Preserve image attributes when cropping a custom logo image

src/wp-admin/includes/ajax-actions.php

@@ -3975,18 +3975,34 @@ function wp_ajax_crop_image() {
 
 			$size       = wp_getimagesize( $cropped );
 			$image_type = ( $size ) ? $size['mime'] : 'image/jpeg';
+			/** @var WP_Post $original_attachment */
+			$original_attachment = get_post( $attachment_id );
+			$has_title           = 0 < mb_strlen( trim( $original_attachment->post_title ) );
+			$has_description     = 0 < mb_strlen( trim( $original_attachment->post_content ) );
 
 			$object = array(
-				'post_title'     => wp_basename( $cropped ),
-				'post_content'   => $url,
+				// Copy the image title attribute (post_content field) from the original image.
+				'post_title'     => $has_title ? $original_attachment->post_title : wp_basename( $cropped ),
+				// Copy the image description attribute (post_content field) from the original image.
+				'post_content'   => $has_description ? $original_attachment->post_content : $url,
 				'post_mime_type' => $image_type,
 				'guid'           => $url,
 				'context'        => $context,
 			);
 
+			// Copy the image caption attribute (post_excerpt field) from the original image.
+			if ( mb_strlen( trim( $original_attachment->post_excerpt ) ) ) {
+				$object['post_excerpt'] = $original_attachment->post_excerpt;
+			}
+
 			$attachment_id = wp_insert_attachment( $object, $cropped );
 			$metadata      = wp_generate_attachment_metadata( $attachment_id, $cropped );
 
+			// Copy the image alt text attribute from the original image.
+			if ( mb_strlen( trim( $original_attachment->_wp_attachment_image_alt ) ) ) {
+				update_post_meta( $attachment_id, '_wp_attachment_image_alt', wp_slash( $original_attachment->_wp_attachment_image_alt ) );
+			}
+
 			/**
 			 * Filters the cropped image attachment metadata.
 			 *

tests/phpunit/tests/ajax/CropImage.php

@@ -0,0 +1,150 @@
+<?php
+
+/**
+ * Admin Ajax functions to be tested.
+ */
+require_once ABSPATH . 'wp-admin/includes/ajax-actions.php';
+
+require_once ABSPATH . 'wp-admin/includes/class-wp-filesystem-base.php';
+require_once ABSPATH . 'wp-admin/includes/class-wp-filesystem-direct.php';
+
+/**
+ * Class for testing ajax crop image functionality.
+ *
+ * @group ajax
+ */
+class Tests_Ajax_CropImage extends WP_Ajax_UnitTestCase {
+
+	/**
+	 * @covers wp_ajax_crop_image
+	 */
+	public function test_it_copies_metadata_from_original_image() {
+
+		// Become an administrator.
+		$this->_setRole( 'administrator' );
+
+		$attachment = $this->create_attachment( true );
+		$this->prepare_post( $attachment );
+
+		// Make the request.
+		try {
+			$this->_handleAjax( 'crop-image' );
+		} catch ( WPAjaxDieContinueException $e ) {
+		}
+
+		$response = json_decode( $this->_last_response, true );
+		$this->validate_response( $response );
+
+		$cropped_attachment = get_post( $response['data']['id'] );
+		$this->assertInstanceOf( WP_Post::class, $cropped_attachment );
+		$this->assertNotEmpty( $attachment->post_title );
+		$this->assertNotEmpty( $cropped_attachment->post_title );
+		$this->assertSame( $attachment->post_title, $cropped_attachment->post_title );
+		$this->assertSame( $attachment->post_content, $cropped_attachment->post_content );
+		$this->assertSame( $attachment->post_excerpt, $cropped_attachment->post_excerpt );
+		$this->assertSame( $attachment->_wp_attachment_image_alt, $cropped_attachment->_wp_attachment_image_alt );
+
+		wp_delete_attachment( $attachment->ID, true );
+		wp_delete_attachment( $cropped_attachment->ID, true );
+	}
+
+	/**
+	 * @covers wp_ajax_crop_image
+	 */
+	public function test_it_doesnt_generate_new_metadata_if_metadata_is_empty() {
+		// Become an administrator.
+		$this->_setRole( 'administrator' );
+
+		$attachment = $this->create_attachment( false );
+		$this->prepare_post( $attachment );
+
+		// Make the request.
+		try {
+			$this->_handleAjax( 'crop-image' );
+		} catch ( WPAjaxDieContinueException $e ) {
+		}
+
+		$response = json_decode( $this->_last_response, true );
+		$this->validate_response( $response );
+
+		$cropped_attachment = get_post( $response['data']['id'] );
+		$this->assertInstanceOf( WP_Post::class, $cropped_attachment );
+		$this->assertEmpty( $attachment->post_title );
+		$this->assertNotEmpty( $cropped_attachment->post_title );
+		$this->assertStringStartsWith( 'http', $cropped_attachment->post_content );
+		$this->assertEmpty( $cropped_attachment->post_excerpt );
+		$this->assertEmpty( $cropped_attachment->_wp_attachment_image_alt );
+
+		wp_delete_attachment( $attachment->ID, true );
+		wp_delete_attachment( $cropped_attachment->ID, true );
+	}
+
+	/**
+	 * Creates an attachment.
+	 *
+	 * @return WP_Post
+	 */
+	private function create_attachment( $with_metadata = true ) {
+		$uniq_id = uniqid( 'crop-image-ajax-action-test-' );
+		$object  = array(
+			'post_title'     => $with_metadata ? 'Title ' . $uniq_id : '',
+			'post_content'   => $with_metadata ? 'Description ' . $uniq_id : '',
+			'post_mime_type' => 'image/jpg',
+			'guid'           => 'http://localhost/foo.jpg',
+			'context'        => 'custom-logo',
+			'post_excerpt'   => $with_metadata ? 'Caption ' . $uniq_id : '',
+		);
+
+		$test_file        = DIR_TESTDATA . '/images/test-image.jpg';
+		$upload_directory = wp_upload_dir();
+		$uploaded_file    = $upload_directory['path'] . '/' . $uniq_id . '.jpg';
+		$filesystem       = new WP_Filesystem_Direct( true );
+		$filesystem->copy( $test_file, $uploaded_file );
+		$attachment_id = wp_insert_attachment( $object, $uploaded_file );
+
+		if ( $with_metadata ) {
+			update_post_meta( $attachment_id, '_wp_attachment_image_alt', wp_slash( 'Alt ' . $uniq_id ) );
+		}
+
+		return get_post( $attachment_id );
+	}
+
+	/**
+	 * @param array $response Response to validate.
+	 *
+	 * @return void
+	 */
+	private function validate_response( $response ) {
+		$this->assertArrayHasKey( 'success', $response );
+		$this->assertArrayHasKey( 'data', $response );
+		$this->assertNotEmpty( $response['data']['id'] );
+	}
+
+	/**
+	 * Prepares $_POST for crop-image ajax action.
+	 *
+	 * @param WP_Post $attachment
+	 *
+	 * @return void
+	 */
+	private function prepare_post( WP_Post $attachment ) {
+		$_POST = array(
+			'wp_customize' => 'on',
+			'nonce'        => wp_create_nonce( 'image_editor-' . $attachment->ID ),
+			'id'           => $attachment->ID,
+			'context'      => 'custom_logo',
+			'cropDetails'  =>
+				array(
+					'x1'         => '0',
+					'y1'         => '0',
+					'x2'         => '100',
+					'y2'         => '100',
+					'width'      => '100',
+					'height'     => '100',
+					'dst_width'  => '100',
+					'dst_height' => '100',
+				),
+			'action'       => 'crop-image',
+		);
+	}
+}