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class-wp-theme.php (51308B)


      1 <?php
      2 /**
      3  * WP_Theme Class
      4  *
      5  * @package WordPress
      6  * @subpackage Theme
      7  * @since 3.4.0
      8  */
      9 final class WP_Theme implements ArrayAccess {
     10 
     11 	/**
     12 	 * Whether the theme has been marked as updateable.
     13 	 *
     14 	 * @since 4.4.0
     15 	 * @var bool
     16 	 *
     17 	 * @see WP_MS_Themes_List_Table
     18 	 */
     19 	public $update = false;
     20 
     21 	/**
     22 	 * Headers for style.css files.
     23 	 *
     24 	 * @since 3.4.0
     25 	 * @since 5.4.0 Added `Requires at least` and `Requires PHP` headers.
     26 	 * @var array
     27 	 */
     28 	private static $file_headers = array(
     29 		'Name'        => 'Theme Name',
     30 		'ThemeURI'    => 'Theme URI',
     31 		'Description' => 'Description',
     32 		'Author'      => 'Author',
     33 		'AuthorURI'   => 'Author URI',
     34 		'Version'     => 'Version',
     35 		'Template'    => 'Template',
     36 		'Status'      => 'Status',
     37 		'Tags'        => 'Tags',
     38 		'TextDomain'  => 'Text Domain',
     39 		'DomainPath'  => 'Domain Path',
     40 		'RequiresWP'  => 'Requires at least',
     41 		'RequiresPHP' => 'Requires PHP',
     42 	);
     43 
     44 	/**
     45 	 * Default themes.
     46 	 *
     47 	 * @var array
     48 	 */
     49 	private static $default_themes = array(
     50 		'classic'         => 'WordPress Classic',
     51 		'default'         => 'WordPress Default',
     52 		'twentyten'       => 'Twenty Ten',
     53 		'twentyeleven'    => 'Twenty Eleven',
     54 		'twentytwelve'    => 'Twenty Twelve',
     55 		'twentythirteen'  => 'Twenty Thirteen',
     56 		'twentyfourteen'  => 'Twenty Fourteen',
     57 		'twentyfifteen'   => 'Twenty Fifteen',
     58 		'twentysixteen'   => 'Twenty Sixteen',
     59 		'twentyseventeen' => 'Twenty Seventeen',
     60 		'twentynineteen'  => 'Twenty Nineteen',
     61 		'twentytwenty'    => 'Twenty Twenty',
     62 		'twentytwentyone' => 'Twenty Twenty-One',
     63 	);
     64 
     65 	/**
     66 	 * Renamed theme tags.
     67 	 *
     68 	 * @var array
     69 	 */
     70 	private static $tag_map = array(
     71 		'fixed-width'    => 'fixed-layout',
     72 		'flexible-width' => 'fluid-layout',
     73 	);
     74 
     75 	/**
     76 	 * Absolute path to the theme root, usually wp-content/themes
     77 	 *
     78 	 * @var string
     79 	 */
     80 	private $theme_root;
     81 
     82 	/**
     83 	 * Header data from the theme's style.css file.
     84 	 *
     85 	 * @var array
     86 	 */
     87 	private $headers = array();
     88 
     89 	/**
     90 	 * Header data from the theme's style.css file after being sanitized.
     91 	 *
     92 	 * @var array
     93 	 */
     94 	private $headers_sanitized;
     95 
     96 	/**
     97 	 * Header name from the theme's style.css after being translated.
     98 	 *
     99 	 * Cached due to sorting functions running over the translated name.
    100 	 *
    101 	 * @var string
    102 	 */
    103 	private $name_translated;
    104 
    105 	/**
    106 	 * Errors encountered when initializing the theme.
    107 	 *
    108 	 * @var WP_Error
    109 	 */
    110 	private $errors;
    111 
    112 	/**
    113 	 * The directory name of the theme's files, inside the theme root.
    114 	 *
    115 	 * In the case of a child theme, this is directory name of the child theme.
    116 	 * Otherwise, 'stylesheet' is the same as 'template'.
    117 	 *
    118 	 * @var string
    119 	 */
    120 	private $stylesheet;
    121 
    122 	/**
    123 	 * The directory name of the theme's files, inside the theme root.
    124 	 *
    125 	 * In the case of a child theme, this is the directory name of the parent theme.
    126 	 * Otherwise, 'template' is the same as 'stylesheet'.
    127 	 *
    128 	 * @var string
    129 	 */
    130 	private $template;
    131 
    132 	/**
    133 	 * A reference to the parent theme, in the case of a child theme.
    134 	 *
    135 	 * @var WP_Theme
    136 	 */
    137 	private $parent;
    138 
    139 	/**
    140 	 * URL to the theme root, usually an absolute URL to wp-content/themes
    141 	 *
    142 	 * @var string
    143 	 */
    144 	private $theme_root_uri;
    145 
    146 	/**
    147 	 * Flag for whether the theme's textdomain is loaded.
    148 	 *
    149 	 * @var bool
    150 	 */
    151 	private $textdomain_loaded;
    152 
    153 	/**
    154 	 * Stores an md5 hash of the theme root, to function as the cache key.
    155 	 *
    156 	 * @var string
    157 	 */
    158 	private $cache_hash;
    159 
    160 	/**
    161 	 * Flag for whether the themes cache bucket should be persistently cached.
    162 	 *
    163 	 * Default is false. Can be set with the {@see 'wp_cache_themes_persistently'} filter.
    164 	 *
    165 	 * @var bool
    166 	 */
    167 	private static $persistently_cache;
    168 
    169 	/**
    170 	 * Expiration time for the themes cache bucket.
    171 	 *
    172 	 * By default the bucket is not cached, so this value is useless.
    173 	 *
    174 	 * @var bool
    175 	 */
    176 	private static $cache_expiration = 1800;
    177 
    178 	/**
    179 	 * Constructor for WP_Theme.
    180 	 *
    181 	 * @since 3.4.0
    182 	 *
    183 	 * @global array $wp_theme_directories
    184 	 *
    185 	 * @param string        $theme_dir  Directory of the theme within the theme_root.
    186 	 * @param string        $theme_root Theme root.
    187 	 * @param WP_Theme|null $_child If this theme is a parent theme, the child may be passed for validation purposes.
    188 	 */
    189 	public function __construct( $theme_dir, $theme_root, $_child = null ) {
    190 		global $wp_theme_directories;
    191 
    192 		// Initialize caching on first run.
    193 		if ( ! isset( self::$persistently_cache ) ) {
    194 			/** This action is documented in wp-includes/theme.php */
    195 			self::$persistently_cache = apply_filters( 'wp_cache_themes_persistently', false, 'WP_Theme' );
    196 			if ( self::$persistently_cache ) {
    197 				wp_cache_add_global_groups( 'themes' );
    198 				if ( is_int( self::$persistently_cache ) ) {
    199 					self::$cache_expiration = self::$persistently_cache;
    200 				}
    201 			} else {
    202 				wp_cache_add_non_persistent_groups( 'themes' );
    203 			}
    204 		}
    205 
    206 		$this->theme_root = $theme_root;
    207 		$this->stylesheet = $theme_dir;
    208 
    209 		// Correct a situation where the theme is 'some-directory/some-theme' but 'some-directory' was passed in as part of the theme root instead.
    210 		if ( ! in_array( $theme_root, (array) $wp_theme_directories, true )
    211 			&& in_array( dirname( $theme_root ), (array) $wp_theme_directories, true )
    212 		) {
    213 			$this->stylesheet = basename( $this->theme_root ) . '/' . $this->stylesheet;
    214 			$this->theme_root = dirname( $theme_root );
    215 		}
    216 
    217 		$this->cache_hash = md5( $this->theme_root . '/' . $this->stylesheet );
    218 		$theme_file       = $this->stylesheet . '/style.css';
    219 
    220 		$cache = $this->cache_get( 'theme' );
    221 
    222 		if ( is_array( $cache ) ) {
    223 			foreach ( array( 'errors', 'headers', 'template' ) as $key ) {
    224 				if ( isset( $cache[ $key ] ) ) {
    225 					$this->$key = $cache[ $key ];
    226 				}
    227 			}
    228 			if ( $this->errors ) {
    229 				return;
    230 			}
    231 			if ( isset( $cache['theme_root_template'] ) ) {
    232 				$theme_root_template = $cache['theme_root_template'];
    233 			}
    234 		} elseif ( ! file_exists( $this->theme_root . '/' . $theme_file ) ) {
    235 			$this->headers['Name'] = $this->stylesheet;
    236 			if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet ) ) {
    237 				$this->errors = new WP_Error(
    238 					'theme_not_found',
    239 					sprintf(
    240 						/* translators: %s: Theme directory name. */
    241 						__( 'The theme directory "%s" does not exist.' ),
    242 						esc_html( $this->stylesheet )
    243 					)
    244 				);
    245 			} else {
    246 				$this->errors = new WP_Error( 'theme_no_stylesheet', __( 'Stylesheet is missing.' ) );
    247 			}
    248 			$this->template = $this->stylesheet;
    249 			$this->cache_add(
    250 				'theme',
    251 				array(
    252 					'headers'    => $this->headers,
    253 					'errors'     => $this->errors,
    254 					'stylesheet' => $this->stylesheet,
    255 					'template'   => $this->template,
    256 				)
    257 			);
    258 			if ( ! file_exists( $this->theme_root ) ) { // Don't cache this one.
    259 				$this->errors->add( 'theme_root_missing', __( 'Error: The themes directory is either empty or doesn&#8217;t exist. Please check your installation.' ) );
    260 			}
    261 			return;
    262 		} elseif ( ! is_readable( $this->theme_root . '/' . $theme_file ) ) {
    263 			$this->headers['Name'] = $this->stylesheet;
    264 			$this->errors          = new WP_Error( 'theme_stylesheet_not_readable', __( 'Stylesheet is not readable.' ) );
    265 			$this->template        = $this->stylesheet;
    266 			$this->cache_add(
    267 				'theme',
    268 				array(
    269 					'headers'    => $this->headers,
    270 					'errors'     => $this->errors,
    271 					'stylesheet' => $this->stylesheet,
    272 					'template'   => $this->template,
    273 				)
    274 			);
    275 			return;
    276 		} else {
    277 			$this->headers = get_file_data( $this->theme_root . '/' . $theme_file, self::$file_headers, 'theme' );
    278 			// Default themes always trump their pretenders.
    279 			// Properly identify default themes that are inside a directory within wp-content/themes.
    280 			$default_theme_slug = array_search( $this->headers['Name'], self::$default_themes, true );
    281 			if ( $default_theme_slug ) {
    282 				if ( basename( $this->stylesheet ) != $default_theme_slug ) {
    283 					$this->headers['Name'] .= '/' . $this->stylesheet;
    284 				}
    285 			}
    286 		}
    287 
    288 		if ( ! $this->template && $this->stylesheet === $this->headers['Template'] ) {
    289 			$this->errors = new WP_Error(
    290 				'theme_child_invalid',
    291 				sprintf(
    292 					/* translators: %s: Template. */
    293 					__( 'The theme defines itself as its parent theme. Please check the %s header.' ),
    294 					'<code>Template</code>'
    295 				)
    296 			);
    297 			$this->cache_add(
    298 				'theme',
    299 				array(
    300 					'headers'    => $this->headers,
    301 					'errors'     => $this->errors,
    302 					'stylesheet' => $this->stylesheet,
    303 				)
    304 			);
    305 
    306 			return;
    307 		}
    308 
    309 		// (If template is set from cache [and there are no errors], we know it's good.)
    310 		if ( ! $this->template ) {
    311 			$this->template = $this->headers['Template'];
    312 		}
    313 
    314 		if ( ! $this->template ) {
    315 			$this->template = $this->stylesheet;
    316 			if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet . '/index.php' ) ) {
    317 				$error_message = sprintf(
    318 					/* translators: 1: index.php, 2: Documentation URL, 3: style.css */
    319 					__( 'Template is missing. Standalone themes need to have a %1$s template file. <a href="%2$s">Child themes</a> need to have a Template header in the %3$s stylesheet.' ),
    320 					'<code>index.php</code>',
    321 					__( 'https://developer.wordpress.org/themes/advanced-topics/child-themes/' ),
    322 					'<code>style.css</code>'
    323 				);
    324 				$this->errors = new WP_Error( 'theme_no_index', $error_message );
    325 				$this->cache_add(
    326 					'theme',
    327 					array(
    328 						'headers'    => $this->headers,
    329 						'errors'     => $this->errors,
    330 						'stylesheet' => $this->stylesheet,
    331 						'template'   => $this->template,
    332 					)
    333 				);
    334 				return;
    335 			}
    336 		}
    337 
    338 		// If we got our data from cache, we can assume that 'template' is pointing to the right place.
    339 		if ( ! is_array( $cache ) && $this->template != $this->stylesheet && ! file_exists( $this->theme_root . '/' . $this->template . '/index.php' ) ) {
    340 			// If we're in a directory of themes inside /themes, look for the parent nearby.
    341 			// wp-content/themes/directory-of-themes/*
    342 			$parent_dir  = dirname( $this->stylesheet );
    343 			$directories = search_theme_directories();
    344 
    345 			if ( '.' !== $parent_dir && file_exists( $this->theme_root . '/' . $parent_dir . '/' . $this->template . '/index.php' ) ) {
    346 				$this->template = $parent_dir . '/' . $this->template;
    347 			} elseif ( $directories && isset( $directories[ $this->template ] ) ) {
    348 				// Look for the template in the search_theme_directories() results, in case it is in another theme root.
    349 				// We don't look into directories of themes, just the theme root.
    350 				$theme_root_template = $directories[ $this->template ]['theme_root'];
    351 			} else {
    352 				// Parent theme is missing.
    353 				$this->errors = new WP_Error(
    354 					'theme_no_parent',
    355 					sprintf(
    356 						/* translators: %s: Theme directory name. */
    357 						__( 'The parent theme is missing. Please install the "%s" parent theme.' ),
    358 						esc_html( $this->template )
    359 					)
    360 				);
    361 				$this->cache_add(
    362 					'theme',
    363 					array(
    364 						'headers'    => $this->headers,
    365 						'errors'     => $this->errors,
    366 						'stylesheet' => $this->stylesheet,
    367 						'template'   => $this->template,
    368 					)
    369 				);
    370 				$this->parent = new WP_Theme( $this->template, $this->theme_root, $this );
    371 				return;
    372 			}
    373 		}
    374 
    375 		// Set the parent, if we're a child theme.
    376 		if ( $this->template != $this->stylesheet ) {
    377 			// If we are a parent, then there is a problem. Only two generations allowed! Cancel things out.
    378 			if ( $_child instanceof WP_Theme && $_child->template == $this->stylesheet ) {
    379 				$_child->parent = null;
    380 				$_child->errors = new WP_Error(
    381 					'theme_parent_invalid',
    382 					sprintf(
    383 						/* translators: %s: Theme directory name. */
    384 						__( 'The "%s" theme is not a valid parent theme.' ),
    385 						esc_html( $_child->template )
    386 					)
    387 				);
    388 				$_child->cache_add(
    389 					'theme',
    390 					array(
    391 						'headers'    => $_child->headers,
    392 						'errors'     => $_child->errors,
    393 						'stylesheet' => $_child->stylesheet,
    394 						'template'   => $_child->template,
    395 					)
    396 				);
    397 				// The two themes actually reference each other with the Template header.
    398 				if ( $_child->stylesheet == $this->template ) {
    399 					$this->errors = new WP_Error(
    400 						'theme_parent_invalid',
    401 						sprintf(
    402 							/* translators: %s: Theme directory name. */
    403 							__( 'The "%s" theme is not a valid parent theme.' ),
    404 							esc_html( $this->template )
    405 						)
    406 					);
    407 					$this->cache_add(
    408 						'theme',
    409 						array(
    410 							'headers'    => $this->headers,
    411 							'errors'     => $this->errors,
    412 							'stylesheet' => $this->stylesheet,
    413 							'template'   => $this->template,
    414 						)
    415 					);
    416 				}
    417 				return;
    418 			}
    419 			// Set the parent. Pass the current instance so we can do the crazy checks above and assess errors.
    420 			$this->parent = new WP_Theme( $this->template, isset( $theme_root_template ) ? $theme_root_template : $this->theme_root, $this );
    421 		}
    422 
    423 		if ( wp_paused_themes()->get( $this->stylesheet ) && ( ! is_wp_error( $this->errors ) || ! isset( $this->errors->errors['theme_paused'] ) ) ) {
    424 			$this->errors = new WP_Error( 'theme_paused', __( 'This theme failed to load properly and was paused within the admin backend.' ) );
    425 		}
    426 
    427 		// We're good. If we didn't retrieve from cache, set it.
    428 		if ( ! is_array( $cache ) ) {
    429 			$cache = array(
    430 				'headers'    => $this->headers,
    431 				'errors'     => $this->errors,
    432 				'stylesheet' => $this->stylesheet,
    433 				'template'   => $this->template,
    434 			);
    435 			// If the parent theme is in another root, we'll want to cache this. Avoids an entire branch of filesystem calls above.
    436 			if ( isset( $theme_root_template ) ) {
    437 				$cache['theme_root_template'] = $theme_root_template;
    438 			}
    439 			$this->cache_add( 'theme', $cache );
    440 		}
    441 	}
    442 
    443 	/**
    444 	 * When converting the object to a string, the theme name is returned.
    445 	 *
    446 	 * @since 3.4.0
    447 	 *
    448 	 * @return string Theme name, ready for display (translated)
    449 	 */
    450 	public function __toString() {
    451 		return (string) $this->display( 'Name' );
    452 	}
    453 
    454 	/**
    455 	 * __isset() magic method for properties formerly returned by current_theme_info()
    456 	 *
    457 	 * @since 3.4.0
    458 	 *
    459 	 * @param string $offset Property to check if set.
    460 	 * @return bool Whether the given property is set.
    461 	 */
    462 	public function __isset( $offset ) {
    463 		static $properties = array(
    464 			'name',
    465 			'title',
    466 			'version',
    467 			'parent_theme',
    468 			'template_dir',
    469 			'stylesheet_dir',
    470 			'template',
    471 			'stylesheet',
    472 			'screenshot',
    473 			'description',
    474 			'author',
    475 			'tags',
    476 			'theme_root',
    477 			'theme_root_uri',
    478 		);
    479 
    480 		return in_array( $offset, $properties, true );
    481 	}
    482 
    483 	/**
    484 	 * __get() magic method for properties formerly returned by current_theme_info()
    485 	 *
    486 	 * @since 3.4.0
    487 	 *
    488 	 * @param string $offset Property to get.
    489 	 * @return mixed Property value.
    490 	 */
    491 	public function __get( $offset ) {
    492 		switch ( $offset ) {
    493 			case 'name':
    494 			case 'title':
    495 				return $this->get( 'Name' );
    496 			case 'version':
    497 				return $this->get( 'Version' );
    498 			case 'parent_theme':
    499 				return $this->parent() ? $this->parent()->get( 'Name' ) : '';
    500 			case 'template_dir':
    501 				return $this->get_template_directory();
    502 			case 'stylesheet_dir':
    503 				return $this->get_stylesheet_directory();
    504 			case 'template':
    505 				return $this->get_template();
    506 			case 'stylesheet':
    507 				return $this->get_stylesheet();
    508 			case 'screenshot':
    509 				return $this->get_screenshot( 'relative' );
    510 			// 'author' and 'description' did not previously return translated data.
    511 			case 'description':
    512 				return $this->display( 'Description' );
    513 			case 'author':
    514 				return $this->display( 'Author' );
    515 			case 'tags':
    516 				return $this->get( 'Tags' );
    517 			case 'theme_root':
    518 				return $this->get_theme_root();
    519 			case 'theme_root_uri':
    520 				return $this->get_theme_root_uri();
    521 			// For cases where the array was converted to an object.
    522 			default:
    523 				return $this->offsetGet( $offset );
    524 		}
    525 	}
    526 
    527 	/**
    528 	 * Method to implement ArrayAccess for keys formerly returned by get_themes()
    529 	 *
    530 	 * @since 3.4.0
    531 	 *
    532 	 * @param mixed $offset
    533 	 * @param mixed $value
    534 	 */
    535 	public function offsetSet( $offset, $value ) {}
    536 
    537 	/**
    538 	 * Method to implement ArrayAccess for keys formerly returned by get_themes()
    539 	 *
    540 	 * @since 3.4.0
    541 	 *
    542 	 * @param mixed $offset
    543 	 */
    544 	public function offsetUnset( $offset ) {}
    545 
    546 	/**
    547 	 * Method to implement ArrayAccess for keys formerly returned by get_themes()
    548 	 *
    549 	 * @since 3.4.0
    550 	 *
    551 	 * @param mixed $offset
    552 	 * @return bool
    553 	 */
    554 	public function offsetExists( $offset ) {
    555 		static $keys = array(
    556 			'Name',
    557 			'Version',
    558 			'Status',
    559 			'Title',
    560 			'Author',
    561 			'Author Name',
    562 			'Author URI',
    563 			'Description',
    564 			'Template',
    565 			'Stylesheet',
    566 			'Template Files',
    567 			'Stylesheet Files',
    568 			'Template Dir',
    569 			'Stylesheet Dir',
    570 			'Screenshot',
    571 			'Tags',
    572 			'Theme Root',
    573 			'Theme Root URI',
    574 			'Parent Theme',
    575 		);
    576 
    577 		return in_array( $offset, $keys, true );
    578 	}
    579 
    580 	/**
    581 	 * Method to implement ArrayAccess for keys formerly returned by get_themes().
    582 	 *
    583 	 * Author, Author Name, Author URI, and Description did not previously return
    584 	 * translated data. We are doing so now as it is safe to do. However, as
    585 	 * Name and Title could have been used as the key for get_themes(), both remain
    586 	 * untranslated for back compatibility. This means that ['Name'] is not ideal,
    587 	 * and care should be taken to use `$theme::display( 'Name' )` to get a properly
    588 	 * translated header.
    589 	 *
    590 	 * @since 3.4.0
    591 	 *
    592 	 * @param mixed $offset
    593 	 * @return mixed
    594 	 */
    595 	public function offsetGet( $offset ) {
    596 		switch ( $offset ) {
    597 			case 'Name':
    598 			case 'Title':
    599 				/*
    600 				 * See note above about using translated data. get() is not ideal.
    601 				 * It is only for backward compatibility. Use display().
    602 				 */
    603 				return $this->get( 'Name' );
    604 			case 'Author':
    605 				return $this->display( 'Author' );
    606 			case 'Author Name':
    607 				return $this->display( 'Author', false );
    608 			case 'Author URI':
    609 				return $this->display( 'AuthorURI' );
    610 			case 'Description':
    611 				return $this->display( 'Description' );
    612 			case 'Version':
    613 			case 'Status':
    614 				return $this->get( $offset );
    615 			case 'Template':
    616 				return $this->get_template();
    617 			case 'Stylesheet':
    618 				return $this->get_stylesheet();
    619 			case 'Template Files':
    620 				return $this->get_files( 'php', 1, true );
    621 			case 'Stylesheet Files':
    622 				return $this->get_files( 'css', 0, false );
    623 			case 'Template Dir':
    624 				return $this->get_template_directory();
    625 			case 'Stylesheet Dir':
    626 				return $this->get_stylesheet_directory();
    627 			case 'Screenshot':
    628 				return $this->get_screenshot( 'relative' );
    629 			case 'Tags':
    630 				return $this->get( 'Tags' );
    631 			case 'Theme Root':
    632 				return $this->get_theme_root();
    633 			case 'Theme Root URI':
    634 				return $this->get_theme_root_uri();
    635 			case 'Parent Theme':
    636 				return $this->parent() ? $this->parent()->get( 'Name' ) : '';
    637 			default:
    638 				return null;
    639 		}
    640 	}
    641 
    642 	/**
    643 	 * Returns errors property.
    644 	 *
    645 	 * @since 3.4.0
    646 	 *
    647 	 * @return WP_Error|false WP_Error if there are errors, or false.
    648 	 */
    649 	public function errors() {
    650 		return is_wp_error( $this->errors ) ? $this->errors : false;
    651 	}
    652 
    653 	/**
    654 	 * Whether the theme exists.
    655 	 *
    656 	 * A theme with errors exists. A theme with the error of 'theme_not_found',
    657 	 * meaning that the theme's directory was not found, does not exist.
    658 	 *
    659 	 * @since 3.4.0
    660 	 *
    661 	 * @return bool Whether the theme exists.
    662 	 */
    663 	public function exists() {
    664 		return ! ( $this->errors() && in_array( 'theme_not_found', $this->errors()->get_error_codes(), true ) );
    665 	}
    666 
    667 	/**
    668 	 * Returns reference to the parent theme.
    669 	 *
    670 	 * @since 3.4.0
    671 	 *
    672 	 * @return WP_Theme|false Parent theme, or false if the current theme is not a child theme.
    673 	 */
    674 	public function parent() {
    675 		return isset( $this->parent ) ? $this->parent : false;
    676 	}
    677 
    678 	/**
    679 	 * Adds theme data to cache.
    680 	 *
    681 	 * Cache entries keyed by the theme and the type of data.
    682 	 *
    683 	 * @since 3.4.0
    684 	 *
    685 	 * @param string       $key  Type of data to store (theme, screenshot, headers, post_templates)
    686 	 * @param array|string $data Data to store
    687 	 * @return bool Return value from wp_cache_add()
    688 	 */
    689 	private function cache_add( $key, $data ) {
    690 		return wp_cache_add( $key . '-' . $this->cache_hash, $data, 'themes', self::$cache_expiration );
    691 	}
    692 
    693 	/**
    694 	 * Gets theme data from cache.
    695 	 *
    696 	 * Cache entries are keyed by the theme and the type of data.
    697 	 *
    698 	 * @since 3.4.0
    699 	 *
    700 	 * @param string $key Type of data to retrieve (theme, screenshot, headers, post_templates)
    701 	 * @return mixed Retrieved data
    702 	 */
    703 	private function cache_get( $key ) {
    704 		return wp_cache_get( $key . '-' . $this->cache_hash, 'themes' );
    705 	}
    706 
    707 	/**
    708 	 * Clears the cache for the theme.
    709 	 *
    710 	 * @since 3.4.0
    711 	 */
    712 	public function cache_delete() {
    713 		foreach ( array( 'theme', 'screenshot', 'headers', 'post_templates' ) as $key ) {
    714 			wp_cache_delete( $key . '-' . $this->cache_hash, 'themes' );
    715 		}
    716 		$this->template          = null;
    717 		$this->textdomain_loaded = null;
    718 		$this->theme_root_uri    = null;
    719 		$this->parent            = null;
    720 		$this->errors            = null;
    721 		$this->headers_sanitized = null;
    722 		$this->name_translated   = null;
    723 		$this->headers           = array();
    724 		$this->__construct( $this->stylesheet, $this->theme_root );
    725 	}
    726 
    727 	/**
    728 	 * Get a raw, unformatted theme header.
    729 	 *
    730 	 * The header is sanitized, but is not translated, and is not marked up for display.
    731 	 * To get a theme header for display, use the display() method.
    732 	 *
    733 	 * Use the get_template() method, not the 'Template' header, for finding the template.
    734 	 * The 'Template' header is only good for what was written in the style.css, while
    735 	 * get_template() takes into account where WordPress actually located the theme and
    736 	 * whether it is actually valid.
    737 	 *
    738 	 * @since 3.4.0
    739 	 *
    740 	 * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags.
    741 	 * @return string|array|false String or array (for Tags header) on success, false on failure.
    742 	 */
    743 	public function get( $header ) {
    744 		if ( ! isset( $this->headers[ $header ] ) ) {
    745 			return false;
    746 		}
    747 
    748 		if ( ! isset( $this->headers_sanitized ) ) {
    749 			$this->headers_sanitized = $this->cache_get( 'headers' );
    750 			if ( ! is_array( $this->headers_sanitized ) ) {
    751 				$this->headers_sanitized = array();
    752 			}
    753 		}
    754 
    755 		if ( isset( $this->headers_sanitized[ $header ] ) ) {
    756 			return $this->headers_sanitized[ $header ];
    757 		}
    758 
    759 		// If themes are a persistent group, sanitize everything and cache it. One cache add is better than many cache sets.
    760 		if ( self::$persistently_cache ) {
    761 			foreach ( array_keys( $this->headers ) as $_header ) {
    762 				$this->headers_sanitized[ $_header ] = $this->sanitize_header( $_header, $this->headers[ $_header ] );
    763 			}
    764 			$this->cache_add( 'headers', $this->headers_sanitized );
    765 		} else {
    766 			$this->headers_sanitized[ $header ] = $this->sanitize_header( $header, $this->headers[ $header ] );
    767 		}
    768 
    769 		return $this->headers_sanitized[ $header ];
    770 	}
    771 
    772 	/**
    773 	 * Gets a theme header, formatted and translated for display.
    774 	 *
    775 	 * @since 3.4.0
    776 	 *
    777 	 * @param string $header    Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags.
    778 	 * @param bool   $markup    Optional. Whether to mark up the header. Defaults to true.
    779 	 * @param bool   $translate Optional. Whether to translate the header. Defaults to true.
    780 	 * @return string|array|false Processed header. An array for Tags if `$markup` is false, string otherwise.
    781 	 *                            False on failure.
    782 	 */
    783 	public function display( $header, $markup = true, $translate = true ) {
    784 		$value = $this->get( $header );
    785 		if ( false === $value ) {
    786 			return false;
    787 		}
    788 
    789 		if ( $translate && ( empty( $value ) || ! $this->load_textdomain() ) ) {
    790 			$translate = false;
    791 		}
    792 
    793 		if ( $translate ) {
    794 			$value = $this->translate_header( $header, $value );
    795 		}
    796 
    797 		if ( $markup ) {
    798 			$value = $this->markup_header( $header, $value, $translate );
    799 		}
    800 
    801 		return $value;
    802 	}
    803 
    804 	/**
    805 	 * Sanitize a theme header.
    806 	 *
    807 	 * @since 3.4.0
    808 	 * @since 5.4.0 Added support for `Requires at least` and `Requires PHP` headers.
    809 	 *
    810 	 * @param string $header Theme header. Accepts 'Name', 'Description', 'Author', 'Version',
    811 	 *                       'ThemeURI', 'AuthorURI', 'Status', 'Tags', 'RequiresWP', 'RequiresPHP'.
    812 	 * @param string $value  Value to sanitize.
    813 	 * @return string|array An array for Tags header, string otherwise.
    814 	 */
    815 	private function sanitize_header( $header, $value ) {
    816 		switch ( $header ) {
    817 			case 'Status':
    818 				if ( ! $value ) {
    819 					$value = 'publish';
    820 					break;
    821 				}
    822 				// Fall through otherwise.
    823 			case 'Name':
    824 				static $header_tags = array(
    825 					'abbr'    => array( 'title' => true ),
    826 					'acronym' => array( 'title' => true ),
    827 					'code'    => true,
    828 					'em'      => true,
    829 					'strong'  => true,
    830 				);
    831 
    832 				$value = wp_kses( $value, $header_tags );
    833 				break;
    834 			case 'Author':
    835 				// There shouldn't be anchor tags in Author, but some themes like to be challenging.
    836 			case 'Description':
    837 				static $header_tags_with_a = array(
    838 					'a'       => array(
    839 						'href'  => true,
    840 						'title' => true,
    841 					),
    842 					'abbr'    => array( 'title' => true ),
    843 					'acronym' => array( 'title' => true ),
    844 					'code'    => true,
    845 					'em'      => true,
    846 					'strong'  => true,
    847 				);
    848 
    849 				$value = wp_kses( $value, $header_tags_with_a );
    850 				break;
    851 			case 'ThemeURI':
    852 			case 'AuthorURI':
    853 				$value = esc_url_raw( $value );
    854 				break;
    855 			case 'Tags':
    856 				$value = array_filter( array_map( 'trim', explode( ',', strip_tags( $value ) ) ) );
    857 				break;
    858 			case 'Version':
    859 			case 'RequiresWP':
    860 			case 'RequiresPHP':
    861 				$value = strip_tags( $value );
    862 				break;
    863 		}
    864 
    865 		return $value;
    866 	}
    867 
    868 	/**
    869 	 * Mark up a theme header.
    870 	 *
    871 	 * @since 3.4.0
    872 	 *
    873 	 * @param string       $header    Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags.
    874 	 * @param string|array $value     Value to mark up. An array for Tags header, string otherwise.
    875 	 * @param string       $translate Whether the header has been translated.
    876 	 * @return string Value, marked up.
    877 	 */
    878 	private function markup_header( $header, $value, $translate ) {
    879 		switch ( $header ) {
    880 			case 'Name':
    881 				if ( empty( $value ) ) {
    882 					$value = esc_html( $this->get_stylesheet() );
    883 				}
    884 				break;
    885 			case 'Description':
    886 				$value = wptexturize( $value );
    887 				break;
    888 			case 'Author':
    889 				if ( $this->get( 'AuthorURI' ) ) {
    890 					$value = sprintf( '<a href="%1$s">%2$s</a>', $this->display( 'AuthorURI', true, $translate ), $value );
    891 				} elseif ( ! $value ) {
    892 					$value = __( 'Anonymous' );
    893 				}
    894 				break;
    895 			case 'Tags':
    896 				static $comma = null;
    897 				if ( ! isset( $comma ) ) {
    898 					/* translators: Used between list items, there is a space after the comma. */
    899 					$comma = __( ', ' );
    900 				}
    901 				$value = implode( $comma, $value );
    902 				break;
    903 			case 'ThemeURI':
    904 			case 'AuthorURI':
    905 				$value = esc_url( $value );
    906 				break;
    907 		}
    908 
    909 		return $value;
    910 	}
    911 
    912 	/**
    913 	 * Translate a theme header.
    914 	 *
    915 	 * @since 3.4.0
    916 	 *
    917 	 * @param string       $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags.
    918 	 * @param string|array $value  Value to translate. An array for Tags header, string otherwise.
    919 	 * @return string|array Translated value. An array for Tags header, string otherwise.
    920 	 */
    921 	private function translate_header( $header, $value ) {
    922 		switch ( $header ) {
    923 			case 'Name':
    924 				// Cached for sorting reasons.
    925 				if ( isset( $this->name_translated ) ) {
    926 					return $this->name_translated;
    927 				}
    928 
    929 				// phpcs:ignore WordPress.WP.I18n.LowLevelTranslationFunction,WordPress.WP.I18n.NonSingularStringLiteralText,WordPress.WP.I18n.NonSingularStringLiteralDomain
    930 				$this->name_translated = translate( $value, $this->get( 'TextDomain' ) );
    931 
    932 				return $this->name_translated;
    933 			case 'Tags':
    934 				if ( empty( $value ) || ! function_exists( 'get_theme_feature_list' ) ) {
    935 					return $value;
    936 				}
    937 
    938 				static $tags_list;
    939 				if ( ! isset( $tags_list ) ) {
    940 					$tags_list = array(
    941 						// As of 4.6, deprecated tags which are only used to provide translation for older themes.
    942 						'black'             => __( 'Black' ),
    943 						'blue'              => __( 'Blue' ),
    944 						'brown'             => __( 'Brown' ),
    945 						'gray'              => __( 'Gray' ),
    946 						'green'             => __( 'Green' ),
    947 						'orange'            => __( 'Orange' ),
    948 						'pink'              => __( 'Pink' ),
    949 						'purple'            => __( 'Purple' ),
    950 						'red'               => __( 'Red' ),
    951 						'silver'            => __( 'Silver' ),
    952 						'tan'               => __( 'Tan' ),
    953 						'white'             => __( 'White' ),
    954 						'yellow'            => __( 'Yellow' ),
    955 						'dark'              => __( 'Dark' ),
    956 						'light'             => __( 'Light' ),
    957 						'fixed-layout'      => __( 'Fixed Layout' ),
    958 						'fluid-layout'      => __( 'Fluid Layout' ),
    959 						'responsive-layout' => __( 'Responsive Layout' ),
    960 						'blavatar'          => __( 'Blavatar' ),
    961 						'photoblogging'     => __( 'Photoblogging' ),
    962 						'seasonal'          => __( 'Seasonal' ),
    963 					);
    964 
    965 					$feature_list = get_theme_feature_list( false ); // No API.
    966 
    967 					foreach ( $feature_list as $tags ) {
    968 						$tags_list += $tags;
    969 					}
    970 				}
    971 
    972 				foreach ( $value as &$tag ) {
    973 					if ( isset( $tags_list[ $tag ] ) ) {
    974 						$tag = $tags_list[ $tag ];
    975 					} elseif ( isset( self::$tag_map[ $tag ] ) ) {
    976 						$tag = $tags_list[ self::$tag_map[ $tag ] ];
    977 					}
    978 				}
    979 
    980 				return $value;
    981 
    982 			default:
    983 				// phpcs:ignore WordPress.WP.I18n.LowLevelTranslationFunction,WordPress.WP.I18n.NonSingularStringLiteralText,WordPress.WP.I18n.NonSingularStringLiteralDomain
    984 				$value = translate( $value, $this->get( 'TextDomain' ) );
    985 		}
    986 		return $value;
    987 	}
    988 
    989 	/**
    990 	 * The directory name of the theme's "stylesheet" files, inside the theme root.
    991 	 *
    992 	 * In the case of a child theme, this is directory name of the child theme.
    993 	 * Otherwise, get_stylesheet() is the same as get_template().
    994 	 *
    995 	 * @since 3.4.0
    996 	 *
    997 	 * @return string Stylesheet
    998 	 */
    999 	public function get_stylesheet() {
   1000 		return $this->stylesheet;
   1001 	}
   1002 
   1003 	/**
   1004 	 * The directory name of the theme's "template" files, inside the theme root.
   1005 	 *
   1006 	 * In the case of a child theme, this is the directory name of the parent theme.
   1007 	 * Otherwise, the get_template() is the same as get_stylesheet().
   1008 	 *
   1009 	 * @since 3.4.0
   1010 	 *
   1011 	 * @return string Template
   1012 	 */
   1013 	public function get_template() {
   1014 		return $this->template;
   1015 	}
   1016 
   1017 	/**
   1018 	 * Returns the absolute path to the directory of a theme's "stylesheet" files.
   1019 	 *
   1020 	 * In the case of a child theme, this is the absolute path to the directory
   1021 	 * of the child theme's files.
   1022 	 *
   1023 	 * @since 3.4.0
   1024 	 *
   1025 	 * @return string Absolute path of the stylesheet directory.
   1026 	 */
   1027 	public function get_stylesheet_directory() {
   1028 		if ( $this->errors() && in_array( 'theme_root_missing', $this->errors()->get_error_codes(), true ) ) {
   1029 			return '';
   1030 		}
   1031 
   1032 		return $this->theme_root . '/' . $this->stylesheet;
   1033 	}
   1034 
   1035 	/**
   1036 	 * Returns the absolute path to the directory of a theme's "template" files.
   1037 	 *
   1038 	 * In the case of a child theme, this is the absolute path to the directory
   1039 	 * of the parent theme's files.
   1040 	 *
   1041 	 * @since 3.4.0
   1042 	 *
   1043 	 * @return string Absolute path of the template directory.
   1044 	 */
   1045 	public function get_template_directory() {
   1046 		if ( $this->parent() ) {
   1047 			$theme_root = $this->parent()->theme_root;
   1048 		} else {
   1049 			$theme_root = $this->theme_root;
   1050 		}
   1051 
   1052 		return $theme_root . '/' . $this->template;
   1053 	}
   1054 
   1055 	/**
   1056 	 * Returns the URL to the directory of a theme's "stylesheet" files.
   1057 	 *
   1058 	 * In the case of a child theme, this is the URL to the directory of the
   1059 	 * child theme's files.
   1060 	 *
   1061 	 * @since 3.4.0
   1062 	 *
   1063 	 * @return string URL to the stylesheet directory.
   1064 	 */
   1065 	public function get_stylesheet_directory_uri() {
   1066 		return $this->get_theme_root_uri() . '/' . str_replace( '%2F', '/', rawurlencode( $this->stylesheet ) );
   1067 	}
   1068 
   1069 	/**
   1070 	 * Returns the URL to the directory of a theme's "template" files.
   1071 	 *
   1072 	 * In the case of a child theme, this is the URL to the directory of the
   1073 	 * parent theme's files.
   1074 	 *
   1075 	 * @since 3.4.0
   1076 	 *
   1077 	 * @return string URL to the template directory.
   1078 	 */
   1079 	public function get_template_directory_uri() {
   1080 		if ( $this->parent() ) {
   1081 			$theme_root_uri = $this->parent()->get_theme_root_uri();
   1082 		} else {
   1083 			$theme_root_uri = $this->get_theme_root_uri();
   1084 		}
   1085 
   1086 		return $theme_root_uri . '/' . str_replace( '%2F', '/', rawurlencode( $this->template ) );
   1087 	}
   1088 
   1089 	/**
   1090 	 * The absolute path to the directory of the theme root.
   1091 	 *
   1092 	 * This is typically the absolute path to wp-content/themes.
   1093 	 *
   1094 	 * @since 3.4.0
   1095 	 *
   1096 	 * @return string Theme root.
   1097 	 */
   1098 	public function get_theme_root() {
   1099 		return $this->theme_root;
   1100 	}
   1101 
   1102 	/**
   1103 	 * Returns the URL to the directory of the theme root.
   1104 	 *
   1105 	 * This is typically the absolute URL to wp-content/themes. This forms the basis
   1106 	 * for all other URLs returned by WP_Theme, so we pass it to the public function
   1107 	 * get_theme_root_uri() and allow it to run the {@see 'theme_root_uri'} filter.
   1108 	 *
   1109 	 * @since 3.4.0
   1110 	 *
   1111 	 * @return string Theme root URI.
   1112 	 */
   1113 	public function get_theme_root_uri() {
   1114 		if ( ! isset( $this->theme_root_uri ) ) {
   1115 			$this->theme_root_uri = get_theme_root_uri( $this->stylesheet, $this->theme_root );
   1116 		}
   1117 		return $this->theme_root_uri;
   1118 	}
   1119 
   1120 	/**
   1121 	 * Returns the main screenshot file for the theme.
   1122 	 *
   1123 	 * The main screenshot is called screenshot.png. gif and jpg extensions are also allowed.
   1124 	 *
   1125 	 * Screenshots for a theme must be in the stylesheet directory. (In the case of child
   1126 	 * themes, parent theme screenshots are not inherited.)
   1127 	 *
   1128 	 * @since 3.4.0
   1129 	 *
   1130 	 * @param string $uri Type of URL to return, either 'relative' or an absolute URI. Defaults to absolute URI.
   1131 	 * @return string|false Screenshot file. False if the theme does not have a screenshot.
   1132 	 */
   1133 	public function get_screenshot( $uri = 'uri' ) {
   1134 		$screenshot = $this->cache_get( 'screenshot' );
   1135 		if ( $screenshot ) {
   1136 			if ( 'relative' === $uri ) {
   1137 				return $screenshot;
   1138 			}
   1139 			return $this->get_stylesheet_directory_uri() . '/' . $screenshot;
   1140 		} elseif ( 0 === $screenshot ) {
   1141 			return false;
   1142 		}
   1143 
   1144 		foreach ( array( 'png', 'gif', 'jpg', 'jpeg', 'webp' ) as $ext ) {
   1145 			if ( file_exists( $this->get_stylesheet_directory() . "/screenshot.$ext" ) ) {
   1146 				$this->cache_add( 'screenshot', 'screenshot.' . $ext );
   1147 				if ( 'relative' === $uri ) {
   1148 					return 'screenshot.' . $ext;
   1149 				}
   1150 				return $this->get_stylesheet_directory_uri() . '/' . 'screenshot.' . $ext;
   1151 			}
   1152 		}
   1153 
   1154 		$this->cache_add( 'screenshot', 0 );
   1155 		return false;
   1156 	}
   1157 
   1158 	/**
   1159 	 * Return files in the theme's directory.
   1160 	 *
   1161 	 * @since 3.4.0
   1162 	 *
   1163 	 * @param string[]|string $type          Optional. Array of extensions to find, string of a single extension,
   1164 	 *                                       or null for all extensions. Default null.
   1165 	 * @param int             $depth         Optional. How deep to search for files. Defaults to a flat scan (0 depth).
   1166 	 *                                       -1 depth is infinite.
   1167 	 * @param bool            $search_parent Optional. Whether to return parent files. Default false.
   1168 	 * @return string[] Array of files, keyed by the path to the file relative to the theme's directory, with the values
   1169 	 *                  being absolute paths.
   1170 	 */
   1171 	public function get_files( $type = null, $depth = 0, $search_parent = false ) {
   1172 		$files = (array) self::scandir( $this->get_stylesheet_directory(), $type, $depth );
   1173 
   1174 		if ( $search_parent && $this->parent() ) {
   1175 			$files += (array) self::scandir( $this->get_template_directory(), $type, $depth );
   1176 		}
   1177 
   1178 		return $files;
   1179 	}
   1180 
   1181 	/**
   1182 	 * Returns the theme's post templates.
   1183 	 *
   1184 	 * @since 4.7.0
   1185 	 * @since 5.8.0 Include block templates.
   1186 	 *
   1187 	 * @return string[] Array of page templates, keyed by filename and post type,
   1188 	 *                  with the value of the translated header name.
   1189 	 */
   1190 	public function get_post_templates() {
   1191 		// If you screw up your current theme and we invalidate your parent, most things still work. Let it slide.
   1192 		if ( $this->errors() && $this->errors()->get_error_codes() !== array( 'theme_parent_invalid' ) ) {
   1193 			return array();
   1194 		}
   1195 
   1196 		$post_templates = $this->cache_get( 'post_templates' );
   1197 
   1198 		if ( ! is_array( $post_templates ) ) {
   1199 			$post_templates = array();
   1200 
   1201 			$files = (array) $this->get_files( 'php', 1, true );
   1202 
   1203 			foreach ( $files as $file => $full_path ) {
   1204 				if ( ! preg_match( '|Template Name:(.*)$|mi', file_get_contents( $full_path ), $header ) ) {
   1205 					continue;
   1206 				}
   1207 
   1208 				$types = array( 'page' );
   1209 				if ( preg_match( '|Template Post Type:(.*)$|mi', file_get_contents( $full_path ), $type ) ) {
   1210 					$types = explode( ',', _cleanup_header_comment( $type[1] ) );
   1211 				}
   1212 
   1213 				foreach ( $types as $type ) {
   1214 					$type = sanitize_key( $type );
   1215 					if ( ! isset( $post_templates[ $type ] ) ) {
   1216 						$post_templates[ $type ] = array();
   1217 					}
   1218 
   1219 					$post_templates[ $type ][ $file ] = _cleanup_header_comment( $header[1] );
   1220 				}
   1221 			}
   1222 
   1223 			if ( current_theme_supports( 'block-templates' ) ) {
   1224 				$block_templates = get_block_templates( array(), 'wp_template' );
   1225 				foreach ( get_post_types( array( 'public' => true ) ) as $type ) {
   1226 					foreach ( $block_templates as $block_template ) {
   1227 						$post_templates[ $type ][ $block_template->slug ] = $block_template->title;
   1228 					}
   1229 				}
   1230 			}
   1231 
   1232 			$this->cache_add( 'post_templates', $post_templates );
   1233 		}
   1234 
   1235 		if ( $this->load_textdomain() ) {
   1236 			foreach ( $post_templates as &$post_type ) {
   1237 				foreach ( $post_type as &$post_template ) {
   1238 					$post_template = $this->translate_header( 'Template Name', $post_template );
   1239 				}
   1240 			}
   1241 		}
   1242 
   1243 		return $post_templates;
   1244 	}
   1245 
   1246 	/**
   1247 	 * Returns the theme's post templates for a given post type.
   1248 	 *
   1249 	 * @since 3.4.0
   1250 	 * @since 4.7.0 Added the `$post_type` parameter.
   1251 	 *
   1252 	 * @param WP_Post|null $post      Optional. The post being edited, provided for context.
   1253 	 * @param string       $post_type Optional. Post type to get the templates for. Default 'page'.
   1254 	 *                                If a post is provided, its post type is used.
   1255 	 * @return string[] Array of template header names keyed by the template file name.
   1256 	 */
   1257 	public function get_page_templates( $post = null, $post_type = 'page' ) {
   1258 		if ( $post ) {
   1259 			$post_type = get_post_type( $post );
   1260 		}
   1261 
   1262 		$post_templates = $this->get_post_templates();
   1263 		$post_templates = isset( $post_templates[ $post_type ] ) ? $post_templates[ $post_type ] : array();
   1264 
   1265 		/**
   1266 		 * Filters list of page templates for a theme.
   1267 		 *
   1268 		 * @since 4.9.6
   1269 		 *
   1270 		 * @param string[]     $post_templates Array of template header names keyed by the template file name.
   1271 		 * @param WP_Theme     $theme          The theme object.
   1272 		 * @param WP_Post|null $post           The post being edited, provided for context, or null.
   1273 		 * @param string       $post_type      Post type to get the templates for.
   1274 		 */
   1275 		$post_templates = (array) apply_filters( 'theme_templates', $post_templates, $this, $post, $post_type );
   1276 
   1277 		/**
   1278 		 * Filters list of page templates for a theme.
   1279 		 *
   1280 		 * The dynamic portion of the hook name, `$post_type`, refers to the post type.
   1281 		 *
   1282 		 * Possible hook names include:
   1283 		 *
   1284 		 *  - `theme_post_templates`
   1285 		 *  - `theme_page_templates`
   1286 		 *  - `theme_attachment_templates`
   1287 		 *
   1288 		 * @since 3.9.0
   1289 		 * @since 4.4.0 Converted to allow complete control over the `$page_templates` array.
   1290 		 * @since 4.7.0 Added the `$post_type` parameter.
   1291 		 *
   1292 		 * @param string[]     $post_templates Array of template header names keyed by the template file name.
   1293 		 * @param WP_Theme     $theme          The theme object.
   1294 		 * @param WP_Post|null $post           The post being edited, provided for context, or null.
   1295 		 * @param string       $post_type      Post type to get the templates for.
   1296 		 */
   1297 		$post_templates = (array) apply_filters( "theme_{$post_type}_templates", $post_templates, $this, $post, $post_type );
   1298 
   1299 		return $post_templates;
   1300 	}
   1301 
   1302 	/**
   1303 	 * Scans a directory for files of a certain extension.
   1304 	 *
   1305 	 * @since 3.4.0
   1306 	 *
   1307 	 * @param string            $path          Absolute path to search.
   1308 	 * @param array|string|null $extensions    Optional. Array of extensions to find, string of a single extension,
   1309 	 *                                         or null for all extensions. Default null.
   1310 	 * @param int               $depth         Optional. How many levels deep to search for files. Accepts 0, 1+, or
   1311 	 *                                         -1 (infinite depth). Default 0.
   1312 	 * @param string            $relative_path Optional. The basename of the absolute path. Used to control the
   1313 	 *                                         returned path for the found files, particularly when this function
   1314 	 *                                         recurses to lower depths. Default empty.
   1315 	 * @return string[]|false Array of files, keyed by the path to the file relative to the `$path` directory prepended
   1316 	 *                        with `$relative_path`, with the values being absolute paths. False otherwise.
   1317 	 */
   1318 	private static function scandir( $path, $extensions = null, $depth = 0, $relative_path = '' ) {
   1319 		if ( ! is_dir( $path ) ) {
   1320 			return false;
   1321 		}
   1322 
   1323 		if ( $extensions ) {
   1324 			$extensions  = (array) $extensions;
   1325 			$_extensions = implode( '|', $extensions );
   1326 		}
   1327 
   1328 		$relative_path = trailingslashit( $relative_path );
   1329 		if ( '/' === $relative_path ) {
   1330 			$relative_path = '';
   1331 		}
   1332 
   1333 		$results = scandir( $path );
   1334 		$files   = array();
   1335 
   1336 		/**
   1337 		 * Filters the array of excluded directories and files while scanning theme folder.
   1338 		 *
   1339 		 * @since 4.7.4
   1340 		 *
   1341 		 * @param string[] $exclusions Array of excluded directories and files.
   1342 		 */
   1343 		$exclusions = (array) apply_filters( 'theme_scandir_exclusions', array( 'CVS', 'node_modules', 'vendor', 'bower_components' ) );
   1344 
   1345 		foreach ( $results as $result ) {
   1346 			if ( '.' === $result[0] || in_array( $result, $exclusions, true ) ) {
   1347 				continue;
   1348 			}
   1349 			if ( is_dir( $path . '/' . $result ) ) {
   1350 				if ( ! $depth ) {
   1351 					continue;
   1352 				}
   1353 				$found = self::scandir( $path . '/' . $result, $extensions, $depth - 1, $relative_path . $result );
   1354 				$files = array_merge_recursive( $files, $found );
   1355 			} elseif ( ! $extensions || preg_match( '~\.(' . $_extensions . ')$~', $result ) ) {
   1356 				$files[ $relative_path . $result ] = $path . '/' . $result;
   1357 			}
   1358 		}
   1359 
   1360 		return $files;
   1361 	}
   1362 
   1363 	/**
   1364 	 * Loads the theme's textdomain.
   1365 	 *
   1366 	 * Translation files are not inherited from the parent theme. TODO: If this fails for the
   1367 	 * child theme, it should probably try to load the parent theme's translations.
   1368 	 *
   1369 	 * @since 3.4.0
   1370 	 *
   1371 	 * @return bool True if the textdomain was successfully loaded or has already been loaded.
   1372 	 *  False if no textdomain was specified in the file headers, or if the domain could not be loaded.
   1373 	 */
   1374 	public function load_textdomain() {
   1375 		if ( isset( $this->textdomain_loaded ) ) {
   1376 			return $this->textdomain_loaded;
   1377 		}
   1378 
   1379 		$textdomain = $this->get( 'TextDomain' );
   1380 		if ( ! $textdomain ) {
   1381 			$this->textdomain_loaded = false;
   1382 			return false;
   1383 		}
   1384 
   1385 		if ( is_textdomain_loaded( $textdomain ) ) {
   1386 			$this->textdomain_loaded = true;
   1387 			return true;
   1388 		}
   1389 
   1390 		$path       = $this->get_stylesheet_directory();
   1391 		$domainpath = $this->get( 'DomainPath' );
   1392 		if ( $domainpath ) {
   1393 			$path .= $domainpath;
   1394 		} else {
   1395 			$path .= '/languages';
   1396 		}
   1397 
   1398 		$this->textdomain_loaded = load_theme_textdomain( $textdomain, $path );
   1399 		return $this->textdomain_loaded;
   1400 	}
   1401 
   1402 	/**
   1403 	 * Whether the theme is allowed (multisite only).
   1404 	 *
   1405 	 * @since 3.4.0
   1406 	 *
   1407 	 * @param string $check   Optional. Whether to check only the 'network'-wide settings, the 'site'
   1408 	 *                        settings, or 'both'. Defaults to 'both'.
   1409 	 * @param int    $blog_id Optional. Ignored if only network-wide settings are checked. Defaults to current site.
   1410 	 * @return bool Whether the theme is allowed for the network. Returns true in single-site.
   1411 	 */
   1412 	public function is_allowed( $check = 'both', $blog_id = null ) {
   1413 		if ( ! is_multisite() ) {
   1414 			return true;
   1415 		}
   1416 
   1417 		if ( 'both' === $check || 'network' === $check ) {
   1418 			$allowed = self::get_allowed_on_network();
   1419 			if ( ! empty( $allowed[ $this->get_stylesheet() ] ) ) {
   1420 				return true;
   1421 			}
   1422 		}
   1423 
   1424 		if ( 'both' === $check || 'site' === $check ) {
   1425 			$allowed = self::get_allowed_on_site( $blog_id );
   1426 			if ( ! empty( $allowed[ $this->get_stylesheet() ] ) ) {
   1427 				return true;
   1428 			}
   1429 		}
   1430 
   1431 		return false;
   1432 	}
   1433 
   1434 	/**
   1435 	 * Determines the latest WordPress default theme that is installed.
   1436 	 *
   1437 	 * This hits the filesystem.
   1438 	 *
   1439 	 * @since 4.4.0
   1440 	 *
   1441 	 * @return WP_Theme|false Object, or false if no theme is installed, which would be bad.
   1442 	 */
   1443 	public static function get_core_default_theme() {
   1444 		foreach ( array_reverse( self::$default_themes ) as $slug => $name ) {
   1445 			$theme = wp_get_theme( $slug );
   1446 			if ( $theme->exists() ) {
   1447 				return $theme;
   1448 			}
   1449 		}
   1450 		return false;
   1451 	}
   1452 
   1453 	/**
   1454 	 * Returns array of stylesheet names of themes allowed on the site or network.
   1455 	 *
   1456 	 * @since 3.4.0
   1457 	 *
   1458 	 * @param int $blog_id Optional. ID of the site. Defaults to the current site.
   1459 	 * @return string[] Array of stylesheet names.
   1460 	 */
   1461 	public static function get_allowed( $blog_id = null ) {
   1462 		/**
   1463 		 * Filters the array of themes allowed on the network.
   1464 		 *
   1465 		 * Site is provided as context so that a list of network allowed themes can
   1466 		 * be filtered further.
   1467 		 *
   1468 		 * @since 4.5.0
   1469 		 *
   1470 		 * @param string[] $allowed_themes An array of theme stylesheet names.
   1471 		 * @param int      $blog_id        ID of the site.
   1472 		 */
   1473 		$network = (array) apply_filters( 'network_allowed_themes', self::get_allowed_on_network(), $blog_id );
   1474 		return $network + self::get_allowed_on_site( $blog_id );
   1475 	}
   1476 
   1477 	/**
   1478 	 * Returns array of stylesheet names of themes allowed on the network.
   1479 	 *
   1480 	 * @since 3.4.0
   1481 	 *
   1482 	 * @return string[] Array of stylesheet names.
   1483 	 */
   1484 	public static function get_allowed_on_network() {
   1485 		static $allowed_themes;
   1486 		if ( ! isset( $allowed_themes ) ) {
   1487 			$allowed_themes = (array) get_site_option( 'allowedthemes' );
   1488 		}
   1489 
   1490 		/**
   1491 		 * Filters the array of themes allowed on the network.
   1492 		 *
   1493 		 * @since MU (3.0.0)
   1494 		 *
   1495 		 * @param string[] $allowed_themes An array of theme stylesheet names.
   1496 		 */
   1497 		$allowed_themes = apply_filters( 'allowed_themes', $allowed_themes );
   1498 
   1499 		return $allowed_themes;
   1500 	}
   1501 
   1502 	/**
   1503 	 * Returns array of stylesheet names of themes allowed on the site.
   1504 	 *
   1505 	 * @since 3.4.0
   1506 	 *
   1507 	 * @param int $blog_id Optional. ID of the site. Defaults to the current site.
   1508 	 * @return string[] Array of stylesheet names.
   1509 	 */
   1510 	public static function get_allowed_on_site( $blog_id = null ) {
   1511 		static $allowed_themes = array();
   1512 
   1513 		if ( ! $blog_id || ! is_multisite() ) {
   1514 			$blog_id = get_current_blog_id();
   1515 		}
   1516 
   1517 		if ( isset( $allowed_themes[ $blog_id ] ) ) {
   1518 			/**
   1519 			 * Filters the array of themes allowed on the site.
   1520 			 *
   1521 			 * @since 4.5.0
   1522 			 *
   1523 			 * @param string[] $allowed_themes An array of theme stylesheet names.
   1524 			 * @param int      $blog_id        ID of the site. Defaults to current site.
   1525 			 */
   1526 			return (array) apply_filters( 'site_allowed_themes', $allowed_themes[ $blog_id ], $blog_id );
   1527 		}
   1528 
   1529 		$current = get_current_blog_id() == $blog_id;
   1530 
   1531 		if ( $current ) {
   1532 			$allowed_themes[ $blog_id ] = get_option( 'allowedthemes' );
   1533 		} else {
   1534 			switch_to_blog( $blog_id );
   1535 			$allowed_themes[ $blog_id ] = get_option( 'allowedthemes' );
   1536 			restore_current_blog();
   1537 		}
   1538 
   1539 		// This is all super old MU back compat joy.
   1540 		// 'allowedthemes' keys things by stylesheet. 'allowed_themes' keyed things by name.
   1541 		if ( false === $allowed_themes[ $blog_id ] ) {
   1542 			if ( $current ) {
   1543 				$allowed_themes[ $blog_id ] = get_option( 'allowed_themes' );
   1544 			} else {
   1545 				switch_to_blog( $blog_id );
   1546 				$allowed_themes[ $blog_id ] = get_option( 'allowed_themes' );
   1547 				restore_current_blog();
   1548 			}
   1549 
   1550 			if ( ! is_array( $allowed_themes[ $blog_id ] ) || empty( $allowed_themes[ $blog_id ] ) ) {
   1551 				$allowed_themes[ $blog_id ] = array();
   1552 			} else {
   1553 				$converted = array();
   1554 				$themes    = wp_get_themes();
   1555 				foreach ( $themes as $stylesheet => $theme_data ) {
   1556 					if ( isset( $allowed_themes[ $blog_id ][ $theme_data->get( 'Name' ) ] ) ) {
   1557 						$converted[ $stylesheet ] = true;
   1558 					}
   1559 				}
   1560 				$allowed_themes[ $blog_id ] = $converted;
   1561 			}
   1562 			// Set the option so we never have to go through this pain again.
   1563 			if ( is_admin() && $allowed_themes[ $blog_id ] ) {
   1564 				if ( $current ) {
   1565 					update_option( 'allowedthemes', $allowed_themes[ $blog_id ] );
   1566 					delete_option( 'allowed_themes' );
   1567 				} else {
   1568 					switch_to_blog( $blog_id );
   1569 					update_option( 'allowedthemes', $allowed_themes[ $blog_id ] );
   1570 					delete_option( 'allowed_themes' );
   1571 					restore_current_blog();
   1572 				}
   1573 			}
   1574 		}
   1575 
   1576 		/** This filter is documented in wp-includes/class-wp-theme.php */
   1577 		return (array) apply_filters( 'site_allowed_themes', $allowed_themes[ $blog_id ], $blog_id );
   1578 	}
   1579 
   1580 	/**
   1581 	 * Enables a theme for all sites on the current network.
   1582 	 *
   1583 	 * @since 4.6.0
   1584 	 *
   1585 	 * @param string|string[] $stylesheets Stylesheet name or array of stylesheet names.
   1586 	 */
   1587 	public static function network_enable_theme( $stylesheets ) {
   1588 		if ( ! is_multisite() ) {
   1589 			return;
   1590 		}
   1591 
   1592 		if ( ! is_array( $stylesheets ) ) {
   1593 			$stylesheets = array( $stylesheets );
   1594 		}
   1595 
   1596 		$allowed_themes = get_site_option( 'allowedthemes' );
   1597 		foreach ( $stylesheets as $stylesheet ) {
   1598 			$allowed_themes[ $stylesheet ] = true;
   1599 		}
   1600 
   1601 		update_site_option( 'allowedthemes', $allowed_themes );
   1602 	}
   1603 
   1604 	/**
   1605 	 * Disables a theme for all sites on the current network.
   1606 	 *
   1607 	 * @since 4.6.0
   1608 	 *
   1609 	 * @param string|string[] $stylesheets Stylesheet name or array of stylesheet names.
   1610 	 */
   1611 	public static function network_disable_theme( $stylesheets ) {
   1612 		if ( ! is_multisite() ) {
   1613 			return;
   1614 		}
   1615 
   1616 		if ( ! is_array( $stylesheets ) ) {
   1617 			$stylesheets = array( $stylesheets );
   1618 		}
   1619 
   1620 		$allowed_themes = get_site_option( 'allowedthemes' );
   1621 		foreach ( $stylesheets as $stylesheet ) {
   1622 			if ( isset( $allowed_themes[ $stylesheet ] ) ) {
   1623 				unset( $allowed_themes[ $stylesheet ] );
   1624 			}
   1625 		}
   1626 
   1627 		update_site_option( 'allowedthemes', $allowed_themes );
   1628 	}
   1629 
   1630 	/**
   1631 	 * Sorts themes by name.
   1632 	 *
   1633 	 * @since 3.4.0
   1634 	 *
   1635 	 * @param WP_Theme[] $themes Array of theme objects to sort (passed by reference).
   1636 	 */
   1637 	public static function sort_by_name( &$themes ) {
   1638 		if ( 0 === strpos( get_user_locale(), 'en_' ) ) {
   1639 			uasort( $themes, array( 'WP_Theme', '_name_sort' ) );
   1640 		} else {
   1641 			foreach ( $themes as $key => $theme ) {
   1642 				$theme->translate_header( 'Name', $theme->headers['Name'] );
   1643 			}
   1644 			uasort( $themes, array( 'WP_Theme', '_name_sort_i18n' ) );
   1645 		}
   1646 	}
   1647 
   1648 	/**
   1649 	 * Callback function for usort() to naturally sort themes by name.
   1650 	 *
   1651 	 * Accesses the Name header directly from the class for maximum speed.
   1652 	 * Would choke on HTML but we don't care enough to slow it down with strip_tags().
   1653 	 *
   1654 	 * @since 3.4.0
   1655 	 *
   1656 	 * @param WP_Theme $a First theme.
   1657 	 * @param WP_Theme $b Second theme.
   1658 	 * @return int Negative if `$a` falls lower in the natural order than `$b`. Zero if they fall equally.
   1659 	 *             Greater than 0 if `$a` falls higher in the natural order than `$b`. Used with usort().
   1660 	 */
   1661 	private static function _name_sort( $a, $b ) {
   1662 		return strnatcasecmp( $a->headers['Name'], $b->headers['Name'] );
   1663 	}
   1664 
   1665 	/**
   1666 	 * Callback function for usort() to naturally sort themes by translated name.
   1667 	 *
   1668 	 * @since 3.4.0
   1669 	 *
   1670 	 * @param WP_Theme $a First theme.
   1671 	 * @param WP_Theme $b Second theme.
   1672 	 * @return int Negative if `$a` falls lower in the natural order than `$b`. Zero if they fall equally.
   1673 	 *             Greater than 0 if `$a` falls higher in the natural order than `$b`. Used with usort().
   1674 	 */
   1675 	private static function _name_sort_i18n( $a, $b ) {
   1676 		return strnatcasecmp( $a->name_translated, $b->name_translated );
   1677 	}
   1678 }