jetpack / class.jetpack-gutenberg.php

class.jetpack-gutenberg.php in Jetpack – WP Security, Backup, Speed, & Growth 7.8, at class.jetpack-gutenberg.php

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1	<?php //phpcs:ignore WordPress.Files.FileName.InvalidClassFileName
2	/**
3	* Handles server-side registration and use of all blocks and plugins available in Jetpack for the block editor, aka Gutenberg.
4	* Works in tandem with client-side block registration via `index.json`
5	*
6	* @package Jetpack
7	*/
8
9	use Automattic\Jetpack\Constants;
10
11	/**
12	* Wrapper function to safely register a gutenberg block type
13	*
14	* @param string $slug Slug of the block.
15	* @param array $args Arguments that are passed into register_block_type.
16	*
17	* @see register_block_type
18	*
19	* @since 6.7.0
20	*
21	* @return WP_Block_Type\|false The registered block type on success, or false on failure.
22	*/
23	function jetpack_register_block( $slug, $args = array() ) {
24	if ( 0 !== strpos( $slug, 'jetpack/' ) && ! strpos( $slug, '/' ) ) {
25	_doing_it_wrong( 'jetpack_register_block', 'Prefix the block with jetpack/ ', '7.1.0' );
26	$slug = 'jetpack/' . $slug;
27	}
28
29	// Checking whether block is registered to ensure it isn't registered twice.
30	if ( Jetpack_Gutenberg::is_registered( $slug ) ) {
31	return false;
32	}
33
34	return register_block_type( $slug, $args );
35	}
36
37	/**
38	* Helper function to register a Jetpack Gutenberg plugin
39	*
40	* @deprecated 7.1.0 Use Jetpack_Gutenberg::set_extension_available() instead
41	*
42	* @param string $slug Slug of the plugin.
43	*
44	* @since 6.9.0
45	*
46	* @return void
47	*/
48	function jetpack_register_plugin( $slug ) {
49	_deprecated_function( __FUNCTION__, '7.1', 'Jetpack_Gutenberg::set_extension_available' );
50
51	Jetpack_Gutenberg::register_plugin( $slug );
52	}
53
54	/**
55	* Set the reason why an extension (block or plugin) is unavailable
56	*
57	* @deprecated 7.1.0 Use Jetpack_Gutenberg::set_extension_unavailable() instead
58	*
59	* @param string $slug Slug of the block.
60	* @param string $reason A string representation of why the extension is unavailable.
61	*
62	* @since 7.0.0
63	*
64	* @return void
65	*/
66	function jetpack_set_extension_unavailability_reason( $slug, $reason ) {
67	_deprecated_function( __FUNCTION__, '7.1', 'Jetpack_Gutenberg::set_extension_unavailable' );
68
69	Jetpack_Gutenberg::set_extension_unavailability_reason( $slug, $reason );
70	}
71
72	/**
73	* General Gutenberg editor specific functionality
74	*/
75	class Jetpack_Gutenberg {
76
77	/**
78	* Only these extensions can be registered. Used to control availability of beta blocks.
79	*
80	* @var array Extensions whitelist
81	*/
82	private static $extensions = array();
83
84	/**
85	* Keeps track of the reasons why a given extension is unavailable.
86	*
87	* @var array Extensions availability information
88	*/
89	private static $availability = array();
90
91	/**
92	* Prepend the 'jetpack/' prefix to a block name
93	*
94	* @param string $block_name The block name.
95	*
96	* @return string The prefixed block name.
97	*/
98	private static function prepend_block_prefix( $block_name ) {
99	return 'jetpack/' . $block_name;
100	}
101
102	/**
103	* Remove the 'jetpack/' or jetpack-' prefix from an extension name
104	*
105	* @param string $extension_name The extension name.
106	*
107	* @return string The unprefixed extension name.
108	*/
109	private static function remove_extension_prefix( $extension_name ) {
110	if ( wp_startswith( $extension_name, 'jetpack/' ) \|\| wp_startswith( $extension_name, 'jetpack-' ) ) {
111	return substr( $extension_name, strlen( 'jetpack/' ) );
112	}
113	return $extension_name;
114	}
115
116	/**
117	* Whether two arrays share at least one item
118	*
119	* @param array $a An array.
120	* @param array $b Another array.
121	*
122	* @return boolean True if $a and $b share at least one item
123	*/
124	protected static function share_items( $a, $b ) {
125	return count( array_intersect( $a, $b ) ) > 0;
126	}
127
128	/**
129	* Register a block
130	*
131	* @deprecated 7.1.0 Use jetpack_register_block() instead
132	*
133	* @param string $slug Slug of the block.
134	* @param array $args Arguments that are passed into register_block_type().
135	*/
136	public static function register_block( $slug, $args ) {
137	_deprecated_function( __METHOD__, '7.1', 'jetpack_register_block' );
138
139	jetpack_register_block( 'jetpack/' . $slug, $args );
140	}
141
142	/**
143	* Register a plugin
144	*
145	* @deprecated 7.1.0 Use Jetpack_Gutenberg::set_extension_available() instead
146	*
147	* @param string $slug Slug of the plugin.
148	*/
149	public static function register_plugin( $slug ) {
150	_deprecated_function( __METHOD__, '7.1', 'Jetpack_Gutenberg::set_extension_available' );
151
152	self::set_extension_available( $slug );
153	}
154
155	/**
156	* Register a block
157	*
158	* @deprecated 7.0.0 Use jetpack_register_block() instead
159	*
160	* @param string $slug Slug of the block.
161	* @param array $args Arguments that are passed into the register_block_type.
162	* @param array $availability array containing if a block is available and the reason when it is not.
163	*/
164	public static function register( $slug, $args, $availability ) {
165	_deprecated_function( __METHOD__, '7.0', 'jetpack_register_block' );
166
167	if ( isset( $availability['available'] ) && ! $availability['available'] ) {
168	self::set_extension_unavailability_reason( $slug, $availability['unavailable_reason'] );
169	} else {
170	self::register_block( $slug, $args );
171	}
172	}
173
174	/**
175	* Set a (non-block) extension as available
176	*
177	* @param string $slug Slug of the extension.
178	*/
179	public static function set_extension_available( $slug ) {
180	self::$availability[ self::remove_extension_prefix( $slug ) ] = true;
181	}
182
183	/**
184	* Set the reason why an extension (block or plugin) is unavailable
185	*
186	* @param string $slug Slug of the extension.
187	* @param string $reason A string representation of why the extension is unavailable.
188	* @param array $details A free-form array containing more information on why the extension is unavailable.
189	*/
190	public static function set_extension_unavailable( $slug, $reason, $details = array() ) {
191	if (
192	// Extensions that require a plan may be eligible for upgrades.
193	'missing_plan' === $reason
194	/**
195	* Filter 'jetpack_block_editor_enable_upgrade_nudge' with `true` to enable or `false`
196	* to disable paid feature upgrade nudges in the block editor.
197	*
198	* @since 7.7.0
199	*
200	* @param boolean
201	*/
202	&& ! apply_filters( 'jetpack_block_editor_enable_upgrade_nudge', false )
203	) {
204	// The block editor may apply an upgrade nudge if `missing_plan` is the reason.
205	// Add a descriptive suffix to disable behavior but provide informative reason.
206	$reason .= '__nudge_disabled';
207	}
208
209	self::$availability[ self::remove_extension_prefix( $slug ) ] = array(
210	'reason' => $reason,
211	'details' => $details,
212	);
213	}
214
215	/**
216	* Set the reason why an extension (block or plugin) is unavailable
217	*
218	* @deprecated 7.1.0 Use set_extension_unavailable() instead
219	*
220	* @param string $slug Slug of the extension.
221	* @param string $reason A string representation of why the extension is unavailable.
222	*/
223	public static function set_extension_unavailability_reason( $slug, $reason ) {
224	_deprecated_function( __METHOD__, '7.1', 'Jetpack_Gutenberg::set_extension_unavailable' );
225
226	self::set_extension_unavailable( $slug, $reason );
227	}
228
229	/**
230	* Set up a whitelist of allowed block editor extensions
231	*
232	* @return void
233	*/
234	public static function init() {
235	if ( ! self::should_load() ) {
236	return;
237	}
238
239	/**
240	* Alternative to `JETPACK_BETA_BLOCKS`, set to `true` to load Beta Blocks.
241	*
242	* @since 6.9.0
243	*
244	* @param boolean
245	*/
246	if ( apply_filters( 'jetpack_load_beta_blocks', false ) ) {
247	Constants::set_constant( 'JETPACK_BETA_BLOCKS', true );
248	}
249
250	/**
251	* Filter the whitelist of block editor extensions that are available through Jetpack.
252	*
253	* @since 7.0.0
254	*
255	* @param array
256	*/
257	self::$extensions = apply_filters( 'jetpack_set_available_extensions', self::get_available_extensions() );
258
259	/**
260	* Filter the whitelist of block editor plugins that are available through Jetpack.
261	*
262	* @deprecated 7.0.0 Use jetpack_set_available_extensions instead
263	*
264	* @since 6.8.0
265	*
266	* @param array
267	*/
268	self::$extensions = apply_filters( 'jetpack_set_available_blocks', self::$extensions );
269
270	/**
271	* Filter the whitelist of block editor plugins that are available through Jetpack.
272	*
273	* @deprecated 7.0.0 Use jetpack_set_available_extensions instead
274	*
275	* @since 6.9.0
276	*
277	* @param array
278	*/
279	self::$extensions = apply_filters( 'jetpack_set_available_plugins', self::$extensions );
280	}
281
282	/**
283	* Resets the class to its original state
284	*
285	* Used in unit tests
286	*
287	* @return void
288	*/
289	public static function reset() {
290	self::$extensions = array();
291	self::$availability = array();
292	}
293
294	/**
295	* Return the Gutenberg extensions (blocks and plugins) directory
296	*
297	* @return string The Gutenberg extensions directory
298	*/
299	public static function get_blocks_directory() {
300	/**
301	* Filter to select Gutenberg blocks directory
302	*
303	* @since 6.9.0
304	*
305	* @param string default: '_inc/blocks/'
306	*/
307	return apply_filters( 'jetpack_blocks_directory', '_inc/blocks/' );
308	}
309
310	/**
311	* Checks for a given .json file in the blocks folder.
312	*
313	* @param string $preset The name of the .json file to look for.
314	*
315	* @return bool True if the file is found.
316	*/
317	public static function preset_exists( $preset ) {
318	return file_exists( JETPACK__PLUGIN_DIR . self::get_blocks_directory() . $preset . '.json' );
319	}
320
321	/**
322	* Decodes JSON loaded from a preset file in the blocks folder
323	*
324	* @param string $preset The name of the .json file to load.
325	*
326	* @return mixed Returns an object if the file is present, or false if a valid .json file is not present.
327	*/
328	public static function get_preset( $preset ) {
329	return json_decode(
330	// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
331	file_get_contents( JETPACK__PLUGIN_DIR . self::get_blocks_directory() . $preset . '.json' )
332	);
333	}
334
335	/**
336	* Returns a whitelist of Jetpack Gutenberg extensions (blocks and plugins), based on index.json
337	*
338	* @return array A list of blocks: eg [ 'publicize', 'markdown' ]
339	*/
340	public static function get_jetpack_gutenberg_extensions_whitelist() {
341	$preset_extensions_manifest = self::preset_exists( 'index' ) ? self::get_preset( 'index' ) : (object) array();
342
343	$preset_extensions = isset( $preset_extensions_manifest->production ) ? (array) $preset_extensions_manifest->production : array();
344
345	if ( Constants::is_true( 'JETPACK_BETA_BLOCKS' ) ) {
346	$beta_extensions = isset( $preset_extensions_manifest->beta ) ? (array) $preset_extensions_manifest->beta : array();
347	return array_unique( array_merge( $preset_extensions, $beta_extensions ) );
348	}
349
350	return $preset_extensions;
351	}
352
353	/**
354	* Returns a diff from a combined list of whitelisted extensions and extensions determined to be excluded
355	*
356	* @param array $whitelisted_extensions An array of whitelisted extensions.
357	*
358	* @return array A list of blocks: eg array( 'publicize', 'markdown' )
359	*/
360	public static function get_available_extensions( $whitelisted_extensions = null ) {
361	$exclusions = get_option( 'jetpack_excluded_extensions', array() );
362	$whitelisted_extensions = is_null( $whitelisted_extensions ) ? self::get_jetpack_gutenberg_extensions_whitelist() : $whitelisted_extensions;
363
364	return array_diff( $whitelisted_extensions, $exclusions );
365	}
366
367	/**
368	* Get availability of each block / plugin.
369	*
370	* @return array A list of block and plugins and their availablity status
371	*/
372	public static function get_availability() {
373	/**
374	* Fires before Gutenberg extensions availability is computed.
375	*
376	* In the function call you supply, use `jetpack_register_block()` to set a block as available.
377	* Alternatively, use `Jetpack_Gutenberg::set_extension_available()` (for a non-block plugin), and
378	* `Jetpack_Gutenberg::set_extension_unavailable()` (if the block or plugin should not be registered
379	* but marked as unavailable).
380	*
381	* @since 7.0.0
382	*/
383	do_action( 'jetpack_register_gutenberg_extensions' );
384
385	$available_extensions = array();
386
387	foreach ( self::$extensions as $extension ) {
388	$is_available = self::is_registered( 'jetpack/' . $extension ) \|\|
389	( isset( self::$availability[ $extension ] ) && true === self::$availability[ $extension ] );
390
391	$available_extensions[ $extension ] = array(
392	'available' => $is_available,
393	);
394
395	if ( ! $is_available ) {
396	$reason = isset( self::$availability[ $extension ] ) ? self::$availability[ $extension ]['reason'] : 'missing_module';
397	$details = isset( self::$availability[ $extension ] ) ? self::$availability[ $extension ]['details'] : array();
398	$available_extensions[ $extension ]['unavailable_reason'] = $reason;
399	$available_extensions[ $extension ]['details'] = $details;
400	}
401	}
402
403	return $available_extensions;
404	}
405
406	/**
407	* Check if an extension/block is already registered
408	*
409	* @since 7.2
410	*
411	* @param string $slug Name of extension/block to check.
412	*
413	* @return bool
414	*/
415	public static function is_registered( $slug ) {
416	return WP_Block_Type_Registry::get_instance()->is_registered( $slug );
417	}
418
419	/**
420	* Check if Gutenberg editor is available
421	*
422	* @since 6.7.0
423	*
424	* @return bool
425	*/
426	public static function is_gutenberg_available() {
427	return true;
428	}
429
430	/**
431	* Check whether conditions indicate Gutenberg Extensions (blocks and plugins) should be loaded
432	*
433	* Loading blocks and plugins is enabled by default and may be disabled via filter:
434	* add_filter( 'jetpack_gutenberg', '__return_false' );
435	*
436	* @since 6.9.0
437	*
438	* @return bool
439	*/
440	public static function should_load() {
441	if ( ! Jetpack::is_active() && ! Jetpack::is_development_mode() ) {
442	return false;
443	}
444
445	/**
446	* Filter to disable Gutenberg blocks
447	*
448	* @since 6.5.0
449	*
450	* @param bool true Whether to load Gutenberg blocks
451	*/
452	return (bool) apply_filters( 'jetpack_gutenberg', true );
453	}
454
455	/**
456	* Only enqueue block assets when needed.
457	*
458	* @param string $type Slug of the block.
459	* @param array $script_dependencies Script dependencies. Will be merged with automatically
460	* detected script dependencies from the webpack build.
461	*
462	* @return void
463	*/
464	public static function load_assets_as_required( $type, $script_dependencies = array() ) {
465	if ( is_admin() ) {
466	// A block's view assets will not be required in wp-admin.
467	return;
468	}
469
470	$type = sanitize_title_with_dashes( $type );
471	self::load_styles_as_required( $type );
472	self::load_scripts_as_required( $type, $script_dependencies );
473	}
474
475	/**
476	* Only enqueue block sytles when needed.
477	*
478	* @param string $type Slug of the block.
479	*
480	* @since 7.2.0
481	*
482	* @return void
483	*/
484	public static function load_styles_as_required( $type ) {
485	if ( is_admin() ) {
486	// A block's view assets will not be required in wp-admin.
487	return;
488	}
489
490	// Enqueue styles.
491	$style_relative_path = self::get_blocks_directory() . $type . '/view' . ( is_rtl() ? '.rtl' : '' ) . '.css';
492	if ( self::block_has_asset( $style_relative_path ) ) {
493	$style_version = self::get_asset_version( $style_relative_path );
494	$view_style = plugins_url( $style_relative_path, JETPACK__PLUGIN_FILE );
495	wp_enqueue_style( 'jetpack-block-' . $type, $view_style, array(), $style_version );
496	}
497
498	}
499
500	/**
501	* Only enqueue block scripts when needed.
502	*
503	* @param string $type Slug of the block.
504	* @param array $dependencies Script dependencies. Will be merged with automatically
505	* detected script dependencies from the webpack build.
506	*
507	* @since 7.2.0
508	*
509	* @return void
510	*/
511	public static function load_scripts_as_required( $type, $dependencies = array() ) {
512	if ( is_admin() ) {
513	// A block's view assets will not be required in wp-admin.
514	return;
515	}
516
517	// Enqueue script.
518	$script_relative_path = self::get_blocks_directory() . $type . '/view.js';
519	$script_deps_path = JETPACK__PLUGIN_DIR . self::get_blocks_directory() . $type . '/view.deps.json';
520
521	$script_dependencies = file_exists( $script_deps_path )
522	// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
523	? json_decode( file_get_contents( $script_deps_path ) )
524	: array();
525	$script_dependencies = array_merge( $script_dependencies, $dependencies, array( 'wp-polyfill' ) );
526
527	if ( ( ! class_exists( 'Jetpack_AMP_Support' ) \|\| ! Jetpack_AMP_Support::is_amp_request() ) && self::block_has_asset( $script_relative_path ) ) {
528	$script_version = self::get_asset_version( $script_relative_path );
529	$view_script = plugins_url( $script_relative_path, JETPACK__PLUGIN_FILE );
530	wp_enqueue_script( 'jetpack-block-' . $type, $view_script, $script_dependencies, $script_version, false );
531	}
532
533	wp_localize_script(
534	'jetpack-block-' . $type,
535	'Jetpack_Block_Assets_Base_Url',
536	plugins_url( self::get_blocks_directory(), JETPACK__PLUGIN_FILE )
537	);
538	}
539
540	/**
541	* Check if an asset exists for a block.
542	*
543	* @param string $file Path of the file we are looking for.
544	*
545	* @return bool $block_has_asset Does the file exist.
546	*/
547	public static function block_has_asset( $file ) {
548	return file_exists( JETPACK__PLUGIN_DIR . $file );
549	}
550
551	/**
552	* Get the version number to use when loading the file. Allows us to bypass cache when developing.
553	*
554	* @param string $file Path of the file we are looking for.
555	*
556	* @return string $script_version Version number.
557	*/
558	public static function get_asset_version( $file ) {
559	return Jetpack::is_development_version() && self::block_has_asset( $file )
560	? filemtime( JETPACK__PLUGIN_DIR . $file )
561	: JETPACK__VERSION;
562	}
563
564	/**
565	* Load Gutenberg editor assets
566	*
567	* @since 6.7.0
568	*
569	* @return void
570	*/
571	public static function enqueue_block_editor_assets() {
572	if ( ! self::should_load() ) {
573	return;
574	}
575
576	// Required for Analytics. See _inc/lib/admin-pages/class.jetpack-admin-page.php.
577	if ( ! Jetpack::is_development_mode() && Jetpack::is_active() ) {
578	wp_enqueue_script( 'jp-tracks', '//stats.wp.com/w.js', array(), gmdate( 'YW' ), true );
579	}
580
581	$rtl = is_rtl() ? '.rtl' : '';
582	$beta = Constants::is_true( 'JETPACK_BETA_BLOCKS' ) ? '-beta' : '';
583	$blocks_dir = self::get_blocks_directory();
584
585	$editor_script = plugins_url( "{$blocks_dir}editor{$beta}.js", JETPACK__PLUGIN_FILE );
586	$editor_style = plugins_url( "{$blocks_dir}editor{$beta}{$rtl}.css", JETPACK__PLUGIN_FILE );
587
588	$editor_deps_path = JETPACK__PLUGIN_DIR . $blocks_dir . "editor{$beta}.deps.json";
589	$editor_deps = file_exists( $editor_deps_path )
590	// phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents
591	? json_decode( file_get_contents( $editor_deps_path ) )
592	: array();
593	$editor_deps[] = 'wp-polyfill';
594
595	$version = Jetpack::is_development_version() && file_exists( JETPACK__PLUGIN_DIR . $blocks_dir . 'editor.js' )
596	? filemtime( JETPACK__PLUGIN_DIR . $blocks_dir . 'editor.js' )
597	: JETPACK__VERSION;
598
599	if ( method_exists( 'Jetpack', 'build_raw_urls' ) ) {
600	$site_fragment = Jetpack::build_raw_urls( home_url() );
601	} elseif ( class_exists( 'WPCOM_Masterbar' ) && method_exists( 'WPCOM_Masterbar', 'get_calypso_site_slug' ) ) {
602	$site_fragment = WPCOM_Masterbar::get_calypso_site_slug( get_current_blog_id() );
603	} else {
604	$site_fragment = '';
605	}
606
607	wp_enqueue_script(
608	'jetpack-blocks-editor',
609	$editor_script,
610	$editor_deps,
611	$version,
612	false
613	);
614
615	wp_localize_script(
616	'jetpack-blocks-editor',
617	'Jetpack_Block_Assets_Base_Url',
618	plugins_url( $blocks_dir . '/', JETPACK__PLUGIN_FILE )
619	);
620
621	if ( defined( 'IS_WPCOM' ) && IS_WPCOM ) {
622	$user = wp_get_current_user();
623	$user_data = array(
624	'userid' => $user->ID,
625	'username' => $user->user_login,
626	);
627	$blog_id = get_current_blog_id();
628	} else {
629	$user_data = Jetpack_Tracks_Client::get_connected_user_tracks_identity();
630	$blog_id = Jetpack_Options::get_option( 'id', 0 );
631	}
632
633	wp_localize_script(
634	'jetpack-blocks-editor',
635	'Jetpack_Editor_Initial_State',
636	array(
637	'available_blocks' => self::get_availability(),
638	'jetpack' => array( 'is_active' => Jetpack::is_active() ),
639	'siteFragment' => $site_fragment,
640	'tracksUserData' => $user_data,
641	'wpcomBlogId' => $blog_id,
642	)
643	);
644
645	wp_set_script_translations( 'jetpack-blocks-editor', 'jetpack' );
646
647	wp_enqueue_style( 'jetpack-blocks-editor', $editor_style, array(), $version );
648	}
649
650	/**
651	* Some blocks do not depend on a specific module,
652	* and can consequently be loaded outside of the usual modules.
653	* We will look for such modules in the extensions/ directory.
654	*
655	* @since 7.1.0
656	*/
657	public static function load_independent_blocks() {
658	if ( self::should_load() ) {
659	/**
660	* Look for files that match our list of available Jetpack Gutenberg extensions (blocks and plugins).
661	* If available, load them.
662	*/
663	foreach ( self::$extensions as $extension ) {
664	$extension_file_glob = glob( JETPACK__PLUGIN_DIR . 'extensions/*/' . $extension . '/' . $extension . '.php' );
665	if ( ! empty( $extension_file_glob ) ) {
666	include_once $extension_file_glob[0];
667	}
668	}
669	}
670	}
671
672	/**
673	* Get CSS classes for a block.
674	*
675	* @since 7.7.0
676	*
677	* @param string $slug Block slug.
678	* @param array $attr Block attributes.
679	* @param array $extra Potential extra classes you may want to provide.
680	*
681	* @return string $classes List of CSS classes for a block.
682	*/
683	public static function block_classes( $slug = '', $attr, $extra = array() ) {
684	if ( empty( $slug ) ) {
685	return '';
686	}
687
688	// Basic block name class.
689	$classes = array(
690	'wp-block-jetpack-' . $slug,
691	);
692
693	// Add alignment if provided.
694	if (
695	! empty( $attr['align'] )
696	&& in_array( $attr['align'], array( 'left', 'center', 'right', 'wide', 'full' ), true )
697	) {
698	array_push( $classes, 'align' . $attr['align'] );
699	}
700
701	// Add custom classes if provided in the block editor.
702	if ( ! empty( $attr['className'] ) ) {
703	array_push( $classes, $attr['className'] );
704	}
705
706	// Add any extra classes.
707	if ( is_array( $extra ) && ! empty( $extra ) ) {
708	$classes = array_merge( $classes, $extra );
709	}
710
711	return implode( $classes, ' ' );
712	}
713	}
714