From aedde231e738c4512b6ed1c88d5f4f18d2e07be3 Mon Sep 17 00:00:00 2001
From: Semyon Proshev <Semyon.Proshev@jetbrains.com>
Date: Fri, 9 Nov 2018 18:51:52 +0300
Subject: [PATCH] Filter out fake elements from typeshed builtins (PY-22508)

---
 python/src/com/jetbrains/python/pyi/PyiFile.kt              | 5 ++++-
 .../inspections/PyShadowingBuiltinsInspection/test.py       | 6 ++++++
 .../testData/intentions/convertLambdaToFunction2_after.py   | 4 ++--
 .../inspections/PyUnresolvedReferencesInspectionTest.java   | 6 ++++++
 4 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/python/src/com/jetbrains/python/pyi/PyiFile.kt b/python/src/com/jetbrains/python/pyi/PyiFile.kt
index 63c4ce4f444a..fb19fa3de7a3 100644
--- a/python/src/com/jetbrains/python/pyi/PyiFile.kt
+++ b/python/src/com/jetbrains/python/pyi/PyiFile.kt
@@ -19,6 +19,7 @@ import com.intellij.psi.FileViewProvider
 import com.jetbrains.python.PythonFileType
 import com.jetbrains.python.psi.LanguageLevel
 import com.jetbrains.python.psi.PyImportElement
+import com.jetbrains.python.psi.impl.PyBuiltinCache
 import com.jetbrains.python.psi.impl.PyFileImpl
 import com.jetbrains.python.psi.resolve.ImportedResolveResult
 import com.jetbrains.python.psi.resolve.RatedResolveResult
@@ -29,11 +30,13 @@ import com.jetbrains.python.psi.resolve.RatedResolveResult
 class PyiFile(viewProvider: FileViewProvider) : PyFileImpl(viewProvider, PyiLanguageDialect.getInstance()) {
   override fun getFileType(): PythonFileType = PyiFileType.INSTANCE
 
-  override fun toString(): String = "PyiFile:" + name
+  override fun toString(): String = "PyiFile:$name"
 
   override fun getLanguageLevel(): LanguageLevel = LanguageLevel.PYTHON37
 
   override fun multiResolveName(name: String, exported: Boolean): List<RatedResolveResult> {
+    if (name == "function" && PyBuiltinCache.getInstance(this).builtinsFile == this) return emptyList()
+
     val baseResults = super.multiResolveName(name, exported)
     return if (exported)
       baseResults
diff --git a/python/testData/inspections/PyShadowingBuiltinsInspection/test.py b/python/testData/inspections/PyShadowingBuiltinsInspection/test.py
index 4951bf1fdf50..422ac3e7397a 100644
--- a/python/testData/inspections/PyShadowingBuiltinsInspection/test.py
+++ b/python/testData/inspections/PyShadowingBuiltinsInspection/test.py
@@ -48,3 +48,9 @@ def test_builtin_qualified_name():
 def test_builtin_class_attribute():
     class C:
         id = 1
+
+
+# PY-22508
+def test_fakes_from_typeshed():
+    function = 10
+    module = 10
\ No newline at end of file
diff --git a/python/testData/intentions/convertLambdaToFunction2_after.py b/python/testData/intentions/convertLambdaToFunction2_after.py
index ac27ce8c04aa..113f460f0a8c 100644
--- a/python/testData/intentions/convertLambdaToFunction2_after.py
+++ b/python/testData/intentions/convertLambdaToFunction2_after.py
@@ -1,5 +1,5 @@
 def transform():
-  def function1(x):
+  def function(x):
       return x + 5
 
-  return function1
\ No newline at end of file
+  return function
\ No newline at end of file
diff --git a/python/testSrc/com/jetbrains/python/inspections/PyUnresolvedReferencesInspectionTest.java b/python/testSrc/com/jetbrains/python/inspections/PyUnresolvedReferencesInspectionTest.java
index c69af8c114a1..701e1947820e 100644
--- a/python/testSrc/com/jetbrains/python/inspections/PyUnresolvedReferencesInspectionTest.java
+++ b/python/testSrc/com/jetbrains/python/inspections/PyUnresolvedReferencesInspectionTest.java
@@ -764,6 +764,12 @@ public class PyUnresolvedReferencesInspectionTest extends PyInspectionTestCase {
     doTest();
   }
 
+  // PY-22508
+  public void testFakesFromTypeshed() {
+    doTestByText("print(<error descr=\"Unresolved reference 'function'\">function</error>)\n" +
+                 "print(<error descr=\"Unresolved reference 'module'\">module</error>)");
+  }
+
   @NotNull
   @Override
   protected Class<? extends PyInspection> getInspectionClass() {