Question

I am writing a test for file download during which I am using the original_filename. I was able to mock the file upload using fixture_file_upload. But how to stub/mock the original_filename call.

def import_for_photo(picture_url, user)
  remote_photo = open(picture_url)
  remote_photo.original_filename = "#{user.id}.jpg"
  user.update_attributes({:picture => remote_photo})
end

The test

def test_import_for_photo
  fixture_file = fixture_file_upload(File.join('files', 'test.jpg'), 'image/jpeg')
  OpenURI.expects(:open_uri).returns(fixture_file)
  import_for_photo("http://dummy_url.com/dummy.jpg", users(:one))
  assert_equal "1.jpg", users(:one).reload.picture_file_name
end

Test output,

NoMethodError: undefined method `original_filename=' for #<File:/tmp/test.jpg20120512-4253-x673nc-0>

I know why this test fails, but how to fix it ?

Answer 1

Found out the solution. Instead of trying to stub :original_filename, I stubbed :original_filename= (notice the ‘=’) and my problem was solved !

Here is the code

def test_import_for_photo
  fixture_file = fixture_file_upload(File.join('files', 'test.jpg'), 'image/jpeg')
  fixture_file.expects(:original_filename=)
  OpenURI.expects(:open_uri).returns(fixture_file)
  import_for_photo("http://dummy_url.com/dummy.jpg", users(:one))
  assert_equal "1.jpg", users(:one).reload.picture_file_name
end