Don't display the implicit typing.Self type

crates/ty_python_semantic/resources/mdtest/annotations/self.md

@@ -42,7 +42,6 @@ class Shape:
 
 reveal_type(Shape().nested_type())  # revealed: list[Shape]
 reveal_type(Shape().nested_func())  # revealed: Shape
-reveal_type(Shape().implicit_self())  # revealed: Shape
 
 class Circle(Shape):
     def set_scale(self: Self, scale: float) -> Self:
@@ -56,6 +55,37 @@ class Outer:
             return self
 ```
 
+## Detection of Self
+
+The first argument in method is assumed to have type `typing.Self`.
+
+```toml
+[environment]
+python-version = "3.11"
+```
+
+```py
+from typing import Self
+
+class A:
+    def implicit_self(self) -> Self:
+        # TODO: first argument in a method should be considered as "typing.Self"
+        reveal_type(self)  # revealed: Unknown
+        return self
+
+    def foo(self) -> int:
+        def first_arg_is_not_self(a: int) -> int:
+            return a
+        return first_arg_is_not_self(1)
+    # TODO: Make sure cls is not considered as "typing.Self". Don't know how to test this
+    @classmethod
+    def bar(cls) -> int:
+        return 1
+
+reveal_type(A().implicit_self())  # revealed: A
+reveal_type(A.implicit_self)  # revealed: def implicit_self(self) -> Self
+```
+
 ## typing_extensions
 
 ```toml

crates/ty_python_semantic/resources/mdtest/call/methods.md

@@ -69,7 +69,9 @@ reveal_type(bound_method(1))  # revealed: str
 When we call the function object itself, we need to pass the `instance` explicitly:
 
 ```py
-C.f(1)  # error: [missing-argument]
+# error: [invalid-argument-type]
+# error: [missing-argument]
+C.f(1)
 
 reveal_type(C.f(C(), 1))  # revealed: str
 ```

crates/ty_python_semantic/src/types/display.rs

@@ -1150,12 +1150,14 @@ impl Display for DisplayParameter<'_> {
         if let Some(name) = self.param.display_name() {
             f.write_str(&name)?;
             if let Some(annotated_type) = self.param.annotated_type() {
+                if !self.param.type_inffered() {
                     write!(
                         f,
                         ": {}",
                         annotated_type.display_with(self.db, self.settings)
                     )?;
                 }
+            }
             // Default value can only be specified if `name` is given.
             if let Some(default_ty) = self.param.default_type() {
                 if self.param.annotated_type().is_some() {
@@ -1167,8 +1169,10 @@ impl Display for DisplayParameter<'_> {
         } else if let Some(ty) = self.param.annotated_type() {
             // This case is specifically for the `Callable` signature where name and default value
             // cannot be provided.
+            if !self.param.type_inffered() {
                 ty.display_with(self.db, self.settings).fmt(f)?;
             }
+        }
         Ok(())
     }
 }

crates/ty_python_semantic/src/types/signatures.rs

@@ -17,7 +17,7 @@ use smallvec::{SmallVec, smallvec_inline};
 
 use super::{
     DynamicType, FunctionDecorators, KnownInstanceType, Type, definition_expression_type,
-    infer_definition_types, nearest_enclosing_class, semantic_index,
+    infer_definition_types, semantic_index,
 };
 use super::{DynamicType, Type, TypeVarVariance, definition_expression_type};
 use super::{DynamicType, Type, definition_expression_type};
@@ -1179,12 +1179,14 @@ impl<'db> Parameters<'db> {
         let function_is_method = if matches!(definition.kind(db), DefinitionKind::Function(_)) {
             let scope = definition.scope(db);
             let index = semantic_index(db, scope.file(db));
-            nearest_enclosing_class(db, index, scope).is_some()
+            let current_scope = index.scope(scope.file_scope_id(db));
+            // class_context_of_current_method(db, index, scope).is_some()
+            current_scope.kind().is_class()
         } else {
             false
         };
         let classmethod = if let DefinitionKind::Function(f) = definition.kind(db) {
-            if f.name.id() == "__new__" {
+            if matches!(f.name.id().as_str(), "__new__" | "__class_getitem__") {
                 true
             } else {
                 let result = infer_definition_types(db, definition);
@@ -1198,11 +1200,12 @@ impl<'db> Parameters<'db> {
         } else {
             false
         };
+
         let positional_or_keyword = args.iter().enumerate().map(|(index, arg)| {
             if index == 0
                 && function_is_method
                 && arg.parameter.annotation().is_none()
-                // TODO: Handle type of cls
+                // TODO: Handle case when cls is not annotated
                 && !classmethod
             {
                 let implicit_annotation = Type::KnownInstance(KnownInstanceType::TypingSelf)
@@ -1210,6 +1213,7 @@ impl<'db> Parameters<'db> {
                     .unwrap();
                 Parameter {
                     annotated_type: Some(implicit_annotation),
+                    type_inffered: true,
                     kind: ParameterKind::PositionalOrKeyword {
                         name: arg.parameter.name.id.clone(),
                         default_type: default_type(arg),
@@ -1383,6 +1387,10 @@ pub(crate) struct Parameter<'db> {
     /// Annotated type of the parameter.
     annotated_type: Option<Type<'db>>,
 
+    /// If the type of parameter was inferred e.g. the first argument of a method has type
+    /// `typing.Self`.
+    type_inffered: bool,
+
     kind: ParameterKind<'db>,
     pub(crate) form: ParameterForm,
 }
@@ -1391,6 +1399,7 @@ impl<'db> Parameter<'db> {
     pub(crate) fn positional_only(name: Option<Name>) -> Self {
         Self {
             annotated_type: None,
+            type_inffered: false,
             kind: ParameterKind::PositionalOnly {
                 name,
                 default_type: None,
@@ -1402,6 +1411,7 @@ impl<'db> Parameter<'db> {
     pub(crate) fn positional_or_keyword(name: Name) -> Self {
         Self {
             annotated_type: None,
+            type_inffered: false,
             kind: ParameterKind::PositionalOrKeyword {
                 name,
                 default_type: None,
@@ -1413,6 +1423,7 @@ impl<'db> Parameter<'db> {
     pub(crate) fn variadic(name: Name) -> Self {
         Self {
             annotated_type: None,
+            type_inffered: false,
             kind: ParameterKind::Variadic { name },
             form: ParameterForm::Value,
         }
@@ -1421,6 +1432,7 @@ impl<'db> Parameter<'db> {
     pub(crate) fn keyword_only(name: Name) -> Self {
         Self {
             annotated_type: None,
+            type_inffered: false,
             kind: ParameterKind::KeywordOnly {
                 name,
                 default_type: None,
@@ -1432,6 +1444,7 @@ impl<'db> Parameter<'db> {
     pub(crate) fn keyword_variadic(name: Name) -> Self {
         Self {
             annotated_type: None,
+            type_inffered: false,
             kind: ParameterKind::KeywordVariadic { name },
             form: ParameterForm::Value,
         }
@@ -1470,6 +1483,7 @@ impl<'db> Parameter<'db> {
                 .annotated_type
                 .map(|ty| ty.apply_type_mapping_impl(db, type_mapping, visitor)),
             kind: self.kind.apply_type_mapping_impl(db, type_mapping, visitor),
+            type_inffered: self.type_inffered,
             form: self.form,
         }
     }
@@ -1485,6 +1499,7 @@ impl<'db> Parameter<'db> {
     ) -> Self {
         let Parameter {
             annotated_type,
+            type_inffered,
             kind,
             form,
         } = self;
@@ -1527,7 +1542,14 @@ impl<'db> Parameter<'db> {
         };
 
         Self {
+<<<<<<< HEAD
             annotated_type: Some(annotated_type),
+||||||| parent of 63531eab6 (Don't display the implicit typing.Self type)
+            annotated_type,
+=======
+            annotated_type,
+            type_inffered: *type_inffered,
+>>>>>>> 63531eab6 (Don't display the implicit typing.Self type)
             kind,
             form: *form,
         }
@@ -1540,12 +1562,23 @@ impl<'db> Parameter<'db> {
         kind: ParameterKind<'db>,
     ) -> Self {
         Self {
+<<<<<<< HEAD
             annotated_type: parameter.annotation().map(|annotation| {
                 definition_expression_type(db, definition, annotation).apply_type_mapping(
                     db,
                     &TypeMapping::MarkTypeVarsInferable(BindingContext::Definition(definition)),
                 )
             }),
+||||||| parent of 63531eab6 (Don't display the implicit typing.Self type)
+            annotated_type: parameter
+                .annotation()
+                .map(|annotation| definition_expression_type(db, definition, annotation)),
+=======
+            annotated_type: parameter
+                .annotation()
+                .map(|annotation| definition_expression_type(db, definition, annotation)),
+            type_inffered: false,
+>>>>>>> 63531eab6 (Don't display the implicit typing.Self type)
             kind,
             form: ParameterForm::Value,
         }
@@ -1602,6 +1635,11 @@ impl<'db> Parameter<'db> {
         &self.kind
     }
 
+    /// Whether the type of the parameter was inferred.
+    pub(crate) fn type_inffered(&self) -> bool {
+        self.type_inffered
+    }
+
     /// Name of the parameter (if it has one).
     pub(crate) fn name(&self) -> Option<&ast::name::Name> {
         match &self.kind {