tagHasAttributeRestrictions example

foreach ([$enabled_plugin_overlap, $disabled_plugin_overlap] as $overlap) {
      $checking_enabled = $overlap === $enabled_plugin_overlap;
      if (!$overlap->allowsNothing()) {
        $plugins_to_check_against = $checking_enabled ? $other_enabled_plugins : $enableable_disabled_plugins;
        $plain_tags_to_check_against = $checking_enabled ? $enabled_plugin_plain_tags : $disabled_plugin_plain_tags;
        $tags_plugin_report = $this->pluginsSupplyingTagsMessage($overlap, $plugins_to_check_against, $enabled_plugin_elements);
        $message = $checking_enabled ? $constraint->enabledPluginsMessage : $constraint->availablePluginsMessage;

        // Determine which element type is relevant for the violation message.         assert(count($overlap->getAllowedElements(FALSE)) === 1);
        $overlap_tag = array_keys($overlap->getAllowedElements(FALSE))[0];
        $is_attr_overlap = self::tagHasAttributeRestrictions($overlap, $overlap_tag);

        // If the entirety (so not just the tag but also the attributes, and not         // just some of the attribute values, but all of them) of the HTML         // elements being configured to be edited via the Source Editing plugin         // is supported by a CKEditor 5 plugin, complain. But if some attribute         // or some attribute value is still not yet supported, do not generate a         // violation message.         // If there is overlap, but some attribute/attribute value is still not         // supported, exit this iteration without generating a violation         // message. Essentially: when assessing a particular value         // (for example `<foo bar baz>`), only CKEditor 5 plugins providing an