Fixed a bug that results in a spurious error when specializing an old…

…-style generic type alias whose type is defined as a new-style type alias that has multiple type parameters, only some of which are used in its type definition. This addresses #9273.
microsoft · Oct 20, 2024 · 0f3a561 · 0f3a561
1 parent 9b0d2e0
commit 0f3a561
Showing 1 changed file with 15 additions and 5 deletions.
diff --git a/packages/pyright-internal/src/analyzer/typeUtils.ts b/packages/pyright-internal/src/analyzer/typeUtils.ts
@@ -2004,14 +2004,24 @@ export function getTypeVarArgsRecursive(type: Type, recursionCount = 0): TypeVar
     recursionCount++;
 
     const aliasInfo = type.props?.typeAliasInfo;
-    if (aliasInfo?.typeArgs) {
+    if (aliasInfo) {
         const combinedList: TypeVarType[] = [];
 
-        aliasInfo?.typeArgs.forEach((typeArg) => {
-            addTypeVarsToListIfUnique(combinedList, getTypeVarArgsRecursive(typeArg, recursionCount));
-        });
+        if (aliasInfo.typeArgs) {
+            aliasInfo?.typeArgs.forEach((typeArg) => {
+                addTypeVarsToListIfUnique(combinedList, getTypeVarArgsRecursive(typeArg, recursionCount));
+            });
 
-        return combinedList;
+            return combinedList;
+        }
+
+        if (aliasInfo.shared.typeParams) {
+            aliasInfo.shared.typeParams.forEach((typeParam) => {
+                addTypeVarsToListIfUnique(combinedList, [typeParam]);
+            });
+
+            return combinedList;
+        }
     }
 
     if (isTypeVar(type)) {