Migrate @Foxaii's nav-rejig for 8.0.0

lib/utils.php

@@ -24,3 +24,38 @@ function body_class($classes) {
   return $classes;
 }
 add_filter('body_class', __NAMESPACE__ . '\\body_class');
+
+/**
+ * Make a URL relative
+ */
+function root_relative_url($input) {
+  preg_match('|https?://([^/]+)(/.*)|i', $input, $matches);
+  if (!isset($matches[1]) || !isset($matches[2])) {
+    return $input;
+  } elseif (($matches[1] === $_SERVER['SERVER_NAME']) || $matches[1] === $_SERVER['SERVER_NAME'] . ':' . $_SERVER['SERVER_PORT']) {
+    return wp_make_link_relative($input);
+  } else {
+    return $input;
+  }
+}
+
+/**
+ * Compare URL against relative URL
+ */
+function url_compare($url, $rel) {
+  $url = trailingslashit($url);
+  $rel = trailingslashit($rel);
+  if ((strcasecmp($url, $rel) === 0) || root_relative_url($url) == $rel) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+/**
+ * Check if element is empty
+ */
+function is_element_empty($element) {
+  $element = trim($element);
+  return !empty($element);
+}