find usages considers a reference to be a usage if it resolves to an element that shadows our name or is shadowed by ours (PY-6241)

python/src/com/jetbrains/python/psi/impl/references/PyReferenceImpl.java

@@ -446,6 +446,12 @@ public class PyReferenceImpl implements PsiReferenceEx, PsiPolyVariantReference
             return true;
           }
 
+          // we shadow their name or they shadow ours (PY-6241)
+          if (resolveResult instanceof PsiNamedElement && resolveResult instanceof ScopeOwner && element instanceof ScopeOwner &&
+              ourScopeOwner == PsiTreeUtil.getParentOfType(resolveResult, ScopeOwner.class)) {
+            return true;
+          }
+
           if (!haveQualifiers(element) && ourScopeOwner != null && theirScopeOwner != null) {
             if (resolvesToSameGlobal(element, elementName, ourScopeOwner, theirScopeOwner, resolveResult)) return true;
           }

python/testData/findUsages/NameShadowing.py

@@ -0,0 +1,16 @@
+class C(object):
+    def __init__(self):
+        self._x = None
+
+    @property
+    def <caret>x(self):
+        """I'm the 'x' property."""
+        return self._x
+
+    @x.setter
+    def x(self, value):
+        self._x = value
+
+    @x.deleter
+    def x(self):
+        del self._x

python/testSrc/com/jetbrains/python/PyFindUsagesTest.java

@@ -127,6 +127,11 @@ public class PyFindUsagesTest extends PyTestCase {
     }
   }
 
+  public void testNameShadowing() {  // PY-6241
+    final Collection<UsageInfo> usages = myFixture.testFindUsages("findUsages/NameShadowing.py");
+    assertEquals(2, usages.size());
+  }
+
   private Collection<UsageInfo> findMultiFileUsages(String filename) {
     final String testName = getTestName(false);
     myFixture.copyDirectoryToProject("findUsages/" + testName, "");