Lazy Images: Add filter to allow skipping an image with certain attri…

…butes
Automattic · Feb 8, 2018 · 3a7eaa3 · 3a7eaa3
1 parent ed23c90
commit 3a7eaa3
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Showing 2 changed files with 34 additions and 0 deletions.
diff --git a/modules/lazy-images/lazy-images.php b/modules/lazy-images/lazy-images.php
@@ -176,6 +176,20 @@ static function process_image( $matches ) {
 			return $matches[0];
 		}
 
+		/**
+		 * Allow plugins and themes to conditionally skip processing an image via its attributes.
+		 *
+		 * @module-lazy-images
+		 *
+		 * @since 5.9.0
+		 *
+		 * @param bool  Default to not skip processing the current image.
+		 * @param array An array of attributes via wp_kses_hair() for the current image.
+		 */
+		if ( apply_filters( 'jetpack_lazy_images_skip_image_with_atttributes', false, $old_attributes_kses_hair ) ) {
+			return $matches[0];
+		}
+
 		$old_attributes = self::flatten_kses_hair_data( $old_attributes_kses_hair );
 		$new_attributes = self::process_image_attributes( $old_attributes );
 		$new_attributes_str = self::build_attributes_string( $new_attributes );

diff --git a/tests/php/modules/lazy-images/test_class.lazy-images.php b/tests/php/modules/lazy-images/test_class.lazy-images.php
@@ -278,6 +278,22 @@ function get_should_skip_image_with_filtered_empty_blacklist_data() {
 		);
 	}
 
+	function test_jetpack_lazy_images_skip_image_with_atttributes_filter() {
+		$instance = Jetpack_Lazy_Images::instance();
+		$src = '<img src="image.jpg" srcset="medium.jpg 1000w, large.jpg 2000w" class="wp-post-image"/>';
+
+		$this->assertContains( 'src="placeholder.jpg"', $instance->add_image_placeholders( $src ) );
+
+		add_filter( 'jetpack_lazy_images_skip_image_with_atttributes', '__return_true' );
+		$this->assertNotContains( 'src="placeholder.jpg"', $instance->add_image_placeholders( $src ) );
+		remove_filter( 'jetpack_lazy_images_skip_image_with_atttributes', '__return_true' );
+
+		add_filter( 'jetpack_lazy_images_skip_image_with_atttributes', array( $this, '__skip_if_srcset' ), 10, 2 );
+		$this->assertNotContains( 'src="placeholder.jpg"', $instance->add_image_placeholders( $src ) );
+		$this->assertContains( 'src="placeholder.jpg"', $instance->add_image_placeholders( '<img src="image.jpg" />' ) );
+		remove_filter( 'jetpack_lazy_images_skip_image_with_atttributes', array( $this, '__skip_if_srcset' ), 10, 2 );
+	}
+
 	/*
 	 * Helpers
 	 */
@@ -314,4 +330,8 @@ public function __get_output_content() {
 
 		return trim( $contents );
 	}
+
+	public function __skip_if_srcset( $should_skip, $attributes ) {
+		return isset( $attributes['srcset'] );
+	}
 }