## Summary
This PR fixes a panic which can occur in an unpack assignment when:
* (number of target expressions) - (number of tuple types) > 2
* There's a starred expression
The reason being that the `insert` panics because the index is greater
than the length.
This is an error case and so practically it should occur very rarely.
The solution is to resize the types vector to match the number of
expressions and then insert the starred expression type.
## Test Plan
Add a new test case.
## Summary
This PR creates a new `TypeCheckDiagnosticsBuilder` for the
`TypeCheckDiagnostics` struct. The main motivation behind this is to
separate the helpers required to build the diagnostics from the type
inference builder itself. This allows us to use such helpers outside of
the inference builder like for example in the unpacking logic in
https://github.com/astral-sh/ruff/pull/13979.
## Test Plan
`cargo insta test`
## Summary
These cases aren't handled correctly yet -- some of them are waiting on
refactors to `Unbound` before fixing. Part of #12699.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
I noticed that augmented assignments on floats were yielding "not
supported" diagnostics. If the dunder isn't bound at all, we should use
binary operator semantics, rather than treating it as not-callable.
## Summary
Minor follow-up to #13917 — thanks @AlexWaygood for the post-merge
review.
- Add
SliceLiteralType::as_tuple
- Use .expect() instead of SAFETY
comment
- Match on ::try_from
result
- Add TODO comment regarding raising a diagnostic for `"foo"["bar":"baz"]`
## Summary
This PR adds support for heterogenous `tuple` annotations to red-knot.
It does the following:
- Extends `infer_type_expression` so that it understands tuple
annotations
- Changes `infer_type_expression` so that `ExprStarred` nodes in type
annotations are inferred as `Todo` rather than `Unknown` (they're valid
in PEP-646 tuple annotations)
- Extends `Type::is_subtype_of` to understand when one heterogenous
tuple type can be understood to be a subtype of another (without this
change, the PR would have introduced new false-positive errors to some
existing mdtests).
## Summary
- Add a new `Type::SliceLiteral` variant
- Infer `SliceLiteral` types for slice expressions, such as
`<int-literal>:<int-literal>:<int-literal>`.
- Infer "sliced" literal types for subscript expressions using slices,
such as `<string-literal>[<slice-literal>]`.
- Infer types for expressions involving slices of tuples:
`<tuple>[<slice-literal>]`.
closes#13853
## Test Plan
- Unit tests for indexing/slicing utility functions
- Markdown-based tests for
- Subscript expressions `tuple[slice]`
- Subscript expressions `string_literal[slice]`
- Subscript expressions `bytes_literal[slice]`
## Summary
This does two things:
- distribute negated intersections when building up intersections (i.e.
going from `A & ~(B & C)` to `(A & ~B) | (A & ~C)`) (fixing #13931)
## Test Plan
`cargo test`
## Summary
This PR adds type narrowing in `and` and `or` expressions, for example:
```py
class A: ...
x: A | None = A() if bool_instance() else None
isinstance(x, A) or reveal_type(x) # revealed: None
```
## Test Plan
New mdtests 😍
## Summary
After #13918 has landed, narrowing constraint negation became easy, so
adding support for `not` operator.
## Test Plan
Added a new mdtest file for `not` expression.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
As python uses short-circuiting boolean operations in runtime, we should
mimic that logic in redknot as well.
For example, we should detect that in the following code `x` might be
undefined inside the block:
```py
if flag or (x := 1):
print(x)
```
## Test Plan
Added mdtest suit for boolean expressions.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
Add support for type narrowing in elif and else scopes as part of
#13694.
## Test Plan
- mdtest
- builder unit test for union negation.
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
Add type narrowing for `isinstance(object, classinfo)` [1] checks:
```py
x = 1 if flag else "a"
if isinstance(x, int):
reveal_type(x) # revealed: Literal[1]
```
closes#13893
[1] https://docs.python.org/3/library/functions.html#isinstance
## Test Plan
New Markdown-based tests in `narrow/isinstance.md`.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
A minor quality-of-life improvement: add
[`#[track_caller]`](https://doc.rust-lang.org/reference/attributes/codegen.html#the-track_caller-attribute)
attribute to `Type::expect_xyz()` methods and some `TypeInference` methods such that the panic-location
is reported one level higher up in the stack trace.
before: reports location inside the `Type::expect_class_literal()`
method. Not very useful.
```
thread 'types::infer::tests::deferred_annotation_builtin' panicked at crates/red_knot_python_semantic/src/types.rs:304:14:
Expected a Type::ClassLiteral variant
```
after: reports location at the `Type::expect_class_literal()` call site,
where the error was made.
```
thread 'types::infer::tests::deferred_annotation_builtin' panicked at crates/red_knot_python_semantic/src/types/infer.rs:4302:14:
Expected a Type::ClassLiteral variant
```
## Test Plan
Called `expect_class_literal()` on something that's not a
`Type::ClassLiteral` and saw that the error was reported at the call
site.
## Summary
* Rename `Type::Class` => `Type::ClassLiteral`
* Rename `Type::Function` => `Type::FunctionLiteral`
* Do not rename `Type::Module`
* Remove `*Literal` suffixes in `display::LiteralTypeKind` variants, as
per clippy suggestion
* Get rid of `Type::is_class()` in favor of `is_subtype_of(…, 'type')`;
modifiy `is_subtype_of` to support this.
* Add new `Type::is_xyz()` methods and use them instead of matching on
`Type` variants.
closes#13863
## Test Plan
New `is_subtype_of_class_literals` unit test.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
- Properly treat the empty intersection as being of type `object`.
- Consequently, change the simplification method to explicitly add
`Never` to the positive side of the intersection when collapsing a type
such as `int & str` to `Never`, as opposed to just clearing both the
positive and the negative side.
- Minor code improvement in `bindings_ty`: use `peekable()` to check
whether the iterator over constraints is empty, instead of handling
first and subsequent elements separately.
fixes#13870
## Test Plan
- New unit tests for `IntersectionBuilder` to make sure the empty
intersection represents `object`.
- Markdown-based regression test for the original issue in #13870
Add the following subtype relations:
- `BooleanLiteral <: object`
- `IntLiteral <: object`
- `StringLiteral <: object`
- `LiteralString <: object`
- `BytesLiteral <: object`
Added a test case for `bool <: int`.
## Test Plan
New unit tests.
Add type narrowing for `!=` expression as stated in
#13694.
### Test Plan
Add tests in new md format.
---------
Co-authored-by: David Peter <mail@david-peter.de>
## Summary
A small fix for comparisons of multiple comparators.
Instead of comparing each comparator to the leftmost item, we should
compare it to the closest item on the left.
While implementing this, I noticed that we don’t yet narrow Yoda
comparisons (e.g., `True is x`), so I didn’t change that behavior in
this PR.
## Test Plan
Added some mdtests 🎉
## Summary
Just a drive-by change that occurred to me while I was looking at
`Type::is_subtype_of`: the existing pattern for unions on the *right
hand side*:
```rs
(ty, Type::Union(union)) => union
.elements(db)
.iter()
.any(|&elem_ty| ty.is_subtype_of(db, elem_ty)),
```
is not (generally) correct if the *left hand side* is a union.
## Test Plan
Added new test cases for `is_subtype_of` and `!is_subtype_of`
## Summary
- Consistent naming: `BoolLiteral` => `BooleanLiteral` (it's mainly the
`Ty::BoolLiteral` variant that was renamed)
I tripped over this a few times now, so I thought I'll smooth it out.
- Add a new test case for `Literal[True] <: bool`, as suggested here:
https://github.com/astral-sh/ruff/pull/13781#discussion_r1804922827
Remove unnecessary uses of `.as_ref()`, `.iter()`, `&**` and similar, mostly in situations when iterating over variables. Many of these changes are only possible following #13826, when we bumped our MSRV to 1.80: several useful implementations on `&Box<[T]>` were only stabilised in Rust 1.80. Some of these changes we could have done earlier, however.
Implemented some points from
https://github.com/astral-sh/ruff/issues/12701
- Handle Unknown and Any in Unary operation
- Handle Boolean in binary operations
- Handle instances in unary operation
- Consider division by False to be division by zero
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
- Refactored comparison type inference functions in `infer.rs`: Changed
the return type from `Option` to `Result` to lay the groundwork for
providing more detailed diagnostics.
- Updated diagnostic messages.
This is a small step toward improving diagnostics in the future.
Please refer to #13787
## Test Plan
mdtest included!
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
## Summary
This fixes an edge case that @carljm and I missed when implementing
https://github.com/astral-sh/ruff/pull/13800. Namely, if the left-hand
operand is the _exact same type_ as the right-hand operand, the
reflected dunder on the right-hand operand is never tried:
```pycon
>>> class Foo:
... def __radd__(self, other):
... return 42
...
>>> Foo() + Foo()
Traceback (most recent call last):
File "<python-input-1>", line 1, in <module>
Foo() + Foo()
~~~~~~^~~~~~~
TypeError: unsupported operand type(s) for +: 'Foo' and 'Foo'
```
This edge case _is_ covered in Brett's blog at
https://snarky.ca/unravelling-binary-arithmetic-operations-in-python/,
but I missed it amongst all the other subtleties of this algorithm. The
motivations and history behind it were discussed in
https://mail.python.org/archives/list/python-dev@python.org/thread/7NZUCODEAPQFMRFXYRMGJXDSIS3WJYIV/
## Test Plan
I added an mdtest for this cornercase.
## Summary
- Add `Type::is_disjoint_from` as a way to test whether two types
overlap
- Add a first set of simplification rules for intersection types
- `S & T = S` for `S <: T`
- `S & ~T = Never` for `S <: T`
- `~S & ~T = ~T` for `S <: T`
- `A & ~B = A` for `A` disjoint from `B`
- `A & B = Never` for `A` disjoint from `B`
- `bool & ~Literal[bool] = Literal[!bool]`
resolves one item in #12694
## Open questions:
- Can we somehow leverage the (anti) symmetry between `positive` and
`negative` contributions? I could imagine that there would be a way if
we had `Type::Not(type)`/`Type::Negative(type)`, but with the
`positive`/`negative` architecture, I'm not sure. Note that there is a
certain duplication in the `add_positive`/`add_negative` functions (e.g.
`S & ~T = Never` is implemented twice), but other rules are actually not
perfectly symmetric: `S & T = S` vs `~S & ~T = ~T`.
- I'm not particularly proud of the way `add_positive`/`add_negative`
turned out. They are long imperative-style functions with some
mutability mixed in (`to_remove`). I'm happy to look into ways to
improve this code *if we decide to go with this approach* of
implementing a set of ad-hoc rules for simplification.
- ~~Is it useful to perform simplifications eagerly in
`add_positive`/`add_negative`? (@carljm)~~ This is what I did for now.
## Test Plan
- Unit tests for `Type::is_disjoint_from`
- Observe changes in Markdown-based tests
- Unit tests for `IntersectionBuilder::build()`
---------
Co-authored-by: Carl Meyer <carl@astral.sh>
Minor cleanup and consistent formatting of the Markdown-based tests.
- Removed lots of unnecessary `a`, `b`, `c`, … variables.
- Moved test assertions (`# revealed:` comments) closer to the tested
object.
- Always separate `# revealed` and `# error` comments from the code by
two spaces, according to the discussion
[here](https://github.com/astral-sh/ruff/pull/13746/files#r1799385758).
This trades readability for consistency in some cases.
- Fixed some headings
