@Test
public void invertMatcherShouldNegateTheOriginalMatchingResult() {
BugInstance bug = new BugInstance("UUF_UNUSED_FIELD", 0);
Matcher originalMatcher = FilterFactory.makeMatcher(asList(Sortables.BUGCODE), bug);
assertTrue("Original matcher should match bug.", originalMatcher.match(bug));
Matcher notMatcher = FilterFactory.invertMatcher(originalMatcher);
assertTrue("Should return an instance of NotMatcher.", notMatcher instanceof NotMatcher);
assertFalse("Inverted matcher should now not match.", notMatcher.match(bug));
}