:no-matching-overload]
defaultdict(list)
class Foo:
def __init__(self, x: int):
self.x = x
# red-knot: No overload of function `__new__` matches arguments [lint:no-matching-overload]
map(Foo, ["a", "b", "c"])
```
Duplicate diagnostics in unpacking
(https://github.com/astral-sh/ruff/issues/16514) has **~16
diagnostics**.
Support for the `callable` builtin which requires `TypeIs` support. This
is **5 diagnostics**. For example:
```py
from typing import Any
def _(x: Any | None) -> None:
if callable(x):
# red-knot: `Any | None`
# Pyright: `(...) -> object`
# mypy: `Any`
# pyrefly: `(...) -> object`
reveal_type(x)
```
Narrowing on `assert` which has **11 diagnostics**. This is being worked
on in https://github.com/astral-sh/ruff/pull/17345. For example:
```py
import re
match = re.search("", "")
assert match
match.group() # error: [possibly-unbound-attribute]
```
Others:
* `Self`: 2
* Type aliases: 6
* Generics: 3
* Protocols: 13
* Unpacking in comprehension: 1
(https://github.com/astral-sh/ruff/pull/17396)
## Performance
Refer to
https://github.com/astral-sh/ruff/pull/17366#issuecomment-2814053046.
## Summary
Add more narrowing analysis for match statements:
* add narrowing constraints from guard expressions
* add negated constraints from previous predicates and guards to
subsequent cases
This PR doesn't address that guards can mutate your subject, and so
theoretically invalidate some of these narrowing constraints that you've
previously accumulated. Some prior art on this issue [here][mutable
guards].
[mutable guards]:
https://www.irif.fr/~scherer/research/mutable-patterns/mutable-patterns-mlworkshop2024-abstract.pdf
## Test Plan
Add some new tests, and update some existing ones
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
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## Summary
Fixes#14866Fixes#17437
## Test Plan
Update mdtests in `narrow/`
## Summary
This PR extends version-related syntax error detection to red-knot. The
main changes here are:
1. Passing `ParseOptions` specifying a `PythonVersion` to parser calls
2. Adding a `python_version` method to the `Db` trait to make this
possible
3. Converting `UnsupportedSyntaxError`s to `Diagnostic`s
4. Updating existing mdtests to avoid unrelated syntax errors
My initial draft of (1) and (2) in #16090 instead tried passing a
`PythonVersion` down to every parser call, but @MichaReiser suggested
the `Db` approach instead
[here](https://github.com/astral-sh/ruff/pull/16090#discussion_r1969198407),
and I think it turned out much nicer.
All of the new `python_version` methods look like this:
```rust
fn python_version(&self) -> ruff_python_ast::PythonVersion {
Program::get(self).python_version(self)
}
```
with the exception of the `TestDb` in `ruff_db`, which hard-codes
`PythonVersion::latest()`.
## Test Plan
Existing mdtests, plus a new mdtest to see at least one of the new
diagnostics.
## Summary
This changeset allows us to generate the signature of synthesized
`__init__` functions in dataclasses by analyzing the fields on the class
(and its superclasses). There are certain things that I have not yet
attempted to model in this PR, like `kw_only`,
[`dataclasses.KW_ONLY`](https://docs.python.org/3/library/dataclasses.html#dataclasses.KW_ONLY)
or functionality around
[`dataclasses.field`](https://docs.python.org/3/library/dataclasses.html#dataclasses.field).
ticket: https://github.com/astral-sh/ruff/issues/16651
## Ecosystem analysis
These two seem to depend on missing features in generics (see [relevant
code
here](9898ccbb78/tests/core/test_generics.py (L54))):
> ```diff
> + error[lint:unknown-argument]
/tmp/mypy_primer/projects/dacite/tests/core/test_generics.py:54:24:
Argument `x` does not match any known parameter
> + error[lint:unknown-argument]
/tmp/mypy_primer/projects/dacite/tests/core/test_generics.py:54:38:
Argument `y` does not match any known parameter
> ```
These two are true positives. See [relevant code
here](9898ccbb78/tests/core/test_config.py (L154-L161)).
> ```diff
> + error[lint:invalid-argument-type]
/tmp/mypy_primer/projects/dacite/tests/core/test_config.py:161:24:
Argument to this function is incorrect: Expected `int`, found
`Literal["test"]`
> + error[lint:invalid-argument-type]
/tmp/mypy_primer/projects/dacite/tests/core/test_config.py:172:24:
Argument to this function is incorrect: Expected `int | float`, found
`Literal["test"]`
> ```
This one depends on `**` unpacking of dictionaries, which we don't
support yet:
> ```diff
> + error[lint:missing-argument]
/tmp/mypy_primer/projects/mypy_primer/mypy_primer/globals.py:218:11: No
arguments provided for required parameters `new`, `old`, `repo`,
`type_checker`, `mypyc_compile_level`, `custom_typeshed_repo`,
`new_typeshed`, `old_typeshed`, `new_prepend_path`, `old_prepend_path`,
`additional_flags`, `project_selector`, `known_dependency_selector`,
`local_project`, `expected_success`, `project_date`, `shard_index`,
`num_shards`, `output`, `old_success`, `coverage`, `bisect`,
`bisect_output`, `validate_expected_success`,
`measure_project_runtimes`, `concurrency`, `base_dir`, `debug`, `clear`
> ```
## Test Plan
New Markdown tests.
## Summary
Support dataclasses with `order=True`:
```py
@dataclass(order=True)
class WithOrder:
x: int
WithOrder(1) < WithOrder(2) # no error
```
Also adds some additional tests to `dataclasses.md`.
ticket: #16651
## Test Plan
New Markdown tests
This PR adds **_very_** basic inference of generic typevars at call
sites. It does not bring in a full unification algorithm, and there are
a few TODOs in the test suite that are not discharged by this. But it
handles a good number of useful cases! And the PR does not add anything
that would go away with a more sophisticated constraint solver.
In short, we just look for typevars in the formal parameters, and assume
that the inferred type of the corresponding argument is what that
typevar should map to. If a typevar appears more than once, we union
together the corresponding argument types.
Cases we are not yet handling:
- We are not widening literals.
- We are not recursing into parameters that are themselves generic
aliases.
- We are not being very clever with parameters that are union types.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
This is similar to https://github.com/astral-sh/ruff/pull/17095, it adds
assignability check for bound methods to callables.
## Test Plan
Add test cases to for assignability; specifically it uses gradual types
because otherwise it would just delegate to `is_subtype_of`.
## Summary
closes#16615
This PR includes:
- Introduces a new type: `Type::BoundSuper`
- Implements member lookup for `Type::BoundSuper`, resolving attributes
by traversing the MRO starting from the specified class
- Adds support for inferring appropriate arguments (`pivot_class` and
`owner`) for `super()` when it is used without arguments
When `super(..)` appears in code, it can be inferred into one of the
following:
- `Type::Unknown`: when a runtime error would occur (e.g. calling
`super()` out of method scope, or when parameter validation inside
`super` fails)
- `KnownClass::Super::to_instance()`: when the result is an *unbound
super object* or when a dynamic type is used as parameters (MRO
traversing is meaningless)
- `Type::BoundSuper`: the common case, representing a properly
constructed `super` instance that is ready for MRO traversal and
attribute resolution
### Terminology
Python defines the terms *bound super object* and *unbound super
object*.
An **unbound super object** is created when `super` is called with only
one argument (e.g.
`super(A)`). This object may later be bound via the `super.__get__`
method. However, this form is rarely used in practice.
A **bound super object** is created either by calling
`super(pivot_class, owner)` or by using the implicit form `super()`,
where both arguments are inferred from the context. This is the most
common usage.
### Follow-ups
- Add diagnostics for `super()` calls that would result in runtime
errors (marked as TODO)
- Add property tests for `Type::BoundSuper`
## Test Plan
- Added `mdtest/class/super.md`
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
Until we optimize our full union/intersection representation to
efficiently handle large numbers of same-kind literal types "as a
block", set a fairly low limit on the size of unions of literals.
We will want to increase this limit once we've made the broader
efficiency improvement (tracked in
https://github.com/astral-sh/ruff/issues/17420).
## Test Plan
`cargo bench --bench red_knot`
## Summary
Special-case literal types in `UnionBuilder` to speed up building large
unions of literals.
This optimization is extremely effective at speeding up building even a
very large union (it improves the large-unions benchmark by 41x!). The
problem we can run into is that it is easy to then run into another
operation on the very large union (for instance, narrowing may add it to
an intersection, which then distributes it over the intersection) which
is still slow.
I think it is possible to avoid this by extending this optimized
"grouped" representation throughout not just `UnionBuilder`, but all of
our union and intersection representations. I have some work in this
direction, but rather than spending more time on it right now, I'd
rather just land this much, along with a limit on the size of these
unions (to avoid building really big unions quickly and then hitting
issues where they are used.)
## Test Plan
Existing tests and benchmarks.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
Fixes incorrect negated type eq and ne assertions in
infer_binary_intersection_type_comparison
fixes#17360
## Test Plan
Remove and update some now incorrect tests
This reworks the assignability/subtyping relations a bit to handle
typevars better:
1. For the most part, types are not assignable to typevars, since
there's no guarantee what type the typevar will be specialized to.
2. An intersection is an exception, if it contains the typevar itself as
one of the positive elements. This should fall out from the other
clauses automatically, since a typevar is assignable to itself, and an
intersection is assignable to something if any positive element is
assignable to that something.
3. Constrained typevars are an exception, since they must be specialized
to _exactly_ one of the constraints, not to a _subtype_ of a constraint.
If a type is assignable to every constraint, then the type is also
assignable to the constrained typevar.
We already had a special case for (3), but the ordering of it relative
to the intersection clauses meant we weren't catching (2) correctly. To
fix this, we keep the special case for (3), but fall through to the
other match arms for non-constrained typevars and if the special case
isn't true for a constrained typevar.
Closes https://github.com/astral-sh/ruff/issues/17364
## Summary
Add very early support for dataclasses. This is mostly to make sure that
we do not emit false positives on dataclass construction, but it also
lies some foundations for future extensions.
This seems like a good initial step to merge to me, as it basically
removes all false positives on dataclass constructor calls. This allows
us to use the ecosystem checks for making sure we don't introduce new
false positives as we continue to work on dataclasses.
## Ecosystem analysis
I re-ran the mypy_primer evaluation of [the `__init__`
PR](https://github.com/astral-sh/ruff/pull/16512) locally with our
current mypy_primer version and project selection. It introduced 1597
new diagnostics. Filtering those by searching for `__init__` and
rejecting those that contain `invalid-argument-type` (those could not
possibly be solved by this PR) leaves 1281 diagnostics. The current
version of this PR removes 1171 diagnostics, which leaves 110
unaccounted for. I extracted the lint + file path for all of these
diagnostics and generated a diff (of diffs), to see which
`__init__`-diagnostics remain. I looked at a subset of these: There are
a lot of `SomeClass(*args)` calls where we don't understand the
unpacking yet (this is not even related to `__init__`). Some others are
related to `NamedTuple`, which we also don't support yet. And then there
are some errors related to `@attrs.define`-decorated classes, which
would probably require support for `dataclass_transform`, which I made
no attempt to include in this PR.
## Test Plan
New Markdown tests.
## Summary
* Partial #17238
* Flyby from discord discussion - `todo_type!` now statically checks for
no parens in the message to avoid issues between debug & release build
tests
## Test Plan
many mdtests are changing
## Summary
Infer precise Boolean literal types for `str.startswith` calls where the
instance and the prefix are both string literals. This allows us to
understand `sys.platform.startswith(…)` branches.
## Test Plan
New Markdown tests
## Summary
For silencing `invalid-type-form` diagnostics in unreachable code, we
use the same approach that we use before and check the reachability that
we already record.
For silencing `invalid-bases`, we simply check if the type of the base
is `Never`. If so, we silence the diagnostic with the argument that the
class construction would never happen.
## Test Plan
Updated Markdown tests.
## Summary
Similar to what we did for `unresolved-reference` and
`unresolved-attribute`, we now also silence `unresolved-import`
diagnostics if the corresponding `import` statement is unreachable.
This addresses the (already closed) issue #17049.
## Test Plan
Adapted Markdown tests.
This finally completes the deletion of all old diagnostic types.
We do this by migrating the second (and last) use of secondary
diagnostic messages: to highlight the return type of a function
definition when its return value is inconsistent with the type.
Like the last diagnostic, we do actually change the message here a bit.
We don't need a sub-diagnostic here, and we can instead just add a
secondary annotation to highlight the return type.
This is the first use of the new `lint()` reporter.
I somewhat skipped a step here and also modified the actual diagnostic
message itself. The snapshots should tell the story.
We couldn't do this before because we had no way of differentiating
between "message for the diagnostic as a whole" and "message for a
specific code annotation." Now we can, so we can write more precise
messages based on the assumption that users are also seeing the code
snippet.
The downside here is that the actual message text can become quite vague
in the absence of the code snippet. This occurs, for example, with
concise diagnostic formatting. It's unclear if we should do anything
about it. I don't really see a way to make it better that doesn't
involve creating diagnostics with messages for each mode, which I think
would be a major PITA.
The upside is that this code gets a bit simpler, and we very
specifically avoid doing extra work if this specific lint is disabled.
This required a bit of surgery in the diagnostic matching and more
faffing about using a "concise" message from a diagnostic instead of
only printing the "primary" message.
## Summary
Basically just repeat the same thing that we did for
`unresolved-reference`, but now for attribute expressions.
We now also handle the case where the unresolved attribute (or the
unresolved reference) diagnostic originates from a stringified type
annotation.
And I made the evaluation of reachability constraints lazy (will only be
evaluated right before we are about to emit a diagnostic).
## Test Plan
New Markdown tests for stringified annotations.
I merged #17149 without checking the ecosystem results, and it still
caused a cycle panic in pybind11. Reverting for now until I fix that, so
we don't lose the ecosystem signal on other PRs.
## Summary
Track the reachability of nested scopes within their parent scopes. We
use this as an additional requirement for emitting
`unresolved-reference` diagnostics (and in the future,
`unresolved-attribute` and `unresolved-import`). This means that we only
emit `unresolved-reference` for a given use of a symbol if the use
itself is reachable (within its own scope), *and if the scope itself is
reachable*. For example, no diagnostic should be emitted for the use of
`x` here:
```py
if False:
x = 1
def f():
print(x) # this use of `x` is reachable inside the `f` scope,
# but the whole `f` scope is not reachable.
```
There are probably more fine-grained ways of solving this problem, but
they require a more sophisticated understanding of nested scopes (see
#15777, in particular
https://github.com/astral-sh/ruff/issues/15777#issuecomment-2788950267).
But it doesn't seem completely unreasonable to silence *this specific
kind of error* in unreachable scopes.
## Test Plan
Observed changes in reachability tests and ecosystem.
## Summary
Update Salsa to pull in https://github.com/salsa-rs/salsa/pull/788 which
fixes the, by now, famous *access to field whilst the value is being
initialized*.
This PR also re-enables all tests that previously triggered the panic.
## Test Plan
`cargo test`
## Summary
There is a new official URL for the typing documentation:
https://typing.python.org/
Change all https://typing.readthedocs.io/ links to use the new sub
domain, which is slightly shorter and looks more official.
## Test Plan
Tested to see if each and every new URL is accessible. I noticed that
some links go to https://typing.python.org/en/latest/source/stubs.html
which seems to be outdated, but that is a separate issue. The same page
shows up for the old URL.
This PR lets you explicitly specialize a generic class using a subscript
expression. It introduces three new Rust types for representing classes:
- `NonGenericClass`
- `GenericClass` (not specialized)
- `GenericAlias` (specialized)
and two enum wrappers:
- `ClassType` (a non-generic class or generic alias, represents a class
_type_ at runtime)
- `ClassLiteralType` (a non-generic class or generic class, represents a
class body in the AST)
We also add internal support for specializing callables, in particular
function literals. (That is, the internal `Type` representation now
attaches an optional specialization to a function literal.) This is used
in this PR for the methods of a generic class, but should also give us
most of what we need for specializing generic _functions_ (which this PR
does not yet tackle).
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
As discussed in https://github.com/astral-sh/ruff/issues/16983 and
"mitigate" said issue for the alpha.
This PR changes the default for `PythonPlatform` to be the current
platform rather than `all`.
I'm not sure if we should be as sophisticated as supporting `ios` and
`android` as defaults but it was easy...
## Test Plan
Updated Markdown tests.
---------
Co-authored-by: David Peter <mail@david-peter.de>
## Summary
This is a new test case that I don't know how to handle yet. It leads to
many false positives in `rich/tests/test_win32_console.py`, which does
something like:
```py
if sys.platform == "win32":
from windows_only_module import some_symbol
some_other_symbol = 1
def some_test_case():
use(some_symbol) # Red Knot: unresolved-reference
use(some_other_symbol) # Red Knot: unresolved-reference
```
Also adds a test for using unreachable symbols in type annotations or as
class bases.
## Summary
* Addresses #16511 for simple cases where only `__init__` method is
bound on class or doesn't exist at all.
* fixes a bug with argument counting in bound method diagnostics
Caveats:
* No handling of `__new__` or modified `__call__` on metaclass.
* This leads to a couple of false positive errors in tests
## Test Plan
- A couple new cases in mdtests
- cargo nextest run -p red_knot_python_semantic --no-fail-fast
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Co-authored-by: David Peter <sharkdp@users.noreply.github.com>
## Summary
We already have partial "support" for `assert_never`, because it is
annotated as
```pyi
def assert_never(arg: Never, /) -> Never: ...
```
in typeshed. So we already emit a `invalid-argument-type` diagnostic if
the argument type to `assert_never` is not assignable to `Never`.
That is not enough, however. Gradual types like `Any`, `Unknown`,
`@Todo(…)` or `Any & int` can be assignable to `Never`. Which means that
we didn't issue any diagnostic in those cases.
Also, it seems like `assert_never` deserves a dedicated diagnostic
message, not just a generic "invalid argument type" error.
## Test Plan
New Markdown tests.
## Summary
This implements a new approach to silencing `unresolved-reference`
diagnostics by keeping track of the reachability of each use of a
symbol. The changes merged in
https://github.com/astral-sh/ruff/pull/17169 are still needed for the
"Use of variable in nested function" test case, but that could also be
solved in another way eventually (see
https://github.com/astral-sh/ruff/issues/15777). We can use the same
technique to silence `unresolved-import` and `unresolved-attribute`
false-positives, but I think this could be merged in isolation.
## Test Plan
New Markdown tests, ecosystem tests
## Summary
This PR adds support for stub packages, except for partial stub packages
(a stub package is always considered non-partial).
I read the specification at
[typing.python.org/en/latest/spec/distributing.html#stub-only-packages](https://typing.python.org/en/latest/spec/distributing.html#stub-only-packages)
but I found it lacking some details, especially on how to handle
namespace packages or when the regular and stub packages disagree on
whether they're namespace packages. I tried to document my decisions in
the mdtests where the specification isn't clear and compared the
behavior to Pyright.
Mypy seems to only support stub packages in the venv folder. At least,
it never picked up my stub packages otherwise. I decided not to spend
too much time fighting mypyp, which is why I focused the comparison
around Pyright
Closes https://github.com/astral-sh/ruff/issues/16612
## Test plan
Added mdtests
## Summary
Some more edge cases that I thought of while working on integrating
knowledge of statically known branches into the `*`-import machinery
## Test Plan
`cargo test -p red_knot_python_semantic`
## Summary
This PR does the following things:
- Fixes the `python` configuration setting for mdtest (added in
https://github.com/astral-sh/ruff/pull/17221) so that it expects a path
pointing to a venv's `sys.prefix` variable rather than the a path
pointing to the venv's `site-packages` subdirectory. This brings the
`python` setting in mdtest in sync with our CLI `--python` flag.
- Tweaks mdtest so that it automatically creates a valid `pyvenv.cfg`
file for you if you don't specify one. This makes it much more ergonomic
to write an mdtest with a custom `python` setting: red-knot will reject
a `python` setting that points to a directory that doesn't have a
`pyvenv.cfg` file in it
- Tweaks mdtest so that it doesn't check a custom `pyvenv.cfg` as Python
source code if you _do_ add a custom `pyvenv.cfg` file for your mock
virtual environment in an mdtest. (You get a lot of diagnostics about
Python syntax errors in the `pyvenv.cfg` file, otherwise!)
- Rewrites the test added in
https://github.com/astral-sh/ruff/pull/17178 as an mdtest, and deletes
the original test that was added in that PR
## Test Plan
I verified that the new mdtest fails if I revert the changes to
`resolver.rs` that were added in
https://github.com/astral-sh/ruff/pull/17178
For two non-disjoint types `P` and `Q`, the simplification of `(P | Q) &
~Q` is not `P`, but `P & ~Q`. In other words, the non-empty set `P & Q`
is also excluded from the type.
The same applies for a constrained typevar `[T: (P, Q)]`: `T & ~Q`
should simplify to `P & ~Q`, not just `P`.
Implementing this is actually purely a matter of removing code from the
constrained typevar simplification logic; we just need to not bother
removing the negations. If the negations are actually redundant (because
the constraint types are disjoint), normal intersection simplification
will already eliminate them (as shown in the added test.)
This adds a new `Type` variant for holding an instance of a typevar
inside of a generic function or class. We don't handle specializing the
typevars yet, but this should implement most of the typing rules for
inside the generic function/class, where we don't know yet which
specific type the typevar will be specialized to.
This PR does _not_ yet handle the constraint that multiple occurrences
of the typevar must be specialized to the _same_ time. (There is an
existing test case for this in `generics/functions.md` which is still
marked as TODO.)
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
This PR changes the inferred type for symbols in unreachable sections of
code to `Never` (instead of reporting them as unbound), in order to
silence false positive diagnostics. See the lengthy comment in the code
for further details.
## Test Plan
- Updated Markdown tests.
- Manually verified a couple of ecosystem diagnostic changes.
Fixes#17164. Simply checking whether one type is gradually equivalent
to another is too simplistic here: `Any` is gradually equivalent to
`Todo`, but we should permit users to cast from `Todo` or `Unknown` to
`Any` without complaining about it. This changes our logic so that we
only complain about redundant casts if:
- the two types are exactly equal (when normalized) OR they are
equivalent (we'll still complain about `Any -> Any` casts, and about
`Any | str | int` -> `str | int | Any` casts, since their normalized
forms are exactly equal, even though the type is not fully static -- and
therefore does not participate in equivalence relations)
- AND the casted type does not contain `Todo`
## Summary
The existing signature for `str` calls had various problems, one of
which I noticed while looking at some ecosystem projects (`scrapy`,
added as a project to mypy_primer in this PR).
## Test Plan
- New tests for `str(…)` calls.
- Observed reduction of false positives in ecosystem checks
## Summary
A callable type is disjoint from other literal types. For example,
`Type::StringLiteral` must be an instance of exactly `str`, not a
subclass of `str`, and `str` is not callable. The same applies to other
literal types.
This should hopefully fix#17144, I couldn't produce any failures after
running property tests multiple times.
## Test Plan
Add test cases for disjointness check between callable and other literal
types.
Run property tests multiple times.
## Summary
Python `**` works differently to Rust `**`!
## Test Plan
Added an mdtest for various edge cases, and checked in the Python REPL
that we infer the correct type in all the new cases tested.
## Summary
Fixes https://github.com/astral-sh/ruff/issues/17058.
Equivalent callable types were not understood as equivalent when they
appeared nested inside unions and intersections. This PR fixes that by
ensuring that `Callable` elements nested inside unions, intersections
and tuples have their representations normalized before one union type
is compared with another for equivalence, or before one intersection
type is compared with another for equivalence.
The normalizations applied to a `Callable` type are:
- the type of the default value is stripped from all parameters (only
whether the parameter _has_ a default value is relevant to whether one
`Callable` type is equivalent to another)
- The names of the parameters are stripped from positional-only
parameters, variadic parameters and keyword-variadic parameters
- Unions and intersections that are present (top-level or nested) inside
parameter annotations or return annotations are normalized.
Adding a `CallableType::normalized()` method also allows us to simplify
the implementation of `CallableType::is_equivalent_to()`.
### Should these normalizations be done eagerly as part of a
`CallableType` constructor?
I considered this. It's something that we could still consider doing in
the future; this PR doesn't rule it out as a possibility. However, I
didn't pursue it for now, for several reasons:
1. Our current `Display` implementation doesn't handle well the
possibility that a parameter might not have a name or an annotated type.
Callable types with parameters like this would be displayed as follows:
```py
(, ,) -> None: ...
```
That's fixable! It could easily become something like `(Unknown,
Unknown) -> None: ...`. But it also illustrates that we probably want to
retain the parameter names when displaying the signature of a `lambda`
function if you're hovering over a reference to the lambda in an IDE.
Currently we don't have a `LambdaType` struct for representing `lambda`
functions; if we wanted to eagerly normalize signatures when creating
`CallableType`s, we'd probably have to add a `LambdaType` struct so that
we would retain the full signature of a `lambda` function, rather than
representing it as an eagerly simplified `CallableType`.
2. In order to ensure that it's impossible to create `CallableType`s
without the parameters being normalized, I'd either have to create an
alternative `SimplifiedSignature` struct (which would duplicate a lot of
code), or move `CallableType` to a new module so that the only way of
constructing a `CallableType` instance would be via a constructor method
that performs the normalizations eagerly on the callable's signature.
Again, this isn't a dealbreaker, and I think it's still an option, but
it would be a lot of churn, and it didn't seem necessary for now. Doing
it this way, at least to start with, felt like it would create a diff
that's easier to review and felt like it would create fewer merge
conflicts for others.
## Test Plan
- Added a regression mdtest for
https://github.com/astral-sh/ruff/issues/17058
- Ran `QUICKCHECK_TESTS=1000000 cargo test --release -p
red_knot_python_semantic -- --ignored types::property_tests::stable`
## Summary
Add an initial set of tests that will eventually document our behavior
around unreachable code. In the last section of this suite, I argue why
we should never type check unreachable sections and never emit any
diagnostics in these sections.
## Summary
With this PR, we emit a diagnostic for this case where
previously didn't:
```py
from typing import Literal
def f(m: int, n: Literal[-1, 0, 1]):
# error: [division-by-zero] "Cannot divide object of type `int` by zero"
return m / n
```
## Test Plan
New Markdown test
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## Summary
from https://github.com/astral-sh/ruff/pull/17034#discussion_r2024222525
This is a simple PR to fix the invalid behavior of `NotImplemented` on
Python >=3.10.
## Test Plan
I think it would be better if we could run mdtest across multiple Python
versions in GitHub Actions.
<!-- How was it tested? -->
---------
Co-authored-by: David Peter <sharkdp@users.noreply.github.com>
## Summary
Add support for decorators on function as well as support
for properties by adding special handling for `@property` and `@<name of
property>.setter`/`.getter` decorators.
closes https://github.com/astral-sh/ruff/issues/16987
## Ecosystem results
- ✔️ A lot of false positives are fixed by our new
understanding of properties
- 🔴 A bunch of new false positives (typically
`possibly-unbound-attribute` or `invalid-argument-type`) occur because
we currently do not perform type narrowing on attributes. And with the
new understanding of properties, this becomes even more relevant. In
many cases, the narrowing occurs through an assertion, so this is also
something that we need to implement to get rid of these false positives.
- 🔴 A few new false positives occur because we do not
understand generics, and therefore some calls to custom setters fail.
- 🔴 Similarly, some false positives occur because we do not
understand protocols yet.
- ✔️ Seems like a true positive to me. [The
setter](e624d8edfa/src/packaging/specifiers.py (L752-L754))
only accepts `bools`, but `None` is assigned in [this
line](e624d8edfa/tests/test_specifiers.py (L688)).
```
+ error[lint:invalid-assignment]
/tmp/mypy_primer/projects/packaging/tests/test_specifiers.py:688:9:
Invalid assignment to data descriptor attribute `prereleases` on type
`SpecifierSet` with custom `__set__` method
```
- ✔️ This is arguable also a true positive. The setter
[here](0c6c75644f/rich/table.py (L359-L363))
returns `Table`, but typeshed wants [setters to return
`None`](bf8d2a9912/stdlib/builtins.pyi (L1298)).
```
+ error[lint:invalid-argument-type]
/tmp/mypy_primer/projects/rich/rich/table.py:359:5: Object of type
`Literal[padding]` cannot be assigned to parameter 2 (`fset`) of bound
method `setter`; expected type `(Any, Any, /) -> None`
```
## Follow ups
- Fix the `@no_type_check` regression
- Implement class decorators
## Test Plan
New Markdown test suites for decorators and properties.
## Summary
Part of #15382, this PR adds support for disjointness between two
callable types. They are never disjoint because there exists a callable
type that's a subtype of all other callable types:
```py
(*args: object, **kwargs: object) -> Never
```
The `Never` is a subtype of every fully static type thus a callable type
that has the return type of `Never` means that it is a subtype of every
return type.
## Test Plan
Add test cases related to mixed parameter kinds, gradual form (`...`)
and `Never` type.
## Summary
Currently our `Type::Callable` wraps a four-variant `CallableType` enum.
But as time has gone on, I think we've found that the four variants in
`CallableType` are really more different to each other than they are
similar to each other:
- `GeneralCallableType` is a structural type describing all callable
types with a certain signature, but the other three types are "literal
types", more similar to the `FunctionLiteral` variant
- `GeneralCallableType` is not a singleton or a single-valued type, but
the other three are all single-valued types
(`WrapperDescriptorDunderGet` is even a singleton type)
- `GeneralCallableType` has (or should have) ambiguous truthiness, but
all possible inhabitants of the other three types are always truthy.
- As a structural type, `GeneralCallableType` can contain inner unions
and intersections that must be sorted in some contexts in our internal
model, but this is not true for the other three variants.
This PR flattens `Type::Callable` into four distinct `Type::` variants.
In the process, it fixes a number of latent bugs that were concealed by
the current architecture but are laid bare by the refactor. Unit tests
for these bugs are included in the PR.
## Summary
This PR fixes a bug in callable subtyping to consider both the
positional and keyword form of the standard parameter in the supertype
when matching against variadic, keyword-only and keyword-variadic
parameter in the subtype.
This is done by collecting the unmatched standard parameters and then
checking them against the keyword-only / keyword-variadic parameters
after the positional loop.
## Test Plan
Add test cases.
## Summary
There are quite a few places we infer `Todo` types currently, and some
of them are nested somewhat deeply in type expressions. These can cause
spurious issues for the new `redundant-cast` diagnostics. We fixed all
the false positives we saw in the mypy_primer report before merging
https://github.com/astral-sh/ruff/pull/17100, but I think there are
still lots of places where we'd emit false positives due to this check
-- we currently don't run on that many projects at all in our
mypy_primer check:
d0c8eaa092/.github/workflows/mypy_primer.yaml (L71)
This PR fixes some more false positives from this diagnostic by making
the `Type::contains_todo()` method more expansive.
## Test Plan
I added a regression test which causes us to emit a spurious diagnostic
on `main`, but does not with this PR.
## Summary
I noticed we were inferring `Todo` as the declared type for annotations
such as `x: tuple[list[int], list[int]]`. This PR reworks our annotation
parsing so that we instead infer `tuple[Todo, Todo]` for this
annotation, which is quite a bit more precise.
## Test Plan
Existing mdtest updated.
## Summary
Following up from earlier discussion on Discord, this PR adds logic to
flag casts as redundant when the inferred type of the expression is the
same as the target type. It should follow the semantics from
[mypy](https://github.com/python/mypy/pull/1705).
Example:
```python
def f() -> int:
return 10
# error: [redundant-cast] "Value is already of type `int`"
cast(int, f())
```
## Summary
Part of #13694
Seems there a bit more to cover regarding `in` and other types, but i
can cover them in different PRs
## Test Plan
Add `in.md` file in narrowing conditionals folder
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
In preparation for #17017, where we will need them to suppress new false
positives (once we understand the `ParamSpec.args`/`ParamSpec.kwargs`
properties).
## Test Plan
Tested on branch #17017
## Summary
A quick fix for how union/intersection member search ins performed in
Knot.
## Test Plan
* Added a dunder method call test for Union, which exhibits the error
* Also added an intersection error, but it is not triggering currently
due to `call` logic not being fully implemented for intersections.
---------
Co-authored-by: David Peter <mail@david-peter.de>
## Summary
Closes#16661
This PR includes two changes:
- `NotImplementedType` is now a member of `KnownClass`
- We skip `is_assignable_to` checks for `NotImplemented` when checking
return types
### Limitation
```py
def f(cond: bool) -> int:
return 1 if cond else NotImplemented
```
The implementation covers cases where `NotImplemented` appears inside a
`Union`.
However, for more complex types (ex. `Intersection`) it will not worked.
In my opinion, supporting such complexity is unnecessary at this point.
## Test Plan
Two `mdtest` files were updated:
- `mdtest/function/return_type.md`
- `mdtest/type_properties/is_singleton.md`
To test `KnownClass`, run:
```bash
cargo test -p red_knot_python_semantic -- types::class::
```
## Summary
From #16861, and the continuation of #16915.
This PR fixes the incorrect behavior of
`TypeInferenceBuilder::infer_name_load` in eager nested scopes.
And this PR closes#16341.
## Test Plan
New test cases are added in `annotations/deferred.md`.
## Summary
Part of #13694
Narrow in or-patterns by taking the type union of the type constraints
in each disjunct pattern.
## Test Plan
Add new tests to narrow/match.md
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
Part of #13694
The implementation here was suspiciously straightforward so please lmk
if I missed something
Also some drive-by changes to DRY things up a bit
## Test Plan
Add new tests to narrow/match.md
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
This PR adds some branches so that we infer `Todo` types for attribute
access on instances of `super()` and subtypes of `type[Enum]`. It reduces
false positives in the short term until we implement full support for
these features.
## Test Plan
New mdtests added + mypy_primer report
## Summary
Mainly for partially fixing #16953
## Test Plan
Update is_subtype tests. And should maybe do these checks for many other
types (is subtype of object but object is not subtype)
---------
Co-authored-by: Dhruv Manilawala <dhruvmanila@gmail.com>
## Summary
Further work towards https://github.com/astral-sh/ruff/issues/14169.
We currently panic on encountering cyclic `*` imports. This is easily
fixed using fixpoint iteration.
## Test Plan
Added a test that panics on `main`, but passes with this PR
## Summary
As mentioned in
https://github.com/astral-sh/ruff/pull/16698#discussion_r2004920075,
part of #15382, this PR updates the `is_gradual_equivalent_to`
implementation between callable types to be similar to
`is_equivalent_to` and checks other attributes of parameters like name,
optionality, and parameter kind.
## Test Plan
Expand the existing test cases to consider other properties but not all
similar to how the tests are structured for subtyping and assignability.
## Summary
This PR adds initial support for `*` imports to red-knot. The approach
is to implement a standalone query, called from semantic indexing, that
visits the module referenced by the `*` import and collects all
global-scope public names that will be imported by the `*` import. The
`SemanticIndexBuilder` then adds separate definitions for each of these
names, all keyed to the same `ast::Alias` node that represents the `*`
import.
There are many pieces of `*`-import semantics that are still yet to be
done, even with this PR:
- This PR does not attempt to implement any of the semantics to do with
`__all__`. (If a module defines `__all__`, then only the symbols
included in `__all__` are imported, _not_ all public global-scope
symbols.
- With the logic implemented in this PR as it currently stands, we
sometimes incorrectly consider a symbol bound even though it is defined
in a branch that is statically known to be dead code, e.g. (assuming the
target Python version is set to 3.11):
```py
# a.py
import sys
if sys.version_info < (3, 10):
class Foo: ...
```
```py
# b.py
from a import *
print(Foo) # this is unbound at runtime on 3.11,
# but we currently consider it bound with the logic in this PR
```
Implementing these features is important, but is for now deferred to
followup PRs.
Many thanks to @ntBre, who contributed to this PR in a pairing session
on Friday!
## Test Plan
Assertions in existing mdtests are adjusted, and several new ones are
added.
## Summary
Here I fix the last English spelling errors I could find in the repo.
Again, I am trying not to touch variable/function names, or anything
that might be misspelled in the API. The goal is to make this PR safe
and easy to merge.
## Test Plan
I have run all the unit tests. Though, again, all of the changes I make
here are to docs and docstrings. I make no code changes, which I believe
should greatly mitigate the testing concerns.
## Summary
Resolves#16895.
`abstractmethod` is now a `KnownFunction`. When a function is decorated
by `abstractmethod` or when the parent class inherits directly from
`Protocol`, `invalid-return-type` won't be emitted for that function.
## Test Plan
Markdown tests.
---------
Co-authored-by: Carl Meyer <carl@oddbird.net>
## Summary
Fixes#16912
Create a new type `DisplayMaybeParenthesizedType` that is now used in
Union and Intersection display
## Test Plan
Update callable annotations
## Summary
From #16861
This PR fixes the incorrect `ClassDef` handling of
`SemanticIndexBuilder::visit_stmt`, which fixes some of the incorrect
behavior of referencing the class itself in the class scope (a complete
fix requires a different fix, which will be done in the another PR).
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
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## Summary
This is a cleanup PR. I am fixing various English language spelling
errors. This is mostly in docs and docstrings.
## Test Plan
The usual CI tests were run. I tried to build the docs (though I had
some troubles there). The testing needs here are, I trust, very low
impact. (Though I would happily test more.)
## Summary
Part of #15382, this PR adds support for calling a variable that's
annotated with `typing.Callable`.
## Test Plan
Add test cases in a new `call/annotation.md` file.
## Summary
Part of #15382
This PR adds support for checking the assignability of two general
callable types.
This is built on top of #16804 by including the gradual parameters check
and accepting a function that performs the check between the two types.
## Test Plan
Update `is_assignable_to.md` with callable types section.
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## Summary
When callables are displayed in unions, like:
```py
from typing import Callable
def foo(x: Callable[[], int] | None):
# red-knot: Revealed type is `() -> int | None` [revealed-type]
reveal_type(x)
```
This leaves the type rather ambiguous, to fix this we can add
parenthesis to callable type in union
Fixes#16893
## Test Plan
Update callable annotations tests
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
This PR removes false-positive diagnostics for `*` imports. Currently we
always emit a diagnostic for these statements unless the module we're
importing from has a symbol named `"*"` in its symbol table for the
global scope. (And if we were doing everything correctly, no module ever
would have a symbol named `"*"` in its global scope!)
The fix here is sort-of hacky and won't be what we'll want to do
long-term. However, I think it's useful to do this as a first step
since:
- It significantly reduces false positives when running on code that
uses `*` imports
- It "resets" the tests to a cleaner state with many fewer TODOs, making
it easier to see what the hard work is that's still to be done.
## Test Plan
`cargo test -p red_knot_python_semantic`
Carl Meyer
Dhruv Manilawala
Eric Mark Martin
Matthew Mckee
Alex Waygood
Brent Westbrook
David Peter
Douglas Creager
cake-monotone
Mike Perlov
Shunsuke Shibayama
Andrew Gallant
Micha Reiser
Trevor Manz
John Stilley
InSync