From 77c8ddf10189aff5511dcf60fb427ea6a6e711fb Mon Sep 17 00:00:00 2001
From: Alex Waygood <Alex.Waygood@Gmail.com>
Date: Fri, 30 May 2025 16:49:20 +0100
Subject: [PATCH] [ty] Fix broken property tests for disjointness (#18384)

---
 .../type_properties/is_disjoint_from.md       | 11 ++++++++++
 crates/ty_python_semantic/src/types.rs        | 21 +++++++++----------
 2 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/crates/ty_python_semantic/resources/mdtest/type_properties/is_disjoint_from.md b/crates/ty_python_semantic/resources/mdtest/type_properties/is_disjoint_from.md
index 46cf9c9074..a39826671b 100644
--- a/crates/ty_python_semantic/resources/mdtest/type_properties/is_disjoint_from.md
+++ b/crates/ty_python_semantic/resources/mdtest/type_properties/is_disjoint_from.md
@@ -454,15 +454,23 @@ static_assert(is_disjoint_from(bool, Callable[..., Any]))
 static_assert(is_disjoint_from(C, Callable[..., Any]))
 static_assert(is_disjoint_from(bool | C, Callable[..., Any]))
 
+static_assert(is_disjoint_from(Callable[..., Any], bool))
+static_assert(is_disjoint_from(Callable[..., Any], C))
+static_assert(is_disjoint_from(Callable[..., Any], bool | C))
+
 static_assert(not is_disjoint_from(str, Callable[..., Any]))
 static_assert(not is_disjoint_from(bool | str, Callable[..., Any]))
 
+static_assert(not is_disjoint_from(Callable[..., Any], str))
+static_assert(not is_disjoint_from(Callable[..., Any], bool | str))
+
 def bound_with_valid_type():
     @final
     class D:
         def __call__(self, *args: Any, **kwargs: Any) -> Any: ...
 
     static_assert(not is_disjoint_from(D, Callable[..., Any]))
+    static_assert(not is_disjoint_from(Callable[..., Any], D))
 
 def possibly_unbound_with_valid_type(flag: bool):
     @final
@@ -471,6 +479,7 @@ def possibly_unbound_with_valid_type(flag: bool):
             def __call__(self, *args: Any, **kwargs: Any) -> Any: ...
 
     static_assert(not is_disjoint_from(E, Callable[..., Any]))
+    static_assert(not is_disjoint_from(Callable[..., Any], E))
 
 def bound_with_invalid_type():
     @final
@@ -478,6 +487,7 @@ def bound_with_invalid_type():
         __call__: int = 1
 
     static_assert(is_disjoint_from(F, Callable[..., Any]))
+    static_assert(is_disjoint_from(Callable[..., Any], F))
 
 def possibly_unbound_with_invalid_type(flag: bool):
     @final
@@ -486,4 +496,5 @@ def possibly_unbound_with_invalid_type(flag: bool):
             __call__: int = 1
 
     static_assert(is_disjoint_from(G, Callable[..., Any]))
+    static_assert(is_disjoint_from(Callable[..., Any], G))
 ```
diff --git a/crates/ty_python_semantic/src/types.rs b/crates/ty_python_semantic/src/types.rs
index f885b45f58..f125540688 100644
--- a/crates/ty_python_semantic/src/types.rs
+++ b/crates/ty_python_semantic/src/types.rs
@@ -2180,23 +2180,22 @@ impl<'db> Type<'db> {
 
             (
                 Type::Callable(_) | Type::DataclassDecorator(_) | Type::DataclassTransformer(_),
-                Type::NominalInstance(instance),
+                instance @ Type::NominalInstance(NominalInstanceType { class, .. }),
             )
             | (
-                Type::NominalInstance(instance),
+                instance @ Type::NominalInstance(NominalInstanceType { class, .. }),
                 Type::Callable(_) | Type::DataclassDecorator(_) | Type::DataclassTransformer(_),
-            ) if instance.class.is_final(db) => {
-                let member = self.member_lookup_with_policy(
+            ) if class.is_final(db) => instance
+                .member_lookup_with_policy(
                     db,
                     Name::new_static("__call__"),
                     MemberLookupPolicy::NO_INSTANCE_FALLBACK,
-                );
-                match member.symbol {
-                    // TODO: ideally this would check disjointness of the `__call__` signature and the callable signature
-                    Symbol::Type(ty, _) => !ty.is_assignable_to(db, CallableType::unknown(db)),
-                    Symbol::Unbound => true,
-                }
-            }
+                )
+                .symbol
+                .ignore_possibly_unbound()
+                .is_none_or(|dunder_call| {
+                    !dunder_call.is_assignable_to(db, CallableType::unknown(db))
+                }),
 
             (
                 Type::Callable(_) | Type::DataclassDecorator(_) | Type::DataclassTransformer(_),