Merge 35b633c into 6468a35

charliermarsh · web-flow · commit 88825983c2b1 · 2026-03-31T17:04:17.000Z
diff --git a/crates/ty_python_semantic/resources/mdtest/typed_dict.md b/crates/ty_python_semantic/resources/mdtest/typed_dict.md
@@ -2529,12 +2529,22 @@ Movie2 = TypedDict("Movie2", name=str, year=int)
 ```py
 from typing_extensions import TypedDict
 
-# error: [invalid-argument-type] "Invalid argument to parameter `typename` of `TypedDict()`"
+# error: [invalid-argument-type] "TypedDict name must match the variable it is assigned to: Expected "Bad1", got variable of type `Literal[123]`"
 Bad1 = TypedDict(123, {"name": str})
 
-# error: [invalid-argument-type] "The name of a `TypedDict` (`WrongName`) must match the name of the variable it is assigned to (`BadTypedDict3`)"
+# error: [invalid-argument-type] "TypedDict name must match the variable it is assigned to: Expected "BadTypedDict3", got "WrongName""
 BadTypedDict3 = TypedDict("WrongName", {"name": str})
 
+def f(x: str) -> None:
+    # error: [invalid-argument-type] "TypedDict name must match the variable it is assigned to: Expected "Y", got variable of type `str`"
+    Y = TypedDict(x, {})
+
+def g(x: str) -> None:
+    TypedDict(x, {})  # fine
+
+name = "GoodTypedDict"
+GoodTypedDict = TypedDict(name, {"name": str})
+
 # error: [invalid-argument-type] "Expected a dict literal for parameter `fields` of `TypedDict()`"
 Bad2 = TypedDict("Bad2", "not a dict")
 
diff --git a/crates/ty_python_semantic/src/types/infer/builder/typed_dict.rs b/crates/ty_python_semantic/src/types/infer/builder/typed_dict.rs
@@ -158,34 +158,40 @@ impl<'db> TypeInferenceBuilder<'db, '_> {
             );
         }
 
-        let name = if let Some(literal) = name_type.as_string_literal() {
-            let name = literal.value(db);
-
-            if let Some(assigned_name) = definition.and_then(|definition| definition.name(db))
-                && name != assigned_name
-                && let Some(builder) = self.context.report_lint(&INVALID_ARGUMENT_TYPE, name_arg)
-            {
-                builder.into_diagnostic(format_args!(
-                    "The name of a `TypedDict` (`{name}`) must match \
-                    the name of the variable it is assigned to (`{assigned_name}`)"
-                ));
-            }
-
-            Name::new(name)
-        } else {
-            if !name_type.is_assignable_to(db, KnownClass::Str.to_instance(db))
-                && let Some(builder) = self.context.report_lint(&INVALID_ARGUMENT_TYPE, name_arg)
-            {
-                let mut diagnostic = builder.into_diagnostic(format_args!(
-                    "Invalid argument to parameter `typename` of `TypedDict()`"
+        let name = name_type
+            .as_string_literal()
+            .map(|literal| Name::new(literal.value(db)));
+
+        if let Some(definition) = definition
+            && let Some(assigned_name) = definition.name(db)
+            && Some(assigned_name.as_str()) != name.as_deref()
+            && let Some(builder) = self.context.report_lint(&INVALID_ARGUMENT_TYPE, name_arg)
+        {
+            let mut diagnostic =
+                builder.into_diagnostic("TypedDict name must match the variable it is assigned to");
+            if let Some(name) = name.as_deref() {
+                diagnostic.set_primary_message(format_args!(
+                    "Expected \"{assigned_name}\", got \"{name}\""
                 ));
+            } else {
                 diagnostic.set_primary_message(format_args!(
-                    "Expected `str`, found `{}`",
+                    "Expected \"{assigned_name}\", got variable of type `{}`",
                     name_type.display(db)
                 ));
             }
-            Name::new_static("<unknown>")
-        };
+        } else if !name_type.is_assignable_to(db, KnownClass::Str.to_instance(db))
+            && let Some(builder) = self.context.report_lint(&INVALID_ARGUMENT_TYPE, name_arg)
+        {
+            let mut diagnostic = builder.into_diagnostic(format_args!(
+                "Invalid argument to parameter `typename` of `TypedDict()`"
+            ));
+            diagnostic.set_primary_message(format_args!(
+                "Expected `str`, found `{}`",
+                name_type.display(db)
+            ));
+        }
+
+        let name = name.unwrap_or_else(|| Name::new_static("<unknown>"));
 
         if let Some(definition) = definition {
             self.deferred.insert(definition);
