[ty] Avoid accessing class literal with incorrect AST (#18670)

crates/ty_python_semantic/src/types/class.rs

@@ -2021,8 +2021,8 @@ impl<'db> ClassLiteral<'db> {
     /// Returns a [`Span`] with the range of the class's header.
     ///
     /// See [`Self::header_range`] for more details.
-    pub(super) fn header_span(self, db: &'db dyn Db, module: &ParsedModuleRef) -> Span {
+    pub(super) fn header_span(self, db: &'db dyn Db) -> Span {
-        Span::from(self.file(db)).with_range(self.header_range(db, module))
+        Span::from(self.file(db)).with_range(self.header_range(db))
     }
 
     /// Returns the range of the class's "header": the class name
@@ -2032,9 +2032,10 @@ impl<'db> ClassLiteral<'db> {
     /// class Foo(Bar, metaclass=Baz): ...
     ///       ^^^^^^^^^^^^^^^^^^^^^^^
     /// ```
-    pub(super) fn header_range(self, db: &'db dyn Db, module: &ParsedModuleRef) -> TextRange {
+    pub(super) fn header_range(self, db: &'db dyn Db) -> TextRange {
         let class_scope = self.body_scope(db);
-        let class_node = class_scope.node(db).expect_class(module);
+        let module = parsed_module(db.upcast(), class_scope.file(db)).load(db.upcast());
+        let class_node = class_scope.node(db).expect_class(&module);
         let class_name = &class_node.name;
         TextRange::new(
             class_name.start(),

crates/ty_python_semantic/src/types/diagnostic.rs

@@ -1788,7 +1788,7 @@ pub(super) fn report_implicit_return_type(
             or `typing_extensions.Protocol` are considered protocol classes",
         );
         sub_diagnostic.annotate(
-            Annotation::primary(class.header_span(db, context.module())).message(format_args!(
+            Annotation::primary(class.header_span(db)).message(format_args!(
                 "`Protocol` not present in `{class}`'s immediate bases",
                 class = class.name(db)
             )),
@@ -1908,7 +1908,7 @@ pub(crate) fn report_bad_argument_to_get_protocol_members(
             class.name(db)
         ),
     );
-    class_def_diagnostic.annotate(Annotation::primary(class.header_span(db, context.module())));
+    class_def_diagnostic.annotate(Annotation::primary(class.header_span(db)));
     diagnostic.sub(class_def_diagnostic);
 
     diagnostic.info(
@@ -1971,7 +1971,7 @@ pub(crate) fn report_runtime_check_against_non_runtime_checkable_protocol(
         ),
     );
     class_def_diagnostic.annotate(
-        Annotation::primary(protocol.header_span(db, context.module()))
+        Annotation::primary(protocol.header_span(db))
             .message(format_args!("`{class_name}` declared here")),
     );
     diagnostic.sub(class_def_diagnostic);
@@ -2002,7 +2002,7 @@ pub(crate) fn report_attempted_protocol_instantiation(
         format_args!("Protocol classes cannot be instantiated"),
     );
     class_def_diagnostic.annotate(
-        Annotation::primary(protocol.header_span(db, context.module()))
+        Annotation::primary(protocol.header_span(db))
             .message(format_args!("`{class_name}` declared as a protocol here")),
     );
     diagnostic.sub(class_def_diagnostic);
@@ -2016,9 +2016,7 @@ pub(crate) fn report_duplicate_bases(
 ) {
     let db = context.db();
 
-    let Some(builder) =
+    let Some(builder) = context.report_lint(&DUPLICATE_BASE, class.header_range(db)) else {
-        context.report_lint(&DUPLICATE_BASE, class.header_range(db, context.module()))
-    else {
         return;
     };