phpunit InvalidArgumentException的测试用例

Question

Please tell how to create test cases fro below function to test exception and messages is thrown correctly. I'm using Symfony 2.

public function validateParams(Graph $graph, $start, $destination)
{
    if (!is_object($graph)) {

        throw new \InvalidArgumentException('Graph param should be an object !');
    }

    if (empty($start)) {

        throw new \InvalidArgumentException('Start param is empty !');
    }

    if (empty($destination)) {

        throw new \InvalidArgumentException('Graph param is empty !');
    }

    return true;
}

I used below test case and it says, Failed asserting that exception of type "\InvalidArgumentException" is thrown.

 /**
 * @expectedException \InvalidArgumentException
 */
public function testValidateParamsWhenStartingPointIsEmpty()
{
   $this->shortestPathCalc= new ShortestPathCalculator();
   $this->shortestPathCalc->validateParams($this->graph, ' ', 'f', 'Expected exception not thrown when starting point is empty !');
}

Answer 1

The problem in your class is that the check with empty do:

From the doc

Returns FALSE if var exists and has a non-empty, non-zero value. Otherwise returns TRUE.

This test work fine for your validator class (green bar):

class ValidatorTest extends \PHPUnit_Framework_TestCase{

    /**
     * @expectedException InvalidArgumentException
     * @expectedExceptionMessage Start param is empty !
     */
    public function testA()
    {
        $validator = new Validator();
        $validator->validateParams(new Graph(),'',' ');
    }

Hope this help