Codecept, unit test: How to mock POST DATA into the request object?

Thanks, I see now that what I was about to do was not unit testing but rather functional or integration testing.

Though I have no use for it right now I would still like to know if it's possible from inside Phalcon to manipulate the POST data that gets injected into the Request object.

I solved my issues like this (any critique is apperciated):

0) The unit I want to test is an extension of Phalcon\Mvc\Component

# MyApp/Library/SubmitIdentifier/SubmitIdentifier.php
<?php
namespace MyApp\Library\SubmitIdentifier;

use Phalcon\Mvc\User\Component;

class SubmitIdentifier extends Component
{
    /**
     * @var null|string
     */
    public $action = null;

    /**
     * part of a dispatch logic built around submit buttons
     * Submit button input fields must be named <submit_array_name>[xxx] (eg. btn[xxx]) where xxx identifies the intended action (decided by the developer)
     * Because the "value" of a submit button is used for non-data purposes the xxx-key replaces this functionality
     * it is through this possible to treat the xxx-key equivalently to the "value" of other form fields
     *  
     * @param string  $submit_array_name root name of the button array: default is btn
     * 
     */
    public function initialize($submit_array_name='btn')
    {
        if ($this->request->isPost() && $this->request->has($submit_array_name)) {
            $btn = $this->request->get($submit_array_name);
            if(is_array($btn)) {
                $this->action = key($btn);
            }
        }
    }

    /**
     * Returns the index for the pressed button in the btn[] array
     * @return mixed|null
     */
    public function getAction($submit_array_name='btn')
    {
        if(is_null($this->action)) {
            $this->initialize($submit_array_name);
        }
        return $this->action;
    }
}

1) I created a special request class extending Phalcon\Http\Request

#tests/unit/SubmitIdentifierHelper.php
<?php
class SubmitIdentifierHelper extends \Phalcon\Http\Request 
{
    public $post_data;

    public function isPost() {
        $res = parent::isPost();
        return true;
    }
    public function has($name) {
        $res = parent::has($name);
        return true;
    }
    public function get($name=null,$filters=null,$defaultValue=null) {
        $res = parent::get($name,$filters,$defaultValue);
        return $this->post_data[$name];
    }
}

2) I set up my test like this:

#tests/unit/SubmitIdentifierTest.php
<?php

class SubmitIdentifierTest extends \Codeception\TestCase\Test
{
    ...

    public function testSubmitIdentifier()
    {
        $SubmitIdentifier = new \MyApp\Library\SubmitIdentifier\SubmitIdentifier();

        include __DIR__."/SubmitIdentifierHelper.php";
        $SubmitIdentifier->request = new SubmitIdentifierHelper();
        $SubmitIdentifier->request->post_data = array('btn' => array('cmp_submit'=>null));

        $this->assertEquals('cmp_submit',$SubmitIdentifier->getAction());
    }
}