public function testGap() { $dr1 = new DateRange(new DateTime('2006-07-08'), new DateTime('2006-09-05')); $dr2 = new DateRange(new DateTime('2006-09-09'), new DateTime('2006-09-15')); $this->assertEquals(3, $dr2->gap($dr1)); $this->assertEquals(3, $dr1->gap($dr2)); $dr3 = new DateRange(new DateTime('2006-09-04'), new DateTime('2006-09-15')); $this->assertFalse($dr1->gap($dr3)); $this->assertFalse($dr3->gap($dr1)); }