phpunit custom asserts help needed

Question

I'm trying to add a custom assert to phpunit, following this tutorial, to validate complex numbers returned as a string (e.g.

"-123+456i"

by the method that I'm testing) to a defined precision for both the real and imaginary components. I've put a Complex.php class to parse the string into the real and imaginary parts, and put together the following assertion class as complexAssert.php:

require_once 'PHPUnit/Framework/Assert.php';
include_once getcwd().'/custom/Complex.php';

class complexAssert extends PHPUnit_Framework_Assert {

    public function assertComplexEquals($expected, $actual, $message = '', $delta = 0)
    {
        $expectedComplex = new Complex($expected);
        $actualComplex = new Complex($actual);

        if (!($actualComplex->getReal() >= ($expectedComplex - $delta) &&
            $actualComplex->getReal() <= ($expectedComplex + $delta))) {
            return $this->fail($message);
        }

        if (!($actualComplex->getImaginary() >= ($expectedComplex - $delta) &&
            $actualComplex->getImaginary() <= ($expectedComplex + $delta))) {
            return $this->fail($message);
        }

    }
}

My unit test script:

require_once getcwd().'/custom/complexAssert.php';
require_once 'testDataFileIterator.php';

class EngineeringTest extends PHPUnit_Framework_TestCase
{
    /**
     * @dataProvider providerIMSUM
     */
    public function testIMSUM()
    {
        $args = func_get_args();
        $expectedResult = array_pop($args);
        $result = call_user_func_array(array('PHPExcel_Calculation_Engineering','IMSUM'),$args);
        $this->assertComplexEquals($expectedResult, $result);
    }

    public function providerIMSUM()
    {
        return new testDataFileIterator('rawTestData/Calculation/Engineering/IMSUM.data');
    }
}

The unit tests worked without error (but failed) when I was simply doing an assertEquals... but now I've added the include and changed to my new assert, it's crashing claiming that it can't call the undefined method assertComplexEquals().

Has anybody had any success extending phpunit with custom asserts, and can see what I'm doing wrong?

Answer 1

Obviously the only way to get $this->someCustomAssertion worked is to extend PHPUnit_Framework_TestCase and create wrapper-methods there, or call your custom assertions statically.

Zend Framework, for example, just extends PHPUnit_Framework_TestCase with additional methods (assertions)