ruff/crates
David Peter dac4e356eb
[ty] Use all reachable bindings for instance attributes and deferred lookups (#18955)
## Summary

Remove a hack in control flow modeling that was treating `return`
statements at the end of function bodies in a special way (basically
considering the state *just before* the `return` statement as the
end-of-scope state). This is not needed anymore now that #18750 has been
merged.

In order to make this work, we now use *all reachable bindings* for
purposes of finding implicit instance attribute assignments as well as
for deferred lookups of symbols. Both would otherwise be affected by
this change:
```py
def C:
    def f(self):
        self.x = 1  # a reachable binding that is not visible at the end of the scope
        return
```

```py
def f():
    class X: ...  # a reachable binding that is not visible at the end of the scope
    x: "X" = X()  # deferred use of `X`
    return
```

Implicit instance attributes also required another change. We previously
kept track of possibly-unbound instance attributes in some cases, but we
now give up on that completely and always consider *implicit* instance
attributes to be bound if we see a reachable binding in a reachable
method. The previous behavior was somewhat inconsistent anyway because
we also do not consider attributes possibly-unbound in other scenarios:
we do not (and can not) keep track of whether or not methods are called
that define these attributes.

closes https://github.com/astral-sh/ty/issues/711

## Ecosystem analysis

I think this looks very positive!

* We see an unsurprising drop in `possibly-unbound-attribute`
diagnostics (599), mostly for classes that define attributes in `try …
except` blocks, `for` loops, or `if … else: raise …` constructs. There
might obviously also be true positives that got removed, but the vast
majority should be false positives.
* There is also a drop in `possibly-unresolved-reference` /
`unresolved-reference` diagnostics (279+13) from the change to deferred
lookups.
* Some `invalid-type-form` false positives got resolved (13), because we
can now properly look up the names in the annotations.
* There are some new *true* positives in `attrs`, since we understand
the `Attribute` annotation that was previously inferred as `Unknown`
because of a re-assignment after the class definition.


## Test Plan

The existing attributes.md test suite has sufficient coverage here.
2025-07-01 14:38:36 +02:00
..
ruff Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_annotate_snippets Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_benchmark [ty] Reduce 'complex_constrained_attributes_2' runtime (#19001) 2025-06-27 23:15:45 +02:00
ruff_cache Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
ruff_db Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_dev Remove `Message::to_rule` (#18447) 2025-06-05 12:48:29 -04:00
ruff_diagnostics Add a `ViolationMetadata::rule` method (#18234) 2025-05-28 09:27:09 -04:00
ruff_formatter Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
ruff_graph Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_index Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_linter [`flake8-pyi`] Make `PYI032` example error out-of-the-box (#19061) 2025-07-01 07:50:58 +01:00
ruff_macros Apply fix availability and applicability when adding to `DiagnosticGuard` and remove `NoqaCode::rule` (#18834) 2025-06-24 10:08:36 -04:00
ruff_notebook Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
ruff_options_metadata [ty] Document configuration schema (#17950) 2025-05-09 10:47:45 +02:00
ruff_python_ast Make dependency `get-size2` truly optional in `ruff_python_ast` (#19052) 2025-06-30 21:50:59 -05:00
ruff_python_ast_integration_tests [ty] AST garbage collection (#18482) 2025-06-13 08:40:11 -04:00
ruff_python_codegen Fix f-string interpolation escaping (#18882) 2025-06-25 10:04:15 +02:00
ruff_python_formatter Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_python_index Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
ruff_python_literal Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
ruff_python_parser [ty] Add environment variable to dump Salsa memory usage stats (#18928) 2025-06-26 21:27:51 +00:00
ruff_python_semantic [`flake8-pyi`] Expand `Optional[A]` to `A | None` (`PYI016`) (#18572) 2025-06-27 15:43:11 +00:00
ruff_python_stdlib Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
ruff_python_trivia Treat `ty: ` comments as pragma comments (#18532) 2025-06-07 16:02:43 +02:00
ruff_python_trivia_integration_tests Switch to Rust 2024 edition (#18129) 2025-05-16 13:25:28 +02:00
ruff_server Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_source_file [ty] Add environment variable to dump Salsa memory usage stats (#18928) 2025-06-26 21:27:51 +00:00
ruff_text_size [ty] Add environment variable to dump Salsa memory usage stats (#18928) 2025-06-26 21:27:51 +00:00
ruff_wasm Convert `OldDiagnostic::noqa_code` to an `Option<String>` (#18946) 2025-06-27 11:36:55 -04:00
ruff_workspace Apply fix availability and applicability when adding to `DiagnosticGuard` and remove `NoqaCode::rule` (#18834) 2025-06-24 10:08:36 -04:00
ty [ty] Print salsa memory usage totals in mypy primer CI runs (#18973) 2025-06-28 15:09:50 -04:00
ty_ide Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ty_project [ty] Print salsa memory usage totals in mypy primer CI runs (#18973) 2025-06-28 15:09:50 -04:00
ty_python_semantic [ty] Use all reachable bindings for instance attributes and deferred lookups (#18955) 2025-07-01 14:38:36 +02:00
ty_server Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ty_test Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ty_vendored [ty] Sync vendored typeshed stubs (#19060) 2025-07-01 07:45:06 +01:00
ty_wasm Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00