Address issues from testing with WordPress 5.0

includes/embeds/class-amp-gallery-embed.php

@@ -17,6 +17,7 @@ class AMP_Gallery_Embed_Handler extends AMP_Base_Embed_Handler {
 	 */
 	public function register_embed() {
 		add_filter( 'post_gallery', array( $this, 'maybe_override_gallery' ), 10, 2 );
+		add_action( 'wp_print_styles', array( $this, 'print_styles' ) );
 	}
 
 	/**
@@ -160,6 +161,15 @@ public function maybe_override_gallery( $html, $attributes ) {
 			}
 
 			return $html;
+		} elseif ( isset( $attributes['size'] ) && 'thumbnail' === $attributes['size'] ) {
+			/*
+			 * If the 'gallery' shortcode has a 'size' attribute of 'thumbnail', prevent outputting an <amp-carousel>.
+			 * That will often get thumbnail images around 150 x 150,
+			 * while the <amp-carousel> usually has a width of 600 and a height of 480.
+			 * That often means very low-resolution images.
+			 * So fall back to the normal 'gallery' shortcode callback, gallery_shortcode().
+			 */
+			return '';
 		}
 		return $this->shortcode( $attributes );
 	}
@@ -224,4 +234,25 @@ public function render( $args ) {
 			implode( PHP_EOL, $images )
 		);
 	}
+
+	/**
+	 * Prints the Gallery block styling.
+	 *
+	 * It would be better to print this in AMP_Gallery_Block_Sanitizer,
+	 * but by the time that runs, it's too late.
+	 * This rule is copied exactly from block-library/style.css, but the selector here has amp-img >.
+	 * The image sanitizer normally converts the <img> from that original stylesheet <amp-img>,
+	 * but that doesn't have the same effect as applying it to the <img>.
+	 *
+	 * @return void
+	 */
+	public function print_styles() {
+		?>
+		<style>
+			.wp-block-gallery.is-cropped .blocks-gallery-item amp-img > img {
+				object-fit: cover;
+			}
+		</style>
+		<?php
+	}
 }

includes/sanitizers/class-amp-core-theme-sanitizer.php

@@ -53,17 +53,20 @@ class AMP_Core_Theme_Sanitizer extends AMP_Base_Sanitizer {
 	protected static $theme_features = array(
 		// Twenty Nineteen.
 		'twentynineteen'  => array(
-			'dequeue_scripts'                    => array(
+			'dequeue_scripts'                             => array(
 				'twentynineteen-skip-link-focus-fix', // This is part of AMP. See <https://github.com/ampproject/amphtml/issues/18671>.
 				'twentynineteen-priority-menu',
 				'twentynineteen-touch-navigation', // @todo There could be an AMP implementation of this, similar to what is implemented on ampproject.org.
 			),
-			'remove_actions'                     => array(
+			'remove_actions'                              => array(
 				'wp_print_footer_scripts' => array(
 					'twentynineteen_skip_link_focus_fix', // See <https://github.com/WordPress/twentynineteen/pull/47>.
 				),
 			),
-			'add_twentynineteen_masthead_styles' => array(),
+			'add_twentynineteen_masthead_styles'          => array(),
+			'add_twentynineteen_image_styles'             => array(),
+			'remove_twentynineteen_thumbnail_image_sizes' => array(),
+
 		),
 
 		// Twenty Seventeen.
@@ -341,6 +344,26 @@ public static function set_twentyseventeen_quotes_icon() {
 		} );
 	}
 
+	/**
+	 * Remove the sizes attribute from thumbnail images in Twenty Nineteen.
+	 *
+	 * The AMP runtime sets an inline style on an <amp-img> based on the sizes attribute if it's present.
+	 * For example, <amp-img style="width:calc(50vw)">.
+	 * Removing the 'sizes' attribute isn't ideal, but it looks like it's not possible to override that inline style.
+	 *
+	 * @todo: remove when this is resolved: https://github.com/ampproject/amphtml/issues/17053
+	 * @since 1.0
+	 */
+	public static function remove_twentynineteen_thumbnail_image_sizes() {
+		add_filter( 'wp_get_attachment_image_attributes', function( $attr ) {
+			if ( isset( $attr['class'] ) && false !== strpos( $attr['class'], 'attachment-post-thumbnail' ) ) {
+				unset( $attr['sizes'] );
+			}
+
+			return $attr;
+		}, 11 );
+	}
+
 	/**
 	 * Add filter to adjust the attachment image attributes to ensure attachment pages have a consistent <amp-img> rendering.
 	 *
@@ -1056,4 +1079,29 @@ public static function add_nav_sub_menu_buttons( $args = array() ) {
 			return $item_output;
 		}, 10, 4 );
 	}
+
+	/**
+	 * Output image styles for twentynineteen.
+	 *
+	 * When <img> tags have an 'aligncenter' class, AMP_Img_Sanitizer::handle_centering() wraps theme in <figure class="aligncenter">.
+	 * This ensures that the image inside it is centered.
+	 *
+	 * @since 1.0
+	 *
+	 * @param array $args Arguments.
+	 */
+	public static function add_twentynineteen_image_styles( $args = array() ) {
+		add_action( 'wp_enqueue_scripts', function() use ( $args ) {
+			ob_start();
+			?>
+			<style>
+				figure.aligncenter {
+					text-align: center
+				}
+			</style>
+			<?php
+			$styles = str_replace( array( '<style>', '</style>' ), '', ob_get_clean() );
+			wp_add_inline_style( get_template() . '-style', $styles );
+		}, 11 );
+	}
 }

readme.md

@@ -7,7 +7,7 @@ Enable Accelerated Mobile Pages (AMP) on your WordPress site.
 **Contributors:** [batmoo](https://profiles.wordpress.org/batmoo), [joen](https://profiles.wordpress.org/joen), [automattic](https://profiles.wordpress.org/automattic), [potatomaster](https://profiles.wordpress.org/potatomaster), [albertomedina](https://profiles.wordpress.org/albertomedina), [google](https://profiles.wordpress.org/google), [xwp](https://profiles.wordpress.org/xwp), [westonruter](https://profiles.wordpress.org/westonruter)  
 **Tags:** [amp](https://wordpress.org/plugins/tags/amp), [mobile](https://wordpress.org/plugins/tags/mobile)  
 **Requires at least:** 4.7  
-**Tested up to:** 4.9  
+**Tested up to:** 5.0  
 **Stable tag:** 0.7.2  
 **License:** [GPLv2 or later](http://www.gnu.org/licenses/gpl-2.0.html)  
 **Requires PHP:** 5.3.6  

readme.txt

@@ -2,7 +2,7 @@
 Contributors: batmoo, joen, automattic, potatomaster, albertomedina, google, xwp, westonruter
 Tags: amp, mobile
 Requires at least: 4.7
-Tested up to: 4.9
+Tested up to: 5.0
 Stable tag: 0.7.2
 License: GPLv2 or later
 License URI: http://www.gnu.org/licenses/gpl-2.0.html