diff --git a/crates/ty/docs/rules.md b/crates/ty/docs/rules.md
index 7cc1eb9ef0..ca0fdf429f 100644
--- a/crates/ty/docs/rules.md
+++ b/crates/ty/docs/rules.md
@@ -50,7 +50,7 @@ Calling a non-callable object will raise a `TypeError` at runtime.
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20call-non-callable)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L88)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L90)
## `conflicting-argument-forms`
@@ -81,7 +81,7 @@ f(int) # error
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20conflicting-argument-forms)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L119)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L121)
## `conflicting-declarations`
@@ -111,7 +111,7 @@ a = 1
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20conflicting-declarations)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L145)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L147)
## `conflicting-metaclass`
@@ -142,7 +142,7 @@ class C(A, B): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20conflicting-metaclass)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L170)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L172)
## `cyclic-class-definition`
@@ -173,7 +173,7 @@ class B(A): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20cyclic-class-definition)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L196)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L198)
## `duplicate-base`
@@ -199,7 +199,7 @@ class B(A, A): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20duplicate-base)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L240)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L242)
## `escape-character-in-forward-annotation`
@@ -336,7 +336,7 @@ TypeError: multiple bases have instance lay-out conflict
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20incompatible-slots)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L261)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L263)
## `inconsistent-mro`
@@ -365,7 +365,7 @@ class C(A, B): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20inconsistent-mro)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L347)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L349)
## `index-out-of-bounds`
@@ -390,7 +390,7 @@ t[3] # IndexError: tuple index out of range
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20index-out-of-bounds)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L371)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L373)
## `invalid-argument-type`
@@ -416,7 +416,7 @@ func("foo") # error: [invalid-argument-type]
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-argument-type)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L391)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L393)
## `invalid-assignment`
@@ -443,7 +443,7 @@ a: int = ''
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-assignment)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L431)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L433)
## `invalid-attribute-access`
@@ -476,7 +476,7 @@ C.instance_var = 3 # error: Cannot assign to instance variable
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-attribute-access)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1337)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1381)
## `invalid-base`
@@ -484,13 +484,22 @@ C.instance_var = 3 # error: Cannot assign to instance variable
**Default level**: error
-detects invalid bases in class definitions
+detects class bases that will cause the class definition to raise an exception at runtime
-TODO #14889
+### What it does
+Checks for class definitions that have bases which are not instances of `type`.
+
+### Why is this bad?
+Class definitions with bases like this will lead to `TypeError` being raised at runtime.
+
+### Examples
+```python
+class A(42): ... # error: [invalid-base]
+```
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-base)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L453)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L455)
## `invalid-context-manager`
@@ -516,7 +525,7 @@ with 1:
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-context-manager)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L462)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L506)
## `invalid-declaration`
@@ -544,7 +553,7 @@ a: str
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-declaration)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L483)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L527)
## `invalid-exception-caught`
@@ -585,7 +594,7 @@ except ZeroDivisionError:
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-exception-caught)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L506)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L550)
## `invalid-generic-class`
@@ -616,7 +625,7 @@ class C[U](Generic[T]): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-generic-class)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L542)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L586)
## `invalid-legacy-type-variable`
@@ -649,7 +658,7 @@ def f(t: TypeVar("U")): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-legacy-type-variable)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L568)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L612)
## `invalid-metaclass`
@@ -681,7 +690,7 @@ class B(metaclass=f): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-metaclass)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L617)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L661)
## `invalid-overload`
@@ -729,7 +738,7 @@ def foo(x: int) -> int: ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-overload)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L644)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L688)
## `invalid-parameter-default`
@@ -754,7 +763,7 @@ def f(a: int = ''): ...
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-parameter-default)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L687)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L731)
## `invalid-protocol`
@@ -787,7 +796,7 @@ TypeError: Protocols can only inherit from other protocols, got
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-protocol)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L319)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L321)
## `invalid-raise`
@@ -835,7 +844,7 @@ def g():
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-raise)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L707)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L751)
## `invalid-return-type`
@@ -859,7 +868,7 @@ def func() -> int:
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-return-type)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L412)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L414)
## `invalid-super-argument`
@@ -903,7 +912,7 @@ super(B, A) # error: `A` does not satisfy `issubclass(A, B)`
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-super-argument)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L750)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L794)
## `invalid-syntax-in-forward-annotation`
@@ -943,7 +952,7 @@ NewAlias = TypeAliasType(get_name(), int) # error: TypeAliasType name mus
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-alias-type)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L596)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L640)
## `invalid-type-checking-constant`
@@ -972,7 +981,7 @@ TYPE_CHECKING = ''
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-checking-constant)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L789)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L833)
## `invalid-type-form`
@@ -1001,7 +1010,7 @@ b: Annotated[int] # `Annotated` expects at least two arguments
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-form)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L813)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L857)
## `invalid-type-variable-constraints`
@@ -1035,7 +1044,7 @@ T = TypeVar('T', bound=str) # valid bound TypeVar
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-variable-constraints)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L837)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L881)
## `missing-argument`
@@ -1059,7 +1068,7 @@ func() # TypeError: func() missing 1 required positional argument: 'x'
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20missing-argument)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L866)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L910)
## `no-matching-overload`
@@ -1087,7 +1096,7 @@ func("string") # error: [no-matching-overload]
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20no-matching-overload)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L885)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L929)
## `non-subscriptable`
@@ -1110,7 +1119,7 @@ Subscripting an object that does not support it will raise a `TypeError` at runt
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20non-subscriptable)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L908)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L952)
## `not-iterable`
@@ -1135,7 +1144,7 @@ for i in 34: # TypeError: 'int' object is not iterable
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20not-iterable)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L926)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L970)
## `parameter-already-assigned`
@@ -1161,7 +1170,7 @@ f(1, x=2) # Error raised here
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20parameter-already-assigned)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L977)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1021)
## `raw-string-type-annotation`
@@ -1220,7 +1229,7 @@ static_assert(int(2.0 * 3.0) == 6) # error: does not have a statically known tr
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20static-assert-error)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1313)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1357)
## `subclass-of-final-class`
@@ -1248,7 +1257,7 @@ class B(A): ... # Error raised here
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20subclass-of-final-class)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1068)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1112)
## `too-many-positional-arguments`
@@ -1274,7 +1283,7 @@ f("foo") # Error raised here
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20too-many-positional-arguments)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1113)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1157)
## `type-assertion-failure`
@@ -1301,7 +1310,7 @@ def _(x: int):
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20type-assertion-failure)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1091)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1135)
## `unavailable-implicit-super-arguments`
@@ -1345,7 +1354,7 @@ class A:
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unavailable-implicit-super-arguments)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1134)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1178)
## `unknown-argument`
@@ -1371,7 +1380,7 @@ f(x=1, y=2) # Error raised here
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unknown-argument)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1191)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1235)
## `unresolved-attribute`
@@ -1398,7 +1407,7 @@ A().foo # AttributeError: 'A' object has no attribute 'foo'
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unresolved-attribute)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1212)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1256)
## `unresolved-import`
@@ -1422,7 +1431,7 @@ import foo # ModuleNotFoundError: No module named 'foo'
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unresolved-import)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1234)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1278)
## `unresolved-reference`
@@ -1446,7 +1455,7 @@ print(x) # NameError: name 'x' is not defined
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unresolved-reference)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1253)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1297)
## `unsupported-bool-conversion`
@@ -1482,7 +1491,7 @@ b1 < b2 < b1 # exception raised here
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unsupported-bool-conversion)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L946)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L990)
## `unsupported-operator`
@@ -1509,7 +1518,7 @@ A() + A() # TypeError: unsupported operand type(s) for +: 'A' and 'A'
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unsupported-operator)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1272)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1316)
## `zero-stepsize-in-slice`
@@ -1533,7 +1542,7 @@ l[1:10:0] # ValueError: slice step cannot be zero
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20zero-stepsize-in-slice)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1294)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1338)
## `call-possibly-unbound-method`
@@ -1551,7 +1560,7 @@ Calling an unbound method will raise an `AttributeError` at runtime.
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20call-possibly-unbound-method)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L106)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L108)
## `invalid-ignore-comment`
@@ -1607,7 +1616,7 @@ A.c # AttributeError: type object 'A' has no attribute 'c'
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20possibly-unbound-attribute)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L998)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1042)
## `possibly-unbound-import`
@@ -1638,7 +1647,7 @@ from module import a # ImportError: cannot import name 'a' from 'module'
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20possibly-unbound-import)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1020)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1064)
## `redundant-cast`
@@ -1664,7 +1673,7 @@ cast(int, f()) # Redundant
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20redundant-cast)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1365)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1409)
## `undefined-reveal`
@@ -1687,7 +1696,7 @@ reveal_type(1) # NameError: name 'reveal_type' is not defined
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20undefined-reveal)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1173)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1217)
## `unknown-rule`
@@ -1720,6 +1729,44 @@ a = 20 / 0 # ty: ignore[division-by-zero]
* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Fsuppression.rs#L40)
+## `unsupported-base`
+
+**Default level**: warn
+
+
+detects class bases that are unsupported as ty could not feasibly calculate the class's MRO
+
+### What it does
+Checks for class definitions that have bases which are unsupported by ty.
+
+### Why is this bad?
+If a class has a base that is an instance of a complex type such as a union type,
+ty will not be able to resolve the [method resolution order] (MRO) for the class.
+This will lead to an inferior understanding of your codebase and unpredictable
+type-checking behavior.
+
+### Examples
+```python
+import datetime
+
+class A: ...
+class B: ...
+
+if datetime.date.today().weekday() != 6:
+ C = A
+else:
+ C = B
+
+class D(C): ... # error: [unsupported-base]
+```
+
+[method resolution order]: https://docs.python.org/3/glossary.html#term-method-resolution-order
+
+### Links
+* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unsupported-base)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L473)
+
+
## `division-by-zero`
**Default level**: ignore
@@ -1740,7 +1787,7 @@ Dividing by zero raises a `ZeroDivisionError` at runtime.
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20division-by-zero)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L222)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L224)
## `possibly-unresolved-reference`
@@ -1767,7 +1814,7 @@ print(x) # NameError: name 'x' is not defined
### Links
* [Related issues](https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20possibly-unresolved-reference)
-* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1046)
+* [View source](https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1090)
## `unused-ignore-comment`
diff --git a/crates/ty_python_semantic/resources/mdtest/mro.md b/crates/ty_python_semantic/resources/mdtest/mro.md
index 4f6e1c9c72..810e716688 100644
--- a/crates/ty_python_semantic/resources/mdtest/mro.md
+++ b/crates/ty_python_semantic/resources/mdtest/mro.md
@@ -173,7 +173,7 @@ if hasattr(DoesNotExist, "__mro__"):
if not isinstance(DoesNotExist, type):
reveal_type(DoesNotExist) # revealed: Unknown & ~type
- class Foo(DoesNotExist): ... # error: [invalid-base]
+ class Foo(DoesNotExist): ... # error: [unsupported-base]
reveal_type(Foo.__mro__) # revealed: tuple[, Unknown, ]
```
@@ -232,11 +232,15 @@ reveal_type(AA.__mro__) # revealed: tuple[, , Unknown, <
## `__bases__` includes a `Union`
+
+
We don't support union types in a class's bases; a base must resolve to a single `ClassType`. If we
find a union type in a class's bases, we infer the class's `__mro__` as being
`[, Unknown, object]`, the same as for MROs that cause errors at runtime.
```py
+from typing_extensions import reveal_type
+
def returns_bool() -> bool:
return True
@@ -250,7 +254,7 @@ else:
reveal_type(x) # revealed: |
-# error: 11 [invalid-base] "Invalid class base with type ` | ` (all bases must be a class, `Any`, `Unknown` or `Todo`)"
+# error: 11 [unsupported-base] "Unsupported class base with type ` | `"
class Foo(x): ...
reveal_type(Foo.__mro__) # revealed: tuple[, Unknown, ]
@@ -259,8 +263,8 @@ reveal_type(Foo.__mro__) # revealed: tuple[, Unknown, |
reveal_type(y) # revealed: |
-# error: 11 [invalid-base] "Invalid class base with type ` | ` (all bases must be a class, `Any`, `Unknown` or `Todo`)"
-# error: 14 [invalid-base] "Invalid class base with type ` | ` (all bases must be a class, `Any`, `Unknown` or `Todo`)"
+# error: 11 [unsupported-base] "Unsupported class base with type ` | `"
+# error: 14 [unsupported-base] "Unsupported class base with type ` | `"
class Foo(x, y): ...
reveal_type(Foo.__mro__) # revealed: tuple[, Unknown, ]
@@ -321,7 +325,7 @@ if returns_bool():
else:
foo = object
-# error: 21 [invalid-base] "Invalid class base with type ` | ` (all bases must be a class, `Any`, `Unknown` or `Todo`)"
+# error: 21 [unsupported-base] "Unsupported class base with type ` | `"
class PossibleError(foo, X): ...
reveal_type(PossibleError.__mro__) # revealed: tuple[, Unknown, ]
@@ -339,12 +343,47 @@ else:
# revealed: tuple[, , , , ] | tuple[, , , , ]
reveal_type(B.__mro__)
-# error: 12 [invalid-base] "Invalid class base with type ` | ` (all bases must be a class, `Any`, `Unknown` or `Todo`)"
+# error: 12 [unsupported-base] "Unsupported class base with type ` | `"
class Z(A, B): ...
reveal_type(Z.__mro__) # revealed: tuple[, Unknown, ]
```
+## `__bases__` lists that include objects that are not instances of `type`
+
+
+
+```py
+class Foo(2): ... # error: [invalid-base]
+```
+
+A base that is not an instance of `type` but does have an `__mro_entries__` method will not raise an
+exception at runtime, so we issue `unsupported-base` rather than `invalid-base`:
+
+```py
+class Foo:
+ def __mro_entries__(self, bases: tuple[type, ...]) -> tuple[type, ...]:
+ return ()
+
+class Bar(Foo()): ... # error: [unsupported-base]
+```
+
+But for objects that have badly defined `__mro_entries__`, `invalid-base` is emitted rather than
+`unsupported-base`:
+
+```py
+class Bad1:
+ def __mro_entries__(self, bases, extra_arg):
+ return ()
+
+class Bad2:
+ def __mro_entries__(self, bases) -> int:
+ return 42
+
+class BadSub1(Bad1()): ... # error: [invalid-base]
+class BadSub2(Bad2()): ... # error: [invalid-base]
+```
+
## `__bases__` lists with duplicate bases
diff --git a/crates/ty_python_semantic/resources/mdtest/snapshots/mro.md_-_Method_Resolution_Or…_-_`__bases__`_includes…_(d2532518c44112c8).snap b/crates/ty_python_semantic/resources/mdtest/snapshots/mro.md_-_Method_Resolution_Or…_-_`__bases__`_includes…_(d2532518c44112c8).snap
new file mode 100644
index 0000000000..1b60443d4d
--- /dev/null
+++ b/crates/ty_python_semantic/resources/mdtest/snapshots/mro.md_-_Method_Resolution_Or…_-_`__bases__`_includes…_(d2532518c44112c8).snap
@@ -0,0 +1,78 @@
+---
+source: crates/ty_test/src/lib.rs
+expression: snapshot
+---
+---
+mdtest name: mro.md - Method Resolution Order tests - `__bases__` includes a `Union`
+mdtest path: crates/ty_python_semantic/resources/mdtest/mro.md
+---
+
+# Python source files
+
+## mdtest_snippet.py
+
+```
+ 1 | from typing_extensions import reveal_type
+ 2 |
+ 3 | def returns_bool() -> bool:
+ 4 | return True
+ 5 |
+ 6 | class A: ...
+ 7 | class B: ...
+ 8 |
+ 9 | if returns_bool():
+10 | x = A
+11 | else:
+12 | x = B
+13 |
+14 | reveal_type(x) # revealed: |
+15 |
+16 | # error: 11 [unsupported-base] "Unsupported class base with type ` | `"
+17 | class Foo(x): ...
+18 |
+19 | reveal_type(Foo.__mro__) # revealed: tuple[, Unknown, ]
+```
+
+# Diagnostics
+
+```
+info[revealed-type]: Revealed type
+ --> src/mdtest_snippet.py:14:13
+ |
+12 | x = B
+13 |
+14 | reveal_type(x) # revealed: |
+ | ^ ` | `
+15 |
+16 | # error: 11 [unsupported-base] "Unsupported class base with type ` | `"
+ |
+
+```
+
+```
+warning[unsupported-base]: Unsupported class base with type ` | `
+ --> src/mdtest_snippet.py:17:11
+ |
+16 | # error: 11 [unsupported-base] "Unsupported class base with type ` | `"
+17 | class Foo(x): ...
+ | ^
+18 |
+19 | reveal_type(Foo.__mro__) # revealed: tuple[, Unknown, ]
+ |
+info: ty cannot resolve a consistent MRO for class `Foo` due to this base
+info: Only class objects or `Any` are supported as class bases
+info: rule `unsupported-base` is enabled by default
+
+```
+
+```
+info[revealed-type]: Revealed type
+ --> src/mdtest_snippet.py:19:13
+ |
+17 | class Foo(x): ...
+18 |
+19 | reveal_type(Foo.__mro__) # revealed: tuple[, Unknown, ]
+ | ^^^^^^^^^^^ `tuple[, Unknown, ]`
+ |
+
+```
diff --git a/crates/ty_python_semantic/resources/mdtest/snapshots/mro.md_-_Method_Resolution_Or…_-_`__bases__`_lists_th…_(6f8d0bf648c4b305).snap b/crates/ty_python_semantic/resources/mdtest/snapshots/mro.md_-_Method_Resolution_Or…_-_`__bases__`_lists_th…_(6f8d0bf648c4b305).snap
new file mode 100644
index 0000000000..3a7a401bb7
--- /dev/null
+++ b/crates/ty_python_semantic/resources/mdtest/snapshots/mro.md_-_Method_Resolution_Or…_-_`__bases__`_lists_th…_(6f8d0bf648c4b305).snap
@@ -0,0 +1,97 @@
+---
+source: crates/ty_test/src/lib.rs
+expression: snapshot
+---
+---
+mdtest name: mro.md - Method Resolution Order tests - `__bases__` lists that include objects that are not instances of `type`
+mdtest path: crates/ty_python_semantic/resources/mdtest/mro.md
+---
+
+# Python source files
+
+## mdtest_snippet.py
+
+```
+ 1 | class Foo(2): ... # error: [invalid-base]
+ 2 | class Foo:
+ 3 | def __mro_entries__(self, bases: tuple[type, ...]) -> tuple[type, ...]:
+ 4 | return ()
+ 5 |
+ 6 | class Bar(Foo()): ... # error: [unsupported-base]
+ 7 | class Bad1:
+ 8 | def __mro_entries__(self, bases, extra_arg):
+ 9 | return ()
+10 |
+11 | class Bad2:
+12 | def __mro_entries__(self, bases) -> int:
+13 | return 42
+14 |
+15 | class BadSub1(Bad1()): ... # error: [invalid-base]
+16 | class BadSub2(Bad2()): ... # error: [invalid-base]
+```
+
+# Diagnostics
+
+```
+error[invalid-base]: Invalid class base with type `Literal[2]`
+ --> src/mdtest_snippet.py:1:11
+ |
+1 | class Foo(2): ... # error: [invalid-base]
+ | ^
+2 | class Foo:
+3 | def __mro_entries__(self, bases: tuple[type, ...]) -> tuple[type, ...]:
+ |
+info: Definition of class `Foo` will raise `TypeError` at runtime
+info: rule `invalid-base` is enabled by default
+
+```
+
+```
+warning[unsupported-base]: Unsupported class base with type `Foo`
+ --> src/mdtest_snippet.py:6:11
+ |
+4 | return ()
+5 |
+6 | class Bar(Foo()): ... # error: [unsupported-base]
+ | ^^^^^
+7 | class Bad1:
+8 | def __mro_entries__(self, bases, extra_arg):
+ |
+info: ty cannot resolve a consistent MRO for class `Bar` due to this base
+info: Only class objects or `Any` are supported as class bases
+info: rule `unsupported-base` is enabled by default
+
+```
+
+```
+error[invalid-base]: Invalid class base with type `Bad1`
+ --> src/mdtest_snippet.py:15:15
+ |
+13 | return 42
+14 |
+15 | class BadSub1(Bad1()): ... # error: [invalid-base]
+ | ^^^^^^
+16 | class BadSub2(Bad2()): ... # error: [invalid-base]
+ |
+info: Definition of class `BadSub1` will raise `TypeError` at runtime
+info: An instance type is only a valid class base if it has a valid `__mro_entries__` method
+info: Type `Bad1` has an `__mro_entries__` method, but it cannot be called with the expected arguments
+info: Expected a signature at least as permissive as `def __mro_entries__(self, bases: tuple[type, ...], /) -> tuple[type, ...]`
+info: rule `invalid-base` is enabled by default
+
+```
+
+```
+error[invalid-base]: Invalid class base with type `Bad2`
+ --> src/mdtest_snippet.py:16:15
+ |
+15 | class BadSub1(Bad1()): ... # error: [invalid-base]
+16 | class BadSub2(Bad2()): ... # error: [invalid-base]
+ | ^^^^^^
+ |
+info: Definition of class `BadSub2` will raise `TypeError` at runtime
+info: An instance type is only a valid class base if it has a valid `__mro_entries__` method
+info: Type `Bad2` has an `__mro_entries__` method, but it does not return a tuple of types
+info: rule `invalid-base` is enabled by default
+
+```
diff --git a/crates/ty_python_semantic/src/types/class_base.rs b/crates/ty_python_semantic/src/types/class_base.rs
index edb304fec1..9ff7fcad60 100644
--- a/crates/ty_python_semantic/src/types/class_base.rs
+++ b/crates/ty_python_semantic/src/types/class_base.rs
@@ -164,8 +164,12 @@ impl<'db> ClassBase<'db> {
}
}
Type::NominalInstance(_) => None, // TODO -- handle `__mro_entries__`?
- Type::PropertyInstance(_) => None,
- Type::Never
+
+ // This likely means that we're in unreachable code,
+ // in which case we want to treat `Never` in a forgiving way and silence diagnostics
+ Type::Never => Some(ClassBase::unknown()),
+
+ Type::PropertyInstance(_)
| Type::BooleanLiteral(_)
| Type::FunctionLiteral(_)
| Type::Callable(..)
diff --git a/crates/ty_python_semantic/src/types/diagnostic.rs b/crates/ty_python_semantic/src/types/diagnostic.rs
index c33590aab7..af7c678947 100644
--- a/crates/ty_python_semantic/src/types/diagnostic.rs
+++ b/crates/ty_python_semantic/src/types/diagnostic.rs
@@ -1,6 +1,7 @@
+use super::call::CallErrorKind;
use super::context::InferContext;
use super::mro::DuplicateBaseError;
-use super::{ClassBase, ClassLiteral, KnownClass};
+use super::{CallArgumentTypes, CallDunderError, ClassBase, ClassLiteral, KnownClass};
use crate::db::Db;
use crate::lint::{Level, LintRegistryBuilder, LintStatus};
use crate::suppression::FileSuppressionId;
@@ -70,6 +71,7 @@ pub(crate) fn register_lints(registry: &mut LintRegistryBuilder) {
registry.register_lint(&UNRESOLVED_ATTRIBUTE);
registry.register_lint(&UNRESOLVED_IMPORT);
registry.register_lint(&UNRESOLVED_REFERENCE);
+ registry.register_lint(&UNSUPPORTED_BASE);
registry.register_lint(&UNSUPPORTED_OPERATOR);
registry.register_lint(&ZERO_STEPSIZE_IN_SLICE);
registry.register_lint(&STATIC_ASSERT_ERROR);
@@ -451,14 +453,56 @@ declare_lint! {
}
declare_lint! {
- /// TODO #14889
+ /// ## What it does
+ /// Checks for class definitions that have bases which are not instances of `type`.
+ ///
+ /// ## Why is this bad?
+ /// Class definitions with bases like this will lead to `TypeError` being raised at runtime.
+ ///
+ /// ## Examples
+ /// ```python
+ /// class A(42): ... # error: [invalid-base]
+ /// ```
pub(crate) static INVALID_BASE = {
- summary: "detects invalid bases in class definitions",
+ summary: "detects class bases that will cause the class definition to raise an exception at runtime",
status: LintStatus::preview("1.0.0"),
default_level: Level::Error,
}
}
+declare_lint! {
+ /// ## What it does
+ /// Checks for class definitions that have bases which are unsupported by ty.
+ ///
+ /// ## Why is this bad?
+ /// If a class has a base that is an instance of a complex type such as a union type,
+ /// ty will not be able to resolve the [method resolution order] (MRO) for the class.
+ /// This will lead to an inferior understanding of your codebase and unpredictable
+ /// type-checking behavior.
+ ///
+ /// ## Examples
+ /// ```python
+ /// import datetime
+ ///
+ /// class A: ...
+ /// class B: ...
+ ///
+ /// if datetime.date.today().weekday() != 6:
+ /// C = A
+ /// else:
+ /// C = B
+ ///
+ /// class D(C): ... # error: [unsupported-base]
+ /// ```
+ ///
+ /// [method resolution order]: https://docs.python.org/3/glossary.html#term-method-resolution-order
+ pub(crate) static UNSUPPORTED_BASE = {
+ summary: "detects class bases that are unsupported as ty could not feasibly calculate the class's MRO",
+ status: LintStatus::preview("1.0.0"),
+ default_level: Level::Warn,
+ }
+}
+
declare_lint! {
/// ## What it does
/// Checks for expressions used in `with` statements
@@ -1976,3 +2020,132 @@ pub(crate) fn report_duplicate_bases(
diagnostic.sub(sub_diagnostic);
}
+
+pub(crate) fn report_invalid_or_unsupported_base(
+ context: &InferContext,
+ base_node: &ast::Expr,
+ base_type: Type,
+ class: ClassLiteral,
+) {
+ let db = context.db();
+ let instance_of_type = KnownClass::Type.to_instance(db);
+
+ if base_type.is_assignable_to(db, instance_of_type) {
+ report_unsupported_base(context, base_node, base_type, class);
+ return;
+ }
+
+ let tuple_of_types = KnownClass::Tuple.to_specialized_instance(db, [instance_of_type]);
+
+ let explain_mro_entries = |diagnostic: &mut LintDiagnosticGuard| {
+ diagnostic.info(
+ "An instance type is only a valid class base \
+ if it has a valid `__mro_entries__` method",
+ );
+ };
+
+ match base_type.try_call_dunder(
+ db,
+ "__mro_entries__",
+ CallArgumentTypes::positional([tuple_of_types]),
+ ) {
+ Ok(ret) => {
+ if ret.return_type(db).is_assignable_to(db, tuple_of_types) {
+ report_unsupported_base(context, base_node, base_type, class);
+ } else {
+ let Some(mut diagnostic) =
+ report_invalid_base(context, base_node, base_type, class)
+ else {
+ return;
+ };
+ explain_mro_entries(&mut diagnostic);
+ diagnostic.info(format_args!(
+ "Type `{}` has an `__mro_entries__` method, but it does not return a tuple of types",
+ base_type.display(db)
+ ));
+ }
+ }
+ Err(mro_entries_call_error) => {
+ let Some(mut diagnostic) = report_invalid_base(context, base_node, base_type, class)
+ else {
+ return;
+ };
+
+ match mro_entries_call_error {
+ CallDunderError::MethodNotAvailable => {}
+ CallDunderError::PossiblyUnbound(_) => {
+ explain_mro_entries(&mut diagnostic);
+ diagnostic.info(format_args!(
+ "Type `{}` has an `__mro_entries__` attribute, but it is possibly unbound",
+ base_type.display(db)
+ ));
+ }
+ CallDunderError::CallError(CallErrorKind::NotCallable, _) => {
+ explain_mro_entries(&mut diagnostic);
+ diagnostic.info(format_args!(
+ "Type `{}` has an `__mro_entries__` attribute, but it is not callable",
+ base_type.display(db)
+ ));
+ }
+ CallDunderError::CallError(CallErrorKind::BindingError, _) => {
+ explain_mro_entries(&mut diagnostic);
+ diagnostic.info(format_args!(
+ "Type `{}` has an `__mro_entries__` method, \
+ but it cannot be called with the expected arguments",
+ base_type.display(db)
+ ));
+ diagnostic.info(
+ "Expected a signature at least as permissive as \
+ `def __mro_entries__(self, bases: tuple[type, ...], /) -> tuple[type, ...]`"
+ );
+ }
+ CallDunderError::CallError(CallErrorKind::PossiblyNotCallable, _) => {
+ explain_mro_entries(&mut diagnostic);
+ diagnostic.info(format_args!(
+ "Type `{}` has an `__mro_entries__` method, \
+ but it may not be callable",
+ base_type.display(db)
+ ));
+ }
+ }
+ }
+ }
+}
+
+fn report_unsupported_base(
+ context: &InferContext,
+ base_node: &ast::Expr,
+ base_type: Type,
+ class: ClassLiteral,
+) {
+ let Some(builder) = context.report_lint(&UNSUPPORTED_BASE, base_node) else {
+ return;
+ };
+ let mut diagnostic = builder.into_diagnostic(format_args!(
+ "Unsupported class base with type `{}`",
+ base_type.display(context.db())
+ ));
+ diagnostic.info(format_args!(
+ "ty cannot resolve a consistent MRO for class `{}` due to this base",
+ class.name(context.db())
+ ));
+ diagnostic.info("Only class objects or `Any` are supported as class bases");
+}
+
+fn report_invalid_base<'ctx, 'db>(
+ context: &'ctx InferContext<'db>,
+ base_node: &ast::Expr,
+ base_type: Type<'db>,
+ class: ClassLiteral<'db>,
+) -> Option> {
+ let builder = context.report_lint(&INVALID_BASE, base_node)?;
+ let mut diagnostic = builder.into_diagnostic(format_args!(
+ "Invalid class base with type `{}`",
+ base_type.display(context.db())
+ ));
+ diagnostic.info(format_args!(
+ "Definition of class `{}` will raise `TypeError` at runtime",
+ class.name(context.db())
+ ));
+ Some(diagnostic)
+}
diff --git a/crates/ty_python_semantic/src/types/infer.rs b/crates/ty_python_semantic/src/types/infer.rs
index 403ce508ab..9ba6220198 100644
--- a/crates/ty_python_semantic/src/types/infer.rs
+++ b/crates/ty_python_semantic/src/types/infer.rs
@@ -102,8 +102,9 @@ use super::diagnostic::{
SUBCLASS_OF_FINAL_CLASS, TYPE_ASSERTION_FAILURE, report_attempted_protocol_instantiation,
report_bad_argument_to_get_protocol_members, report_duplicate_bases,
report_index_out_of_bounds, report_invalid_exception_caught, report_invalid_exception_cause,
- report_invalid_exception_raised, report_invalid_type_checking_constant,
- report_non_subscriptable, report_possibly_unresolved_reference,
+ report_invalid_exception_raised, report_invalid_or_unsupported_base,
+ report_invalid_type_checking_constant, report_non_subscriptable,
+ report_possibly_unresolved_reference,
report_runtime_check_against_non_runtime_checkable_protocol, report_slice_step_size_zero,
report_unresolved_reference,
};
@@ -892,63 +893,51 @@ impl<'db> TypeInferenceBuilder<'db> {
// (3) Check that the class's MRO is resolvable
match class.try_mro(self.db(), None) {
- Err(mro_error) => {
- match mro_error.reason() {
- MroErrorKind::DuplicateBases(duplicates) => {
- let base_nodes = class_node.bases();
- for duplicate in duplicates {
- report_duplicate_bases(&self.context, class, duplicate, base_nodes);
- }
- }
- MroErrorKind::InvalidBases(bases) => {
- let base_nodes = class_node.bases();
- for (index, base_ty) in bases {
- if base_ty.is_never() {
- // A class base of type `Never` can appear in unreachable code. It
- // does not indicate a problem, since the actual construction of the
- // class will never happen.
- continue;
- }
- let Some(builder) =
- self.context.report_lint(&INVALID_BASE, &base_nodes[*index])
- else {
- continue;
- };
- builder.into_diagnostic(format_args!(
- "Invalid class base with type `{}` \
- (all bases must be a class, `Any`, `Unknown` or `Todo`)",
- base_ty.display(self.db())
- ));
- }
- }
- MroErrorKind::UnresolvableMro { bases_list } => {
- if let Some(builder) =
- self.context.report_lint(&INCONSISTENT_MRO, class_node)
- {
- builder.into_diagnostic(format_args!(
- "Cannot create a consistent method resolution order (MRO) \
- for class `{}` with bases list `[{}]`",
- class.name(self.db()),
- bases_list
- .iter()
- .map(|base| base.display(self.db()))
- .join(", ")
- ));
- }
- }
- MroErrorKind::InheritanceCycle => {
- if let Some(builder) = self
- .context
- .report_lint(&CYCLIC_CLASS_DEFINITION, class_node)
- {
- builder.into_diagnostic(format_args!(
- "Cyclic definition of `{}` (class cannot inherit from itself)",
- class.name(self.db())
- ));
- }
+ Err(mro_error) => match mro_error.reason() {
+ MroErrorKind::DuplicateBases(duplicates) => {
+ let base_nodes = class_node.bases();
+ for duplicate in duplicates {
+ report_duplicate_bases(&self.context, class, duplicate, base_nodes);
}
}
- }
+ MroErrorKind::InvalidBases(bases) => {
+ let base_nodes = class_node.bases();
+ for (index, base_ty) in bases {
+ report_invalid_or_unsupported_base(
+ &self.context,
+ &base_nodes[*index],
+ *base_ty,
+ class,
+ );
+ }
+ }
+ MroErrorKind::UnresolvableMro { bases_list } => {
+ if let Some(builder) =
+ self.context.report_lint(&INCONSISTENT_MRO, class_node)
+ {
+ builder.into_diagnostic(format_args!(
+ "Cannot create a consistent method resolution order (MRO) \
+ for class `{}` with bases list `[{}]`",
+ class.name(self.db()),
+ bases_list
+ .iter()
+ .map(|base| base.display(self.db()))
+ .join(", ")
+ ));
+ }
+ }
+ MroErrorKind::InheritanceCycle => {
+ if let Some(builder) = self
+ .context
+ .report_lint(&CYCLIC_CLASS_DEFINITION, class_node)
+ {
+ builder.into_diagnostic(format_args!(
+ "Cyclic definition of `{}` (class cannot inherit from itself)",
+ class.name(self.db())
+ ));
+ }
+ }
+ },
Ok(_) => check_class_slots(&self.context, class, class_node),
}
diff --git a/crates/ty_python_semantic/src/types/mro.rs b/crates/ty_python_semantic/src/types/mro.rs
index c1120a2f76..151fbf6966 100644
--- a/crates/ty_python_semantic/src/types/mro.rs
+++ b/crates/ty_python_semantic/src/types/mro.rs
@@ -1,7 +1,8 @@
use std::collections::VecDeque;
use std::ops::Deref;
-use rustc_hash::FxHashMap;
+use indexmap::IndexMap;
+use rustc_hash::FxBuildHasher;
use crate::Db;
use crate::types::class_base::ClassBase;
@@ -157,8 +158,8 @@ impl<'db> Mro<'db> {
let mut duplicate_dynamic_bases = false;
let duplicate_bases: Vec> = {
- let mut base_to_indices: FxHashMap, Vec> =
- FxHashMap::default();
+ let mut base_to_indices: IndexMap, Vec, FxBuildHasher> =
+ IndexMap::default();
for (index, base) in valid_bases.iter().enumerate() {
base_to_indices.entry(*base).or_default().push(index);
diff --git a/ty.schema.json b/ty.schema.json
index 636912e0bb..48f089f198 100644
--- a/ty.schema.json
+++ b/ty.schema.json
@@ -401,8 +401,8 @@
]
},
"invalid-base": {
- "title": "detects invalid bases in class definitions",
- "description": "TODO #14889",
+ "title": "detects class bases that will cause the class definition to raise an exception at runtime",
+ "description": "## What it does\nChecks for class definitions that have bases which are not instances of `type`.\n\n## Why is this bad?\nClass definitions with bases like this will lead to `TypeError` being raised at runtime.\n\n## Examples\n```python\nclass A(42): ... # error: [invalid-base]\n```",
"default": "error",
"oneOf": [
{
@@ -800,6 +800,16 @@
}
]
},
+ "unsupported-base": {
+ "title": "detects class bases that are unsupported as ty could not feasibly calculate the class's MRO",
+ "description": "## What it does\nChecks for class definitions that have bases which are unsupported by ty.\n\n## Why is this bad?\nIf a class has a base that is an instance of a complex type such as a union type,\nty will not be able to resolve the [method resolution order] (MRO) for the class.\nThis will lead to an inferior understanding of your codebase and unpredictable\ntype-checking behavior.\n\n## Examples\n```python\nimport datetime\n\nclass A: ...\nclass B: ...\n\nif datetime.date.today().weekday() != 6:\n C = A\nelse:\n C = B\n\nclass D(C): ... # error: [unsupported-base]\n```\n\n[method resolution order]: https://docs.python.org/3/glossary.html#term-method-resolution-order",
+ "default": "warn",
+ "oneOf": [
+ {
+ "$ref": "#/definitions/Level"
+ }
+ ]
+ },
"unsupported-bool-conversion": {
"title": "detects boolean conversion where the object incorrectly implements `__bool__`",
"description": "## What it does\nChecks for bool conversions where the object doesn't correctly implement `__bool__`.\n\n## Why is this bad?\nIf an exception is raised when you attempt to evaluate the truthiness of an object,\nusing the object in a boolean context will fail at runtime.\n\n## Examples\n\n```python\nclass NotBoolable:\n __bool__ = None\n\nb1 = NotBoolable()\nb2 = NotBoolable()\n\nif b1: # exception raised here\n pass\n\nb1 and b2 # exception raised here\nnot b1 # exception raised here\nb1 < b2 < b1 # exception raised here\n```",