An uploaded file must be an array or an instance of UploadedFile issue

[antonioperic]

I am trying this test on Symfony app

Scenario: As logged User I cannot get attachment other users uploaded
   Given I send a POST request to "/rest/index.php" with parameters:
     | key     | value      |
     | foo     | bar        |
     | foofile | @dummy_img.png |
   And I add "Content-Type" header equal to "application/x-www-form-urlencoded"
   Then I should see "You have sent a POST request. "
   And I should see "1 parameter(s)"
   And I should see "1 file(s)"
   And I should see "foo : bar"
   And I should see "foofile - name : lorem.txt"
   And I should see "foofile - error : 0"
   And I should see "foofile - size : 39"

The problem I am getting is:

An uploaded file must be an array or an instance of UploadedFile. (InvalidArgumentException)

This is my behat config:

default:
  calls:
    error_reporting: 16383 # E_ALL & ~E_USER_DREPRECATED
  suites:
    default:
      contexts:
        - FeatureContext: { doctrine: "@doctrine" }
        - Behat\MinkExtension\Context\MinkContext
        - Sanpi\Behatch\Context\RestContext
        - JsonContext
        - MessageAttachmentContext
        - Fidry\AliceBundleExtension\Context\Doctrine\AliceORMContext
        - UserBundle\Behat\Context\UserContext
        - GatheringBundle\Behat\Context\GatheringContext
  extensions:
    Behat\Symfony2Extension:
      kernel:
        env: "test"
        debug: "true"
    Behat\MinkExtension:
      base_url: "http://example.com/"
      files_path: "%paths.base%/features/dummy/"
      sessions:
        default:
          symfony2: ~
    Sanpi\Behatch\Extension: ~
    Fidry\AliceBundleExtension\Extension:
      fixtures_base_path: ~ # default to %paths.base%/features/fixtures

Do I need to include some other context to get this working. key value is sent in files but for some reasons symfony cannot build that in ParatmerBag

[sanpii]

Which version of behatch/contexts do you use?