how to unit-test a php method_exists()

Question

having this code

<?php
public function trueOrFalse($handler) {
 if (method_exists($handler, 'isTrueOrFalse')) {
  $result= $handler::isTrueOrFalse;
  return $result;
 } else {
  return FALSE;
 }
}

how would you unit-test it? is there a chance to mock a $handler? obviously i would need some kind of

<?php
$handlerMock= \Mockery::mock(MyClass::class);
$handlerMock->shouldReceive('method_exists')->andReturn(TRUE);

but it cannot be done

Ker

Why you create method trueOrFalse you can check method_exists in code, because if method exist isTrue and always return true you can simple replace this to single method_exists() but if you method isTrue returned evrything data you can simple if(!method_exists) return false or several data, or you can create abstract class and set this method as require for parrenting. p.s. sorry for my English. – Bitt

this is just simplified. in fact isTrue returns boolean (false or true) as its result. so question is, is there a chance to test it like it is, or refactoring is needed? in that case, yes i would probably need to get rid of that method_exists out of the method – Ker

Answer 1

Okay In your testCase class you need to use the same namespace of your MyClass class. The trick is to override built-in functions in your current namespace. So assuming your class looks like the following:

namespace My\Namespace;

class MyClass
{
    public function methodExists() {
        if (method_exists($this, 'someMethod')) {
            return true;
        } else {
            return false;
        }
    }
}

Here is how the testCase class should look like:

namespace My\Namespace;//same namespace of the original class being tested
use \Mockery;

// Override method_exists() in current namespace for testing
function method_exists()
{
    return ExampleTest::$functions->method_exists();
}

class ExampleTest extends \PHPUnit_Framework_TestCase
{
    public static $functions;

    public function setUp()
    {
        self::$functions = Mockery::mock();
    }
    /**
     * A basic functional test example.
     *
     * @return void
     */
    public function testBasicExample()
    {
        self::$functions->shouldReceive('method_exists')->once()->andReturn(false);

        $myClass = new MyClass;
        $this->assertEquals($myClass->methodExists(), false);
    }

}

It works perfect for me. Hope this helps.

Caboodle