1<?php
2/**
3 * Nav Menu API: Template functions
4 *
5 * @package WordPress
6 * @subpackage Nav_Menus
7 * @since 3.0.0
8 */
9
10// Don't load directly.
11if ( ! defined( 'ABSPATH' ) ) {
12 die( '-1' );
13}
14
15/** Walker_Nav_Menu class */
16require_once ABSPATH . WPINC . '/class-walker-nav-menu.php';
17
18/**
19 * Displays a navigation menu.
20 *
21 * @since 3.0.0
22 * @since 4.7.0 Added the `item_spacing` argument.
23 * @since 5.5.0 Added the `container_aria_label` argument.
24 *
25 * @param array $args {
26 * Optional. Array of nav menu arguments.
27 *
28 * @type int|string|WP_Term $menu Desired menu. Accepts a menu ID, slug, name, or object.
29 * Default empty.
30 * @type string $menu_class CSS class to use for the ul element which forms the menu.
31 * Default 'menu'.
32 * @type string $menu_id The ID that is applied to the ul element which forms the menu.
33 * Default is the menu slug, incremented.
34 * @type string $container Whether to wrap the ul, and what to wrap it with.
35 * Default 'div'.
36 * @type string $container_class Class that is applied to the container.
37 * Default 'menu-{menu slug}-container'.
38 * @type string $container_id The ID that is applied to the container. Default empty.
39 * @type string $container_aria_label The aria-label attribute that is applied to the container
40 * when it's a nav element. Default empty.
41 * @type callable|false $fallback_cb If the menu doesn't exist, a callback function will fire.
42 * Default is 'wp_page_menu'. Set to false for no fallback.
43 * @type string $before Text before the link markup. Default empty.
44 * @type string $after Text after the link markup. Default empty.
45 * @type string $link_before Text before the link text. Default empty.
46 * @type string $link_after Text after the link text. Default empty.
47 * @type bool $echo Whether to echo the menu or return it. Default true.
48 * @type int $depth How many levels of the hierarchy are to be included.
49 * 0 means all. Default 0.
50 * Default 0.
51 * @type object $walker Instance of a custom walker class. Default empty.
52 * @type string $theme_location Theme location to be used. Must be registered with
53 * register_nav_menu() in order to be selectable by the user.
54 * @type string $items_wrap How the list items should be wrapped. Uses printf() format with
55 * numbered placeholders. Default is a ul with an id and class.
56 * @type string $item_spacing Whether to preserve whitespace within the menu's HTML.
57 * Accepts 'preserve' or 'discard'. Default 'preserve'.
58 * }
59 * @return void|string|false Void if 'echo' argument is true, menu output if 'echo' is false.
60 * False if there are no items or no menu was found.
61 */
62function wp_nav_menu( $args = array() ) {
63 static $menu_id_slugs = array();
64
65 $defaults = array(
66 'menu' => '',
67 'container' => 'div',
68 'container_class' => '',
69 'container_id' => '',
70 'container_aria_label' => '',
71 'menu_class' => 'menu',
72 'menu_id' => '',
73 'echo' => true,
74 'fallback_cb' => 'wp_page_menu',
75 'before' => '',
76 'after' => '',
77 'link_before' => '',
78 'link_after' => '',
79 'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
80 'item_spacing' => 'preserve',
81 'depth' => 0,
82 'walker' => '',
83 'theme_location' => '',
84 );
85
86 $args = wp_parse_args( $args, $defaults );
87
88 if ( ! in_array( $args['item_spacing'], array( 'preserve', 'discard' ), true ) ) {
89 // Invalid value, fall back to default.
90 $args['item_spacing'] = $defaults['item_spacing'];
91 }
92
93 /**
94 * Filters the arguments used to display a navigation menu.
95 *
96 * @since 3.0.0
97 *
98 * @see wp_nav_menu()
99 *
100 * @param array $args Array of wp_nav_menu() arguments.
101 */
102 $args = apply_filters( 'wp_nav_menu_args', $args );
103 $args = (object) $args;
104
105 /**
106 * Filters whether to short-circuit the wp_nav_menu() output.
107 *
108 * Returning a non-null value from the filter will short-circuit wp_nav_menu(),
109 * echoing that value if $args->echo is true, returning that value otherwise.
110 *
111 * @since 3.9.0
112 *
113 * @see wp_nav_menu()
114 *
115 * @param string|null $output Nav menu output to short-circuit with. Default null.
116 * @param stdClass $args An object containing wp_nav_menu() arguments.
117 */
118 $nav_menu = apply_filters( 'pre_wp_nav_menu', null, $args );
119
120 if ( null !== $nav_menu ) {
121 if ( $args->echo ) {
122 echo $nav_menu;
123 return;
124 }
125
126 return $nav_menu;
127 }
128
129 // Get the nav menu based on the requested menu.
130 $menu = wp_get_nav_menu_object( $args->menu );
131
132 // Get the nav menu based on the theme_location.
133 $locations = get_nav_menu_locations();
134 if ( ! $menu && $args->theme_location && $locations && isset( $locations[ $args->theme_location ] ) ) {
135 $menu = wp_get_nav_menu_object( $locations[ $args->theme_location ] );
136 }
137
138 // Get the first menu that has items if we still can't find a menu.
139 if ( ! $menu && ! $args->theme_location ) {
140 $menus = wp_get_nav_menus();
141 foreach ( $menus as $menu_maybe ) {
142 $menu_items = wp_get_nav_menu_items( $menu_maybe->term_id, array( 'update_post_term_cache' => false ) );
143 if ( $menu_items ) {
144 $menu = $menu_maybe;
145 break;
146 }
147 }
148 }
149
150 if ( empty( $args->menu ) ) {
151 $args->menu = $menu;
152 }
153
154 // If the menu exists, get its items.
155 if ( $menu && ! is_wp_error( $menu ) && ! isset( $menu_items ) ) {
156 $menu_items = wp_get_nav_menu_items( $menu->term_id, array( 'update_post_term_cache' => false ) );
157 }
158
159 /*
160 * If no menu was found:
161 * - Fall back (if one was specified), or bail.
162 *
163 * If no menu items were found:
164 * - Fall back, but only if no theme location was specified.
165 * - Otherwise, bail.
166 */
167 if ( ( ! $menu || is_wp_error( $menu ) || ( isset( $menu_items ) && empty( $menu_items ) && ! $args->theme_location ) )
168 && isset( $args->fallback_cb ) && $args->fallback_cb && is_callable( $args->fallback_cb ) ) {
169 return call_user_func( $args->fallback_cb, (array) $args );
170 }
171
172 if ( ! $menu || is_wp_error( $menu ) ) {
173 return false;
174 }
175
176 $nav_menu = '';
177 $items = '';
178
179 $show_container = false;
180 if ( $args->container ) {
181 /**
182 * Filters the list of HTML tags that are valid for use as menu containers.
183 *
184 * @since 3.0.0
185 *
186 * @param string[] $tags The acceptable HTML tags for use as menu containers.
187 * Default is array containing 'div' and 'nav'.
188 */
189 $allowed_tags = apply_filters( 'wp_nav_menu_container_allowedtags', array( 'div', 'nav' ) );
190
191 if ( is_string( $args->container ) && in_array( $args->container, $allowed_tags, true ) ) {
192 $show_container = true;
193 $class = $args->container_class ? ' class="' . esc_attr( $args->container_class ) . '"' : ' class="menu-' . $menu->slug . '-container"';
194 $id = $args->container_id ? ' id="' . esc_attr( $args->container_id ) . '"' : '';
195 $aria_label = ( 'nav' === $args->container && $args->container_aria_label ) ? ' aria-label="' . esc_attr( $args->container_aria_label ) . '"' : '';
196 $nav_menu .= '<' . $args->container . $id . $class . $aria_label . '>';
197 }
198 }
199
200 // Set up the $menu_item variables.
201 _wp_menu_item_classes_by_context( $menu_items );
202
203 $sorted_menu_items = array();
204 $menu_items_with_children = array();
205 foreach ( (array) $menu_items as $menu_item ) {
206 /*
207 * Fix invalid `menu_item_parent`. See: https://core.trac.wordpress.org/ticket/56926.
208 * Compare as strings. Plugins may change the ID to a string.
209 */
210 if ( (string) $menu_item->ID === (string) $menu_item->menu_item_parent ) {
211 $menu_item->menu_item_parent = 0;
212 }
213
214 $sorted_menu_items[ $menu_item->menu_order ] = $menu_item;
215 if ( $menu_item->menu_item_parent ) {
216 $menu_items_with_children[ $menu_item->menu_item_parent ] = true;
217 }
218 }
219
220 // Add the menu-item-has-children class where applicable.
221 if ( $menu_items_with_children ) {
222 foreach ( $sorted_menu_items as &$menu_item ) {
223 if ( isset( $menu_items_with_children[ $menu_item->ID ] ) ) {
224 $menu_item->classes[] = 'menu-item-has-children';
225 }
226 }
227 }
228
229 unset( $menu_items, $menu_item );
230
231 /**
232 * Filters the sorted list of menu item objects before generating the menu's HTML.
233 *
234 * @since 3.1.0
235 *
236 * @param array $sorted_menu_items The menu items, sorted by each menu item's menu order.
237 * @param stdClass $args An object containing wp_nav_menu() arguments.
238 */
239 $sorted_menu_items = apply_filters( 'wp_nav_menu_objects', $sorted_menu_items, $args );
240
241 $items .= walk_nav_menu_tree( $sorted_menu_items, $args->depth, $args );
242 unset( $sorted_menu_items );
243
244 // Attributes.
245 if ( ! empty( $args->menu_id ) ) {
246 $wrap_id = $args->menu_id;
247 } else {
248 $wrap_id = 'menu-' . $menu->slug;
249
250 while ( in_array( $wrap_id, $menu_id_slugs, true ) ) {
251 if ( preg_match( '#-(\d+)$#', $wrap_id, $matches ) ) {
252 $wrap_id = preg_replace( '#-(\d+)$#', '-' . ++$matches[1], $wrap_id );
253 } else {
254 $wrap_id = $wrap_id . '-1';
255 }
256 }
257 }
258 $menu_id_slugs[] = $wrap_id;
259
260 $wrap_class = $args->menu_class ? $args->menu_class : '';
261
262 /**
263 * Filters the HTML list content for navigation menus.
264 *
265 * @since 3.0.0
266 *
267 * @see wp_nav_menu()
268 *
269 * @param string $items The HTML list content for the menu items.
270 * @param stdClass $args An object containing wp_nav_menu() arguments.
271 */
272 $items = apply_filters( 'wp_nav_menu_items', $items, $args );
273 /**
274 * Filters the HTML list content for a specific navigation menu.
275 *
276 * @since 3.0.0
277 *
278 * @see wp_nav_menu()
279 *
280 * @param string $items The HTML list content for the menu items.
281 * @param stdClass $args An object containing wp_nav_menu() arguments.
282 */
283 $items = apply_filters( "wp_nav_menu_{$menu->slug}_items", $items, $args );
284
285 // Don't print any markup if there are no items at this point.
286 if ( empty( $items ) ) {
287 return false;
288 }
289
290 $nav_menu .= sprintf( $args->items_wrap, esc_attr( $wrap_id ), esc_attr( $wrap_class ), $items );
291 unset( $items );
292
293 if ( $show_container ) {
294 $nav_menu .= '</' . $args->container . '>';
295 }
296
297 /**
298 * Filters the HTML content for navigation menus.
299 *
300 * @since 3.0.0
301 *
302 * @see wp_nav_menu()
303 *
304 * @param string $nav_menu The HTML content for the navigation menu.
305 * @param stdClass $args An object containing wp_nav_menu() arguments.
306 */
307 $nav_menu = apply_filters( 'wp_nav_menu', $nav_menu, $args );
308
309 if ( $args->echo ) {
310 echo $nav_menu;
311 } else {
312 return $nav_menu;
313 }
314}
315
316/**
317 * Adds the class property classes for the current context, if applicable.
318 *
319 * @access private
320 * @since 3.0.0
321 *
322 * @global WP_Query $wp_query WordPress Query object.
323 * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
324 *
325 * @param array $menu_items The current menu item objects to which to add the class property information.
326 */
327function _wp_menu_item_classes_by_context( &$menu_items ) {
328 global $wp_query, $wp_rewrite;
329
330 $queried_object = $wp_query->get_queried_object();
331 $queried_object_id = (int) $wp_query->queried_object_id;
332
333 $active_object = '';
334 $active_ancestor_item_ids = array();
335 $active_parent_item_ids = array();
336 $active_parent_object_ids = array();
337 $possible_taxonomy_ancestors = array();
338 $possible_object_parents = array();
339 $home_page_id = (int) get_option( 'page_for_posts' );
340
341 if ( $wp_query->is_singular && ! empty( $queried_object->post_type ) && ! is_post_type_hierarchical( $queried_object->post_type ) ) {
342 foreach ( (array) get_object_taxonomies( $queried_object->post_type ) as $taxonomy ) {
343 if ( is_taxonomy_hierarchical( $taxonomy ) ) {
344 $term_hierarchy = _get_term_hierarchy( $taxonomy );
345 $terms = wp_get_object_terms( $queried_object_id, $taxonomy, array( 'fields' => 'ids' ) );
346 if ( is_array( $terms ) ) {
347 $possible_object_parents = array_merge( $possible_object_parents, $terms );
348 $term_to_ancestor = array();
349 foreach ( (array) $term_hierarchy as $ancestor => $descendents ) {
350 foreach ( (array) $descendents as $desc ) {
351 $term_to_ancestor[ $desc ] = $ancestor;
352 }
353 }
354
355 foreach ( $terms as $desc ) {
356 do {
357 $possible_taxonomy_ancestors[ $taxonomy ][] = $desc;
358 if ( isset( $term_to_ancestor[ $desc ] ) ) {
359 $_desc = $term_to_ancestor[ $desc ];
360 unset( $term_to_ancestor[ $desc ] );
361 $desc = $_desc;
362 } else {
363 $desc = 0;
364 }
365 } while ( ! empty( $desc ) );
366 }
367 }
368 }
369 }
370 } elseif ( ! empty( $queried_object->taxonomy ) && is_taxonomy_hierarchical( $queried_object->taxonomy ) ) {
371 $term_hierarchy = _get_term_hierarchy( $queried_object->taxonomy );
372 $term_to_ancestor = array();
373 foreach ( (array) $term_hierarchy as $ancestor => $descendents ) {
374 foreach ( (array) $descendents as $desc ) {
375 $term_to_ancestor[ $desc ] = $ancestor;
376 }
377 }
378 $desc = $queried_object->term_id;
379 do {
380 $possible_taxonomy_ancestors[ $queried_object->taxonomy ][] = $desc;
381 if ( isset( $term_to_ancestor[ $desc ] ) ) {
382 $_desc = $term_to_ancestor[ $desc ];
383 unset( $term_to_ancestor[ $desc ] );
384 $desc = $_desc;
385 } else {
386 $desc = 0;
387 }
388 } while ( ! empty( $desc ) );
389 }
390
391 $possible_object_parents = array_filter( $possible_object_parents );
392
393 $front_page_url = home_url();
394 $front_page_id = (int) get_option( 'page_on_front' );
395 $privacy_policy_page_id = (int) get_option( 'wp_page_for_privacy_policy' );
396
397 foreach ( (array) $menu_items as $key => $menu_item ) {
398
399 $menu_items[ $key ]->current = false;
400
401 $classes = (array) $menu_item->classes;
402 $classes[] = 'menu-item';
403 $classes[] = 'menu-item-type-' . $menu_item->type;
404 $classes[] = 'menu-item-object-' . $menu_item->object;
405
406 // This menu item is set as the 'Front Page'.
407 if ( 'post_type' === $menu_item->type && $front_page_id === (int) $menu_item->object_id ) {
408 $classes[] = 'menu-item-home';
409 }
410
411 // This menu item is set as the 'Privacy Policy Page'.
412 if ( 'post_type' === $menu_item->type && $privacy_policy_page_id === (int) $menu_item->object_id ) {
413 $classes[] = 'menu-item-privacy-policy';
414 }
415
416 // If the menu item corresponds to a taxonomy term for the currently queried non-hierarchical post object.
417 if ( $wp_query->is_singular && 'taxonomy' === $menu_item->type
418 && in_array( (int) $menu_item->object_id, $possible_object_parents, true )
419 ) {
420 $active_parent_object_ids[] = (int) $menu_item->object_id;
421 $active_parent_item_ids[] = (int) $menu_item->db_id;
422 $active_object = $queried_object->post_type;
423
424 // If the menu item corresponds to the currently queried post or taxonomy object.
425 } elseif (
426 (int) $menu_item->object_id === $queried_object_id
427 && (
428 ( ! empty( $home_page_id ) && 'post_type' === $menu_item->type
429 && $wp_query->is_home && $home_page_id === (int) $menu_item->object_id )
430 || ( 'post_type' === $menu_item->type && $wp_query->is_singular )
431 || ( 'taxonomy' === $menu_item->type
432 && ( $wp_query->is_category || $wp_query->is_tag || $wp_query->is_tax )
433 && $queried_object->taxonomy === $menu_item->object )
434 )
435 ) {
436 $classes[] = 'current-menu-item';
437 $menu_items[ $key ]->current = true;
438 $ancestor_id = (int) $menu_item->db_id;
439
440 while (
441 ( $ancestor_id = (int) get_post_meta( $ancestor_id, '_menu_item_menu_item_parent', true ) )
442 && ! in_array( $ancestor_id, $active_ancestor_item_ids, true )
443 ) {
444 $active_ancestor_item_ids[] = $ancestor_id;
445 }
446
447 if ( 'post_type' === $menu_item->type && 'page' === $menu_item->object ) {
448 // Back compat classes for pages to match wp_page_menu().
449 $classes[] = 'page_item';
450 $classes[] = 'page-item-' . $menu_item->object_id;
451 $classes[] = 'current_page_item';
452 }
453
454 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
455 $active_parent_object_ids[] = (int) $menu_item->post_parent;
456 $active_object = $menu_item->object;
457
458 // If the menu item corresponds to the currently queried post type archive.
459 } elseif (
460 'post_type_archive' === $menu_item->type
461 && is_post_type_archive( array( $menu_item->object ) )
462 ) {
463 $classes[] = 'current-menu-item';
464 $menu_items[ $key ]->current = true;
465 $ancestor_id = (int) $menu_item->db_id;
466
467 while (
468 ( $ancestor_id = (int) get_post_meta( $ancestor_id, '_menu_item_menu_item_parent', true ) )
469 && ! in_array( $ancestor_id, $active_ancestor_item_ids, true )
470 ) {
471 $active_ancestor_item_ids[] = $ancestor_id;
472 }
473
474 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
475
476 // If the menu item corresponds to the currently requested URL.
477 } elseif ( 'custom' === $menu_item->object && isset( $_SERVER['HTTP_HOST'] ) ) {
478 $_root_relative_current = untrailingslashit( $_SERVER['REQUEST_URI'] );
479
480 // If it's the customize page then it will strip the query var off the URL before entering the comparison block.
481 if ( is_customize_preview() ) {
482 $_root_relative_current = strtok( untrailingslashit( $_SERVER['REQUEST_URI'] ), '?' );
483 }
484
485 $current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_root_relative_current );
486 $raw_item_url = strpos( $menu_item->url, '#' ) ? substr( $menu_item->url, 0, strpos( $menu_item->url, '#' ) ) : $menu_item->url;
487 $item_url = set_url_scheme( untrailingslashit( $raw_item_url ) );
488 $_indexless_current = untrailingslashit( preg_replace( '/' . preg_quote( $wp_rewrite->index, '/' ) . '$/', '', $current_url ) );
489
490 $matches = array(
491 $current_url,
492 urldecode( $current_url ),
493 $_indexless_current,
494 urldecode( $_indexless_current ),
495 $_root_relative_current,
496 urldecode( $_root_relative_current ),
497 );
498
499 if ( $raw_item_url && in_array( $item_url, $matches, true ) ) {
500 $classes[] = 'current-menu-item';
501 $menu_items[ $key ]->current = true;
502 $ancestor_id = (int) $menu_item->db_id;
503
504 while (
505 ( $ancestor_id = (int) get_post_meta( $ancestor_id, '_menu_item_menu_item_parent', true ) )
506 && ! in_array( $ancestor_id, $active_ancestor_item_ids, true )
507 ) {
508 $active_ancestor_item_ids[] = $ancestor_id;
509 }
510
511 if ( in_array( home_url(), array( untrailingslashit( $current_url ), untrailingslashit( $_indexless_current ) ), true ) ) {
512 // Back compat for home link to match wp_page_menu().
513 $classes[] = 'current_page_item';
514 }
515 $active_parent_item_ids[] = (int) $menu_item->menu_item_parent;
516 $active_parent_object_ids[] = (int) $menu_item->post_parent;
517 $active_object = $menu_item->object;
518
519 // Give front page item the 'current-menu-item' class when extra query arguments are involved.
520 } elseif ( $item_url === $front_page_url && is_front_page() ) {
521 $classes[] = 'current-menu-item';
522 }
523
524 if ( untrailingslashit( $item_url ) === home_url() ) {
525 $classes[] = 'menu-item-home';
526 }
527 }
528
529 // Back-compat with wp_page_menu(): add "current_page_parent" to static home page link for any non-page query.
530 if ( ! empty( $home_page_id ) && 'post_type' === $menu_item->type
531 && empty( $wp_query->is_page ) && $home_page_id === (int) $menu_item->object_id
532 ) {
533 $classes[] = 'current_page_parent';
534 }
535
536 $menu_items[ $key ]->classes = array_unique( $classes );
537 }
538 $active_ancestor_item_ids = array_filter( array_unique( $active_ancestor_item_ids ) );
539 $active_parent_item_ids = array_filter( array_unique( $active_parent_item_ids ) );
540 $active_parent_object_ids = array_filter( array_unique( $active_parent_object_ids ) );
541
542 // Set parent's class.
543 foreach ( (array) $menu_items as $key => $parent_item ) {
544 $classes = (array) $parent_item->classes;
545 $menu_items[ $key ]->current_item_ancestor = false;
546 $menu_items[ $key ]->current_item_parent = false;
547
548 if (
549 isset( $parent_item->type )
550 && (
551 // Ancestral post object.
552 (
553 'post_type' === $parent_item->type
554 && ! empty( $queried_object->post_type )
555 && is_post_type_hierarchical( $queried_object->post_type )
556 && in_array( (int) $parent_item->object_id, $queried_object->ancestors, true )
557 && (int) $parent_item->object_id !== $queried_object->ID
558 ) ||
559
560 // Ancestral term.
561 (
562 'taxonomy' === $parent_item->type
563 && isset( $possible_taxonomy_ancestors[ $parent_item->object ] )
564 && in_array( (int) $parent_item->object_id, $possible_taxonomy_ancestors[ $parent_item->object ], true )
565 && (
566 ! isset( $queried_object->term_id ) ||
567 (int) $parent_item->object_id !== $queried_object->term_id
568 )
569 )
570 )
571 ) {
572 if ( ! empty( $queried_object->taxonomy ) ) {
573 $classes[] = 'current-' . $queried_object->taxonomy . '-ancestor';
574 } else {
575 $classes[] = 'current-' . $queried_object->post_type . '-ancestor';
576 }
577 }
578
579 if ( in_array( (int) $parent_item->db_id, $active_ancestor_item_ids, true ) ) {
580 $classes[] = 'current-menu-ancestor';
581
582 $menu_items[ $key ]->current_item_ancestor = true;
583 }
584 if ( in_array( (int) $parent_item->db_id, $active_parent_item_ids, true ) ) {
585 $classes[] = 'current-menu-parent';
586
587 $menu_items[ $key ]->current_item_parent = true;
588 }
589 if ( in_array( (int) $parent_item->object_id, $active_parent_object_ids, true ) ) {
590 $classes[] = 'current-' . $active_object . '-parent';
591 }
592
593 if ( 'post_type' === $parent_item->type && 'page' === $parent_item->object ) {
594 // Back compat classes for pages to match wp_page_menu().
595 if ( in_array( 'current-menu-parent', $classes, true ) ) {
596 $classes[] = 'current_page_parent';
597 }
598 if ( in_array( 'current-menu-ancestor', $classes, true ) ) {
599 $classes[] = 'current_page_ancestor';
600 }
601 }
602
603 $menu_items[ $key ]->classes = array_unique( $classes );
604 }
605}
606
607/**
608 * Retrieves the HTML list content for nav menu items.
609 *
610 * @uses Walker_Nav_Menu to create HTML list content.
611 * @since 3.0.0
612 *
613 * @param array $items The menu items, sorted by each menu item's menu order.
614 * @param int $depth Depth of the item in reference to parents.
615 * @param stdClass $args An object containing wp_nav_menu() arguments.
616 * @return string The HTML list content for the menu items.
617 */
618function walk_nav_menu_tree( $items, $depth, $args ) {
619 $walker = ( empty( $args->walker ) ) ? new Walker_Nav_Menu() : $args->walker;
620
621 return $walker->walk( $items, $depth, $args );
622}
623
624/**
625 * Prevents a menu item ID from being used more than once.
626 *
627 * @since 3.0.1
628 * @access private
629 *
630 * @param string $id
631 * @param object $item
632 * @return string
633 */
634function _nav_menu_item_id_use_once( $id, $item ) {
635 static $_used_ids = array();
636
637 if ( in_array( $item->ID, $_used_ids, true ) ) {
638 return '';
639 }
640
641 $_used_ids[] = $item->ID;
642
643 return $id;
644}
645
646/**
647 * Remove the `menu-item-has-children` class from bottom level menu items.
648 *
649 * This runs on the {@see 'nav_menu_css_class'} filter. The $args and $depth
650 * parameters were added after the filter was originally introduced in
651 * WordPress 3.0.0 so this needs to allow for cases in which the filter is
652 * called without them.
653 *
654 * @see https://core.trac.wordpress.org/ticket/56926
655 *
656 * @since 6.2.0
657 *
658 * @param string[] $classes Array of the CSS classes that are applied to the menu item's `<li>` element.
659 * @param WP_Post $menu_item The current menu item object.
660 * @param stdClass|false $args An object of wp_nav_menu() arguments. Default false ($args unspecified when filter is called).
661 * @param int|false $depth Depth of menu item. Default false ($depth unspecified when filter is called).
662 * @return string[] Modified nav menu classes.
663 */
664function wp_nav_menu_remove_menu_item_has_children_class( $classes, $menu_item, $args = false, $depth = false ) {
665 /*
666 * Account for the filter being called without the $args or $depth parameters.
667 *
668 * This occurs when a theme uses a custom walker calling the `nav_menu_css_class`
669 * filter using the legacy formats prior to the introduction of the $args and
670 * $depth parameters.
671 *
672 * As both of these parameters are required for this function to determine
673 * both the current and maximum depth of the menu tree, the function does not
674 * attempt to remove the `menu-item-has-children` class if these parameters
675 * are not set.
676 */
677 if ( false === $depth || false === $args ) {
678 return $classes;
679 }
680
681 // Max-depth is 1-based.
682 $max_depth = isset( $args->depth ) ? (int) $args->depth : 0;
683 // Depth is 0-based so needs to be increased by one.
684 $depth = $depth + 1;
685
686 // Complete menu tree is displayed.
687 if ( 0 === $max_depth ) {
688 return $classes;
689 }
690
691 /*
692 * Remove the `menu-item-has-children` class from bottom level menu items.
693 * -1 is used to display all menu items in one level so the class should
694 * be removed from all menu items.
695 */
696 if ( -1 === $max_depth || $depth >= $max_depth ) {
697 $classes = array_diff( $classes, array( 'menu-item-has-children' ) );
698 }
699
700 return $classes;
701}
702