How to add a permission : reorder Taxonomy terms

Question

I need some roles to be able to edit and add terms of specific vocabularies, but not to reorder them. How can I add the permission reorder foo vocabulary terms, reorder bar vocabulary terms... with a module or programmatically ?

AFAIK edit terms permissions immediately give you the permissions to reorder terms also.

I already tried these modules below but none implements such permission.

Vocabulary Permissions Per Role

Allows adding to/editing terms of/removing terms from vocabularies per role... adding terms to a vocabulary but not to another, reordering/editing terms of a vocabulary but not another's, etc.

Says so, but reordering /editing come together.

Taxonomy access fix

• adds 1 permission per vocabulary: "add terms in X"
• changes the way vocabulary specific permissions are handled
• changes the Taxonomy admin pages' access checks
• alters the vocabularies overview table to show only what you have access to edit or delete

The module does what native Taxonomy lacks: more specific Taxonomy permissions (and checking them correctly).

Thank you.

Answer 1

You need to implement hook_form_alter and remove the Sort alphabetically button based on the role.

Edit: Something like this (tested)

function mymod_form_alter(&$form, &$form_state, $form_id) {
  if (in_array('userrole', $user->roles) && ($form_id == 'taxonomy_overview_terms') {
    unset($form['actions']['reset_alphabetical']);
    drupal_add_css(drupal_get_path('module','mymod').'/css/mymod.css');
  }
}

and in css/mymod.css, do

.handle,.tabledrag-toggle-weight {display:none;}

This hides the Reset to alphabetical button, drag handles, and Show row weights link.

Answer 2

After digging a bit more into permission implementation, this is how I solved this issue, in combination with Taxonomy access fix.

/**
 * Implements hook_permission();
 */
function MYMODULE_permission() {
  return array(
    'reorder_taxonomy_terms' => array(
      'title' => t('Reorder taxonomy terms'),
      'description' => t('Allows users to reorder taxonomy terms.'),
    ),
  );
}

/**
 * Implements hook_js_alter().
 */
function MYMODULE_js_alter(&$javascript) {
  if (!user_access('reorder_taxonomy_terms')) {
    unset($javascript['misc/tabledrag.js']);
  }
}

/**
 * Implements hook_form_FORM_ID_alter();
 */
function MYMODULE_form_taxonomy_overview_terms_alter(&$form, &$form_state, $form_id) {
  global $user;
  if (!user_access('reorder_taxonomy_terms')) {
    foreach($form as $k=>$v){
      if(substr($k, 0, 3) == 'tid'){ 
        unset($form[$k]['weight']);
      }
    }
    unset($form['actions']['reset_alphabetical']);
    drupal_add_css(drupal_get_path('module','vts_taxonomy_permissions').'/MYMODULE.css');

  }
}

/**
 * Implements hook_FORM_ID_alter();
 */
function MYMODULE_form_taxonomy_form_term_alter(&$form, &$form_state, $form_id) {
  global $user; 
  if (!user_access('reorder_taxonomy_terms')){
    unset($form['relations']['weight']);
  }
}

In MYMODULE.css

/* Hide reorder help text */
#block-system-help {
  display: none;
}