heuristic completion for members of qualified expressions (PY-5629)

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

@@ -292,16 +292,16 @@ public class PyQualifiedReference extends PyReferenceImpl {
     final PyExpression qualifierElement = myElement.getQualifier();
     if (qualifierElement instanceof PyReferenceExpression) {
       PyReferenceExpression qualifier = (PyReferenceExpression)qualifierElement;
-      if (qualifier.getQualifier() == null) {
-        final String className = qualifier.getText();
+      final String className = qualifier.getReferencedName();
+      if (className != null) {
         Collection<PyClass> classes = PyClassNameIndexInsensitive.find(className, getElement().getProject());
         classes = filterByImports(classes, myElement.getContainingFile());
         if (classes.size() == 1) {
           final PyClassType classType = new PyClassType(classes.iterator().next(), false);
           return getTypeCompletionVariants(myElement, classType);
         }
-        return collectSeenMembers(qualifier.getText());
       }
+      return collectSeenMembers(qualifier.getText());
     }
     return ArrayUtil.EMPTY_OBJECT_ARRAY;
   }

python/testData/completion/classNameFromVarNameChained.after.py

@@ -0,0 +1,6 @@
+class Product:
+    def doStuff(self): pass
+
+class C:
+    def foo(self):
+        self.product.doStuff()

python/testData/completion/classNameFromVarNameChained.py

@@ -0,0 +1,6 @@
+class Product:
+    def doStuff(self): pass
+
+class C:
+    def foo(self):
+        self.product.doS<caret>

python/testSrc/com/jetbrains/python/PythonCompletionTest.java

@@ -126,6 +126,10 @@ public class PythonCompletionTest extends PyTestCase {
     doTest();
   }
 
+  public void testClassNameFromVarNameChained() {  // PY-5629
+    doTest();
+  }
+
   public void testPropertyType() {
     doTest();
   }