Fixed a bug that led to a false negative when a subclass overrides a …

…parent class with an overloaded method in an incompatible manner. This addresses #6382. (#6396)
microsoft · Nov 9, 2023 · de7d732 · de7d732
1 parent dbd9976
commit de7d732
Show file tree

Hide file tree

Showing 3 changed files with 30 additions and 2 deletions.
diff --git a/packages/pyright-internal/src/analyzer/typeEvaluator.ts b/packages/pyright-internal/src/analyzer/typeEvaluator.ts
@@ -24878,7 +24878,7 @@ export function createTypeEvaluator(importLookup: ImportLookup, evaluatorOptions
             }
 
             if (matchIndex < 0) {
-                continue;
+                break;
             }
 
             if (matchIndex < previousMatchIndex) {

diff --git a/packages/pyright-internal/src/tests/samples/methodOverride6.py b/packages/pyright-internal/src/tests/samples/methodOverride6.py
@@ -263,3 +263,31 @@ def function(self: Parent4[int], a: int) -> float:
 
     def function(self, a: int | None = None) -> float:
         return 0.0
+
+
+class Parent5:
+    @overload
+    def m1(self, x: int) -> int:
+        ...
+
+    @overload
+    def m1(self, x: str) -> str:
+        ...
+
+    def m1(self, x: int | str) -> int | str:
+        ...
+
+
+class Parent5_1(Parent5):
+    @overload
+    def m1(self, x: bytes) -> bytes:
+        ...
+
+    @overload
+    def m1(self, x: str) -> str:
+        ...
+
+    # This should generate an error because the overloads are
+    # incompatible
+    def m1(self, x: bytes | str) -> bytes | str:
+        ...
diff --git a/packages/pyright-internal/src/tests/typeEvaluator3.test.ts b/packages/pyright-internal/src/tests/typeEvaluator3.test.ts
@@ -877,7 +877,7 @@ test('MethodOverride6', () => {
 
     configOptions.diagnosticRuleSet.reportIncompatibleMethodOverride = 'error';
     const analysisResults2 = TestUtils.typeAnalyzeSampleFiles(['methodOverride6.py'], configOptions);
-    TestUtils.validateResults(analysisResults2, 2);
+    TestUtils.validateResults(analysisResults2, 3);
 });
 
 test('Enum1', () => {
-Original file line number
+Diff line change
@@ Expand Up @@
                 }
                 if (matchIndex < 0) {
-                    continue;
+                    break;
                 }
                 if (matchIndex < previousMatchIndex) {
@@ Expand Down @@