How to alter a form's name attribute

Question

I'm trying to override the Drupal Login form. I have been able to unset and modify pieces of it, but the last thing I am struggling with is the name attribute on the submit button. Currently, the button looks like this:

 <button class="btn btn-default form-submit" id="edit-submit" name="op" value="Log in" type="submit">Log in</button>

I am trying to get rid of the name attribute, but I don't see it listed as a array element when I dpm($form). How do I alter this

EDIT: I almost figured it out. I found that the below can be used to alter the name attribute, but I cant remove it, even if I set it equal to NULL. When set to null, it defaults to 'op':

$form['actions']['submit']['#attributes']['name'] = 'submit';

Answer 1

It's possible that "op" is a default that gets applied if there's nothing already there.

Try:

$form['#submit']['#attributes']['name'] = 'thing-you-want-to-call-it';

Answer 2

Ok, I finally found a solution, but if someone has a better one, please let me know.

I found that I wasn't able to modify the name attribute from the hook form alter, so I went higher up. I first tried altering the button with a preprocess function, which didn't work. I was only able to do it by overriding the actual theme_button. Code below (note: I'm using a bootstrap subtheme):

/**
* Overrides theme_button().
*/
function mytheme_button($variables) {
  $element = $variables['element'];
  $label = $element['#value'];
  element_set_attributes($element, array('id', 'name', 'value', 'type'));

  // If a button type class isn't present then add in default.
  $button_classes = array(
    'btn-default',
    'btn-primary',
    'btn-success',
    'btn-info',
    'btn-warning',
    'btn-danger',
    'btn-link',
  );
  $class_intersection = array_intersect($button_classes, $element['#attributes']['class']);
  if (empty($class_intersection)) {
    $element['#attributes']['class'][] = 'btn-default';
  }

  // Add in the button type class.
  $element['#attributes']['class'][] = 'form-' . $element['#button_type'];

  if($element['#type'] === 'submit') {
    unset($element['#attributes']['name']);
  }
  dpm($element);
  // This line break adds inherent margin between multiple buttons.
  return '<button' . drupal_attributes($element['#attributes']) . '>' . $label ."</button>\n";
}

function mytheme_preprocess_button($variables) {
    if($variables['element']['#type'] === 'submit') {
      unset($variables['element']['#name']);
 }
 dpm($variables);  
}

I found that I was able to remove the name attribute with this code in the mytheme_button

unset($element['#attributes']['name']);

but from inside the mytheme_preprocess_button, I was able to remove the #name attribute from the array with this

unset($variables['element']['#name']);

but it didn't actually remove the name from the form. In the preprocess, 'name' is not a sub element under '#attributes'.

Does this make sense? I would think the most Drupal solution would be to use the preprocess, if I can.