Emit a diagnostic for subclassing with order=True

crates/ty/docs/rules.md

@@ -39,7 +39,7 @@ def test(): -> "int":
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20call-non-callable" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L135" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L136" target="_blank">View source</a>
 </small>
 
 
@@ -63,7 +63,7 @@ Calling a non-callable object will raise a `TypeError` at runtime.
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20conflicting-argument-forms" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L179" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L180" target="_blank">View source</a>
 </small>
 
 
@@ -95,7 +95,7 @@ f(int)  # error
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20conflicting-declarations" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L205" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L206" target="_blank">View source</a>
 </small>
 
 
@@ -126,7 +126,7 @@ a = 1
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20conflicting-metaclass" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L230" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L231" target="_blank">View source</a>
 </small>
 
 
@@ -158,7 +158,7 @@ class C(A, B): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20cyclic-class-definition" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L256" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L257" target="_blank">View source</a>
 </small>
 
 
@@ -190,7 +190,7 @@ class B(A): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Preview (since <a href="https://github.com/astral-sh/ty/releases/tag/1.0.0">1.0.0</a>) ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20cyclic-type-alias-definition" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L282" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L283" target="_blank">View source</a>
 </small>
 
 
@@ -218,7 +218,7 @@ type B = A
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20duplicate-base" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L343" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L344" target="_blank">View source</a>
 </small>
 
 
@@ -245,7 +245,7 @@ class B(A, A): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.12">0.0.1-alpha.12</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20duplicate-kw-only" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L364" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L365" target="_blank">View source</a>
 </small>
 
 
@@ -357,7 +357,7 @@ def test(): -> "Literal[5]":
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20inconsistent-mro" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L568" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L569" target="_blank">View source</a>
 </small>
 
 
@@ -387,7 +387,7 @@ class C(A, B): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20index-out-of-bounds" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L592" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L593" target="_blank">View source</a>
 </small>
 
 
@@ -413,7 +413,7 @@ t[3]  # IndexError: tuple index out of range
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.12">0.0.1-alpha.12</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20instance-layout-conflict" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L396" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L397" target="_blank">View source</a>
 </small>
 
 
@@ -502,7 +502,7 @@ an atypical memory layout.
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-argument-type" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L646" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L647" target="_blank">View source</a>
 </small>
 
 
@@ -529,7 +529,7 @@ func("foo")  # error: [invalid-argument-type]
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-assignment" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L686" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L687" target="_blank">View source</a>
 </small>
 
 
@@ -557,7 +557,7 @@ a: int = ''
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-attribute-access" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1976" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2016" target="_blank">View source</a>
 </small>
 
 
@@ -591,7 +591,7 @@ C.instance_var = 3  # error: Cannot assign to instance variable
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.19">0.0.1-alpha.19</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-await" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L708" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L709" target="_blank">View source</a>
 </small>
 
 
@@ -627,7 +627,7 @@ asyncio.run(main())
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-base" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L738" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L739" target="_blank">View source</a>
 </small>
 
 
@@ -651,7 +651,7 @@ class A(42): ...  # error: [invalid-base]
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-context-manager" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L789" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L790" target="_blank">View source</a>
 </small>
 
 
@@ -678,7 +678,7 @@ with 1:
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-declaration" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L810" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L811" target="_blank">View source</a>
 </small>
 
 
@@ -707,7 +707,7 @@ a: str
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-exception-caught" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L833" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L834" target="_blank">View source</a>
 </small>
 
 
@@ -751,7 +751,7 @@ except ZeroDivisionError:
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.28">0.0.1-alpha.28</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-explicit-override" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1646" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1686" target="_blank">View source</a>
 </small>
 
 
@@ -793,7 +793,7 @@ class D(A):
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-generic-class" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L869" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L870" target="_blank">View source</a>
 </small>
 
 
@@ -826,7 +826,7 @@ class C[U](Generic[T]): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.17">0.0.1-alpha.17</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-key" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L613" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L614" target="_blank">View source</a>
 </small>
 
 
@@ -865,7 +865,7 @@ carol = Person(name="Carol", age=25)  # typo!
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-legacy-type-variable" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L895" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L896" target="_blank">View source</a>
 </small>
 
 
@@ -900,7 +900,7 @@ def f(t: TypeVar("U")): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-metaclass" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L992" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L993" target="_blank">View source</a>
 </small>
 
 
@@ -934,7 +934,7 @@ class B(metaclass=f): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.20">0.0.1-alpha.20</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-method-override" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2104" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2144" target="_blank">View source</a>
 </small>
 
 
@@ -1041,7 +1041,7 @@ Correct use of `@override` is enforced by ty's `invalid-explicit-override` rule.
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.19">0.0.1-alpha.19</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-named-tuple" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L542" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L543" target="_blank">View source</a>
 </small>
 
 
@@ -1073,7 +1073,7 @@ TypeError: can only inherit from a NamedTuple type and Generic
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Preview (since <a href="https://github.com/astral-sh/ty/releases/tag/1.0.0">1.0.0</a>) ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-newtype" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L968" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L969" target="_blank">View source</a>
 </small>
 
 
@@ -1103,7 +1103,7 @@ Baz = NewType("Baz", int | str)  # error: invalid base for `typing.NewType`
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-overload" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1019" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1020" target="_blank">View source</a>
 </small>
 
 
@@ -1153,7 +1153,7 @@ def foo(x: int) -> int: ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-parameter-default" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1118" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1119" target="_blank">View source</a>
 </small>
 
 
@@ -1179,7 +1179,7 @@ def f(a: int = ''): ...
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-paramspec" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L923" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L924" target="_blank">View source</a>
 </small>
 
 
@@ -1210,7 +1210,7 @@ P2 = ParamSpec("S2")  # error: ParamSpec name must match the variable it's assig
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-protocol" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L478" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L479" target="_blank">View source</a>
 </small>
 
 
@@ -1244,7 +1244,7 @@ TypeError: Protocols can only inherit from other protocols, got <class 'int'>
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-raise" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1138" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1139" target="_blank">View source</a>
 </small>
 
 
@@ -1293,7 +1293,7 @@ def g():
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-return-type" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L667" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L668" target="_blank">View source</a>
 </small>
 
 
@@ -1318,7 +1318,7 @@ def func() -> int:
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-super-argument" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1181" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1182" target="_blank">View source</a>
 </small>
 
 
@@ -1376,7 +1376,7 @@ TODO #14889
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.6">0.0.1-alpha.6</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-alias-type" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L947" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L948" target="_blank">View source</a>
 </small>
 
 
@@ -1403,7 +1403,7 @@ NewAlias = TypeAliasType(get_name(), int)        # error: TypeAliasType name mus
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.29">0.0.1-alpha.29</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-arguments" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1413" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1414" target="_blank">View source</a>
 </small>
 
 
@@ -1450,7 +1450,7 @@ Bar[int]  # error: too few arguments
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-checking-constant" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1220" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1221" target="_blank">View source</a>
 </small>
 
 
@@ -1480,7 +1480,7 @@ TYPE_CHECKING = ''
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-form" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1244" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1245" target="_blank">View source</a>
 </small>
 
 
@@ -1510,7 +1510,7 @@ b: Annotated[int]  # `Annotated` expects at least two arguments
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.11">0.0.1-alpha.11</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-guard-call" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1296" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1297" target="_blank">View source</a>
 </small>
 
 
@@ -1544,7 +1544,7 @@ f(10)  # Error
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.11">0.0.1-alpha.11</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-guard-definition" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1268" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1269" target="_blank">View source</a>
 </small>
 
 
@@ -1578,7 +1578,7 @@ class C:
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20invalid-type-variable-constraints" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1324" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1325" target="_blank">View source</a>
 </small>
 
 
@@ -1613,7 +1613,7 @@ T = TypeVar('T', bound=str)  # valid bound TypeVar
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20missing-argument" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1353" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1354" target="_blank">View source</a>
 </small>
 
 
@@ -1638,7 +1638,7 @@ func()  # TypeError: func() missing 1 required positional argument: 'x'
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.20">0.0.1-alpha.20</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20missing-typed-dict-key" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2077" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2117" target="_blank">View source</a>
 </small>
 
 
@@ -1671,7 +1671,7 @@ alice["age"]  # KeyError
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20no-matching-overload" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1372" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1373" target="_blank">View source</a>
 </small>
 
 
@@ -1700,7 +1700,7 @@ func("string")  # error: [no-matching-overload]
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20non-subscriptable" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1395" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1396" target="_blank">View source</a>
 </small>
 
 
@@ -1724,7 +1724,7 @@ Subscripting an object that does not support it will raise a `TypeError` at runt
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20not-iterable" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1454" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1455" target="_blank">View source</a>
 </small>
 
 
@@ -1750,7 +1750,7 @@ for i in 34:  # TypeError: 'int' object is not iterable
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.29">0.0.1-alpha.29</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20override-of-final-method" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1619" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1620" target="_blank">View source</a>
 </small>
 
 
@@ -1783,7 +1783,7 @@ class B(A):
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20parameter-already-assigned" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1505" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1506" target="_blank">View source</a>
 </small>
 
 
@@ -1810,7 +1810,7 @@ f(1, x=2)  # Error raised here
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.22">0.0.1-alpha.22</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20positional-only-parameter-as-kwarg" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1830" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1870" target="_blank">View source</a>
 </small>
 
 
@@ -1868,7 +1868,7 @@ def test(): -> "int":
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20static-assert-error" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1952" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1992" target="_blank">View source</a>
 </small>
 
 
@@ -1898,7 +1898,7 @@ static_assert(int(2.0 * 3.0) == 6)  # error: does not have a statically known tr
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20subclass-of-final-class" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1596" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1597" target="_blank">View source</a>
 </small>
 
 
@@ -1927,7 +1927,7 @@ class B(A): ...  # Error raised here
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Preview (since <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.30">0.0.1-alpha.30</a>) ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20super-call-in-named-tuple-method" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1764" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1804" target="_blank">View source</a>
 </small>
 
 
@@ -1961,7 +1961,7 @@ class F(NamedTuple):
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20too-many-positional-arguments" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1704" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1744" target="_blank">View source</a>
 </small>
 
 
@@ -1988,7 +1988,7 @@ f("foo")  # Error raised here
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20type-assertion-failure" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1682" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1722" target="_blank">View source</a>
 </small>
 
 
@@ -2016,7 +2016,7 @@ def _(x: int):
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unavailable-implicit-super-arguments" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1725" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1765" target="_blank">View source</a>
 </small>
 
 
@@ -2062,7 +2062,7 @@ class A:
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unknown-argument" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1809" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1849" target="_blank">View source</a>
 </small>
 
 
@@ -2089,7 +2089,7 @@ f(x=1, y=2)  # Error raised here
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unresolved-attribute" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1851" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1891" target="_blank">View source</a>
 </small>
 
 
@@ -2117,7 +2117,7 @@ A().foo  # AttributeError: 'A' object has no attribute 'foo'
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unresolved-import" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1873" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1913" target="_blank">View source</a>
 </small>
 
 
@@ -2142,7 +2142,7 @@ import foo  # ModuleNotFoundError: No module named 'foo'
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unresolved-reference" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1892" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1932" target="_blank">View source</a>
 </small>
 
 
@@ -2167,7 +2167,7 @@ print(x)  # NameError: name 'x' is not defined
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unsupported-bool-conversion" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1474" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1475" target="_blank">View source</a>
 </small>
 
 
@@ -2204,7 +2204,7 @@ b1 < b2 < b1  # exception raised here
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unsupported-operator" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1911" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1951" target="_blank">View source</a>
 </small>
 
 
@@ -2232,7 +2232,7 @@ A() + A()  # TypeError: unsupported operand type(s) for +: 'A' and 'A'
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'error'."><code>error</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20zero-stepsize-in-slice" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1933" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1973" target="_blank">View source</a>
 </small>
 
 
@@ -2257,7 +2257,7 @@ l[1:10:0]  # ValueError: slice step cannot be zero
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.20">0.0.1-alpha.20</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20ambiguous-protocol-member" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L507" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L508" target="_blank">View source</a>
 </small>
 
 
@@ -2298,7 +2298,7 @@ class SubProto(BaseProto, Protocol):
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.16">0.0.1-alpha.16</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20deprecated" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L322" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L323" target="_blank">View source</a>
 </small>
 
 
@@ -2386,7 +2386,7 @@ a = 20 / 0  # type: ignore
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.22">0.0.1-alpha.22</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20possibly-missing-attribute" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1526" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1527" target="_blank">View source</a>
 </small>
 
 
@@ -2414,7 +2414,7 @@ A.c  # AttributeError: type object 'A' has no attribute 'c'
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.22">0.0.1-alpha.22</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20possibly-missing-implicit-call" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L153" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L154" target="_blank">View source</a>
 </small>
 
 
@@ -2446,7 +2446,7 @@ A()[0]  # TypeError: 'A' object is not subscriptable
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.22">0.0.1-alpha.22</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20possibly-missing-import" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1548" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1549" target="_blank">View source</a>
 </small>
 
 
@@ -2478,7 +2478,7 @@ from module import a  # ImportError: cannot import name 'a' from 'module'
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20redundant-cast" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2004" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2044" target="_blank">View source</a>
 </small>
 
 
@@ -2499,13 +2499,58 @@ def f() -> int:
 cast(int, f())  # Redundant
 ```
 
+## `subclass-of-dataclass-with-order`
+
+<small>
+Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
+Preview (since <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.30">0.0.1-alpha.30</a>) ·
+<a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20subclass-of-dataclass-with-order" target="_blank">Related issues</a> ·
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1647" target="_blank">View source</a>
+</small>
+
+
+**What it does**
+
+Checks for classes that inherit from a dataclass with `order=True`.
+
+**Why is this bad?**
+
+When a dataclass has `order=True`, comparison methods (`__lt__`, `__le__`, `__gt__`, `__ge__`)
+are generated that compare instances as tuples of their fields. These methods raise a
+`TypeError` at runtime when comparing instances of different classes in the inheritance
+hierarchy, even if one is a subclass of the other.
+
+This violates the [Liskov Substitution Principle] because child class instances cannot be
+used in all contexts where parent class instances are expected.
+
+**Example**
+
+
+```python
+from dataclasses import dataclass
+
+@dataclass(order=True)
+class Parent:
+    value: int
+
+class Child(Parent):  # Error raised here
+    pass
+
+# At runtime, this raises TypeError:
+# Child(1) < Parent(2)
+```
+
+Consider using `functools.total_ordering` instead, which does not have this limitation.
+
+[Liskov Substitution Principle]: https://en.wikipedia.org/wiki/Liskov_substitution_principle
+
 ## `undefined-reveal`
 
 <small>
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20undefined-reveal" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1791" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1831" target="_blank">View source</a>
 </small>
 
 
@@ -2529,7 +2574,7 @@ reveal_type(1)  # NameError: name 'reveal_type' is not defined
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.15">0.0.1-alpha.15</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unresolved-global" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2025" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L2065" target="_blank">View source</a>
 </small>
 
 
@@ -2587,7 +2632,7 @@ def g():
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.7">0.0.1-alpha.7</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20unsupported-base" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L756" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L757" target="_blank">View source</a>
 </small>
 
 
@@ -2626,7 +2671,7 @@ class D(C): ...  # error: [unsupported-base]
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'warn'."><code>warn</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.22">0.0.1-alpha.22</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20useless-overload-body" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1062" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1063" target="_blank">View source</a>
 </small>
 
 
@@ -2689,7 +2734,7 @@ def foo(x: int | str) -> int | str:
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'ignore'."><code>ignore</code></a> ·
 Preview (since <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a>) ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20division-by-zero" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L304" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L305" target="_blank">View source</a>
 </small>
 
 
@@ -2713,7 +2758,7 @@ Dividing by zero raises a `ZeroDivisionError` at runtime.
 Default level: <a href="../rules.md#rule-levels" title="This lint has a default level of 'ignore'."><code>ignore</code></a> ·
 Added in <a href="https://github.com/astral-sh/ty/releases/tag/0.0.1-alpha.1">0.0.1-alpha.1</a> ·
 <a href="https://github.com/astral-sh/ty/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20possibly-unresolved-reference" target="_blank">Related issues</a> ·
-<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1574" target="_blank">View source</a>
+<a href="https://github.com/astral-sh/ruff/blob/main/crates%2Fty_python_semantic%2Fsrc%2Ftypes%2Fdiagnostic.rs#L1575" target="_blank">View source</a>
 </small>
 
 

crates/ty_python_semantic/resources/mdtest/dataclasses/dataclasses.md

@@ -349,6 +349,49 @@ GenericWithOrder[int](1) < GenericWithOrder[int](1)
 GenericWithOrder[int](1) < GenericWithOrder[str]("a")  # error: [unsupported-operator]
 ```
 
+Subclassing a dataclass with `order=True` is problematic because comparing instances of different
+classes in the inheritance hierarchy will raise a `TypeError` at runtime. This violates the Liskov
+Substitution Principle:
+
+```py
+from dataclasses import dataclass
+
+@dataclass(order=True)
+class Parent:
+    value: int
+
+class Child(Parent):  # error: [subclass-of-dataclass-with-order]
+    pass
+
+# The comparison methods generated by @dataclass(order=True) compare instances
+# as tuples of their fields. At runtime, this raises TypeError when comparing
+# instances of different classes in the hierarchy:
+#   Child(42) < Parent(42)  # TypeError!
+```
+
+This also applies when the child class is also a dataclass:
+
+```py
+@dataclass(order=True)
+class OrderedParent:
+    x: int
+
+@dataclass
+class OrderedChild(OrderedParent):  # error: [subclass-of-dataclass-with-order]
+    y: str
+```
+
+If the parent dataclass does not have `order=True`, no warning is emitted:
+
+```py
+@dataclass
+class UnorderedParent:
+    x: int
+
+class UnorderedChild(UnorderedParent):  # No warning
+    pass
+```
+
 If a class already defines one of the comparison methods, a `TypeError` is raised at runtime.
 Ideally, we would emit a diagnostic in that case:
 

crates/ty_python_semantic/resources/mdtest/liskov.md

@@ -475,37 +475,24 @@ from typing import NamedTuple
 class Foo:
     x: int
 
-class Bar(Foo):
+class Bar(Foo):  # error: [subclass-of-dataclass-with-order]
     def __lt__(self, other: Bar) -> bool: ...  # error: [invalid-method-override]
 
-# TODO: specifying `order=True` on the subclass means that a `__lt__` method is
+# Specifying `order=True` on the subclass means that a `__lt__` method is generated that
-# generated that is incompatible with the generated `__lt__` method on the superclass.
+# is incompatible with the generated `__lt__` method on the superclass. We emit a diagnostic
-# We could consider detecting this and emitting a diagnostic, though maybe it shouldn't
+# on the class definition because the design of `order=True` dataclasses themselves violates
-# be `invalid-method-override` since we'd emit it on the class definition rather than
+# the Liskov Substitution Principle.
-# on any method definition. Note also that no other type checker complains about this
-# as of 2025-11-21.
 @dataclass(order=True)
-class Bar2(Foo):
+class Bar2(Foo):  # error: [subclass-of-dataclass-with-order]
     y: str
 
-# TODO: Although this class does not override any methods of `Foo`, the design of the
+# Although this class does not override any methods of `Foo`, the design of the
-# `order=True` stdlib dataclasses feature itself arguably violates the Liskov Substitution
+# `order=True` stdlib dataclasses feature itself violates the Liskov Substitution
 # Principle! Instances of `Bar3` cannot be substituted wherever an instance of `Foo` is
 # expected, because the generated `__lt__` method on `Foo` raises an error unless the r.h.s.
 # and `l.h.s.` have exactly the same `__class__` (it does not permit instances of `Foo` to
 # be compared with instances of subclasses of `Foo`).
-#
+class Bar3(Foo): ...  # error: [subclass-of-dataclass-with-order]
-# Many users would probably like their type checkers to alert them to cases where instances
-# of subclasses cannot be substituted for instances of superclasses, as this violates many
-# assumptions a type checker will make and makes it likely that a type checker will fail to
-# catch type errors elsewhere in the user's code. We could therefore consider treating all
-# `order=True` dataclasses as implicitly `@final` in order to enforce soundness. However,
-# this probably shouldn't be reported with the same error code as Liskov violations, since
-# the error does not stem from any method signatures written by the user. The example is
-# only included here for completeness.
-#
-# Note that no other type checker catches this error as of 2025-11-21.
-class Bar3(Foo): ...
 
 class Eggs:
     def __lt__(self, other: Eggs) -> bool: ...

crates/ty_python_semantic/resources/mdtest/override.md

@@ -275,7 +275,7 @@ from dataclasses import dataclass
 class ParentDataclass:
     x: int
 
-class Child(ParentDataclass):
+class Child(ParentDataclass):  # error: [subclass-of-dataclass-with-order]
     @override
     def __lt__(self, other: ParentDataclass) -> bool: ...  # fine
 

crates/ty_python_semantic/resources/mdtest/snapshots/liskov.md_-_The_Liskov_Substitut…_-_Synthesized_methods_(9e6e6c7368530460).snap

@@ -1,5 +1,6 @@
 ---
 source: crates/ty_test/src/lib.rs
+assertion_line: 523
 expression: snapshot
 ---
 ---
@@ -19,66 +20,67 @@ mdtest path: crates/ty_python_semantic/resources/mdtest/liskov.md
  5 | class Foo:
  6 |     x: int
  7 | 
- 8 | class Bar(Foo):
+ 8 | class Bar(Foo):  # error: [subclass-of-dataclass-with-order]
  9 |     def __lt__(self, other: Bar) -> bool: ...  # error: [invalid-method-override]
 10 | 
-11 | # TODO: specifying `order=True` on the subclass means that a `__lt__` method is
+11 | # Specifying `order=True` on the subclass means that a `__lt__` method is generated that
-12 | # generated that is incompatible with the generated `__lt__` method on the superclass.
+12 | # is incompatible with the generated `__lt__` method on the superclass. We emit a diagnostic
-13 | # We could consider detecting this and emitting a diagnostic, though maybe it shouldn't
+13 | # on the class definition because the design of `order=True` dataclasses themselves violates
-14 | # be `invalid-method-override` since we'd emit it on the class definition rather than
+14 | # the Liskov Substitution Principle.
-15 | # on any method definition. Note also that no other type checker complains about this
+15 | @dataclass(order=True)
-16 | # as of 2025-11-21.
+16 | class Bar2(Foo):  # error: [subclass-of-dataclass-with-order]
-17 | @dataclass(order=True)
+17 |     y: str
-18 | class Bar2(Foo):
+18 | 
-19 |     y: str
+19 | # Although this class does not override any methods of `Foo`, the design of the
-20 | 
+20 | # `order=True` stdlib dataclasses feature itself violates the Liskov Substitution
-21 | # TODO: Although this class does not override any methods of `Foo`, the design of the
+21 | # Principle! Instances of `Bar3` cannot be substituted wherever an instance of `Foo` is
-22 | # `order=True` stdlib dataclasses feature itself arguably violates the Liskov Substitution
+22 | # expected, because the generated `__lt__` method on `Foo` raises an error unless the r.h.s.
-23 | # Principle! Instances of `Bar3` cannot be substituted wherever an instance of `Foo` is
+23 | # and `l.h.s.` have exactly the same `__class__` (it does not permit instances of `Foo` to
-24 | # expected, because the generated `__lt__` method on `Foo` raises an error unless the r.h.s.
+24 | # be compared with instances of subclasses of `Foo`).
-25 | # and `l.h.s.` have exactly the same `__class__` (it does not permit instances of `Foo` to
+25 | class Bar3(Foo): ...  # error: [subclass-of-dataclass-with-order]
-26 | # be compared with instances of subclasses of `Foo`).
+26 | 
-27 | #
+27 | class Eggs:
-28 | # Many users would probably like their type checkers to alert them to cases where instances
+28 |     def __lt__(self, other: Eggs) -> bool: ...
-29 | # of subclasses cannot be substituted for instances of superclasses, as this violates many
+29 | 
-30 | # assumptions a type checker will make and makes it likely that a type checker will fail to
+30 | # TODO: the generated `Ham.__lt__` method here incompatibly overrides `Eggs.__lt__`.
-31 | # catch type errors elsewhere in the user's code. We could therefore consider treating all
+31 | # We could consider emitting a diagnostic here. As of 2025-11-21, mypy reports a
-32 | # `order=True` dataclasses as implicitly `@final` in order to enforce soundness. However,
+32 | # diagnostic here but pyright and pyrefly do not.
-33 | # this probably shouldn't be reported with the same error code as Liskov violations, since
+33 | @dataclass(order=True)
-34 | # the error does not stem from any method signatures written by the user. The example is
+34 | class Ham(Eggs):
-35 | # only included here for completeness.
+35 |     x: int
-36 | #
+36 | 
-37 | # Note that no other type checker catches this error as of 2025-11-21.
+37 | class Baz(NamedTuple):
-38 | class Bar3(Foo): ...
+38 |     x: int
 39 | 
-40 | class Eggs:
+40 | class Spam(Baz):
-41 |     def __lt__(self, other: Eggs) -> bool: ...
+41 |     def _asdict(self) -> tuple[int, ...]: ...  # error: [invalid-method-override]
-42 | 
-43 | # TODO: the generated `Ham.__lt__` method here incompatibly overrides `Eggs.__lt__`.
-44 | # We could consider emitting a diagnostic here. As of 2025-11-21, mypy reports a
-45 | # diagnostic here but pyright and pyrefly do not.
-46 | @dataclass(order=True)
-47 | class Ham(Eggs):
-48 |     x: int
-49 | 
-50 | class Baz(NamedTuple):
-51 |     x: int
-52 | 
-53 | class Spam(Baz):
-54 |     def _asdict(self) -> tuple[int, ...]: ...  # error: [invalid-method-override]
 ```
 
 # Diagnostics
 
+```
+warning[subclass-of-dataclass-with-order]: Class `Bar` inherits from dataclass `Foo` which has `order=True`
+ --> src/mdtest_snippet.pyi:8:11
+  |
+6 |     x: int
+7 |
+8 | class Bar(Foo):  # error: [subclass-of-dataclass-with-order]
+  |           ^^^
+9 |     def __lt__(self, other: Bar) -> bool: ...  # error: [invalid-method-override]
+  |
+info: rule `subclass-of-dataclass-with-order` is enabled by default
+
+```
+
 ```
 error[invalid-method-override]: Invalid override of method `__lt__`
   --> src/mdtest_snippet.pyi:9:9
    |
- 8 | class Bar(Foo):
+ 8 | class Bar(Foo):  # error: [subclass-of-dataclass-with-order]
  9 |     def __lt__(self, other: Bar) -> bool: ...  # error: [invalid-method-override]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Definition is incompatible with `Foo.__lt__`
 10 |
-11 | # TODO: specifying `order=True` on the subclass means that a `__lt__` method is
+11 | # Specifying `order=True` on the subclass means that a `__lt__` method is generated that
    |
 info: This violates the Liskov Substitution Principle
 info: `Foo.__lt__` is a generated method created because `Foo` is a dataclass
@@ -94,22 +96,51 @@ info: rule `invalid-method-override` is enabled by default
 ```
 
 ```
-error[invalid-method-override]: Invalid override of method `_asdict`
+warning[subclass-of-dataclass-with-order]: Class `Bar2` inherits from dataclass `Foo` which has `order=True`
-  --> src/mdtest_snippet.pyi:54:9
+  --> src/mdtest_snippet.pyi:16:12
    |
-53 | class Spam(Baz):
+14 | # the Liskov Substitution Principle.
-54 |     def _asdict(self) -> tuple[int, ...]: ...  # error: [invalid-method-override]
+15 | @dataclass(order=True)
+16 | class Bar2(Foo):  # error: [subclass-of-dataclass-with-order]
+   |            ^^^
+17 |     y: str
+   |
+info: rule `subclass-of-dataclass-with-order` is enabled by default
+
+```
+
+```
+warning[subclass-of-dataclass-with-order]: Class `Bar3` inherits from dataclass `Foo` which has `order=True`
+  --> src/mdtest_snippet.pyi:25:12
+   |
+23 | # and `l.h.s.` have exactly the same `__class__` (it does not permit instances of `Foo` to
+24 | # be compared with instances of subclasses of `Foo`).
+25 | class Bar3(Foo): ...  # error: [subclass-of-dataclass-with-order]
+   |            ^^^
+26 |
+27 | class Eggs:
+   |
+info: rule `subclass-of-dataclass-with-order` is enabled by default
+
+```
+
+```
+error[invalid-method-override]: Invalid override of method `_asdict`
+  --> src/mdtest_snippet.pyi:41:9
+   |
+40 | class Spam(Baz):
+41 |     def _asdict(self) -> tuple[int, ...]: ...  # error: [invalid-method-override]
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Definition is incompatible with `Baz._asdict`
    |
 info: This violates the Liskov Substitution Principle
 info: `Baz._asdict` is a generated method created because `Baz` inherits from `typing.NamedTuple`
-  --> src/mdtest_snippet.pyi:50:7
+  --> src/mdtest_snippet.pyi:37:7
    |
-48 |     x: int
+35 |     x: int
-49 |
+36 |
-50 | class Baz(NamedTuple):
+37 | class Baz(NamedTuple):
    |       ^^^^^^^^^^^^^^^ Definition of `Baz`
-51 |     x: int
+38 |     x: int
    |
 info: rule `invalid-method-override` is enabled by default
 

crates/ty_python_semantic/src/types/diagnostic.rs

@@ -122,6 +122,7 @@ pub(crate) fn register_lints(registry: &mut LintRegistryBuilder) {
     registry.register_lint(&INVALID_METHOD_OVERRIDE);
     registry.register_lint(&INVALID_EXPLICIT_OVERRIDE);
     registry.register_lint(&SUPER_CALL_IN_NAMED_TUPLE_METHOD);
+    registry.register_lint(&SUBCLASS_OF_DATACLASS_WITH_ORDER);
 
     // String annotations
     registry.register_lint(&BYTE_STRING_TYPE_ANNOTATION);
@@ -1643,6 +1644,45 @@ declare_lint! {
     }
 }
 
+declare_lint! {
+    /// ## What it does
+    /// Checks for classes that inherit from a dataclass with `order=True`.
+    ///
+    /// ## Why is this bad?
+    /// When a dataclass has `order=True`, comparison methods (`__lt__`, `__le__`, `__gt__`, `__ge__`)
+    /// are generated that compare instances as tuples of their fields. These methods raise a
+    /// `TypeError` at runtime when comparing instances of different classes in the inheritance
+    /// hierarchy, even if one is a subclass of the other.
+    ///
+    /// This violates the [Liskov Substitution Principle] because child class instances cannot be
+    /// used in all contexts where parent class instances are expected.
+    ///
+    /// ## Example
+    ///
+    /// ```python
+    /// from dataclasses import dataclass
+    ///
+    /// @dataclass(order=True)
+    /// class Parent:
+    ///     value: int
+    ///
+    /// class Child(Parent):  # Error raised here
+    ///     pass
+    ///
+    /// # At runtime, this raises TypeError:
+    /// # Child(1) < Parent(2)
+    /// ```
+    ///
+    /// Consider using `functools.total_ordering` instead, which does not have this limitation.
+    ///
+    /// [Liskov Substitution Principle]: https://en.wikipedia.org/wiki/Liskov_substitution_principle
+    pub(crate) static SUBCLASS_OF_DATACLASS_WITH_ORDER = {
+        summary: "detects subclasses of dataclasses with `order=True`",
+        status: LintStatus::preview("0.0.1-alpha.30"),
+        default_level: Level::Warn,
+    }
+}
+
 declare_lint! {
     /// ## What it does
     /// Checks for methods that are decorated with `@override` but do not override any method in a superclass.

crates/ty_python_semantic/src/types/infer/builder.rs

@@ -63,9 +63,9 @@ use crate::types::diagnostic::{
     INVALID_PARAMETER_DEFAULT, INVALID_PARAMSPEC, INVALID_PROTOCOL, INVALID_TYPE_ARGUMENTS,
     INVALID_TYPE_FORM, INVALID_TYPE_GUARD_CALL, INVALID_TYPE_VARIABLE_CONSTRAINTS,
     IncompatibleBases, NON_SUBSCRIPTABLE, POSSIBLY_MISSING_ATTRIBUTE,
-    POSSIBLY_MISSING_IMPLICIT_CALL, POSSIBLY_MISSING_IMPORT, SUBCLASS_OF_FINAL_CLASS,
+    POSSIBLY_MISSING_IMPLICIT_CALL, POSSIBLY_MISSING_IMPORT, SUBCLASS_OF_DATACLASS_WITH_ORDER,
-    UNDEFINED_REVEAL, UNRESOLVED_ATTRIBUTE, UNRESOLVED_GLOBAL, UNRESOLVED_IMPORT,
+    SUBCLASS_OF_FINAL_CLASS, UNDEFINED_REVEAL, UNRESOLVED_ATTRIBUTE, UNRESOLVED_GLOBAL,
-    UNRESOLVED_REFERENCE, UNSUPPORTED_OPERATOR, USELESS_OVERLOAD_BODY,
+    UNRESOLVED_IMPORT, UNRESOLVED_REFERENCE, UNSUPPORTED_OPERATOR, USELESS_OVERLOAD_BODY,
     hint_if_stdlib_attribute_exists_on_other_versions,
     hint_if_stdlib_submodule_exists_on_other_versions, report_attempted_protocol_instantiation,
     report_bad_dunder_set_call, report_cannot_pop_required_field_on_typed_dict,
@@ -103,13 +103,14 @@ use crate::types::typed_dict::{
 use crate::types::visitor::any_over_type;
 use crate::types::{
     CallDunderError, CallableBinding, CallableType, CallableTypes, ClassLiteral, ClassType,
-    DataclassParams, DynamicType, InternedType, IntersectionBuilder, IntersectionType, KnownClass,
+    DataclassFlags, DataclassParams, DynamicType, InternedType, IntersectionBuilder,
-    KnownInstanceType, LintDiagnosticGuard, MemberLookupPolicy, MetaclassCandidate,
+    IntersectionType, KnownClass, KnownInstanceType, LintDiagnosticGuard, MemberLookupPolicy,
-    PEP695TypeAliasType, ParameterForm, SpecialFormType, SubclassOfType, TrackedConstraintSet,
+    MetaclassCandidate, PEP695TypeAliasType, ParameterForm, SpecialFormType, SubclassOfType,
-    Truthiness, Type, TypeAliasType, TypeAndQualifiers, TypeContext, TypeQualifiers,
+    TrackedConstraintSet, Truthiness, Type, TypeAliasType, TypeAndQualifiers, TypeContext,
-    TypeVarBoundOrConstraints, TypeVarBoundOrConstraintsEvaluation, TypeVarDefaultEvaluation,
+    TypeQualifiers, TypeVarBoundOrConstraints, TypeVarBoundOrConstraintsEvaluation,
-    TypeVarIdentity, TypeVarInstance, TypeVarKind, TypeVarVariance, TypedDictType, UnionBuilder,
+    TypeVarDefaultEvaluation, TypeVarIdentity, TypeVarInstance, TypeVarKind, TypeVarVariance,
-    UnionType, UnionTypeInstance, binding_type, infer_scope_types, overrides, todo_type,
+    TypedDictType, UnionBuilder, UnionType, UnionTypeInstance, binding_type, infer_scope_types,
+    overrides, todo_type,
 };
 use crate::types::{ClassBase, add_inferred_python_version_hint_to_diagnostic};
 use crate::unpack::{EvaluationMode, UnpackPosition};
@@ -743,6 +744,22 @@ impl<'db, 'ast> TypeInferenceBuilder<'db, 'ast> {
                         ));
                     }
                 }
+
+                let (base_class_literal, _) = base_class.class_literal(self.db());
+                if let Some(base_params) = base_class_literal.dataclass_params(self.db()) {
+                    if base_params.flags(self.db()).contains(DataclassFlags::ORDER) {
+                        if let Some(builder) = self
+                            .context
+                            .report_lint(&SUBCLASS_OF_DATACLASS_WITH_ORDER, &class_node.bases()[i])
+                        {
+                            builder.into_diagnostic(format_args!(
+                                "Class `{}` inherits from dataclass `{}` which has `order=True`",
+                                class.name(self.db()),
+                                base_class.name(self.db()),
+                            ));
+                        }
+                    }
+                }
             }
 
             // (4) Check that the class's MRO is resolvable

crates/ty_server/tests/e2e/snapshots/e2e__commands__debug_command.snap

@@ -92,6 +92,7 @@ Settings: Settings {
         "raw-string-type-annotation": Error (Default),
         "redundant-cast": Warning (Default),
         "static-assert-error": Error (Default),
+        "subclass-of-dataclass-with-order": Warning (Default),
         "subclass-of-final-class": Error (Default),
         "super-call-in-named-tuple-method": Error (Default),
         "too-many-positional-arguments": Error (Default),

ty.schema.json

@@ -963,6 +963,16 @@
             }
           ]
         },
+        "subclass-of-dataclass-with-order": {
+          "title": "detects subclasses of dataclasses with `order=True`",
+          "description": "## What it does\nChecks for classes that inherit from a dataclass with `order=True`.\n\n## Why is this bad?\nWhen a dataclass has `order=True`, comparison methods (`__lt__`, `__le__`, `__gt__`, `__ge__`)\nare generated that compare instances as tuples of their fields. These methods raise a\n`TypeError` at runtime when comparing instances of different classes in the inheritance\nhierarchy, even if one is a subclass of the other.\n\nThis violates the [Liskov Substitution Principle] because child class instances cannot be\nused in all contexts where parent class instances are expected.\n\n## Example\n\n```python\nfrom dataclasses import dataclass\n\n@dataclass(order=True)\nclass Parent:\n    value: int\n\nclass Child(Parent):  # Error raised here\n    pass\n\n# At runtime, this raises TypeError:\n# Child(1) < Parent(2)\n```\n\nConsider using `functools.total_ordering` instead, which does not have this limitation.\n\n[Liskov Substitution Principle]: https://en.wikipedia.org/wiki/Liskov_substitution_principle",
+          "default": "warn",
+          "oneOf": [
+            {
+              "$ref": "#/definitions/Level"
+            }
+          ]
+        },
         "subclass-of-final-class": {
           "title": "detects subclasses of final classes",
           "description": "## What it does\nChecks for classes that subclass final classes.\n\n## Why is this bad?\nDecorating a class with `@final` declares to the type checker that it should not be subclassed.\n\n## Example\n\n```python\nfrom typing import final\n\n@final\nclass A: ...\nclass B(A): ...  # Error raised here\n```",