Changeset 37915

Timestamp:

06/29/2016 05:28:00 PM (8 years ago)

Author:

joemcgill

Message:

Post Thumbnails: Add helper functions for attachment captions.

This adds three new functions for getting/displaying attachment captions:

• wp_get_attachment_caption - Retrieves a caption for a specific attachment.
• get_the_post_thumbnail_caption() - Returns the post thumbnail caption.
• the_post_thumbnail_caption() - Displays the post thumbnail caption.

These are helpful for displaying a caption associated with an image directly
in a template, rather than using the caption shortcode.

This also introduces two new filters:

• wp_get_attachment_caption - Filters the value of wp_get_attachment_caption().
• the_post_thumbnail_caption - Filters the display of the post thumbnail caption.

the_post_thumbnail_caption() is automatically filtered by wptexturize(),
convert_smilies(), and convert_chars() in wp-includes/default-filters.php.

Props flixos90, joemcgill.
Fixes #12235.

Location:

trunk

Files:

• src/wp-includes/default-filters.php (modified) (1 diff)
• src/wp-includes/post-thumbnail-template.php (modified) (1 diff)
• src/wp-includes/post.php (modified) (1 diff)
• tests/phpunit/tests/media.php (modified) (1 diff)
• tests/phpunit/tests/post/thumbnails.php (modified) (1 diff)

trunk/src/wp-includes/default-filters.php

@@ -143 +143 @@
 add_filter( 'the_excerpt',     'shortcode_unautop');
 add_filter( 'get_the_excerpt', 'wp_trim_excerpt'  );
+
+add_filter( 'the_post_thumbnail_caption', 'wptexturize'     );
+add_filter( 'the_post_thumbnail_caption', 'convert_smilies' );
+add_filter( 'the_post_thumbnail_caption', 'convert_chars'   );
 
 add_filter( 'comment_text', 'wptexturize'            );

trunk/src/wp-includes/post-thumbnail-template.php

@@ -211 +211 @@
     }
 }
+
+/**
+ * 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 ) );
+}

trunk/src/wp-includes/post.php

@@ -4938 +4938 @@
 
 /**
+ * Retrieves the caption for an attachment.
+ *
+ * @since 4.6.0
+ *
+ * @param int $post_id Optional. Attachment ID. Default 0.
+ * @return string|false False on failure. Attachment caption on success.
+ */
+function wp_get_attachment_caption( $post_id = 0 ) {
+    $post_id = (int) $post_id;
+    if ( ! $post = get_post( $post_id ) ) {
+        return false;
+    }
+
+    if ( 'attachment' !== $post->post_type ) {
+        return false;
+    }
+
+    $caption = $post->post_excerpt;
+
+    /**
+     * Filters the attachment caption.
+     *
+     * @since 4.6.0
+     *
+     * @param string $caption Caption for the given attachment.
+     * @param int    $post_id Attachment ID.
+     */
+    return apply_filters( 'wp_get_attachment_caption', $caption, $post->ID );
+}
+
+/**
  * Retrieve thumbnail for an attachment.
  *

trunk/tests/phpunit/tests/media.php

@@ -903 +903 @@
 
     /**
+     * @ticket 12235
+     */
+    function test_wp_get_attachment_caption() {
+        $this->assertFalse( wp_get_attachment_caption( 0 ) );
+
+        $caption = 'This is a caption.';
+
+        $post_id = self::factory()->post->create();
+        $attachment_id = self::factory()->attachment->create_object( $this->img_name, $post_id, array(
+            'post_mime_type' => 'image/jpeg',
+            'post_type'      => 'attachment',
+            'post_excerpt'   => $caption,
+        ) );
+
+        $this->assertFalse( wp_get_attachment_caption( $post_id ) );
+
+        $this->assertEquals( $caption, wp_get_attachment_caption( $attachment_id ) );
+    }
+
+    /**
+     * @ticket 12235
+     */
+    function test_wp_get_attachment_caption_empty() {
+        $post_id = self::factory()->post->create();
+        $attachment_id = self::factory()->attachment->create_object( $this->img_name, $post_id, array(
+            'post_mime_type' => 'image/jpeg',
+            'post_type'      => 'attachment',
+            'post_excerpt'   => '',
+        ) );
+
+        $this->assertEquals( '', wp_get_attachment_caption( $attachment_id ) );
+    }
+
+    /**
      * Helper function to get image size array from size "name"
      */

trunk/tests/phpunit/tests/post/thumbnails.php

@@ -75 +75 @@
     }
 
+    /**
+     * @ticket 12235
+     */
+    function test_get_the_post_thumbnail_caption() {
+        $this->assertEquals( '', get_the_post_thumbnail_caption() );
+
+        $caption = 'This is a caption.';
+
+        $post_id = self::factory()->post->create();
+        $attachment_id = self::factory()->attachment->create_object( 'image.jpg', $post_id, array(
+            'post_mime_type' => 'image/jpeg',
+            'post_type'      => 'attachment',
+            'post_excerpt'   => $caption,
+        ) );
+
+        set_post_thumbnail( $post_id, $attachment_id );
+
+        $this->assertEquals( $caption, get_the_post_thumbnail_caption( $post_id ) );
+    }
+
+    /**
+     * @ticket 12235
+     */
+    function test_get_the_post_thumbnail_caption_empty() {
+        $post_id = self::factory()->post->create();
+        $attachment_id = self::factory()->attachment->create_object( 'image.jpg', $post_id, array(
+            'post_mime_type' => 'image/jpeg',
+            'post_type'      => 'attachment',
+            'post_excerpt'   => '',
+        ) );
+
+        set_post_thumbnail( $post_id, $attachment_id );
+
+        $this->assertEquals( '', get_the_post_thumbnail_caption( $post_id ) );
+    }
+
+    /**
+     * @ticket 12235
+     */
+    function test_the_post_thumbnail_caption() {
+        $caption = 'This is a caption.';
+
+        $post_id = self::factory()->post->create();
+        $attachment_id = self::factory()->attachment->create_object( 'image.jpg', $post_id, array(
+            'post_mime_type' => 'image/jpeg',
+            'post_type'      => 'attachment',
+            'post_excerpt'   => $caption,
+        ) );
+
+        set_post_thumbnail( $post_id, $attachment_id );
+
+        ob_start();
+        the_post_thumbnail_caption( $post_id );
+
+        $this->assertEquals( $caption, ob_get_clean() );
+    }
+
     function test_get_the_post_thumbnail() {
         $this->assertEquals( '', get_the_post_thumbnail() );