How to catch PHP Warning in PHPUnit

Question

I am writing test cases and here is a question I have.

So say I am testing a simple function someClass::loadValue($value)

The normal test case

Answer 1

Make SomeClass throw an error when input is invalid and tell phpUnit to expect an error.

One method is this:

class ExceptionTest extends PHPUnit_Framework_TestCase
{
    public function testLoadValueWithNull()
    {
        $o = new SomeClass();            
        $this->setExpectedException('InvalidArgumentException');
        $this->assertInstanceOf('InvalidArgumentException', $o::loadValue(null));
    }
}

See documentation for more methods.