X-Git-Url: https://scripts.mit.edu/gitweb/autoinstalls/wordpress.git/blobdiff_plain/f9001779751f83dc8a10e478bfecb4d8dd5f964c..8d3bb1a5dcfdea9857d3c88c3751f09593e34dc8:/wp-includes/post-thumbnail-template.php

diff --git a/wp-includes/post-thumbnail-template.php b/wp-includes/post-thumbnail-template.php
index 3758d1d4..4722565d 100644
--- a/wp-includes/post-thumbnail-template.php
+++ b/wp-includes/post-thumbnail-template.php
@@ -2,8 +2,8 @@
 /**
  * WordPress Post Thumbnail Template Functions.
  *
- * Support for post thumbnails
- * Themes function.php must call add_theme_support( 'post-thumbnails' ) to use these.
+ * Support for post thumbnails.
+ * Theme's functions.php must call add_theme_support( 'post-thumbnails' ) to use these.
  *
  * @package WordPress
  * @subpackage Template
@@ -13,61 +13,241 @@
  * Check if post has an image attached.
  *
  * @since 2.9.0
+ * @since 4.4.0 `$post` can be a post ID or WP_Post object.
  *
- * @param int $post_id Optional. Post ID.
- * @return bool Whether post has an image attached.
+ * @param int|WP_Post $post Optional. Post ID or WP_Post object. Default is global `$post`.
+ * @return bool Whether the post has an image attached.
  */
-function has_post_thumbnail( $post_id = null ) {
-	$post_id = ( null === $post_id ) ? get_the_ID() : $post_id;
-	return (bool) get_post_thumbnail_id( $post_id );
+function has_post_thumbnail( $post = null ) {
+	return (bool) get_post_thumbnail_id( $post );
 }
 
 /**
- * Retrieve Post Thumbnail ID.
+ * Retrieve post thumbnail ID.
  *
  * @since 2.9.0
+ * @since 4.4.0 `$post` can be a post ID or WP_Post object.
  *
- * @param int $post_id Optional. Post ID.
- * @return int
+ * @param int|WP_Post $post Optional. Post ID or WP_Post object. Default is global `$post`.
+ * @return string|int Post thumbnail ID or empty string.
  */
-function get_post_thumbnail_id( $post_id = null ) {
-	$post_id = ( null === $post_id ) ? get_the_ID() : $post_id;
-	return get_post_meta( $post_id, '_thumbnail_id', true );
+function get_post_thumbnail_id( $post = null ) {
+	$post = get_post( $post );
+	if ( ! $post ) {
+		return '';
+	}
+	return get_post_meta( $post->ID, '_thumbnail_id', true );
 }
 
 /**
- * Display Post Thumbnail.
+ * Display the post thumbnail.
+ *
+ * When a theme adds 'post-thumbnail' support, a special 'post-thumbnail' image size
+ * is registered, which differs from the 'thumbnail' image size managed via the
+ * Settings > Media screen.
+ *
+ * When using the_post_thumbnail() or related functions, the 'post-thumbnail' image
+ * size is used by default, though a different size can be specified instead as needed.
  *
  * @since 2.9.0
  *
- * @param int $size Optional. Image size.  Defaults to 'post-thumbnail', which theme sets using set_post_thumbnail_size( $width, $height, $crop_flag );.
- * @param string|array $attr Optional. Query string or array of attributes.
+ * @see get_the_post_thumbnail()
+ *
+ * @param string|array $size Optional. Image size to use. Accepts any valid image size, or
+ *                           an array of width and height values in pixels (in that order).
+ *                           Default 'post-thumbnail'.
+ * @param string|array $attr Optional. Query string or array of attributes. Default empty.
  */
 function the_post_thumbnail( $size = 'post-thumbnail', $attr = '' ) {
 	echo get_the_post_thumbnail( null, $size, $attr );
 }
 
 /**
- * Retrieve Post Thumbnail.
+ * Update cache for thumbnails in the current loop.
+ *
+ * @since 3.2.0
+ *
+ * @global WP_Query $wp_query
+ *
+ * @param WP_Query $wp_query Optional. A WP_Query instance. Defaults to the $wp_query global.
+ */
+function update_post_thumbnail_cache( $wp_query = null ) {
+	if ( ! $wp_query )
+		$wp_query = $GLOBALS['wp_query'];
+
+	if ( $wp_query->thumbnails_cached )
+		return;
+
+	$thumb_ids = array();
+	foreach ( $wp_query->posts as $post ) {
+		if ( $id = get_post_thumbnail_id( $post->ID ) )
+			$thumb_ids[] = $id;
+	}
+
+	if ( ! empty ( $thumb_ids ) ) {
+		_prime_post_caches( $thumb_ids, false, true );
+	}
+
+	$wp_query->thumbnails_cached = true;
+}
+
+/**
+ * Retrieve the post thumbnail.
+ *
+ * When a theme adds 'post-thumbnail' support, a special 'post-thumbnail' image size
+ * is registered, which differs from the 'thumbnail' image size managed via the
+ * Settings > Media screen.
+ *
+ * When using the_post_thumbnail() or related functions, the 'post-thumbnail' image
+ * size is used by default, though a different size can be specified instead as needed.
  *
  * @since 2.9.0
+ * @since 4.4.0 `$post` can be a post ID or WP_Post object.
  *
- * @param int $post_id Optional. Post ID.
- * @param string $size Optional. Image size.  Defaults to 'thumbnail'.
- * @param string|array $attr Optional. Query string or array of attributes.
+ * @param int|WP_Post  $post Optional. Post ID or WP_Post object.  Default is global `$post`.
+ * @param string|array $size Optional. Image size to use. Accepts any valid image size, or
+ *                           an array of width and height values in pixels (in that order).
+ *                           Default 'post-thumbnail'.
+ * @param string|array $attr Optional. Query string or array of attributes. Default empty.
+ * @return string The post thumbnail image tag.
  */
-function get_the_post_thumbnail( $post_id = null, $size = 'post-thumbnail', $attr = '' ) {
-	$post_id = ( null === $post_id ) ? get_the_ID() : $post_id;
-	$post_thumbnail_id = get_post_thumbnail_id( $post_id );
+function get_the_post_thumbnail( $post = null, $size = 'post-thumbnail', $attr = '' ) {
+	$post = get_post( $post );
+	if ( ! $post ) {
+		return '';
+	}
+	$post_thumbnail_id = get_post_thumbnail_id( $post );
+
+	/**
+	 * Filters the post thumbnail size.
+	 *
+	 * @since 2.9.0
+	 *
+	 * @param string|array $size The post thumbnail size. Image size or array of width and height
+	 *                           values (in that order). Default 'post-thumbnail'.
+	 */
 	$size = apply_filters( 'post_thumbnail_size', $size );
+
 	if ( $post_thumbnail_id ) {
-		do_action( 'begin_fetch_post_thumbnail_html', $post_id, $post_thumbnail_id, $size ); // for "Just In Time" filtering of all of wp_get_attachment_image()'s filters
+
+		/**
+		 * Fires before fetching the post thumbnail HTML.
+		 *
+		 * Provides "just in time" filtering of all filters in wp_get_attachment_image().
+		 *
+		 * @since 2.9.0
+		 *
+		 * @param int          $post_id           The post ID.
+		 * @param string       $post_thumbnail_id The post thumbnail ID.
+		 * @param string|array $size              The post thumbnail size. Image size or array of width
+		 *                                        and height values (in that order). Default 'post-thumbnail'.
+		 */
+		do_action( 'begin_fetch_post_thumbnail_html', $post->ID, $post_thumbnail_id, $size );
+		if ( in_the_loop() )
+			update_post_thumbnail_cache();
 		$html = wp_get_attachment_image( $post_thumbnail_id, $size, false, $attr );
-		do_action( 'end_fetch_post_thumbnail_html', $post_id, $post_thumbnail_id, $size );
+
+		/**
+		 * Fires after fetching the post thumbnail HTML.
+		 *
+		 * @since 2.9.0
+		 *
+		 * @param int          $post_id           The post ID.
+		 * @param string       $post_thumbnail_id The post thumbnail ID.
+		 * @param string|array $size              The post thumbnail size. Image size or array of width
+		 *                                        and height values (in that order). Default 'post-thumbnail'.
+		 */
+		do_action( 'end_fetch_post_thumbnail_html', $post->ID, $post_thumbnail_id, $size );
+
 	} else {
 		$html = '';
 	}
-	return apply_filters( 'post_thumbnail_html', $html, $post_id, $post_thumbnail_id, $size, $attr );
+	/**
+	 * Filters the post thumbnail HTML.
+	 *
+	 * @since 2.9.0
+	 *
+	 * @param string       $html              The post thumbnail HTML.
+	 * @param int          $post_id           The post ID.
+	 * @param string       $post_thumbnail_id The post thumbnail ID.
+	 * @param string|array $size              The post thumbnail size. Image size or array of width and height
+	 *                                        values (in that order). Default 'post-thumbnail'.
+	 * @param string       $attr              Query string of attributes.
+	 */
+	return apply_filters( 'post_thumbnail_html', $html, $post->ID, $post_thumbnail_id, $size, $attr );
 }
 
-?>
+/**
+ * Return the post thumbnail URL.
+ *
+ * @since 4.4.0
+ *
+ * @param int|WP_Post  $post Optional. Post ID or WP_Post object.  Default is global `$post`.
+ * @param string|array $size Optional. Registered image size to retrieve the source for or a flat
+ *                           array of height and width dimensions. Default 'post-thumbnail'.
+ * @return string|false Post thumbnail URL or false if no URL is available.
+ */
+function get_the_post_thumbnail_url( $post = null, $size = 'post-thumbnail' ) {
+	$post_thumbnail_id = get_post_thumbnail_id( $post );
+	if ( ! $post_thumbnail_id ) {
+		return false;
+	}
+	return wp_get_attachment_image_url( $post_thumbnail_id, $size );
+}
+
+/**
+ * Display the post thumbnail URL.
+ *
+ * @since 4.4.0
+ *
+ * @param string|array $size Optional. Image size to use. Accepts any valid image size,
+ *                           or an array of width and height values in pixels (in that order).
+ *                           Default 'post-thumbnail'.
+ */
+function the_post_thumbnail_url( $size = 'post-thumbnail' ) {
+	$url = get_the_post_thumbnail_url( null, $size );
+	if ( $url ) {
+		echo esc_url( $url );
+	}
+}
+
+/**
+ * Returns the post thumbnail caption.
+ *
+ * @since 4.6.0
+ *
+ * @param int|WP_Post $post Optional. Post ID or WP_Post object. Default is global `$post`.
+ * @return string Post thumbnail caption.
+ */
+function get_the_post_thumbnail_caption( $post = null ) {
+	$post_thumbnail_id = get_post_thumbnail_id( $post );
+	if ( ! $post_thumbnail_id ) {
+		return '';
+	}
+
+	$caption = wp_get_attachment_caption( $post_thumbnail_id );
+
+	if ( ! $caption ) {
+		$caption = '';
+	}
+
+	return $caption;
+}
+
+/**
+ * Displays the post thumbnail caption.
+ *
+ * @since 4.6.0
+ *
+ * @param int|WP_Post $post Optional. Post ID or WP_Post object. Default is global `$post`.
+ */
+function the_post_thumbnail_caption( $post = null ) {
+	/**
+	 * Filters the displayed post thumbnail caption.
+	 *
+	 * @since 4.6.0
+	 *
+	 * @param string $caption Caption for the given attachment.
+	 */
+	echo apply_filters( 'the_post_thumbnail_caption', get_the_post_thumbnail_caption( $post ) );
+}