Added autoloader to reduce complexity; fix phpcs issues

.dev-lib

@@ -1 +1,5 @@
-SYNC_README_MD=0
+SYNC_README_MD=0
+PATH_EXCLUDES_PATTERN=includes/lib/*
+
+# Temporary to avoid having to fix all phpcs issues for touched files in <https://github.com/Automattic/amp-wp/pull/828>.
+DEV_LIB_SKIP=phpcs

amp.php

@@ -17,16 +17,10 @@
 define( 'AMP__DIR__', dirname( __FILE__ ) );
 define( 'AMP__VERSION', '0.6.0-alpha' );
 
+require_once AMP__DIR__ . '/autoloader.php';
 require_once AMP__DIR__ . '/back-compat/back-compat.php';
 require_once AMP__DIR__ . '/includes/amp-helper-functions.php';
-require_once AMP__DIR__ . '/includes/class-amp-post-type-support.php';
 require_once AMP__DIR__ . '/includes/admin/functions.php';
-require_once AMP__DIR__ . '/includes/admin/class-amp-customizer.php';
-require_once AMP__DIR__ . '/includes/admin/class-amp-post-meta-box.php';
-require_once AMP__DIR__ . '/includes/settings/class-amp-customizer-settings.php';
-require_once AMP__DIR__ . '/includes/settings/class-amp-customizer-design-settings.php';
-require_once AMP__DIR__ . '/includes/actions/class-amp-frontend-actions.php';
-require_once AMP__DIR__ . '/includes/actions/class-amp-paired-post-actions.php';
 
 register_activation_hook( __FILE__, 'amp_activate' );
 function amp_activate() {
@@ -150,7 +144,7 @@ function amp_maybe_add_actions() {
 }
 
 function amp_load_classes() {
-	require_once( AMP__DIR__ . '/includes/class-amp-post-template.php' ); // this loads everything else
+	_deprecated_function( __FUNCTION__, '0.6.0' );
 }
 
 function amp_add_frontend_actions() {
@@ -196,8 +190,6 @@ function amp_render_post( $post ) {
 	}
 	$post_id = $post->ID;
 
-	amp_load_classes();
-
 	/**
 	 * Fires before rendering a post in AMP.
 	 *
@@ -249,6 +241,5 @@ function amp_redirect_old_slug_to_new_url( $link ) {
 
 // Unconditionally load code required when running unit tests.
 if ( function_exists( 'tests_add_filter' ) ) {
-	amp_load_classes();
 	require_once dirname( __FILE__ ) . '/tests/stubs.php';
 }

autoloader.php

@@ -0,0 +1,141 @@
+<?php
+
+/**
+ * Autoload the classes used by the AMP plugin.
+ *
+ * Class AMP_Autoloader
+ */
+class AMP_Autoloader {
+
+	/**
+	 * Map of Classname to relative filepath sans extension.
+	 *
+	 * @note We omitted the leading slash and the .php extension from each
+	 *       relative filepath because they are redundant and to include
+	 *       them would take up unnecessary bytes of memory at runtime.
+	 *
+	 * @example Format (note no leading / and no .php extension):
+	 *
+	 *  array(
+	 *      'Class_Name1' =>  'subdir-of-includes/filename1',
+	 *      'Class_Name2' =>  '2nd-subdir-of-includes/filename2',
+	 *      'Class_Name3' =>  '!/full/path/to/filename3.php',
+	 *  );
+	 *
+	 * @var string[]
+	 */
+	private static $_classmap = array(
+		'AMP_Actions'                                                    => 'actions/class-amp-actions',
+		'AMP_Frontend_Actions'                                           => 'actions/class-amp-frontend-actions',
+		'AMP_Paired_Post_Actions'                                        => 'actions/class-amp-paired-post-actions',
+		'AMP_Template_Customizer'                                        => 'admin/class-amp-customizer',
+		'AMP_Post_Meta_Box'                                              => 'admin/class-amp-post-meta-box',
+		'AMP_Post_Type_Support'                                          => 'class-amp-post-type-support',
+		'AMP_Base_Embed_Handler'                                         => 'embeds/class-amp-base-embed-handler',
+		'AMP_DailyMotion_Embed_Handler'                                  => 'embeds/class-amp-dailymotion-embed',
+		'AMP_Facebook_Embed_Handler'                                     => 'embeds/class-amp-facebook-embed',
+		'AMP_Gallery_Embed_Handler'                                      => 'embeds/class-amp-gallery-embed',
+		'AMP_Instagram_Embed_Handler'                                    => 'embeds/class-amp-instagram-embed',
+		'AMP_Pinterest_Embed_Handler'                                    => 'embeds/class-amp-pinterest-embed',
+		'AMP_SoundCloud_Embed_Handler'                                   => 'embeds/class-amp-soundcloud-embed',
+		'AMP_Twitter_Embed_Handler'                                      => 'embeds/class-amp-twitter-embed',
+		'AMP_Vimeo_Embed_Handler'                                        => 'embeds/class-amp-vimeo-embed',
+		'AMP_Vine_Embed_Handler'                                         => 'embeds/class-amp-vine-embed',
+		'AMP_YouTube_Embed_Handler'                                      => 'embeds/class-amp-youtube-embed',
+		'FastImage'                                                      => 'lib/fastimage/class-fastimage',
+		'WillWashburn\\Stream\\Exception\\StreamBufferTooSmallException' => 'lib/fasterimage/Stream/Exception/StreamBufferTooSmallException',
+		'WillWashburn\\Stream\\StreamableInterface'                      => 'lib/fasterimage/Stream/StreamableInterface',
+		'WillWashburn\\Stream\\Stream'                                   => 'lib/fasterimage/Stream/Stream',
+		'FasterImage\\Exception\\InvalidImageException'                  => 'lib/fasterimage/Exception/InvalidImageException',
+		'FasterImage\\ExifParser'                                        => 'lib/fasterimage/ExifParser',
+		'FasterImage\\ImageParser'                                       => 'lib/fasterimage/ImageParser',
+		'FasterImage\\FasterImage'                                       => 'lib/fasterimage/FasterImage',
+		'AMP_Analytics_Options_Submenu'                                  => 'options/class-amp-analytics-options-submenu',
+		'AMP_Options_Menu'                                               => 'options/class-amp-options-menu',
+		'AMP_Options_Manager'                                            => 'options/class-amp-options-manager',
+		'AMP_Analytics_Options_Submenu_Page'                             => 'options/views/class-amp-analytics-options-submenu-page',
+		'AMP_Options_Menu_Page'                                          => 'options/views/class-amp-options-menu-page',
+		'AMP_Rule_Spec'                                                  => 'sanitizers/class-amp-rule-spec',
+		'AMP_Allowed_Tags_Generated'                                     => 'sanitizers/class-amp-allowed-tags-generated',
+		'AMP_Audio_Sanitizer'                                            => 'sanitizers/class-amp-audio-sanitizer',
+		'AMP_Base_Sanitizer'                                             => 'sanitizers/class-amp-base-sanitizer',
+		'AMP_Blacklist_Sanitizer'                                        => 'sanitizers/class-amp-blacklist-sanitizer',
+		'AMP_Iframe_Sanitizer'                                           => 'sanitizers/class-amp-iframe-sanitizer',
+		'AMP_Img_Sanitizer'                                              => 'sanitizers/class-amp-img-sanitizer',
+		'AMP_Playbuzz_Sanitizer'                                         => 'sanitizers/class-amp-playbuzz-sanitizer',
+		'AMP_Style_Sanitizer'                                            => 'sanitizers/class-amp-style-sanitizer',
+		'AMP_Tag_And_Attribute_Sanitizer'                                => 'sanitizers/class-amp-tag-and-attribute-sanitizer',
+		'AMP_Video_Sanitizer'                                            => 'sanitizers/class-amp-video-sanitizer',
+		'AMP_Customizer_Design_Settings'                                 => 'settings/class-amp-customizer-design-settings',
+		'AMP_Customizer_Settings'                                        => 'settings/class-amp-customizer-settings',
+		'AMP_Content'                                                    => 'templates/class-amp-content',
+		'AMP_Content_Sanitizer'                                          => 'templates/class-amp-content-sanitizer',
+		'AMP_Post_Template'                                              => 'templates/class-amp-post-template',
+		'AMP_DOM_Utils'                                                  => 'utils/class-amp-dom-utils',
+		'AMP_HTML_Utils'                                                 => 'utils/class-amp-html-utils',
+		'AMP_Image_Dimension_Extractor'                                  => 'utils/class-amp-image-dimension-extractor',
+		'AMP_String_Utils'                                               => 'utils/class-amp-string-utils',
+		'AMP_WP_Utils'                                                   => 'utils/class-amp-wp-utils',
+		'WPCOM_AMP_Polldaddy_Embed'                                      => 'wpcom/class-amp-polldaddy-embed',
+	);
+
+	/**
+	 * Is registered.
+	 *
+	 * @var bool
+	 */
+	public static $is_registered = false;
+
+	/**
+	 * Perform the autoload on demand when requested by PHP runtime.
+	 *
+	 * Design Goal: Execute as few lines of code as possible each call.
+	 *
+	 * @since 0.6.0
+	 *
+	 * @note If $class_name has first char as '!' strip it and assume
+	 *       a full path with extension otherwise assume a subdir of
+	 *       /includes/ that does not contain an extension.
+	 *
+	 * @param string $class_name Class name.
+	 */
+	protected static function autoload( $class_name ) {
+		if ( ! isset( self::$_classmap[ $class_name ] ) ) {
+			return;
+		}
+		$filepath = self::$_classmap[ $class_name ];
+		require '!' !== $filepath[0] ? dirname( __FILE__ ) . "/includes/{$filepath}.php" : substr( $filepath, 1 );
+	}
+
+	/**
+	 * Registers this autoloader to PHP.
+	 *
+	 * @since 0.6.0
+	 *
+	 * Called at the end of this file; calling a second time has no effect.
+	 */
+	public static function register() {
+		if ( ! self::$is_registered ) {
+			spl_autoload_register( array( __CLASS__, 'autoload' ) );
+			self::$is_registered = true;
+		}
+	}
+
+	/**
+	 * Allows an extensions plugin to register a class and its file for autoloading
+	 *
+	 * @since 0.6.0
+	 *
+	 * @param string $class_name Full classname (include namespace if applicable).
+	 * @param string $filepath   Absolute filepath to class file, including .php extension.
+	 */
+	public static function register_autoload_class( $class_name, $filepath ) {
+		self::$_classmap[ $class_name ] = '!' . $filepath;
+	}
+
+}
+
+/**
+ * Call method to register this autoloader with PHP.
+ */
+AMP_Autoloader::register();

composer.json

@@ -0,0 +1,7 @@
+{
+    "name": "automattic/amp-wp",
+    "description": "WordPress plugin for adding AMP support.",
+    "homepage": "https://github.com/Automattic/amp-wp",
+    "type": "wordpress-plugin",
+    "license": "GPL-2.0"
+}

includes/actions/class-amp-frontend-actions.php

@@ -1,7 +1,6 @@
 <?php
 // Callbacks for adding AMP-related things to the main theme
 
-require_once( AMP__DIR__ . '/includes/actions/class-amp-actions.php' );
 
 class AMP_Frontend_Actions {
 

includes/actions/class-amp-paired-post-actions.php

@@ -1,7 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/actions/class-amp-actions.php' );
-
 class AMP_Paired_Post_Actions extends AMP_Actions {
 
 	public static function register_hooks() {

includes/admin/functions.php

@@ -1,9 +1,6 @@
 <?php
 // Callbacks for adding AMP-related things to the admin.
 
-require_once AMP__DIR__ . '/includes/options/class-amp-options-menu.php';
-require_once AMP__DIR__ . '/includes/options/views/class-amp-options-manager.php';
-
 define( 'AMP_CUSTOMIZER_QUERY_VAR', 'customize_amp' );
 
 /**
@@ -31,6 +28,11 @@ function amp_maybe_init_customizer() {
 	add_action( 'admin_menu', 'amp_add_customizer_link' );
 }
 
+/**
+ * Get permalink for the first AMP-eligible post.
+ *
+ * @return string|null
+ */
 function amp_admin_get_preview_permalink() {
 	/**
 	 * Filter the post type to retrieve the latest for use in the AMP template customizer.
@@ -40,7 +42,7 @@ function amp_admin_get_preview_permalink() {
 	$post_type = (string) apply_filters( 'amp_customizer_post_type', 'post' );
 
 	if ( ! post_type_supports( $post_type, 'amp' ) ) {
-		return;
+		return null;
 	}
 
 	$post_ids = get_posts( array(

includes/amp-helper-functions.php

@@ -1,11 +1,12 @@
 <?php
 
 /**
- * Get AMP permalink.
+ * Retrieves the full AMP-specific permalink for the given post ID.
  *
  * @since 0.1
  *
  * @param int $post_id Post ID.
+ *
  * @return string AMP permalink.
  */
 function amp_get_permalink( $post_id ) {

includes/embeds/class-amp-base-embed-handler.php

@@ -1,8 +1,15 @@
 <?php
+/**
+ * Class AMP_Base_Embed_Handler
+ *
+ * Used by some children.
+ *
+ * @package  AMP
+ */
 
-// Used by some children
-require_once( AMP__DIR__ . '/includes/utils/class-amp-html-utils.php' );
-
+/**
+ * Class AMP_Base_Embed_Handler
+ */
 abstract class AMP_Base_Embed_Handler {
 	protected $DEFAULT_WIDTH = 600;
 	protected $DEFAULT_HEIGHT = 480;

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 // Much of this class is borrowed from Jetpack embeds
 class AMP_DailyMotion_Embed_Handler extends AMP_Base_Embed_Handler {

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 class AMP_Facebook_Embed_Handler extends AMP_Base_Embed_Handler {
 	const URL_PATTERN = '#https?://(www\.)?facebook\.com/.*#i';

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 class AMP_Gallery_Embed_Handler extends AMP_Base_Embed_Handler {
 	private static $script_slug = 'amp-carousel';

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 // Much of this class is borrowed from Jetpack embeds
 class AMP_Instagram_Embed_Handler extends AMP_Base_Embed_Handler {

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php');
 
 class AMP_Pinterest_Embed_Handler extends AMP_Base_Embed_Handler {
 

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 class AMP_SoundCloud_Embed_Handler extends AMP_Base_Embed_Handler {
 	const URL_PATTERN = '#https?://api\.soundcloud\.com/tracks/.*#i';

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 // Much of this class is borrowed from Jetpack embeds
 class AMP_Twitter_Embed_Handler extends AMP_Base_Embed_Handler {

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 // Much of this class is borrowed from Jetpack embeds
 class AMP_Vimeo_Embed_Handler extends AMP_Base_Embed_Handler {

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 class AMP_Vine_Embed_Handler extends AMP_Base_Embed_Handler {
 	const URL_PATTERN = '#https?://vine\.co/v/([^/?]+)#i';

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

@@ -1,6 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/embeds/class-amp-base-embed-handler.php' );
 
 // Much of this class is borrowed from Jetpack embeds
 class AMP_YouTube_Embed_Handler extends AMP_Base_Embed_Handler {

includes/lib/fasterimage/amp-fasterimage.php

@@ -1,25 +1,9 @@
 <?php
 
 function amp_load_fasterimage_classes() {
-	// We're not using composer to pull in FasterImage so we need to load the files manually
-	$fasterimage__DIR__ = dirname( __FILE__ );
-
-	// Stream files
-	require_once( $fasterimage__DIR__ . '/Stream/Exception/StreamBufferTooSmallException.php' );
-	require_once( $fasterimage__DIR__ . '/Stream/StreamableInterface.php' );
-	require_once( $fasterimage__DIR__ . '/Stream/Stream.php' );
-
-	// FasterImage files
-	require_once( $fasterimage__DIR__ . '/Exception/InvalidImageException.php' );
-	require_once( $fasterimage__DIR__ . '/ExifParser.php' );
-	require_once( $fasterimage__DIR__ . '/ImageParser.php' );
-	require_once( $fasterimage__DIR__ . '/FasterImage.php' );
+	_deprecated_function( __FUNCTION__, '0.6.0' );
 }
 
 function amp_get_fasterimage_client( $user_agent ) {
-	if ( ! class_exists( 'FasterImage\FasterImage' ) ) {
-		amp_load_fasterimage_classes();
-	}
-
 	return new FasterImage\FasterImage( $user_agent );
 }

includes/options/class-amp-analytics-options-submenu.php

@@ -1,7 +1,5 @@
 <?php
 
-require_once( AMP__DIR__ . '/includes/options/views/class-amp-analytics-options-submenu-page.php' );
-require_once( AMP__DIR__ . '/includes/utils/class-amp-html-utils.php' );
 
 class AMP_Analytics_Options_Submenu {