The diagnostic now includes a pointer to the implementation definition
along with each possible overload.
This doesn't include information about *why* each overload failed. But
given the emphasis on concise output (since there can be *many*
unmatched overloads), it's not totally clear how to include that
additional information.
Fixes#274
These are, after all, specific to function types. The methods on `Type`
are more like conveniences that return something when the type *happens*
to be a function. But defining them on `FunctionType` itself makes it
easy to call them when you have a `FunctionType` instead of a `Type`.
I found the previous code somewhat harder to read. Namely, a `for`
loop was being used to encode "execute zero or one times, but not
more." Which is sometimes okay, but it seemed clearer to me to use
more explicit case analysis here.
This should have no behavioral changes.
## Summary
Dunder methods are never looked up on instances. We do this implicitly
in `try_call_dunder`, but the corresponding flag was missing in the
instance-construction code where we use `member_lookup_with_policy`
directly.
fixes https://github.com/astral-sh/ty/issues/322
## Test Plan
Added regression test.
## Summary
This PR adds cycle handling for `infer_unpack_types` based on the
analysis in astral-sh/ty#364.
Fixes: astral-sh/ty#364
## Test Plan
Add a cycle handling test for unpacking in `cycle.md`
Follows on from (and depends on)
https://github.com/astral-sh/ruff/pull/18021.
This updates our function specialization inference to infer type
mappings from parameters that are generic protocols.
For now, this only works when the argument _explicitly_ implements the
protocol by listing it as a base class. (We end up using exactly the
same logic as for generic classes in #18021.) For this to work with
classes that _implicitly_ implement the protocol, we will have to check
the types of the protocol members (which we are not currently doing), so
that we can infer the specialization of the protocol that the class
implements.
---------
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
## Summary
Understand that `__file__` is always set and a `str` when looked up as
an implicit global from a Python file we are type checking.
## Test Plan
mdtests
## Summary
Fix the lookup of `submodule`s in cases where the `parent` module has a
self-referential import like `from parent import submodule`. This allows
us to infer proper types for many symbols where we previously inferred
`Never`. This leads to many new false (and true) positives across the
ecosystem because the fact that we previously inferred `Never` shadowed
a lot of problems. For example, we inferred `Never` for `os.path`, which
is why we now see a lot of new diagnostics related to `os.path.abspath`
and similar.
```py
import os
reveal_type(os.path) # previously: Never, now: <module 'os.path'>
```
closes https://github.com/astral-sh/ty/issues/261
closes https://github.com/astral-sh/ty/issues/307
## Ecosystem analysis
```
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━┳━━━━━━━━━┳━━━━━━━┳━━━━━━━━━━━━┓
┃ Diagnostic ID ┃ Severity ┃ Removed ┃ Added ┃ Net Change ┃
┡━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━╇━━━━━━━━━╇━━━━━━━╇━━━━━━━━━━━━┩
│ call-non-callable │ error │ 1 │ 5 │ +4 │
│ call-possibly-unbound-method │ warning │ 6 │ 26 │ +20 │
│ invalid-argument-type │ error │ 26 │ 94 │ +68 │
│ invalid-assignment │ error │ 18 │ 46 │ +28 │
│ invalid-context-manager │ error │ 9 │ 4 │ -5 │
│ invalid-raise │ error │ 1 │ 1 │ 0 │
│ invalid-return-type │ error │ 3 │ 20 │ +17 │
│ invalid-super-argument │ error │ 4 │ 0 │ -4 │
│ invalid-type-form │ error │ 573 │ 0 │ -573 │
│ missing-argument │ error │ 2 │ 10 │ +8 │
│ no-matching-overload │ error │ 0 │ 715 │ +715 │
│ non-subscriptable │ error │ 0 │ 35 │ +35 │
│ not-iterable │ error │ 6 │ 7 │ +1 │
│ possibly-unbound-attribute │ warning │ 14 │ 31 │ +17 │
│ possibly-unbound-import │ warning │ 13 │ 0 │ -13 │
│ possibly-unresolved-reference │ warning │ 0 │ 8 │ +8 │
│ redundant-cast │ warning │ 1 │ 0 │ -1 │
│ too-many-positional-arguments │ error │ 2 │ 0 │ -2 │
│ unknown-argument │ error │ 2 │ 0 │ -2 │
│ unresolved-attribute │ error │ 583 │ 304 │ -279 │
│ unresolved-import │ error │ 0 │ 96 │ +96 │
│ unsupported-operator │ error │ 0 │ 17 │ +17 │
│ unused-ignore-comment │ warning │ 29 │ 2 │ -27 │
├───────────────────────────────┼──────────┼─────────┼───────┼────────────┤
│ TOTAL │ │ 1293 │ 1421 │ +128 │
└───────────────────────────────┴──────────┴─────────┴───────┴────────────┘
Analysis complete. Found 23 unique diagnostic IDs.
Total diagnostics removed: 1293
Total diagnostics added: 1421
Net change: +128
```
* We see a lot of new errors (`no-matching-overload`) related to
`os.path.dirname` and other `os.path` operations because we infer `str |
None` for `__file__`, but many projects use something like
`os.path.dirname(__file__)`.
* We also see many new `unresolved-attribute` errors related to the fact
that we now infer proper module types for some imports (e.g. `import
kornia.augmentation as K`), but we don't allow implicit imports (e.g.
accessing `K.auto.operations` without also importing `K.auto`). See
https://github.com/astral-sh/ty/issues/133.
* Many false positive `invalid-type-form` are removed because we now
infer the correct type for some type expression instead of `Never`,
which is not valid in a type annotation/expression context.
## Test Plan
Added new Markdown tests
## Summary
If the user tries to use a new builtin on an old Python version, tell
them what Python version the builtin was added on, what our inferred
Python version is for their project, and what configuration settings
they can tweak to fix the error.
## Test Plan
Snapshots and screenshots:
Fixes: https://github.com/astral-sh/ty/issues/92
## Summary
We currently get a `invalid-argument-type` error when using
`dataclass.fields` on a dataclass, because we do not synthesize the
`__dataclass_fields__` member.
This PR fixes this diagnostic.
Note that we do not yet model the `Field` type correctly. After that is
done, we can assign a more precise `tuple[Field, ...]` type to this new
member.
## Test Plan
New mdtest.
---------
Co-authored-by: David Peter <mail@david-peter.de>
This updates our function specialization inference to infer type
mappings from parameters that are generic aliases, e.g.:
```py
def f[T](x: list[T]) -> T: ...
reveal_type(f(["a", "b"])) # revealed: str
```
Though note that we're still inferring the type of list literals as
`list[Unknown]`, so for now we actually need something like the
following in our tests:
```py
def _(x: list[str]):
reveal_type(f(x)) # revealed: str
```
We were not inducting into instance types and subclass-of types when
looking for legacy typevars, nor when apply specializations.
This addresses
https://github.com/astral-sh/ruff/pull/17832#discussion_r2081502056
```py
from __future__ import annotations
from typing import TypeVar, Any, reveal_type
S = TypeVar("S")
class Foo[T]:
def method(self, other: Foo[S]) -> Foo[T | S]: ... # type: ignore[invalid-return-type]
def f(x: Foo[Any], y: Foo[Any]):
reveal_type(x.method(y)) # revealed: `Foo[Any | S]`, but should be `Foo[Any]`
```
We were not detecting that `S` made `method` generic, since we were not
finding it when searching the function signature for legacy typevars.
## Summary
Updates the `--python` flag to accept Python executables in virtual
environments. Notably, we do not query the executable and it _must_ be
in a canonical location in a virtual environment. This is pretty naive,
but solves for the trivial case of `ty check --python .venv/bin/python3`
which will be a common mistake (and `ty check --python $(which python)`)
I explored this while trying to understand Python discovery in ty in
service of https://github.com/astral-sh/ty/issues/272, I'm not attached
to it, but figure it's worth sharing.
As an alternative, we can add more variants to the
`SearchPathValidationError` and just improve the _error_ message, i.e.,
by hinting that this looks like a virtual environment and suggesting the
concrete alternative path they should provide. We'll probably want to do
that for some other cases anyway (e.g., `3.13` as described in the
linked issue)
This functionality is also briefly mentioned in
https://github.com/astral-sh/ty/issues/193
Closes https://github.com/astral-sh/ty/issues/318
## Test Plan
e.g.,
```
uv run ty check --python .venv/bin/python3
```
needs test coverage still
Function literals have an optional specialization, which is applied to
the parameter/return type annotations lazily when the function's
signature is requested. We were previously only applying this
specialization to the final overload of an overloaded function.
This manifested most visibly for `list.__add__`, which has an overloaded
definition in the typeshed:
b398b83631/crates/ty_vendored/vendor/typeshed/stdlib/builtins.pyi (L1069-L1072)
Closes https://github.com/astral-sh/ty/issues/314
## Summary
I found this bug while working on #18041. The following code leads to
infinite recursion.
```python
from ty_extensions import is_disjoint_from, static_assert, TypeOf
class C:
@property
def prop(self) -> int:
return 1
static_assert(not is_disjoint_from(int, TypeOf[C.prop]))
```
The cause is a trivial missing binding in `is_disjoint_from`. This PR
fixes the bug and adds a test case (this is a simple fix and may not
require a new test case?).
## Test Plan
A new test case is added to
`mdtest/type_properties/is_disjoint_from.md`.
## Summary
`KnownClass::Range`, `KnownInstanceType::Any` and `ClassBase::any()` are
no longer used or useful: all our tests pass with them removed.
`KnownModule::Abc` _is_ now used outside of tests, however, so I removed
the `#[allow(dead_code)]` branch above that variant.
## Test Plan
`cargo test -p ty_python_semantic`
Follow-up to https://github.com/astral-sh/ruff/pull/17991 ensuring we do
not allow detection of system environments when the origin is
`VIRTUAL_ENV` or a discovered `.venv` directory — i.e., those always
require a `pyvenv.cfg` file.
Adds test coverage for https://github.com/astral-sh/ruff/pull/17991,
which includes some minor refactoring of the virtual environment test
infrastructure.
I tried to minimize stylistic changes, but there are still a few because
I was a little confused by the setup. I could see this evolving more in
the future, as I don't think the existing model can capture all the test
coverage I'm looking for.
This adds basic support for non-virtual Python environments by accepting
a directory without a `pyvenv.cfg` which allows existing, subsequent
site-packages discovery logic to succeed. We can do better here in the
long-term, by adding more eager validation (for error messages) and
parsing the Python version from the discovered site-packages directory
(which isn't relevant yet, because we don't use the discovered Python
version from virtual environments as the default `--python-version` yet
either).
Related
- https://github.com/astral-sh/ty/issues/265
- https://github.com/astral-sh/ty/issues/193
You can review this commit by commit if it makes you happy.
I tested this manually; I think refactoring the test setup is going to
be a bit more invasive so I'll stack it on top (see
https://github.com/astral-sh/ruff/pull/17996).
```
❯ uv run ty check --python /Users/zb/.local/share/uv/python/cpython-3.10.17-macos-aarch64-none/ -vv example
2025-05-09 12:06:33.685911 DEBUG Version: 0.0.0-alpha.7 (f9c4c8999 2025-05-08)
2025-05-09 12:06:33.685987 DEBUG Architecture: aarch64, OS: macos, case-sensitive: case-insensitive
2025-05-09 12:06:33.686002 DEBUG Searching for a project in '/Users/zb/workspace/ty'
2025-05-09 12:06:33.686123 DEBUG Resolving requires-python constraint: `>=3.8`
2025-05-09 12:06:33.686129 DEBUG Resolved requires-python constraint to: 3.8
2025-05-09 12:06:33.686142 DEBUG Project without `tool.ty` section: '/Users/zb/workspace/ty'
2025-05-09 12:06:33.686147 DEBUG Searching for a user-level configuration at `/Users/zb/.config/ty/ty.toml`
2025-05-09 12:06:33.686156 INFO Defaulting to python-platform `darwin`
2025-05-09 12:06:33.68636 INFO Python version: Python 3.8, platform: darwin
2025-05-09 12:06:33.686375 DEBUG Adding first-party search path '/Users/zb/workspace/ty'
2025-05-09 12:06:33.68638 DEBUG Using vendored stdlib
2025-05-09 12:06:33.686634 DEBUG Discovering site-packages paths from sys-prefix `/Users/zb/.local/share/uv/python/cpython-3.10.17-macos-aarch64-none` (`--python` argument')
2025-05-09 12:06:33.686667 DEBUG Attempting to parse virtual environment metadata at '/Users/zb/.local/share/uv/python/cpython-3.10.17-macos-aarch64-none/pyvenv.cfg'
2025-05-09 12:06:33.686671 DEBUG Searching for site-packages directory in `sys.prefix` path `/Users/zb/.local/share/uv/python/cpython-3.10.17-macos-aarch64-none`
2025-05-09 12:06:33.686702 DEBUG Resolved site-packages directories for this environment are: ["/Users/zb/.local/share/uv/python/cpython-3.10.17-macos-aarch64-none/lib/python3.10/site-packages"]
2025-05-09 12:06:33.686706 DEBUG Adding site-packages search path '/Users/zb/.local/share/uv/python/cpython-3.10.17-macos-aarch64-none/lib/python3.10/site-packages'
...
❯ uv run ty check --python /tmp -vv example
2025-05-09 15:36:10.819416 DEBUG Version: 0.0.0-alpha.7 (f9c4c8999 2025-05-08)
2025-05-09 15:36:10.819708 DEBUG Architecture: aarch64, OS: macos, case-sensitive: case-insensitive
2025-05-09 15:36:10.820118 DEBUG Searching for a project in '/Users/zb/workspace/ty'
2025-05-09 15:36:10.821652 DEBUG Resolving requires-python constraint: `>=3.8`
2025-05-09 15:36:10.821667 DEBUG Resolved requires-python constraint to: 3.8
2025-05-09 15:36:10.8217 DEBUG Project without `tool.ty` section: '/Users/zb/workspace/ty'
2025-05-09 15:36:10.821888 DEBUG Searching for a user-level configuration at `/Users/zb/.config/ty/ty.toml`
2025-05-09 15:36:10.822072 INFO Defaulting to python-platform `darwin`
2025-05-09 15:36:10.822439 INFO Python version: Python 3.8, platform: darwin
2025-05-09 15:36:10.822773 DEBUG Adding first-party search path '/Users/zb/workspace/ty'
2025-05-09 15:36:10.822929 DEBUG Using vendored stdlib
2025-05-09 15:36:10.829872 DEBUG Discovering site-packages paths from sys-prefix `/tmp` (`--python` argument')
2025-05-09 15:36:10.829911 DEBUG Attempting to parse virtual environment metadata at '/private/tmp/pyvenv.cfg'
2025-05-09 15:36:10.829917 DEBUG Searching for site-packages directory in `sys.prefix` path `/private/tmp`
ty failed
Cause: Invalid search path settings
Cause: Failed to discover the site-packages directory: Failed to search the `lib` directory of the Python installation at `sys.prefix` path `/private/tmp` for `site-packages`
```
## Summary
Suppress false positives for uses of PEP-695 `ParamSpec` in `Callable`
annotations:
```py
from typing_extensions import Callable
def f[**P](c: Callable[P, int]):
pass
```
addresses a comment here:
https://github.com/astral-sh/ty/issues/157#issuecomment-2859284721
## Test Plan
Adapted Markdown tests
Re: #17526
## Summary
Add integration test for semantic syntax for `IrrefutableCasePattern`,
`SingleStarredAssignment`, `WriteToDebug`, and `InvalidExpression`.
## Notes
- Following @ntBre's suggestion, I will keep the test coming in batches
like this over the next few days in separate PRs to keep the review load
per PR manageable while also not spamming too many.
- I did not add a test for `del __debug__` which is one of the examples
in `crates/ruff_python_parser/src/semantic_errors.rs:1051`.
For python version `<= 3.8` there is no error and for `>=3.9` the error
is not `WriteToDebug` but `SyntaxError: cannot delete __debug__ on
Python 3.9 (syntax was removed in 3.9)`.
- The `blacken-docs` bypass is necessary because otherwise the test does
not pass pre-commit checks; but we want to check for this faulty syntax.
<!-- What's the purpose of the change? What does it do, and why? -->
## Test Plan
This is a test.
This makes one very simple change: we report all call binding
errors from each union variant.
This does result in duplicate-seeming diagnostics. For example,
when two union variants are invalid for the same reason.
This does a deeper removal of the `lint:` prefix by removing the
`DiagnosticId::as_str` method and replacing it with `as_concise_str`. We
remove the associated error type and simplify the `Display` impl for
`DiagnosticId` as well.
This turned out to catch a `lint:` that was still in the diagnostic
output: the part that says why a lint is enabled.
We just set the ID on the `Message` and it just does what we want in
this case. I think I didn't do this originally because I was trying to
preserve the existing rendering? I'm not sure. I might have just missed
this method.
In a subsequent commit, we're going to start using `annotate-snippets`'s
functionality for diagnostic IDs in the rendering. As part of doing
that, I wanted to remove this special casing of an empty message. I did
that independently to see what, if anything, would change. (The changes
look fine to me. They'll be tweaked again in the next commit along with
a bunch of others.)
## Summary
Use a self-reference "marker" ~~and fixpoint iteration~~ to solve the
stack overflow problems with recursive protocols. This is not pretty and
somewhat tedious, but seems to work fine. Much better than all my
fixpoint-iteration attempts anyway.
closes https://github.com/astral-sh/ty/issues/93
## Test Plan
New Markdown tests.
