## Summary
This PR is a more holistic fix for
https://github.com/astral-sh/ruff/issues/9534 and
https://github.com/astral-sh/ruff/issues/9159.
When we visit the AST, we track nodes that we need to visit _later_
(deferred nodes). For example, when visiting a function, we defer the
function body, since we don't want to visit the body until we've visited
the rest of the statements in the containing scope.
However, deferred nodes can themselves contain deferred nodes... For
example, a function body can contain a lambda (which contains a deferred
body). And then there are rarer cases, like a lambda inside of a type
annotation.
The aforementioned issues were fixed by reordering the deferral visits
to catch common cases. But even with those fixes, we still fail on cases
like:
```python
from __future__ import annotations
import re
from typing import cast
cast(lambda: re.match, 1)
```
Since we don't expect lambdas to appear inside of type definitions.
This PR modifies the `Checker` to keep visiting until all the deferred
stacks are empty. We _already_ do this for any one kind of deferred
node; now, we do it for _all_ of them at a level above.
## Summary
This is effectively the same problem as
https://github.com/astral-sh/ruff/pull/9175. And this just papers over
it again, though I'm gonna try a more holistic fix in a follow-up PR.
The _real_ fix here is that we need to continue to visit deferred items
until they're exhausted since, e.g., we still get this case wrong
(flagging `re` as unused):
```python
import re
cast(lambda: re.match, 1)
```
Closes https://github.com/astral-sh/ruff/issues/9534.
## Summary
On `main`, we flag redefinitions in cases like:
```python
import os
x = 1
if x > 0:
import os
```
That is, we consider these to be in the "same branch", since they're not
in disjoint branches. This matches Flake8's behavior, but it seems to
lead to false positives.
## Summary
Ensures that any lint rules that include line locations render them as
relative to the cell (and include the cell number) when inside a Jupyter
notebook.
Closes https://github.com/astral-sh/ruff/issues/6672.
## Test Plan
`cargo test`
## Summary
`display` is a special-cased builtin in IPython. This PR adds it to the
builtin namespace when analyzing IPython notebooks.
Closes https://github.com/astral-sh/ruff/issues/8702.
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## Summary
In https://github.com/astral-sh/ruff/pull/7968, I introduced a
regression whereby we started to treat imports used _only_ in type
annotation bounds (with `__future__` annotations) as unused.
The root of the issue is that I started using `visit_annotation` for
these bounds. So we'd queue up the bound in the list of deferred type
parameters, then when visiting, we'd further queue it up in the list of
deferred type annotations... Which we'd then never visit, since deferred
type annotations are visited _before_ deferred type parameters.
Anyway, the better solution here is to use a dedicated flag for these,
since they have slightly different behavior than type annotations.
I've also fixed what I _think_ is a bug whereby we previously failed to
resolve `Callable` in:
```python
type RecordCallback[R: Record] = Callable[[R], None]
from collections.abc import Callable
```
IIUC, the values in type aliases should be evaluated lazily, like type
parameters.
Closes https://github.com/astral-sh/ruff/issues/8017.
## Test Plan
`cargo test`
## Summary
Given:
```python
baz: Annotated[
str,
[qux for qux in foo],
]
```
We treat `baz` as `BindingKind::Annotation`, to ensure that references
to `baz` are marked as unbound. However, we were _also_ treating `qux`
as `BindingKind::Annotation`, which meant that the load in the
comprehension _also_ errored.
Closes https://github.com/astral-sh/ruff/issues/7879.