Implement help for field administration

Problem/Motivation

While implementing 📌 Fix coding standards Needs work I found a large number of coding standard violations was caused by a code block in the hook_help() implementation that seems to be targeted at the field administration. As far as I can tell that is now working, so that would suggest this code needs to be resurrected. I am recording it here, because removing it in its commented-out form gets rid of a large number of code standard violations.

The code as found (note: I have no idea if this makes any sense whatsoever at this point).

    case 'field_ui.overview_flagging':
      // [...] 
      // Get the existing link types that provide a flagging form.
      $link_types = flag_get_link_types();
      $form_link_types = array();
      foreach (flag_get_link_types() as $link_type) {
        if ($link_type['provides form']) {
          $form_link_types[] = '<em>' . $link_type['title'] . '</em>';
        }
      }

      // Get the flag for which we're managing fields.
      $flag = menu_get_object('flag', FLAG_ADMIN_PATH_START + 1);

      // Common text.
      $output  = '<p>' . t('Flags can have fields added to them. For example, a "Spam" flag could have a <em>Reason</em> field where a user could type in why he believes the item flagged is spam. A "Bookmarks" flag could have a <em>Folder</em> field into which a user could arrange her bookmarks.') . '</p>';
      $output .= '<p>' . t('On this page you can add fields to flags, delete them, and otherwise manage them.') . '</p>';

      // Three cases:
      if ($flag->link_type == 'form') {
        // Case 1: the current link type is the flagging form. Don't tell the
        // user anything extra, all is fine.
      }
      elseif ($link_types[$flag->link_type]['provides form']) {
        // Case 2: the current link type shows the form for creation of the
        // flagging, but it not the flagging form. Tell the user they can't edit
        // existing flagging fields.
        $output .= t("Field values may be edited when flaggings are created because this flag's link type shows a form for the flagging. However, to edit field values on existing flaggings, you will need to set your flag to use the <em>Flagging form</em> link type. This is provided by the <em><a href='!flagging-form-url'>Flagging Form</a></em> module.", array(
          '!flagging-form-url' => 'http://drupal.org/project/flagging_form',
        ));
        if (!\Drupal::moduleHandler()->moduleExists('flagging_form')) {
          $output .= ' <span class="warning">'
            . t("You do not currently have this module enabled.")
            . '</span>';
        }
        $output .= '</p>';
      }
      else {
        // Case 3: the current link type does not allow access to the flagging
        // form. Tell the user they should change it.
        $output .= '<p class="warning">' . t("To allow users to enter values for fields you will need to <a href='!form-link-type-url'>set your flag</a> to use one of the following link types which allow users to access the flagging form: !link-types-list. (In case a form isn't used, the fields are assigned their default values.)", array(
          '!form-link-type-url' => url('admin/structure/flags/manage/' . $flag->name, array('fragment' => 'edit-link-type')),
          // The list of labels from link types. These are all defined in code
          // in hook_flag_link_type_info() and therefore safe to output raw.
          '!link-types-list' => implode(', ', $form_link_types),
        )) . '</p>';
        $output .= '<p>' . t("Additionally, to edit field values on existing flaggings, you will need to set your flag to use the Flagging form link type. This is provided by the <em><a href='!flagging-form-url'>Flagging Form</a></em> module.", array(
          '!flagging-form-url' => 'http://drupal.org/project/flagging_form',
        ));
        if (!\Drupal::moduleHandler()->moduleExists('flagging_form')) {
          $output .= ' <span class="warning">'
            . t("You do not currently have this module enabled.")
            . '</span>';
        }
        $output .= '</p>';
      }

      return $output;

Proposed resolution

Do a sanity check on this code and see if we can re-add it as-is. Otherwise, implement help that does make sense.

Remaining tasks

• Assess the above code
• Either add it back into hook_help or make an alternative implementation
• Review
• Merge

User interface changes

Help available for field UI screens for Flag (?)

API changes

None.

Data model changes

None.