@Test
public void testAllowsABeforeB() {

	assertTrue(this.set.allowsABeforeB(A, B));
	assertTrue(this.set.allowsABeforeB(A, C));
	assertTrue(this.set.allowsABeforeB(A, D));
	assertTrue(this.set.allowsABeforeB(B, C));
	assertTrue(this.set.allowsABeforeB(B, D));
	assertTrue(this.set.allowsABeforeB(C, D));
	assertFalse(this.set.allowsABeforeB(B, A));
	assertFalse(this.set.allowsABeforeB(C, A));
	assertFalse(this.set.allowsABeforeB(D, A));
	assertFalse(this.set.allowsABeforeB(C, B));
	assertFalse(this.set.allowsABeforeB(D, B));
	assertFalse(this.set.allowsABeforeB(D, C));
}