fix: add logic for sending convert_to params

Author: tijmenbruggeman

src/class-tiny-image.php

@@ -21,6 +21,7 @@
 class Tiny_Image {
 	const ORIGINAL = 0;
 
+	/** @var Tiny_Settings */
 	private $settings;
 	private $id;
 	private $name;
@@ -179,7 +180,6 @@ public function compress() {
 		$success = 0;
 		$failed = 0;
 
-		$compressor = $this->settings->get_compressor();
 		$active_tinify_sizes = $this->settings->get_active_tinify_sizes();
 
 		if ( $this->settings->get_conversion_enabled() ) {
@@ -191,20 +191,26 @@ public function compress() {
 			$unprocessed_sizes = $this->filter_image_sizes( 'uncompressed', $active_tinify_sizes );
 		}
 
+		$compressor = $this->settings->get_compressor();
+		$convert_to = $this->convert_to();
+		
 		foreach ( $unprocessed_sizes as $size_name => $size ) {
 			if ( ! $size->is_duplicate() ) {
 				$size->add_tiny_meta_start();
 				$this->update_tiny_post_meta();
 				$resize = $this->settings->get_resize_options( $size_name );
 				$preserve = $this->settings->get_preserve_options( $size_name );
-				$convert_opts = $this->settings->get_conversion_options();
 				try {
 					$response = $compressor->compress_file(
 						$size->filename,
 						$resize,
 						$preserve,
-						$convert_opts
+						$convert_to
 					);
+
+					// ensure that all conversion are in the same format as the first one
+					$convert_to = isset($response['convert']) ? array($response['convert']['type']) : $convert_to;
+
 					$size->add_tiny_meta( $response );
 					$success++;
 				} catch ( Tiny_Exception $e ) {
@@ -243,17 +249,19 @@ public function compress_retina( $size_name, $path ) {
 		if ( ! isset( $this->sizes[ $size_name ] ) ) {
 			$this->sizes[ $size_name ] = new Tiny_Image_Size( $path );
 		}
+
 		$size = $this->sizes[ $size_name ];
+		
+		$compressor = $this->settings->get_compressor();
+		$convert_to = $this->convert_to();
 
 		if ( ! $size->has_been_compressed() ) {
 			$size->add_tiny_meta_start();
 			$this->update_tiny_post_meta();
-			$compressor = $this->settings->get_compressor();
 			$preserve = $this->settings->get_preserve_options( $size_name );
-			$conversion = $this->settings->get_conversion_options();
 
 			try {
-				$response = $compressor->compress_file( $path, false, $preserve, $conversion );
+				$response = $compressor->compress_file( $path, false, $preserve, $convert_to );
 				$size->add_tiny_meta( $response );
 			} catch ( Tiny_Exception $e ) {
 				$size->add_tiny_meta_error( $e );
@@ -472,6 +480,37 @@ public function can_be_converted() {
 		return $this->settings->get_conversion_enabled() && $this->file_type_allowed();
 	}
 
+	/**
+	 * Get the targeted conversion.
+	 * If original is already converted, then we use the originals' mimetype.
+	 * If nothing is converted yet, we use the settings conversion settings.
+	 *
+	 * @since 3.6.4
+	 * 
+	 * @return array{string} mimetypes to which the image should be converted to
+	 */
+	private function convert_to() {
+		$convert_settings = $this->settings->get_conversion_options();
+		if ( ! $convert_settings['convert'] ) {
+			// conversion is off so return no mimetypes to convert to
+			return array();
+		}
+
+		if ( isset( $this->sizes[ self::ORIGINAL ] ) ) {
+			// original is not in sizes so mimetypes are open
+			return $convert_settings['convert_to'];
+		}
+
+		$original_img_size = $this->sizes[ self::ORIGINAL ];
+		if ( $original_img_size->converted() ) {
+			// original has been convert so use that mimetype to convert to
+			return array($original_img_size->meta['convert']['type']);
+		}
+
+		return $convert_settings['convert_to'];
+		
+	}
+
 	/**
 	 * Marks the image as compressed without actually compressing it.
 	 *

test/unit/TinyImageTest.php

@@ -176,7 +176,7 @@ public function test_update_tiny_post_data_should_call_do_action() {
 	 * In case a customer has already compressed a couple of images and then turns
 	 * on the conversion feature.
 	 */
-public function test_compressed_images_can_be_converted() {
+	public function test_compressed_images_can_be_converted() {
 		// Enable conversion and all image sizes
 		$this->wp->addOption('tinypng_conversion_enabled', true);
 		$this->wp->addOption('tinypng_convert_to', 'smallest');
@@ -194,4 +194,70 @@ public function test_compressed_images_can_be_converted() {
 		$this->assertCount(4, $unconverted_sizes, 'All 4 sizes should be converted');
 		$this->assertCount(4, $unprocessed_sizes, 'All sizes should be processed');
 	}
+
+	/**
+	 * Test conversion to see if follow-up conversion will be done with the same mimetype
+	 */
+	public function test_conversion_same_mimetype()
+	{
+		$this->wp->addOption('tinypng_convert_format', array(
+			'convert' => 'on',
+			'convert_to' => 'smallest',
+		));
+		$this->wp->addOption('tinypng_sizes', array(
+			Tiny_Image::ORIGINAL => 'on',
+			'thumbnail' => 'on',
+		));
+		$this->wp->createImages(array(
+			'thumbnail' => 1000,
+		));
+		$this->wp->stub('get_post_mime_type', function () {
+			return 'image/png';
+		});
+
+		$metadata = $this->wp->getTestMetadata();
+		$settings = new Tiny_Settings();
+
+		// create a mock compressor to spy on calls
+		$mock_compressor = $this->createMock(Tiny_Compress::class);
+
+		// we expect for all sizes a webp
+		$converted_type = 'image/webp';
+		$responses = array(
+			array(
+				'input' => array('size' => 1000),
+				'output' => array('size' => 800, 'type' => 'image/png'),
+				'convert' => array('type' => $converted_type, 'size' => 750, 'path' => 'vfs://root/converted-1.webp'),
+			),
+			array(
+				'input' => array('size' => 1000),
+				'output' => array('size' => 780, 'type' => 'image/png'),
+				'convert' => array('type' => $converted_type, 'size' => 720, 'path' => 'vfs://root/converted-2.webp'),
+			),
+		);
+
+		$compress_calls = array();
+		$mock_compressor->expects($this->exactly(2))
+			->method('compress_file')
+			->willReturnCallback(function ($file, $resize, $preserve, $convert_to) use (&$compress_calls, &$responses) {
+				$compress_calls[] = array(
+					'file' => $file,
+					'convert_to' => $convert_to,
+				);
+				return array_shift($responses);
+			});
+		$settings->set_compressor($mock_compressor);
+
+		$tinyimg = new Tiny_Image($settings, 999, $metadata);
+		$tinyimg->compress();
+
+		// should have been 2 calls to our mock 'compress_file'
+		$this->assertCount(2, $compress_calls);
+
+		// first call would have been width all mimetypes
+		$this->assertEquals(array('image/avif', 'image/webp'), $compress_calls[0]['convert_to']);
+
+		// second call should be only with image/webp because first call was a image/webp
+		$this->assertEquals(array('image/webp'), $compress_calls[1]['convert_to']);
+	}
 }