Ticket #42350: 42350.2.diff

src/wp-includes/widgets/class-wp-widget-media-image.php

@@ -177 +177 @@
                         $attachment = get_post( $instance['attachment_id'] );
                 }
                 if ( $attachment ) {
-                        $caption = $attachment->post_excerpt;
-                        if ( $instance['caption'] ) {
+                        $caption = '';
+                        if ( trim( $instance['caption'] ) ) {
                                 $caption = $instance['caption'];
+                        } elseif ( null === $instance['caption'] ) {
+                                $caption = $attachment->post_excerpt;
                         }
 
                         $image_attributes = array(

tests/phpunit/tests/widgets/media-image-widget.php

@@ -425 +425 @@
                 $this->assertContains( '<a href="https://example.org"', $output );
                 $this->assertContains( 'target="_blank"', $output );
 
-                // Caption settings.
+                // Populate caption in attachment.
                 wp_update_post( array(
                         'ID' => $attachment_id,
                         'post_excerpt' => 'Default caption',
                 ) );
 
+                // If no caption is supplied, then the default is '', and so the caption will not be displayed.
                 ob_start();
                 $widget->render_media( array(
                         'attachment_id' => $attachment_id,
                 ) );
                 $output = ob_get_clean();
+                $this->assertNotContains( 'wp-caption', $output );
+                $this->assertNotContains( '<p class="wp-caption-text">', $output );
 
+                // If the caption is explicitly null, then the caption of the underlying attachment will be displayed.
+                ob_start();
+                $widget->render_media( array(
+                        'attachment_id' => $attachment_id,
+                        'caption' => null,
+                ) );
+                $output = ob_get_clean();
                 $this->assertContains( 'class="wp-caption alignnone"', $output );
                 $this->assertContains( '<p class="wp-caption-text">Default caption</p>', $output );
 
+                // If caption is provided, then it will be displayed.
                 ob_start();
                 $widget->render_media( array(
                         'attachment_id' => $attachment_id,
                         'caption' => 'Custom caption',
                 ) );
                 $output = ob_get_clean();
-
                 $this->assertContains( 'class="wp-caption alignnone"', $output );
                 $this->assertContains( '<p class="wp-caption-text">Custom caption</p>', $output );
         }