added tests for PY-3281

python/testData/intentions/demorgan/after4.py

@@ -0,0 +1,8 @@
+a = True
+b = False
+c = True
+d = False
+
+#before intention
+if not(not(a and b and c) and not d):
+    print "before"

python/testData/intentions/demorgan/before4.py

@@ -0,0 +1,8 @@
+a = True
+b = False
+c = True
+d = False
+
+#before intention
+if a and b and c or<caret> d:
+    print "before"

python/testSrc/com/jetbrains/python/PythonDemorganLawIntentionTest.java

@@ -20,6 +20,10 @@ public class PythonDemorganLawIntentionTest extends PyLightFixtureTestCase {
     doTest();
   }
 
+  public void test4() throws Exception {
+    doTest();
+  }
+
   private void doTest() throws Exception {
     myFixture.configureByFile("before" + getTestName(false) + ".py");
     final IntentionAction action = myFixture.findSingleIntention("DeMorgan Law");