Attempt at updating taxonomy term pattern.

islandlives.module

@@ -12,7 +12,7 @@ use Drupal\views\ViewExecutable;
  * Implements hook_pathauto_pattern_alter().
  */
 function islandlives_pathauto_pattern_alter(PathautoPatternInterface $pattern, array $context) {
-  // Only act on the repository_items pattern.
+  // Nodes: Only act if the pattern has machine name `repository_items`.
   if ($pattern->id() == 'repository_items') {
     // If node has no PID...
     $node = $context['data']['node'];
@@ -23,6 +23,17 @@ function islandlives_pathauto_pattern_alter(PathautoPatternInterface $pattern, a
       $pattern->setPattern($new_pattern);
     }
   }
+  // Taxonomy Terms: Only act if the pattern has machine name `person_vocabulary`.
+  if ($pattern->id() == 'person_vocabulary') {
+    // If term has no PID...
+    $term = $context['data']['taxonomy_term'];
+    $pid = $term->get('field_pid')->value;
+    if ($pid == NULL) {
+      // Replace the PID with the TID in the alias.
+      $new_pattern = preg_replace('/\[term:field_pid\]/', '[term:tid]', $pattern->getPattern());
+      $pattern->setPattern($new_pattern);
+    }
+  }
 }
 
 /**