Don't special-case class instances in unary expression inference

crates/red_knot_python_semantic/resources/mdtest/unary/custom.md

@@ -0,0 +1,165 @@
+# Custom unary operations
+
+## Class instances
+
+```py
+class Yes:
+    def __pos__(self) -> bool:
+        return False
+
+    def __neg__(self) -> str:
+        return "negative"
+
+    def __invert__(self) -> int:
+        return 17
+
+class Sub(Yes): ...
+class No: ...
+
+reveal_type(+Yes())  # revealed: bool
+reveal_type(-Yes())  # revealed: str
+reveal_type(~Yes())  # revealed: int
+
+reveal_type(+Sub())  # revealed: bool
+reveal_type(-Sub())  # revealed: str
+reveal_type(~Sub())  # revealed: int
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `No`"
+reveal_type(+No())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `No`"
+reveal_type(-No())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `No`"
+reveal_type(~No())  # revealed: Unknown
+```
+
+## Classes
+
+```py
+class Yes:
+    def __pos__(self) -> bool:
+        return False
+
+    def __neg__(self) -> str:
+        return "negative"
+
+    def __invert__(self) -> int:
+        return 17
+
+class Sub(Yes): ...
+class No: ...
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `Literal[Yes]`"
+reveal_type(+Yes)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `Literal[Yes]`"
+reveal_type(-Yes)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `Literal[Yes]`"
+reveal_type(~Yes)  # revealed: Unknown
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `Literal[Sub]`"
+reveal_type(+Sub)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `Literal[Sub]`"
+reveal_type(-Sub)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `Literal[Sub]`"
+reveal_type(~Sub)  # revealed: Unknown
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `Literal[No]`"
+reveal_type(+No)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `Literal[No]`"
+reveal_type(-No)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `Literal[No]`"
+reveal_type(~No)  # revealed: Unknown
+```
+
+## Function literals
+
+```py
+def f():
+    pass
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `Literal[f]`"
+reveal_type(+f)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `Literal[f]`"
+reveal_type(-f)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `Literal[f]`"
+reveal_type(~f)  # revealed: Unknown
+```
+
+## Subclass
+
+```py
+class Yes:
+    def __pos__(self) -> bool:
+        return False
+
+    def __neg__(self) -> str:
+        return "negative"
+
+    def __invert__(self) -> int:
+        return 17
+
+class Sub(Yes): ...
+class No: ...
+
+def yes() -> type[Yes]:
+    return Yes
+
+def sub() -> type[Sub]:
+    return Sub
+
+def no() -> type[No]:
+    return No
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `type[Yes]`"
+reveal_type(+yes())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `type[Yes]`"
+reveal_type(-yes())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `type[Yes]`"
+reveal_type(~yes())  # revealed: Unknown
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `type[Sub]`"
+reveal_type(+sub())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `type[Sub]`"
+reveal_type(-sub())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `type[Sub]`"
+reveal_type(~sub())  # revealed: Unknown
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `type[No]`"
+reveal_type(+no())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `type[No]`"
+reveal_type(-no())  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `type[No]`"
+reveal_type(~no())  # revealed: Unknown
+```
+
+## Metaclass
+
+```py
+class Meta(type):
+    def __pos__(self) -> bool:
+        return False
+
+    def __neg__(self) -> str:
+        return "negative"
+
+    def __invert__(self) -> int:
+        return 17
+
+class Yes(metaclass=Meta): ...
+class Sub(Yes): ...
+class No: ...
+
+reveal_type(+Yes)  # revealed: bool
+reveal_type(-Yes)  # revealed: str
+reveal_type(~Yes)  # revealed: int
+
+reveal_type(+Sub)  # revealed: bool
+reveal_type(-Sub)  # revealed: str
+reveal_type(~Sub)  # revealed: int
+
+# error: [unsupported-operator] "Unary operator `+` is unsupported for type `Literal[No]`"
+reveal_type(+No)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `-` is unsupported for type `Literal[No]`"
+reveal_type(-No)  # revealed: Unknown
+# error: [unsupported-operator] "Unary operator `~` is unsupported for type `Literal[No]`"
+reveal_type(~No)  # revealed: Unknown
+```

crates/red_knot_python_semantic/src/types/infer.rs

@@ -3193,10 +3193,7 @@ impl<'db> TypeInferenceBuilder<'db> {
             (UnaryOp::Not, ty) => ty.bool(self.db()).negate().into_type(self.db()),
             (_, Type::Any) => Type::Any,
             (_, Type::Unknown) => Type::Unknown,
-            (
-                op @ (UnaryOp::UAdd | UnaryOp::USub | UnaryOp::Invert),
-                Type::Instance(InstanceType { class }),
-            ) => {
+            (op @ (UnaryOp::UAdd | UnaryOp::USub | UnaryOp::Invert), _) => {
                 let unary_dunder_method = match op {
                     UnaryOp::Invert => "__invert__",
                     UnaryOp::UAdd => "__pos__",
@@ -3206,9 +3203,8 @@ impl<'db> TypeInferenceBuilder<'db> {
                     }
                 };
 
-                if let Symbol::Type(class_member, _) =
-                    class.class_member(self.db(), unary_dunder_method)
-                {
+                let meta = operand_type.to_meta_type(self.db());
+                if let Symbol::Type(class_member, _) = meta.member(self.db(), unary_dunder_method) {
                     let call = class_member.call(self.db(), &[operand_type]);
 
                     match call.return_ty_result(&self.context, AnyNodeRef::ExprUnaryOp(unary)) {
@@ -3238,7 +3234,6 @@ impl<'db> TypeInferenceBuilder<'db> {
                     Type::Unknown
                 }
             }
-            _ => todo_type!(), // TODO other unary op types
         }
     }