Ticket #52867: 52867.7.diff

src/wp-includes/class-wp-image-editor.php

@@ -316 +316 @@
                         $new_ext   = $file_ext;
                 }
 
+                /**
+                 * Filters the image editor output format mapping.
+                 *
+                 * Enables filtering the mime type used to save images. By default,
+                 * the mapping array is empty, so the mime type matches the source image.
+                 *
+                 * @see src/wp-includes/class-wp-image-editor.php -> get_output_format()
+                 *
+                 * @since 5.8.0
+                 *
+                 * @param array $wp_image_editor_output_format {
+                 *     An array of mime type mappings. Maps a source mime type to a new
+                 *     destination mime type. Empty by default.
+                 *
+                 *     @type array $mime_type The source mime type {
+                 *         @type string $mime_type The new mime type.
+                 *     }
+                 * @param string $filename Path to the image.
+                 * @param string $mime_type The source image mime type.
+                 * }
+                 */
+                $wp_image_editor_output_format = apply_filters( 'image_editor_output_format', array(), $filename, $mime_type );
+
+                if (
+                        isset( $wp_image_editor_output_format[ $mime_type ] ) &&
+                        $this->supports_mime_type( $wp_image_editor_output_format[ $mime_type ] )
+                ) {
+                        $mime_type = $wp_image_editor_output_format[ $mime_type ];
+                        $new_ext = $this->get_extension( $mime_type );
+                }
+
                 // Double-check that the mime-type selected is supported by the editor.
                 // If not, choose a default instead.
                 if ( ! $this->supports_mime_type( $mime_type ) ) {

tests/phpunit/tests/image/intermediateSize.php

@@ -62 +62 @@
                 unlink( DIR_TESTDATA . '/images/a2-small-100x75.jpg' );
         }
 
+        /**
+         * @requires function imagejpeg
+         * @ticket 52867
+         */
+        function test_image_editor_output_format_filter() {
+                add_filter(
+                        'image_editor_output_format',
+                        function() {
+                                return array( 'image/jpeg' => 'image/webp' );
+                        }
+                );
+                $file   = DIR_TESTDATA . '/images/waffles.jpg';
+                $image  = image_make_intermediate_size( $file, 100, 75, true );
+                $editor = wp_get_image_editor( $file );
+                if ( is_wp_error( $editor ) || ! $editor->supports_mime_type( 'image/webp' ) ) {
+                        $this->assertSame( 'image/jpeg', $image['mime-type'] );
+                } else {
+                        $this->assertSame( 'image/webp', $image['mime-type'] );
+                }
+                unlink( DIR_TESTDATA . '/images/' . $image['file'] );
+                remove_all_filters( 'image_editor_output_format' );
+        }
+
         /**
          * @ticket 17626
          * @requires function imagejpeg