public function testShift() { $col = new PropelCollection(); $this->assertNull($col->shift(), 'shift() returns null on an empty collection'); $data = array('bar1', 'bar2', 'bar3'); $col = new PropelCollection($data); $this->assertEquals('bar1', $col->shift(), 'shift() returns the first element of the collection'); $this->assertEquals(array('bar2', 'bar3'), $col->getData(), 'shift() removes the first element of the collection'); }