generate 'return' before super method call in Override Methods if appropriate (PY-1537)

python/src/com/jetbrains/python/codeInsight/override/PyOverrideImplementUtil.java

@@ -24,6 +24,7 @@ import com.jetbrains.python.PyNames;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.impl.PyFunctionBuilder;
 import com.jetbrains.python.psi.impl.PyPsiUtils;
+import com.jetbrains.python.psi.types.PyNoneType;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -163,6 +164,9 @@ public class PyOverrideImplementUtil {
     }, ArrayUtil.EMPTY_STRING_ARRAY);
     int startIndex = 0;
 
+    if (baseFunction.getReturnType() != PyNoneType.INSTANCE) {
+      statementBody.append("return ");
+    }
     if (baseClass.isNewStyleClass()) {
       statementBody.append(PyNames.SUPER);
       statementBody.append("(");

python/testData/override/returnValue.py

@@ -0,0 +1,6 @@
+class A:
+    def doStuff(self, foo=True): return True
+
+class B(A):
+    def otherMethod(self, foo, bar):
+        print foo, bar

python/testData/override/returnValue_after.py

@@ -0,0 +1,9 @@
+class A:
+    def doStuff(self, foo=True): return True
+
+class B(A):
+    def doStuff(self, foo=True):
+        <selection>return A.doStuff(self, foo)</selection>
+
+    def otherMethod(self, foo, bar):
+        print foo, bar

python/testSrc/com/jetbrains/python/PyOverrideTest.java

@@ -38,6 +38,10 @@ public class PyOverrideTest extends PyLightFixtureTestCase {
     doTest();
   }
 
+  public void testReturnValue() {  // PY-1537
+    doTest();
+  }
+
   public void testPy3k() {
     PythonLanguageLevelPusher.setForcedLanguageLevel(myFixture.getProject(), LanguageLevel.PYTHON31);
     try {