CODEWITHSUNDEEP
phpunit-testingmockingphpunit
Nathan
Nathan

Reputation: 11149

Mock objects which support chaining methods

I'm wondering if there's a fairly concise way of mocking objects which support chaining of methods... so for example, a database query object might have a method call that looks like this:

$result = $database->select('my_table')->where(array('my_field'=>'a_value'))->limit(1)->execute();

The problem comes if I have to mock two different select queries so that they return different results. Any ideas?

This is specifically about PHPUnit, but experiences from other unit testing frameworks will help.

Upvotes: 7

Views: 4109

Answers (3)

D_R
D_R

Reputation: 4962

I know its an old question, but it might help more to future googler's.

I was also having problems in finding a framework that will provide simple and easy syntax for mocking & stubbing method chainning. then I've decided to write a simple and easy-to-use mocking library.

Usage example:

 // Creating a new mock for SimpleClassForMocking
 $mock = ShortifyPunit::mock('SimpleClassForMocking');

  ShortifyPunit::when($mock)->first_method()
                            ->second_method(2,3)->returns(1);

  ShortifyPunit::when($mock)->first_method()
                            ->second_method(2,3,4)->returns(2);

  ShortifyPunit::when($mock)->first_method(1)
                            ->second_method(2,3,4)->returns(3);

  ShortifyPunit::when($mock)->first_method(1,2,3)
                            ->second_method(1,2)->third_method()->returns(4);

  $mock->first_method()->second_method(2,3); // returns 1
  $mock->first_method()->second_method(2,3,4); // returns 2
  $mock->first_method(1)->second_method(2,3,4); // returns 3
  $mock->first_method(1,2,3)->second_method(1,2)->third_method(); // return 4

GitHub:

https://github.com/danrevah/ShortifyPunit#stubbing-method-chanining

Upvotes: 1

Gordon
Gordon

Reputation: 316969

I am not sure this is what you are looking for, so please leave a comment:

class StubTest extends PHPUnit_Framework_TestCase
{
    public function testChainingStub()
    {
        // Creating the stub with the methods to be called
        $stub = $this->getMock('Zend_Db_Select', array(
            'select', 'where', 'limit', 'execute'
        ), array(), '', FALSE);

        // telling the stub to return a certain result on execute
        $stub->expects($this->any())
             ->method('execute')
             ->will($this->returnValue('expected result'));

        // telling the stub to return itself on any other calls
        $stub->expects($this->any())
             ->method($this->anything())
             ->will($this->returnValue($stub));

        // testing that we can chain the stub
        $this->assertSame(
            'expected result',
            $stub->select('my_table')
                 ->where(array('my_field'=>'a_value'))
                 ->limit(1)
                 ->execute()
        );
    }
}

You can combine this with expectations:

class StubTest extends PHPUnit_Framework_TestCase
{
    public function testChainingStub()
    {
        // Creating the stub with the methods to be called
        $stub = $this->getMock('Zend_Db_Select', array(
            'select', 'where', 'limit', 'execute'
        ), array(), '', FALSE);

        // overwriting stub to return something when execute is called
        $stub->expects($this->exactly(1))
             ->method('execute')
             ->will($this->returnValue('expected result'));

        $stub->expects($this->exactly(1))
             ->method('limit')
             ->with($this->equalTo(1))
             ->will($this->returnValue($stub));

        $stub->expects($this->exactly(1))
             ->method('where')
             ->with($this->equalTo(array('my_field'=>'a_value')))
             ->will($this->returnValue($stub));

        $stub->expects($this->exactly(1))
             ->method('select')
             ->with($this->equalTo('my_table'))
             ->will($this->returnValue($stub));

        // testing that we can chain the stub
        $this->assertSame(
            'expected result',
            $stub->select('my_table')
                 ->where(array('my_field'=>'a_value'))
                 ->limit(1)
                 ->execute()
        );
    }
}

Upvotes: 14

d11wtq
d11wtq

Reputation: 35308

This might not be the answer you're looking for, but I wrote a mock object framework a couple of years back that will handle this sort of "depends on the input" assertion fine:

http://code.google.com/p/yaymock/

http://code.google.com/p/yaymock/wiki/Expectations

I wrote it for use in the unit tests backing Swift Mailer but it hasn't been widely adopted by any other projects (that I know of). The purpose was to provide better control and introspection of mock object invocations than that provided by PHPUnit and SimpleTest.

Upvotes: 0

Related Questions