Media: Default to always showing the "Create Audio/Video Playlist" bu…

…ttons.

This avoids a couple of expensive queries that attempt to determine whether the media library contains any audio or video items, and also makes the UI for creating playlists more discoverable.

[40382] and [40421] added filters to allow overriding this behavior; this commit changes the default value of the filters to always show these UI buttons and never run the expensive queries.  The old behavior can still be restored using the filters if desired.

Props sboisvert, adamsilverstein, joemcgill, jnylen0.
Fixes #31071.

Built from https://develop.svn.wordpress.org/trunk@40430


git-svn-id: http://core.svn.wordpress.org/trunk@40328 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/media.php

@@ -3324,18 +3324,21 @@ function wp_enqueue_media( $args = array() ) {
 	/**
 	 * Allows showing or hiding the "Create Audio Playlist" button in the media library.
 	 *
-	 * By default (if this filter returns `null`), a query will be run to
-	 * determine whether the media library contains any audio items.  This
-	 * query is expensive for large media libraries, so it may be desirable for
-	 * sites to override this behavior.
+	 * By default, the "Create Audio Playlist" button will always be shown in
+	 * the media library.  If this filter returns `null`, a query will be run
+	 * to determine whether the media library contains any audio items.  This
+	 * was the default behavior prior to version 4.8.0, but this query is
+	 * expensive for large media libraries.
 	 *
 	 * @since 4.7.4
+	 * @since 4.8.0 The filter's default value is `true` rather than `null`.
 	 *
 	 * @link https://core.trac.wordpress.org/ticket/31071
 	 *
-	 * @param bool|null Whether to show the button, or `null` for default behavior.
+	 * @param bool|null Whether to show the button, or `null` to decide based
+	 *                  on whether any audio files exist in the media library.
 	 */
-	$show_audio_playlist = apply_filters( 'media_library_show_audio_playlist', null );
+	$show_audio_playlist = apply_filters( 'media_library_show_audio_playlist', true );
 	if ( null === $show_audio_playlist ) {
 		$show_audio_playlist = $wpdb->get_var( "
 			SELECT ID
@@ -3349,18 +3352,21 @@ function wp_enqueue_media( $args = array() ) {
 	/**
 	 * Allows showing or hiding the "Create Video Playlist" button in the media library.
 	 *
-	 * By default (if this filter returns `null`), a query will be run to
-	 * determine whether the media library contains any video items.  This
-	 * query is expensive for large media libraries, so it may be desirable for
-	 * sites to override this behavior.
+	 * By default, the "Create Video Playlist" button will always be shown in
+	 * the media library.  If this filter returns `null`, a query will be run
+	 * to determine whether the media library contains any video items.  This
+	 * was the default behavior prior to version 4.8.0, but this query is
+	 * expensive for large media libraries.
 	 *
 	 * @since 4.7.4
+	 * @since 4.8.0 The filter's default value is `true` rather than `null`.
 	 *
 	 * @link https://core.trac.wordpress.org/ticket/31071
 	 *
-	 * @param bool|null Whether to show the button, or `null` for default behavior.
+	 * @param bool|null Whether to show the button, or `null` to decide based
+	 *                  on whether any video files exist in the media library.
 	 */
-	$show_video_playlist = apply_filters( 'media_library_show_video_playlist', null );
+	$show_video_playlist = apply_filters( 'media_library_show_video_playlist', true );
 	if ( null === $show_video_playlist ) {
 		$show_video_playlist = $wpdb->get_var( "
 			SELECT ID

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-40428';
+$wp_version = '4.8-alpha-40430';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.