Commit Graph

74 Commits

Author SHA1 Message Date
Micha Reiser 9ae698fe30
Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
Dylan 965a4dd731
[`isort`] Check full module path against project root(s) when categorizing first-party (#16565)
When attempting to determine whether `import foo.bar.baz` is a known
first-party import relative to [user-provided source
paths](https://docs.astral.sh/ruff/settings/#src), when `preview` is
enabled we now check that `SRC/foo/bar/baz` is a directory or
`SRC/foo/bar/baz.py` or `SRC/foo/bar/baz.pyi` exist.

Previously, we just checked the analogous thing for `SRC/foo`, but this
can be misleading in situations with disjoint namespace packages that
share a common base name (e.g. we may be working inside the namespace
package `foo.buzz` and importing `foo.bar` from elsewhere).

Supersedes #12987 
Closes #12984
2025-05-05 11:40:01 -05:00
Garrett Reynolds dc491e8ade
[`ruff`] Fix false positive on global keyword (`RUF052`) (#15235) 2025-01-14 08:36:40 +01:00
Alex Waygood f3d8c023d3
[`ruff`] Avoid emitting `assignment-in-assert` when all references to the assigned variable are themselves inside `assert`s (`RUF018`) (#14661) 2024-11-29 13:36:59 +00:00
Micha Reiser b63c2e126b
Upgrade Rust toolchain to 1.83 (#14677) 2024-11-29 12:05:05 +00:00
David Salvisberg 6fd10e2fe7
[`flake8-type-checking`] Adds implementation for TC007 and TC008 (#12927)
Co-authored-by: Simon Brugman <sbrugman@users.noreply.github.com>
Co-authored-by: Carl Meyer <carl@oddbird.net>
2024-11-27 09:51:20 +01:00
Simon Brugman 84d4f114ef
Use bitshift consistently for bitflag definitions (#14265) 2024-11-11 10:20:17 +00:00
Micha Reiser 9f3a38d408
Extract `LineIndex` independent methods from `Locator` (#13938) 2024-10-28 07:53:41 +00:00
Alex Waygood d380b37a09
Add a new `Binding::is_unused` method (#12729) 2024-08-07 11:17:56 +01:00
Alex Waygood 928ffd6650
Ignore `NPY201` inside `except` blocks for compatibility with older numpy versions (#12490) 2024-07-24 20:03:23 +00:00
Charlie Marsh 30cef67b45
Remove `BindingKind::ComprehensionVar` (#12347)
## Summary

This doesn't seem to be used anywhere. Maybe it mattered when we didn't
handle generator scopes properly?
2024-07-16 11:18:04 -04:00
ukyen 068b75cc8e
[`pyflakes`] Detect assignments that shadow definitions (`F811`) (#11961)
## Summary
This PR updates `F811` rule to include assignment as possible shadowed
binding. This will fix issue: #11828 .

## Test Plan

Add a test file, F811_30.py, which includes a redefinition after an
assignment and a verified snapshot file.
2024-06-23 13:29:32 -04:00
plredmond dcabd04caf
F401 use BTreeMap instead of FxHashMap (#11621)
* Potentially resolves #11619 (nondeterministic hashmap order across
different architectures) in F401 by replacing a hashmap with
nondeterministic traversal order with an ordered mapping.

I'm not sure how to test this with our CI/CD. I don't have an s390x
machine at home. Should I try it in Qemu?
2024-05-30 10:54:46 -07:00
Charlie Marsh 69d9212817
Propagate reads on global variables (#11584)
## Summary

This PR ensures that if a variable is bound via `global`, and then the
`global` is read, the originating variable is also marked as read. It's
not perfect, in that it won't detect _rebindings_, like:

```python
from app import redis_connection

def func():
    global redis_connection

    redis_connection = 1
    redis_connection()
```

So, above, `redis_connection` is still marked as unused.

But it does avoid flagging `redis_connection` as unused in:

```python
from app import redis_connection

def func():
    global redis_connection

    redis_connection()
```

Closes https://github.com/astral-sh/ruff/issues/11518.
2024-05-28 14:47:05 -04:00
Micha Reiser 22639c5a2a
Move all module from the AST to the semantic crate (#11330) 2024-05-08 08:56:50 +00:00
Alex Waygood a06ffeb54e
Track ranges of names inside `__all__` definitions (#10525) 2024-03-22 18:38:40 +00:00
Charlie Marsh 10ace88e9a
Track conditional deletions in the semantic model (#10415)
## Summary

Given `del X`, we'll typically add a `BindingKind::Deletion` to `X` to
shadow the current binding. However, if the deletion is inside of a
conditional operation, we _won't_, as in:

```python
def f():
    global X

    if X > 0:
        del X
```

We will, however, track it as a reference to the binding. This PR adds
the expression context to those resolved references, so that we can
detect that the `X` in `global X` was "assigned to".

Closes https://github.com/astral-sh/ruff/issues/10397.
2024-03-14 20:45:46 -04:00
Micha Reiser 8ea5b08700
refactor: Use `QualifiedName` for `Imported::call_path` (#10214)
## Summary

When you try to remove an internal representation leaking into another
type and end up rewriting a simple version of `smallvec`.

The goal of this PR is to replace the `Box<[&'a str]>` with
`Box<QualifiedName>` to avoid that the internal `QualifiedName`
representation leaks (and it gives us a nicer API too). However, doing
this when `QualifiedName` uses `SmallVec` internally gives us all sort
of funny lifetime errors. I was lost but @BurntSushi came to rescue me.
He figured out that `smallvec` has a variance problem which is already
tracked in https://github.com/servo/rust-smallvec/issues/146

To fix the variants problem, I could use the smallvec-2-alpha-4 or
implement our own smallvec. I went with implementing our own small vec
for this specific problem. It obviously isn't as sophisticated as
smallvec (only uses safe code), e.g. it doesn't perform any size
optimizations, but it does its job.

Other changes:

* Removed `Imported::qualified_name` (the version that returns a
`String`). This can be replaced by calling `ToString` on the qualified
name.
* Renamed `Imported::call_path` to `qualified_name` and changed its
return type to `&QualifiedName`.
* Renamed `QualifiedName::imported` to `user_defined` which is the more
common term when talking about builtins vs the rest/user defined
functions.


## Test plan

`cargo test`
2024-03-06 09:55:59 +01:00
Micha Reiser a6d892b1f4
Split `CallPath` into `QualifiedName` and `UnqualifiedName` (#10210)
## Summary

Charlie can probably explain this better than I but it turns out,
`CallPath` is used for two different things:

* To represent unqualified names like `version` where `version` can be a
local variable or imported (e.g. `from sys import version` where the
full qualified name is `sys.version`)
* To represent resolved, full qualified names

This PR splits `CallPath` into two types to make this destinction clear.

> Note: I haven't renamed all `call_path` variables to `qualified_name`
or `unqualified_name`. I can do that if that's welcomed but I first want
to get feedback on the approach and naming overall.

## Test Plan

`cargo test`
2024-03-04 09:06:51 +00:00
Micha Reiser 64f66cd8fe
Refine SemanticModel lifetime bounds (#10221)
## Summary

Corrects/refines some semantic model and related lifetime bounds.

## Test Plan

`cargo check`
2024-03-04 09:21:13 +01:00
Micha Reiser e725b6fdaf
CallPath newtype wrapper (#10201)
## Summary

This PR changes the `CallPath` type alias to a newtype wrapper. 

A newtype wrapper allows us to limit the API and to experiment with
alternative ways to implement matching on `CallPath`s.



## Test Plan

`cargo test`
2024-03-03 16:54:24 +01:00
Charlie Marsh 5bc0d9c324
Add a binding kind for comprehension targets (#9967)
## Summary

I was surprised to learn that we treat `x` in `[_ for x in y]` as an
"assignment" binding kind, rather than a dedicated comprehension
variable.
2024-02-12 20:09:39 -05:00
Charlie Marsh 346a828db2
Add a `BindingKind` for `WithItem` variables (#8594) 2023-11-09 22:44:49 -05:00
Charlie Marsh 0ac124acef
Make unpacked assignment a flag rather than a `BindingKind` (#8595)
## Summary

An assignment can be _both_ (e.g.) a loop variable _and_ assigned via
unpacking. In other words, unpacking is a quality of an assignment, not
a _kind_.
2023-11-09 21:41:30 -05:00
Valeriy Savchenko 26d53c56a2
[refurb] Implement `repeated-append` rule (`FURB113`) (#6702)
## Summary

As an initial effort with replicating `refurb` rules (#1348 ), this PR
adds support for
[FURB113](https://github.com/dosisod/refurb/blob/master/refurb/checks/builtin/list_extend.py)
and adds a new category of checks.

## Test Plan

I included a new test + checked that all other tests pass.
2023-08-28 22:51:59 +00:00
Charlie Marsh fc89976c24
Move `Ranged` into `ruff_text_size` (#6919)
## Summary

The motivation here is that this enables us to implement `Ranged` in
crates that don't depend on `ruff_python_ast`.

Largely a mechanical refactor with a lot of regex, Clippy help, and
manual fixups.

## Test Plan

`cargo test`
2023-08-27 14:12:51 -04:00
Charlie Marsh 424b8d4ad2
Use a single node hierarchy to track statements and expressions (#6709)
## Summary

This PR is a follow-up to the suggestion in
https://github.com/astral-sh/ruff/pull/6345#discussion_r1285470953 to
use a single stack to store all statements and expressions, rather than
using separate vectors for each, which gives us something closer to a
full-fidelity chain. (We can then generalize this concept to include all
other AST nodes too.)

This is in part made possible by the removal of the hash map from
`&Stmt` to `StatementId` (#6694), which makes it much cheaper to store
these using a single interface (since doing so no longer introduces the
requirement that we hash all expressions).

I'll follow-up with some profiling, but a few notes on how the data
requirements have changed:

- We now store a `BranchId` for every expression, not just every
statement, so that's an extra `u32`.
- We now store a single `NodeId` on every snapshot, rather than separate
`StatementId` and `ExpressionId` IDs, so that's one fewer `u32` for each
snapshot.
- We're probably doing a few more lookups in general, since any calls to
`current_statement()` etc. now have to iterate up the node hierarchy
until they identify the first statement.

## Test Plan

`cargo test`
2023-08-21 21:32:57 -04:00
Charlie Marsh db1c556508
Implement `Ranged` on more structs (#6639)
## Summary

I noticed some inconsistencies around uses of `.range.start()`, structs
that have a `TextRange` field but don't implement `Ranged`, etc.

## Test Plan

`cargo test`
2023-08-17 11:22:39 -04:00
Charlie Marsh a2758513de
Fix false-positive in submodule resolution (#6435)
Closes https://github.com/astral-sh/ruff/issues/6433.
2023-08-09 02:36:39 +00:00
Charlie Marsh b21abe0a57
Use separate structs for expression and statement tracking (#6351)
## Summary

This PR fixes the performance degradation introduced in
https://github.com/astral-sh/ruff/pull/6345. Instead of using the
generic `Nodes` structs, we now use separate `Statement` and
`Expression` structs. Importantly, we can avoid tracking a bunch of
state for expressions that we need for parents: we don't need to track
reference-to-ID pointers (we just have no use-case for this -- I'd
actually like to remove this from statements too, but we need it for
branch detection right now), we don't need to track depth, etc.

In my testing, this entirely removes the regression on all-rules, and
gets us down to 2ms slower on the default rules (as a crude hyperfine
benchmark, so this is within margin of error IMO).

No behavioral changes.
2023-08-07 15:27:42 +00:00
Charlie Marsh 61d3977f95
Make the `statement` vector private on `SemanticModel` (#6348)
## Summary

Instead, expose these as methods, now that we can use a reasonable
nomenclature on the API.
2023-08-07 15:02:14 +00:00
Charlie Marsh bae87fa016
Rename semantic model methods to use `current_*` prefix (#6347)
## Summary

This PR attempts to draw a clearer divide between "methods that take
(e.g.) an expression or statement as input" and "methods that rely on
the _current_ expression or statement" in the semantic model, by
renaming methods like `stmt()` to `current_statement()`.

This had led to confusion in the past. For example, prior to this PR, we
had `scope()` (which returns the current scope), and `parent_scope`,
which returns the parent _of a scope that's passed in_. Now, the API is
clearer: `current_scope` returns the current scope, and `parent_scope`
takes a scope as argument and returns its parent.

Per above, I also changed `stmt` to `statement` and `expr` to
`expression`.
2023-08-07 14:44:49 +00:00
Charlie Marsh 76148ddb76
Store call paths rather than stringified names (#6102)
## Summary

Historically, we've stored "qualified names" on our
`BindingKind::Import`, `BindingKind::SubmoduleImport`, and
`BindingKind::ImportFrom` structs. In Ruff, a "qualified name" is a
dot-separated path to a symbol. For example, given `import foo.bar`, the
"qualified name" would be `"foo.bar"`; and given `from foo.bar import
baz`, the "qualified name" would be `foo.bar.baz`.

This PR modifies the `BindingKind` structs to instead store _call paths_
rather than qualified names. So in the examples above, we'd store
`["foo", "bar"]` and `["foo", "bar", "baz"]`. It turns out that this
more efficient given our data access patterns. Namely, we frequently
need to convert the qualified name to a call path (whenever we call
`resolve_call_path`), and it turns out that we do this operation enough
that those conversations show up on benchmarks.

There are a few other advantages to using call paths, rather than
qualified names:

1. The size of `BindingKind` is reduced from 32 to 24 bytes, since we no
longer need to store a `String` (only a boxed slice).
2. All three import types are more consistent, since they now all store
a boxed slice, rather than some storing an `&str` and some storing a
`String` (for `BindingKind::ImportFrom`, we needed to allocate a
`String` to create the qualified name, but the call path is a slice of
static elements that don't require that allocation).
3. A lot of code gets simpler, in part because we now do call path
resolution "earlier". Most notably, for relative imports (`from .foo
import bar`), we store the _resolved_ call path rather than the relative
call path, so the semantic model doesn't have to deal with that
resolution. (See that `resolve_call_path` is simpler, fewer branches,
etc.)

In my testing, this change improves the all-rules benchmark by another
4-5% on top of the improvements mentioned in #6047.
2023-08-05 15:21:50 +00:00
Zanie Blue 047c211837
Add semantic analysis of type aliases and parameters (#6109)
Requires https://github.com/astral-sh/RustPython-Parser/pull/42
Related https://github.com/PyCQA/pyflakes/pull/778
[PEP-695](https://peps.python.org/pep-0695)
Part of #5062 

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## Summary

<!-- What's the purpose of the change? What does it do, and why? -->
Adds a scope for type parameters, a type parameter binding kind, and
checker visitation of type parameters in type alias statements, function
definitions, and class definitions.

A few changes were necessary to ensure correctness following the
insertion of a new scope between function and class scopes and their
parent.

## Test Plan

<!-- How was it tested? -->
Undefined name snapshots.

Unused type parameter rule will be added as follow-up.
2023-07-28 17:06:37 -05:00
Charlie Marsh 0bc3edf6c9
Add documentation and test cases for redefinition (#6135) 2023-07-28 00:01:42 +00:00
Micha Reiser 40f54375cb
Pull in RustPython parser (#6099) 2023-07-27 09:29:11 +00:00
Victor Hugo Gomes 86539c1fc5
[`flake8-pyi`] Implement `PYI046` (#6098)
## Summary
Checks for the presence of unused private `typing.Protocol` definitions.

ref #848 

## Test Plan

Snapshots and manual runs of flake8.
2023-07-27 02:34:56 +00:00
Victor Hugo Gomes c0dbcb3434
[`flake8-pyi`] Implement PYI018 (#6018)
## Summary

Check for unused private `TypeVar`. See [original
implementation](2a86db8271/pyi.py (L1958)).

```
$ flake8 --select Y018 crates/ruff/resources/test/fixtures/flake8_pyi/PYI018.pyi

crates/ruff/resources/test/fixtures/flake8_pyi/PYI018.pyi:4:1: Y018 TypeVar "_T" is not used
crates/ruff/resources/test/fixtures/flake8_pyi/PYI018.pyi:5:1: Y018 TypeVar "_P" is not used
```

```
$ ./target/debug/ruff --select PYI018 crates/ruff/resources/test/fixtures/flake8_pyi/PYI018.pyi --no-cache

crates/ruff/resources/test/fixtures/flake8_pyi/PYI018.pyi:4:1: PYI018 TypeVar `_T` is never used
crates/ruff/resources/test/fixtures/flake8_pyi/PYI018.pyi:5:1: PYI018 TypeVar `_P` is never used
Found 2 errors.
```
In the file `unused_private_type_declaration.rs`, I'm planning to add
other rules that are similar to `PYI018` like the `PYI046`, `PYI047` and
`PYI049`.

ref #848

## Test Plan

Snapshots and manual runs of flake8.
2023-07-26 22:56:15 +00:00
Micha Reiser 2cf00fee96
Remove parser dependency from ruff-python-ast (#6096) 2023-07-26 17:47:22 +02:00
Charlie Marsh ed72c027a3
Replace `NoHashHasher` usages with `FxHashMap` (#6049)
## Summary

I had always assumed that `NoHashHasher` would be faster when using
integer keys, but benchmarking shows otherwise:

```
linter/default-rules/numpy/globals.py
                        time:   [66.544 µs 66.606 µs 66.678 µs]
                        thrpt:  [44.253 MiB/s 44.300 MiB/s 44.342 MiB/s]
                 change:
                        time:   [-0.1843% +0.1087% +0.3718%] (p = 0.46 > 0.05)
                        thrpt:  [-0.3704% -0.1086% +0.1847%]
                        No change in performance detected.
Found 1 outliers among 100 measurements (1.00%)
  1 (1.00%) high mild
linter/default-rules/pydantic/types.py
                        time:   [1.3787 ms 1.3811 ms 1.3837 ms]
                        thrpt:  [18.431 MiB/s 18.466 MiB/s 18.498 MiB/s]
                 change:
                        time:   [-0.4827% -0.1074% +0.1927%] (p = 0.56 > 0.05)
                        thrpt:  [-0.1924% +0.1075% +0.4850%]
                        No change in performance detected.
linter/default-rules/numpy/ctypeslib.py
                        time:   [624.82 µs 625.96 µs 627.17 µs]
                        thrpt:  [26.550 MiB/s 26.601 MiB/s 26.650 MiB/s]
                 change:
                        time:   [-0.7071% -0.4908% -0.2736%] (p = 0.00 < 0.05)
                        thrpt:  [+0.2744% +0.4932% +0.7122%]
                        Change within noise threshold.
linter/default-rules/large/dataset.py
                        time:   [3.1585 ms 3.1634 ms 3.1685 ms]
                        thrpt:  [12.840 MiB/s 12.861 MiB/s 12.880 MiB/s]
                 change:
                        time:   [-1.5338% -1.3463% -1.1476%] (p = 0.00 < 0.05)
                        thrpt:  [+1.1610% +1.3647% +1.5577%]
                        Performance has improved.

linter/all-rules/numpy/globals.py
                        time:   [140.17 µs 140.37 µs 140.58 µs]
                        thrpt:  [20.989 MiB/s 21.020 MiB/s 21.051 MiB/s]
                 change:
                        time:   [-0.1066% +0.3140% +0.7479%] (p = 0.14 > 0.05)
                        thrpt:  [-0.7423% -0.3130% +0.1067%]
                        No change in performance detected.
Found 3 outliers among 100 measurements (3.00%)
  2 (2.00%) high mild
  1 (1.00%) high severe
linter/all-rules/pydantic/types.py
                        time:   [2.7030 ms 2.7069 ms 2.7112 ms]
                        thrpt:  [9.4064 MiB/s 9.4216 MiB/s 9.4351 MiB/s]
                 change:
                        time:   [-0.6721% -0.4874% -0.2974%] (p = 0.00 < 0.05)
                        thrpt:  [+0.2982% +0.4898% +0.6766%]
                        Change within noise threshold.
Found 14 outliers among 100 measurements (14.00%)
  12 (12.00%) high mild
  2 (2.00%) high severe
linter/all-rules/numpy/ctypeslib.py
                        time:   [1.4709 ms 1.4727 ms 1.4749 ms]
                        thrpt:  [11.290 MiB/s 11.306 MiB/s 11.320 MiB/s]
                 change:
                        time:   [-1.1617% -0.9766% -0.8094%] (p = 0.00 < 0.05)
                        thrpt:  [+0.8160% +0.9862% +1.1754%]
                        Change within noise threshold.
Found 12 outliers among 100 measurements (12.00%)
  9 (9.00%) high mild
  3 (3.00%) high severe
linter/all-rules/large/dataset.py
                        time:   [5.8086 ms 5.8163 ms 5.8240 ms]
                        thrpt:  [6.9854 MiB/s 6.9946 MiB/s 7.0038 MiB/s]
                 change:
                        time:   [-1.5651% -1.3536% -1.1584%] (p = 0.00 < 0.05)
                        thrpt:  [+1.1720% +1.3721% +1.5900%]
                        Performance has improved.
```

My guess is that `NoHashHasher` underperforms because the keys are not
randomly distributed...

Anyway, it's a ~1% (significant) performance gain on some of the above,
plus we get to remove a dependency.
2023-07-24 23:41:57 +00:00
Charlie Marsh 057faabcdd
Use `Flags::intersects` rather than `Flags::contains` (#6007)
## Summary

This is equivalent for a single flag, but I think it's more likely to be
correct when the bitflags are modified -- the primary reason being that
we sometimes define flags as the union of other flags, e.g.:

```rust
const ANNOTATION = Self::TYPING_ONLY_ANNOTATION.bits() | Self::RUNTIME_ANNOTATION.bits();
```

In this case, `flags.contains(Flag::ANNOTATION)` requires that _both_
flags in the union are set, whereas `flags.intersects(Flag::ANNOTATION)`
requires that _at least one_ flag is set.
2023-07-23 02:59:31 +00:00
Charlie Marsh 963f240e46
Track unresolved references in the semantic model (#5902)
## Summary

As part of my continued quest to separate semantic model-building from
diagnostic emission, this PR moves our unresolved-reference rules to a
deferred pass. So, rather than emitting diagnostics as we encounter
unresolved references, we now track those unresolved references on the
semantic model (just like resolved references), and after traversal,
emit the relevant rules for any unresolved references.
2023-07-19 18:19:55 -04:00
Charlie Marsh 9834c69c98
Remove `__all__` enforcement rules out of binding phase (#5897)
## Summary

This PR moves two rules (`invalid-all-format` and `invalid-all-object`)
out of the name-binding phase, and into the dedicated pass over all
bindings that occurs at the end of the `Checker`. This is part of my
continued quest to separate the semantic model-building logic from the
actual rule enforcement.
2023-07-19 21:18:47 +00:00
Charlie Marsh a75a6de577
Use a boxed slice for `Export` struct (#5887)
## Summary

The vector of names here is immutable -- we never push to it after
initialization. Boxing reduces the size of the variant from 32 bytes to
24 bytes. (See:
https://nnethercote.github.io/perf-book/type-sizes.html#boxed-slices.)
It doesn't make a difference here, since it's not the largest variant,
but it still seems like a prudent change (and I was considering adding
another field to this variant, though I may no longer do so).
2023-07-19 11:45:04 -04:00
Charlie Marsh 1181d25e5a
Move a few more candidate rules to the deferred `Binding`-only pass (#5853)
## Summary

No behavior change, but this is in theory more efficient, since we can
just iterate over the flat `Binding` vector rather than having to
iterate over binding chains via the `Scope`.
2023-07-19 00:59:02 +00:00
Charlie Marsh 7ffcd93afd
Move unused deletion tracking to deferred analysis (#5852)
## Summary

This PR moves the "unused exception" rule out of the visitor and into a
deferred check. When we can base rules solely on the semantic model, we
probably should, as it greatly simplifies the `Checker` itself.
2023-07-18 20:43:12 -04:00
Charlie Marsh 9e1039f823
Enable attribute lookups via semantic model (#5536)
## Summary

This PR enables us to resolve attribute accesses within files, at least
for static and class methods. For example, we can now detect that this
is a function access (and avoid a false-positive):

```python
class Class:
    @staticmethod
    def error():
        return ValueError("Something")


# OK
raise Class.error()
```

Closes #5487.

Closes #5416.
2023-07-05 15:19:14 -04:00
Charlie Marsh ecf61d49fa
Restore existing bindings when unbinding caught exceptions (#5256)
## Summary

In the latest release, we made some improvements to the semantic model,
but our modifications to exception-unbinding are causing some
false-positives. For example:

```py
try:
    v = 3
except ImportError as v:
    print(v)
else:
    print(v)
```

In the latest release, we started unbinding `v` after the `except`
handler. (We used to restore the existing binding, the `v = 3`, but this
was quite complicated.) Because we don't have full branch analysis, we
can't then know that `v` is still bound in the `else` branch.

The solution here modifies `resolve_read` to skip-lookup when hitting
unbound exceptions. So when store the "unbind" for `except ImportError
as v`, we save the binding that it shadowed `v = 3`, and skip to that.

Closes #5249.

Closes #5250.
2023-06-21 12:53:58 -04:00
Charlie Marsh 310abc769d
Move `StarImport` to its own module (#5186) 2023-06-20 13:12:46 -04:00
Charlie Marsh 94abf7f088
Rename `*Importation` structs to `*Import` (#5185)
## Summary

I find "Importation" a bit awkward, it may not even be grammatically
correct here.
2023-06-19 12:09:10 -04:00