new set test

guava/src/test/java/org/baeldung/guava/GuavaCollectionTypesTest.java

@@ -148,6 +148,15 @@ public class GuavaCollectionTypesTest {
         assertThat(intersection, containsInAnyOrder('b', 'c'));
     }
 
+    @Test
+    public void whenCalculatingSetSymetricDifference_thenCorrect() {
+        final Set<Character> first = ImmutableSet.of('a', 'b', 'c');
+        final Set<Character> second = ImmutableSet.of('b', 'c', 'd');
+
+        final Set<Character> intersection = Sets.symmetricDifference(first, second);
+        assertThat(intersection, containsInAnyOrder('a', 'd'));
+    }
+
     @Test
     public void whenCalculatingPowerSet_thenCorrect() {
         final Set<Character> chars = ImmutableSet.of('a', 'b');