Unit tests and coding standards

Updates JS to accommodate both Gutenberg and the Classic editor. Also introduces unit tests and conforms to coding standards.

Fixes #2 (closed) Fixes #3 (closed)

inc/class-wp-revisions-control.php

+<?php
+/**
+ * Main plugin functionality.
+ *
+ * @package WP_Revisions_Control
+ */
+
+/**
+ * Class WP_Revisions_Control.
+ */
+class WP_Revisions_Control {
+	/**
+	 * Singleton
+	 */
+	private static $__instance = null;
+
+	/**
+	 * Class variables
+	 */
+	private static $priority = null; // use $this->plugin_priority()
+	private $priority_default = 50;
+
+	private static $post_types = array(); // use $this->get_post_types()
+	private static $settings = array(); // use $this->get_settings()
+
+	private $settings_page = 'writing';
+	private $settings_section = 'wp_revisions_control';
+
+	private $meta_key_limit = '_wp_rev_ctl_limit';
+
+	/**
+	 * Silence is golden!
+	 */
+	private function __construct() {}
+
+	/**
+	 * Singleton implementation
+	 *
+	 * @uses self::setup
+	 * @return object
+	 */
+	public static function get_instance() {
+		if ( ! is_a( self::$__instance, __CLASS__ ) ) {
+			self::$__instance = new self;
+
+			self::$__instance->setup();
+		}
+
+		return self::$__instance;
+	}
+
+	/**
+	 * Register actions and filters at `init` so others can interact, if desired.
+	 *
+	 * @uses add_action
+	 * @return null
+	 */
+	private function setup() {
+		add_action( 'plugins_loaded', array( $this, 'action_plugins_loaded' ) );
+		add_action( 'init', array( $this, 'action_init' ) );
+	}
+
+	/**
+	 * Load plugin translations
+	 *
+	 * @uses load_plugin_textdomain
+	 * @uses plugin_basename
+	 * @action plugins_loaded
+	 * @return null
+	 */
+	public function action_plugins_loaded() {
+		load_plugin_textdomain( 'wp_revisions_control', false, dirname( plugin_basename( __FILE__ ) ) . '/languages/' );
+	}
+
+	/**
+	 * Register actions and filters
+	 *
+	 * @uses add_action
+	 * @uses add_filter
+	 * @uses this::plugin_priority
+	 * @return null
+	 */
+	public function action_init() {
+		add_action( 'admin_init', array( $this, 'action_admin_init' ) );
+
+		add_filter( 'wp_revisions_to_keep', array( $this, 'filter_wp_revisions_to_keep' ), $this->plugin_priority(), 2 );
+	}
+
+	/**
+	 * Register plugin's admin-specific elements
+	 *
+	 * Plugin title is intentionally not translatable.
+	 *
+	 * @uses register_setting
+	 * @uses add_settings_section
+	 * @uses __
+	 * @uses this::get_post_types
+	 * @uses add_settings_field
+	 * @action admin_init
+	 * @return null
+	 */
+	public function action_admin_init() {
+		// Plugin setting section
+		register_setting( $this->settings_page, $this->settings_section, array( $this, 'sanitize_options' ) );
+
+		add_settings_section( $this->settings_section, 'WP Revisions Control', array( $this, 'settings_section_intro' ), $this->settings_page );
+
+		foreach ( $this->get_post_types() as $post_type => $name ) {
+			add_settings_field( $this->settings_section . '-' . $post_type, $name, array( $this, 'field_post_type' ), $this->settings_page, $this->settings_section, array( 'post_type' => $post_type ) );
+		}
+
+		// Post-level functionality
+		add_action( 'add_meta_boxes', array( $this, 'action_add_meta_boxes' ), 10, 2 );
+		add_action( 'wp_ajax_' . $this->settings_section . '_purge', array( $this, 'ajax_purge' ) );
+		add_action( 'save_post', array( $this, 'action_save_post' ) );
+	}
+
+	/**
+	 ** PLUGIN SETTINGS SECTION
+	 ** FOUND UNDER SETTINGS > WRITING
+	 **/
+
+	/**
+	 * Display assistive text in settings section
+	 *
+	 * @uses _e
+	 * @uses this::plugin_priority
+	 * @return string
+	 */
+	public function settings_section_intro() {
+		?>
+		<p><?php _e( 'Set the number of revisions to save for each post type listed. To retain all revisions for a given post type, leave the field empty.', 'wp_revisions_control' ); ?></p>
+		<p><?php _e( "If a post type isn't listed, revisions are not enabled for that post type.", 'wp_revisions_control' ); ?></p>
+		<?php
+
+		// Display a note if the plugin priority is other than the default.
+		// Will be useful when debugging issues later.
+		if ( $this->plugin_priority() !== $this->priority_default ) : ?>
+			<p><?php printf( __( "A local change is causing this plugin's functionality to run at a priority other than the default. If you experience difficulties with the plugin, please unhook any functions from the %s filter.", 'wp_revisions_control' ), '<code>wp_revisions_control_priority</code>' ); ?></p>
+		<?php endif;
+	}
+
+	/**
+	 * Render field for each post type
+	 *
+	 * @param array $args
+	 * @uses this::get_revisions_to_keep
+	 * @uses esc_attr
+	 * @return string
+	 */
+	public function field_post_type( $args ) {
+		$revisions_to_keep = $this->get_revisions_to_keep( $args['post_type'], true );
+		?>
+		<input type="text" name="<?php echo esc_attr( $this->settings_section . '[' . $args['post_type'] . ']' ); ?>" value="<?php echo esc_attr( $revisions_to_keep ); ?>" class="small-text" />
+		<?php
+	}
+
+	/**
+	 * Sanitize plugin settings
+	 *
+	 * @param array $options
+	 * @return array
+	 */
+	public function sanitize_options( $options ) {
+		$options_sanitized = array();
+
+		if ( is_array( $options ) ) {
+			foreach ( $options as $post_type => $to_keep ) {
+				if ( 0 === strlen( $to_keep ) )
+					$to_keep = -1;
+				else
+					$to_keep = intval( $to_keep );
+
+				// Lowest possible value is -1, used to indicate infinite revisions are stored
+				if ( -1 > $to_keep )
+					$to_keep = -1;
+
+				$options_sanitized[ $post_type ] = $to_keep;
+			}
+		}
+
+		return $options_sanitized;
+	}
+
+	/**
+	 ** REVISIONS QUANTITY OVERRIDES
+	 **/
+
+	/**
+	 * Allow others to change the priority this plugin's functionality runs at
+	 *
+	 * @uses apply_filters
+	 * @return int
+	 */
+	private function plugin_priority() {
+		if ( is_null( self::$priority ) ) {
+			$plugin_priority = apply_filters( 'wp_revisions_control_priority', $this->priority_default );
+
+			self::$priority = is_numeric( $plugin_priority ) ? (int) $plugin_priority : $this->priority_default;
+		}
+
+		return self::$priority;
+	}
+
+	/**
+	 * Override number of revisions to keep using plugin's settings
+	 *
+	 * Can either be post-specific or universal
+	 *
+	 * @uses get_post_meta
+	 * @uses get_post_type
+	 * @uses this::get_settings
+	 * @filter wp_revisions_to_keep
+	 * @return mixed
+	 */
+	public function filter_wp_revisions_to_keep( $qty, $post ) {
+		$post_limit = get_post_meta( $post->ID, $this->meta_key_limit, true );
+
+		if ( 0 < strlen( $post_limit ) ) {
+			$qty = $post_limit;
+		} else {
+			$post_type = get_post_type( $post ) ? get_post_type( $post ) : $post->post_type;
+			$settings = $this->get_settings();
+
+			if ( array_key_exists( $post_type, $settings ) )
+				$qty = $settings[ $post_type ];
+		}
+
+		return $qty;
+	}
+
+	/**
+	 ** POST-LEVEL FUNCTIONALITY
+	 **/
+
+	/**
+	 * Override Core's revisions metabox
+	 *
+	 * @param string $post_type
+	 * @param object $post
+	 * @uses post_type_supports
+	 * @uses get_post_status
+	 * @uses wp_get_post_revisions
+	 * @uses remove_meta_box
+	 * @uses add_meta_box
+	 * @uses wp_enqueue_script
+	 * @uses plugins_url
+	 * @uses wp_localize_script
+	 * @uses wpautop
+	 * @uses add_action
+	 * @action add_meta_boxes
+	 * @return null
+	 */
+	public function action_add_meta_boxes( $post_type, $post ) {
+		if ( post_type_supports( $post_type, 'revisions' ) && 'auto-draft' != get_post_status() && count( wp_get_post_revisions( $post ) ) > 1 ) {
+			// Replace the metabox
+			remove_meta_box( 'revisionsdiv', null, 'normal' );
+			add_meta_box( 'revisionsdiv-wp-rev-ctl', __('Revisions', 'wp_revisions_control'), array( $this, 'revisions_meta_box' ), null, 'normal', 'core' );
+
+			// A bit of JS for us
+			$handle = 'wp-revisions-control-post';
+			wp_enqueue_script( $handle, plugins_url( 'js/post.js', __FILE__ ), array( 'jquery' ), '20131205', true );
+			wp_localize_script( $handle, $this->settings_section, array(
+				'namespace'       => $this->settings_section,
+				'action_base'     => $this->settings_section,
+				'processing_text' => __( 'Processing&hellip;', 'wp_revisions_control' ),
+				'ays'             => __( 'Are you sure you want to remove revisions from this post?', 'wp_revisions_control' ),
+				'autosave'        => __( 'Autosave', 'wp_revisions_control' ),
+				'nothing_text'    => wpautop( __( 'There are no revisions to remove.', 'wp_revisions_control' ) ),
+				'error'           => __( 'An error occurred. Please refresh the page and try again.', 'wp_revisions_control' )
+			) );
+
+			// Add some styling to our metabox additions
+			add_action( 'admin_head', array( $this, 'action_admin_head' ), 999 );
+		}
+	}
+
+	/**
+	 * Render Revisions metabox with plugin's additions
+	 *
+	 * @uses post_revisions_meta_box
+	 * @uses the_ID
+	 * @uses esc_attr
+	 * @uses wp_create_nonce
+	 * @uses this::get_post_revisions_to_keep
+	 * @uses wp_nonce_field
+	 * @return string
+	 */
+	public function revisions_meta_box( $post ) {
+		post_revisions_meta_box( $post );
+
+		?>
+		<div id="<?php echo esc_attr( $this->settings_section ); ?>">
+			<h4>WP Revisions Control</h4>
+
+			<p class="button purge" data-postid="<?php the_ID(); ?>" data-nonce="<?php echo esc_attr( wp_create_nonce( $this->settings_section . '_purge' ) ); ?>"><?php _e( 'Purge these revisions', 'wp_revisions_control' ); ?></p>
+
+			<p>
+				<?php printf( __( 'Limit this post to %s revisions. Leave this field blank for default behavior.', 'wp_revisions_control' ), '<input type="text" name="' . $this->settings_section . '_qty" value="' . $this->get_post_revisions_to_keep( $post->ID ) . '" id="' . $this->settings_section . '_qty" size="2" />' ); ?>
+
+				<?php wp_nonce_field( $this->settings_section . '_limit', $this->settings_section . '_limit_nonce', false ); ?>
+			</p>
+		</div><!-- #<?php echo esc_attr( $this->settings_section ); ?> -->
+		<?php
+	}
+
+	/**
+	 * Process a post-specific request to purge revisions
+	 *
+	 * @uses __
+	 * @uses check_ajax_referer
+	 * @uses current_user_can
+	 * @uses wp_get_post_revisions
+	 * @uses number_format_i18n
+	 * @return string
+	 */
+	public function ajax_purge() {
+		$post_id = isset( $_REQUEST['post_id'] ) ? (int) $_REQUEST['post_id'] : false;
+
+		// Hold the current state of this Ajax request
+		$response = array();
+
+		// Check for necessary data and capabilities
+		if ( ! $post_id )
+			$response['error'] = __( 'No post ID was provided. Please refresh the page and try again.', 'wp_revisions_control' );
+		elseif ( ! check_ajax_referer( $this->settings_section . '_purge', 'nonce', false ) )
+			$response['error'] = __( 'Invalid request. Please refresh the page and try again.', 'wp_revisions_control' );
+		elseif ( ! current_user_can( 'edit_post', $post_id ) )
+			$response['error'] = __( 'You are not allowed to edit this post.', 'wp_revisions_control' );
+
+		// Request is valid if $response is still empty, as no errors arose above
+		if ( empty( $response ) ) {
+			$revisions = wp_get_post_revisions( $post_id );
+
+			$count = count( $revisions );
+
+			foreach ( $revisions as $revision ) {
+				wp_delete_post_revision( $revision->ID );
+			}
+
+			$response['success'] = sprintf( __( 'Removed %s revisions associated with this post.', 'wp_revisions_control' ), number_format_i18n( $count, 0 ) );
+			$response['count'] = $count;
+		}
+
+		// Pass the response back to JS
+		echo json_encode( $response );
+		exit;
+	}
+
+	/**
+	 * Sanitize and store post-specifiy revisions quantity
+	 *
+	 * @uses wp_verify_nonce
+	 * @uses update_post_meta
+	 * @action save_post
+	 * @return null
+	 */
+	public function action_save_post( $post_id ) {
+		if ( isset( $_POST[ $this->settings_section . '_limit_nonce' ] ) && wp_verify_nonce( $_POST[ $this->settings_section . '_limit_nonce' ], $this->settings_section . '_limit' ) && isset( $_POST[ $this->settings_section . '_qty' ] ) ) {
+			$limit = $_POST[ $this->settings_section . '_qty' ];
+
+			if ( -1 == $limit || empty( $limit ) )
+				delete_post_meta( $post_id, $this->meta_key_limit );
+			else
+				update_post_meta( $post_id, $this->meta_key_limit, absint( $limit ) );
+		}
+	}
+
+	/**
+	 * Add a border between the regular revisions list and this plugin's additions
+	 *
+	 * @uses esc_attr
+	 * @action admin_head
+	 * @return string
+	 */
+	public function action_admin_head() {
+	?>
+		<style type="text/css">
+			#revisionsdiv-wp-rev-ctl #<?php echo esc_attr( $this->settings_section ); ?> {
+				 border-top: 1px solid #dfdfdf;
+				 padding-top: 0;
+				 margin-top: 20px;
+			}
+
+			#revisionsdiv-wp-rev-ctl #<?php echo esc_attr( $this->settings_section ); ?> h4 {
+				border-top: 1px solid #fff;
+				padding-top: 1.33em;
+				margin-top: 0;
+			}
+		</style>
+	<?php
+	}
+
+	/**
+	 ** PLUGIN UTILITIES
+	 **/
+
+	/**
+	 * Retrieve plugin settings
+	 *
+	 * @uses this::get_post_types
+	 * @uses get_option
+	 * @return array
+	 */
+	private function get_settings() {
+		if ( empty( self::$settings ) ) {
+			$post_types = $this->get_post_types();
+
+			$settings = get_option( $this->settings_section, array() );
+
+			$merged_settings = array();
+
+			foreach ( $post_types as $post_type => $name ) {
+				if ( array_key_exists( $post_type, $settings ) )
+					$merged_settings[ $post_type ] = (int) $settings[ $post_type ];
+				else
+					$merged_settings[ $post_type ] = -1;
+			}
+
+			self::$settings = $merged_settings;
+		}
+
+		return self::$settings;
+	}
+
+	/**
+	 * Retrieve array of supported post types and their labels
+	 *
+	 * @uses get_post_types
+	 * @uses post_type_supports
+	 * @uses get_post_type_object
+	 * @return array
+	 */
+	private function get_post_types() {
+		if ( empty( self::$post_types ) ) {
+			$types = get_post_types();
+
+			foreach ( $types as $type ) {
+				if ( post_type_supports( $type, 'revisions' ) ) {
+					$object = get_post_type_object( $type );
+
+					if ( property_exists( $object, 'labels' ) && property_exists( $object->labels, 'name' ) )
+						$name = $object->labels->name;
+					else
+						$name = $object->name;
+
+					self::$post_types[ $type ] = $name;
+				}
+			}
+		}
+
+		return self::$post_types;
+	}
+
+	/**
+	 * Retrieve number of revisions to keep for a given post type
+	 *
+	 * @uses WP_Post
+	 * @uses wp_revisions_to_keep
+	 * @return mixed
+	 */
+	private function get_revisions_to_keep( $post_type, $blank_for_all = false ) {
+		// wp_revisions_to_keep() accepts a post object, not just the post type
+		// We construct a new WP_Post object to ensure anything hooked to the wp_revisions_to_keep filter has the same basic data WP provides.
+		$_post = new WP_Post( (object) array( 'post_type' => $post_type ) );
+		$to_keep = wp_revisions_to_keep( $_post );
+
+		if ( $blank_for_all && -1 == $to_keep )
+			return '';
+		else
+			return (int) $to_keep;
+	}
+
+	/**
+	 * Retrieve number of revisions to keep for a give post
+	 *
+	 * @param int $post_id
+	 * @uses get_post_meta
+	 * @return mixed
+	 */
+	private function get_post_revisions_to_keep( $post_id ) {
+		$to_keep = get_post_meta( $post_id, $this->meta_key_limit, true );
+
+		if ( -1 == $to_keep || empty( $to_keep ) )
+			$to_keep = '';
+		else
+			$to_keep = (int) $to_keep;
+
+		return $to_keep;
+	}
+}
+WP_Revisions_Control::get_instance();