From b4c21038f3685f6be76ae0228b33f91c536f5d8e Mon Sep 17 00:00:00 2001
From: Semyon Proshev <Semyon.Proshev@jetbrains.com>
Date: Tue, 13 Mar 2018 17:28:51 +0300
Subject: [PATCH] Don't inspect protocol attributes inherited from
 non-protocols (PY-28720)

---
 .../python/codeInsight/typing/PyProtocols.kt  | 11 ++++-
 .../PyTypeCheckerInspectionTest.java          | 43 +++++++++++++++++++
 2 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt b/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt
index ed9df849e69a..dee3ee619344 100644
--- a/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt
+++ b/python/src/com/jetbrains/python/codeInsight/typing/PyProtocols.kt
@@ -1,11 +1,11 @@
 // Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.jetbrains.python.codeInsight.typing
 
-import com.intellij.openapi.util.io.FileUtil
 import com.jetbrains.python.codeInsight.typing.PyTypingTypeProvider.PROTOCOL
 import com.jetbrains.python.codeInsight.typing.PyTypingTypeProvider.PROTOCOL_EXT
 import com.jetbrains.python.psi.AccessDirection
 import com.jetbrains.python.psi.PyClass
+import com.jetbrains.python.psi.PyPossibleClassMember
 import com.jetbrains.python.psi.PyTypedElement
 import com.jetbrains.python.psi.resolve.PyResolveContext
 import com.jetbrains.python.psi.resolve.RatedResolveResult
@@ -35,7 +35,14 @@ fun inspectProtocolSubclass(protocol: PyClassType, subclass: PyClassType, contex
 
   protocol.toInstance().visitMembers(
     { e ->
-      if (e is PyTypedElement && FileUtil.getNameWithoutExtension(e.containingFile.name) != "typing_extensions") {
+      if (e is PyTypedElement) {
+        if (e is PyPossibleClassMember) {
+          val cls = e.containingClass
+          if (cls != null && !isProtocol(cls, context)) {
+            return@visitMembers true
+          }
+        }
+
         val name = e.name ?: return@visitMembers true
         val resolveResults = subclassAsInstance.resolveMember(name, null, AccessDirection.READ, resolveContext)
 
diff --git a/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java b/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java
index 87c260069fc1..e2d22ab1d7cf 100644
--- a/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java
+++ b/python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java
@@ -521,6 +521,49 @@ public class PyTypeCheckerInspectionTest extends PyInspectionTestCase {
     runWithLanguageLevel(LanguageLevel.PYTHON35, this::doTest);
   }
 
+  // PY-28720
+  public void testOverriddenBuiltinMethodAgainstTypingProtocol() {
+    runWithLanguageLevel(
+      LanguageLevel.PYTHON35,
+      () ->
+        doTestByText("import typing\n" +
+                     "class Proto(typing.Protocol):\n" +
+                     "    def function(self) -> None:\n" +
+                     "        pass\n" +
+                     "class Cls:\n" +
+                     "    def __eq__(self, other) -> 'Cls':\n" +
+                     "        pass\n" +
+                     "    def function(self) -> None:\n" +
+                     "        pass\n" +
+                     "def method(p: Proto):\n" +
+                     "    pass\n" +
+                     "method(Cls())")
+    );
+  }
+
+  // PY-28720
+  public void testAgainstInvalidProtocol() {
+    runWithLanguageLevel(
+      LanguageLevel.PYTHON34,
+      () ->
+        doTestByText(
+          "from typing import Any, Protocol\n" +
+          "class B:\n" +
+          "    def foo(self):\n" +
+          "        ...\n" +
+          "class C(B, Protocol):\n" +
+          "    def bar(self):\n" +
+          "        ...\n" +
+          "class Bar:\n" +
+          "    def bar(self):\n" +
+          "        ...\n" +
+          "def f(x: C) -> Any:\n" +
+          "    ...\n" +
+          "f(Bar())"
+        )
+    );
+  }
+
   // PY-23161
   public void testGenericWithTypeVarBounds() {
     runWithLanguageLevel(LanguageLevel.PYTHON35, this::doTest);