fixed PY-9660 Convert Method to Property: provokes Getter should return something when converting function which has return without return value

python/src/com/jetbrains/python/codeInsight/intentions/PyConvertMethodToPropertyIntention.java

@@ -49,8 +49,10 @@ public class PyConvertMethodToPropertyIntention extends BaseIntentionAction {
     function.accept(new PyRecursiveElementVisitor() {
       @Override
       public void visitPyReturnStatement(PyReturnStatement node) {
-        available[0] = true;
+        if (node.getExpression() != null)
+          available[0] = true;
       }
+
     });
 
     return available[0];

python/testData/intentions/PyConvertMethodToPropertyIntentionTest/emptyReturn.py

@@ -0,0 +1,3 @@
+class A():
+    def mo<caret>o(self):
+        return

python/testSrc/com/jetbrains/python/intentions/PyConvertMethodToPropertyIntentionTest.java

@@ -23,6 +23,10 @@ public class PyConvertMethodToPropertyIntentionTest extends PyIntentionTestCase
     doNegateIntentionTest(PyBundle.message("INTN.convert.method.to.property"));
   }
 
+  public void testEmptyReturn() throws Exception {
+    doNegateIntentionTest(PyBundle.message("INTN.convert.method.to.property"));
+  }
+
   public void testNoReturn() throws Exception {
     doNegateIntentionTest(PyBundle.message("INTN.convert.method.to.property"));
   }