bug: set order of mimetypes to avif 1st, webp2. reuse protected class variable for checking if source an optimized image

Author: tijmenbruggeman

src/class-tiny-picture.php

@@ -198,7 +198,7 @@ public function __construct( $html, $base_dir, $domains ) {
 		$this->raw_html 	   = $html;
 		$this->base_dir        = $base_dir;
 		$this->allowed_domains = $domains;
-		$this->valid_mimetypes = array( 'image/webp', 'image/avif' );
+		$this->valid_mimetypes = array(  'image/avif', 'image/webp' );
 	}
 
 	protected static function get_attribute_value( $element, $name ) {
@@ -405,15 +405,12 @@ class Tiny_Picture_Source extends Tiny_Source_Base {
 	public function augment_picture_element() {
 		$modified_sources = array();
 
-		// handle existing sources
-		$optimized_types = [ 'image/webp', 'image/avif' ];
-
 		foreach ( $this->get_element_by_tag( $this->raw_html, 'source' ) as $source_tag_html ) {
 			$type_attr = self::get_attribute_value( $source_tag_html, 'type' );
 			$type_attr = null !== $type_attr ? strtolower( trim( $type_attr ) ) : '';
 
 			// Skip if already optimized.
-			if ( '' !== $type_attr && in_array( $type_attr, $optimized_types, true ) ) {
+			if ( '' !== $type_attr && in_array( $type_attr, $this->valid_mimetypes, true ) ) {
 				continue;
 			}
 

test/unit/TinyPictureTest.php

@@ -199,7 +199,7 @@ public function test_adds_both_avif_and_webp()
         $this->wp->createImage(1000, '2025/01', 'test.avif');
 
         $input = '<img src="/wp-content/uploads/2025/01/test.png">';
-        $expected = '<picture><source srcset="/wp-content/uploads/2025/01/test.webp" type="image/webp" /><source srcset="/wp-content/uploads/2025/01/test.avif" type="image/avif" /><img src="/wp-content/uploads/2025/01/test.png"></picture>';
+        $expected = '<picture><source srcset="/wp-content/uploads/2025/01/test.avif" type="image/avif" /><source srcset="/wp-content/uploads/2025/01/test.webp" type="image/webp" /><img src="/wp-content/uploads/2025/01/test.png"></picture>';
         $output = $this->tiny_picture->replace_sources($input);
 
         $this->assertEquals($expected, $output);