Don't crash on invalid property definition

python · JukkaL · Nov 15, 2019 · Nov 5, 2019 · Nov 5, 2019 · Nov 5, 2019
commit 97f2bf49dbb5b4a3bf69f2ccb92676ca44bed76c
diff --git a/mypy/semanal.py b/mypy/semanal.py
@@ -865,19 +865,25 @@ def analyze_property_with_multi_part_definition(self, defn: OverloadedFuncDef) -
         defn.is_property = True
         items = defn.items
         first_item = cast(Decorator, defn.items[0])
-        for item in items[1:]:
-            if isinstance(item, Decorator) and len(item.decorators) == 1:
-                node = item.decorators[0]
-                if isinstance(node, MemberExpr):
-                    if node.name == 'setter':
-                        # The first item represents the entire property.
-                        first_item.var.is_settable_property = True
-                        # Get abstractness from the original definition.
-                        item.func.is_abstract = first_item.func.is_abstract
-            else:
-                self.fail("Decorated property not supported", item)
+        deleted_items = []
+        for i, item in enumerate(items[1:]):
             if isinstance(item, Decorator):
+                if len(item.decorators) == 1:
+                    node = item.decorators[0]
+                    if isinstance(node, MemberExpr):
+                        if node.name == 'setter':
+                            # The first item represents the entire property.
+                            first_item.var.is_settable_property = True
+                            # Get abstractness from the original definition.
+                            item.func.is_abstract = first_item.func.is_abstract
+                else:
+                    self.fail("Decorated property not supported", item)
                 item.func.accept(self)
+            else:
+                self.fail('Unexpected definition for property "{}"'.format(first_item.func.name()), item)
+                deleted_items.append(i + 1)
+        for i in reversed(deleted_items):
+            del items[i]
 
     def add_function_to_symbol_table(self, func: Union[FuncDef, OverloadedFuncDef]) -> None:
         if self.is_class_scope():

diff --git a/test-data/unit/check-classes.test b/test-data/unit/check-classes.test
@@ -6545,3 +6545,12 @@ class C3(Generic[TypeT1]):
         return 0
 
 [builtins fixtures/isinstancelist.pyi]
+
+[case testPropertyWithExtraMethod]
+class A:
+    @property
+    def x(self): ...
+    @x.setter
+    def x(self, value) -> None: ...
+    def x(self) -> None: ...  # E: Unexpected definition for property "x"
+[builtins fixtures/property.pyi]