Extract file parsing and lookup as a separate "Package" class.

Puc/v4p4/InstalledPackage.php

@@ -0,0 +1,103 @@
+<?php
+if ( !class_exists('Puc_v4p4_InstalledPackage', false) ):
+
+	/**
+	 * This class represents a currently installed plugin or theme.
+	 *
+	 * Not to be confused with the "package" field in WP update API responses that contains
+	 * the download URL of a the new version.
+	 */
+	abstract class Puc_v4p4_InstalledPackage {
+		/**
+		 * @var Puc_v4p4_UpdateChecker
+		 */
+		protected $updateChecker;
+
+		public function __construct($updateChecker) {
+			$this->updateChecker = $updateChecker;
+		}
+
+		/**
+		 * Get the currently installed version of the plugin or theme.
+		 *
+		 * @return string|null Version number.
+		 */
+		abstract public function getInstalledVersion();
+
+		/**
+		 * Get the full path of the plugin or theme directory (without a trailing slash).
+		 *
+		 * @return string
+		 */
+		abstract public function getAbsoluteDirectoryPath();
+
+		/**
+		 * Check whether a regular file exists in the package's directory.
+		 *
+		 * @param string $relativeFileName File name relative to the package directory.
+		 * @return bool
+		 */
+		public function fileExists($relativeFileName) {
+			return is_file(
+				$this->getAbsoluteDirectoryPath()
+				. DIRECTORY_SEPARATOR
+				. ltrim($relativeFileName, '/\\')
+			);
+		}
+
+		/* -------------------------------------------------------------------
+		 * File header parsing
+		 * -------------------------------------------------------------------
+		 */
+
+		/**
+		 * Parse plugin or theme metadata from the header comment.
+		 *
+		 * This is basically a simplified version of the get_file_data() function from /wp-includes/functions.php.
+		 * It's intended as a utility for subclasses that detect updates by parsing files in a VCS.
+		 *
+		 * @param string|null $content File contents.
+		 * @return string[]
+		 */
+		public function getFileHeader($content) {
+			$content = (string)$content;
+
+			//WordPress only looks at the first 8 KiB of the file, so we do the same.
+			$content = substr($content, 0, 8192);
+			//Normalize line endings.
+			$content = str_replace("\r", "\n", $content);
+
+			$headers = $this->getHeaderNames();
+			$results = array();
+			foreach ($headers as $field => $name) {
+				$success = preg_match('/^[ \t\/*#@]*' . preg_quote($name, '/') . ':(.*)$/mi', $content, $matches);
+
+				if ( ($success === 1) && $matches[1] ) {
+					$value = $matches[1];
+					if ( function_exists('_cleanup_header_comment') ) {
+						$value = _cleanup_header_comment($value);
+					}
+					$results[$field] = $value;
+				} else {
+					$results[$field] = '';
+				}
+			}
+
+			return $results;
+		}
+
+		/**
+		 * @return array Format: ['HeaderKey' => 'Header Name']
+		 */
+		abstract protected function getHeaderNames();
+
+		/**
+		 * Get the value of a specific plugin or theme header.
+		 *
+		 * @param string $headerName
+		 * @return string Either the value of the header, or an empty string if the header doesn't exist.
+		 */
+		abstract public function getHeaderValue($headerName);
+
+	}
+endif;

Puc/v4p4/Plugin/Package.php

@@ -0,0 +1,174 @@
+<?php
+if ( !class_exists('Puc_v4p4_Plugin_Package', false) ):
+
+	class Puc_v4p4_Plugin_Package extends Puc_v4p4_InstalledPackage {
+		/**
+		 * @var Puc_v4p4_Plugin_UpdateChecker
+		 */
+		protected $updateChecker;
+
+		/**
+		 * @var string Full path of the main plugin file.
+		 */
+		protected $pluginAbsolutePath = '';
+
+		/**
+		 * @var string Plugin basename.
+		 */
+		private $pluginFile;
+
+		/**
+		 * @var string|null
+		 */
+		private $cachedInstalledVersion = null;
+
+		public function __construct($pluginAbsolutePath, $updateChecker) {
+			$this->pluginAbsolutePath = $pluginAbsolutePath;
+			$this->pluginFile = plugin_basename($this->pluginAbsolutePath);
+
+			parent::__construct($updateChecker);
+
+			//Clear the version number cache when something - anything - is upgraded or WP clears the update cache.
+			add_filter('upgrader_post_install', array($this, 'clearCachedVersion'));
+			add_action('delete_site_transient_update_plugins', array($this, 'clearCachedVersion'));
+		}
+
+		public function getInstalledVersion() {
+			if ( isset($this->cachedInstalledVersion) ) {
+				return $this->cachedInstalledVersion;
+			}
+
+			$pluginHeader = $this->getPluginHeader();
+			if ( isset($pluginHeader['Version']) ) {
+				$this->cachedInstalledVersion = $pluginHeader['Version'];
+				return $pluginHeader['Version'];
+			} else {
+				//This can happen if the filename points to something that is not a plugin.
+				$this->updateChecker->triggerError(
+					sprintf(
+						"Can't to read the Version header for '%s'. The filename is incorrect or is not a plugin.",
+						$this->updateChecker->pluginFile
+					),
+					E_USER_WARNING
+				);
+				return null;
+			}
+		}
+
+		/**
+		 * Clear the cached plugin version. This method can be set up as a filter (hook) and will
+		 * return the filter argument unmodified.
+		 *
+		 * @param mixed $filterArgument
+		 * @return mixed
+		 */
+		public function clearCachedVersion($filterArgument = null) {
+			$this->cachedInstalledVersion = null;
+			return $filterArgument;
+		}
+
+		public function getAbsoluteDirectoryPath() {
+			return dirname($this->pluginAbsolutePath);
+		}
+
+		/**
+		 * Get the value of a specific plugin or theme header.
+		 *
+		 * @param string $headerName
+		 * @param string $defaultValue
+		 * @return string Either the value of the header, or $defaultValue if the header doesn't exist or is empty.
+		 */
+		public function getHeaderValue($headerName, $defaultValue = '') {
+			$headers = $this->getPluginHeader();
+			if ( isset($headers[$headerName]) && ($headers[$headerName] !== '') ) {
+				return $headers[$headerName];
+			}
+			return $defaultValue;
+		}
+
+		protected function getHeaderNames() {
+			return array(
+				'Name'              => 'Plugin Name',
+				'PluginURI'         => 'Plugin URI',
+				'Version'           => 'Version',
+				'Description'       => 'Description',
+				'Author'            => 'Author',
+				'AuthorURI'         => 'Author URI',
+				'TextDomain'        => 'Text Domain',
+				'DomainPath'        => 'Domain Path',
+				'Network'           => 'Network',
+
+				//The newest WordPress version that this plugin requires or has been tested with.
+				//We support several different formats for compatibility with other libraries.
+				'Tested WP'         => 'Tested WP',
+				'Requires WP'       => 'Requires WP',
+				'Tested up to'      => 'Tested up to',
+				'Requires at least' => 'Requires at least',
+			);
+		}
+
+		/**
+		 * Get the translated plugin title.
+		 *
+		 * @return string
+		 */
+		public function getPluginTitle() {
+			$title = '';
+			$header = $this->getPluginHeader();
+			if ( $header && !empty($header['Name']) && isset($header['TextDomain']) ) {
+				$title = translate($header['Name'], $header['TextDomain']);
+			}
+			return $title;
+		}
+
+		/**
+		 * Get plugin's metadata from its file header.
+		 *
+		 * @return array
+		 */
+		public function getPluginHeader() {
+			if ( !is_file($this->pluginAbsolutePath) ) {
+				//This can happen if the plugin filename is wrong.
+				$this->updateChecker->triggerError(
+					sprintf(
+						"Can't to read the plugin header for '%s'. The file does not exist.",
+						$this->updateChecker->pluginFile
+					),
+					E_USER_WARNING
+				);
+				return array();
+			}
+
+			if ( !function_exists('get_plugin_data') ) {
+				/** @noinspection PhpIncludeInspection */
+				require_once(ABSPATH . '/wp-admin/includes/plugin.php');
+			}
+			return get_plugin_data($this->pluginAbsolutePath, false, false);
+		}
+
+		public function removeHooks() {
+			remove_filter('upgrader_post_install', array($this, 'clearCachedVersion'));
+			remove_action('delete_site_transient_update_plugins', array($this, 'clearCachedVersion'));
+		}
+
+		/**
+		 * Check if the plugin file is inside the mu-plugins directory.
+		 *
+		 * @return bool
+		 */
+		public function isMuPlugin() {
+			static $cachedResult = null;
+
+			if ( $cachedResult === null ) {
+				//Convert both paths to the canonical form before comparison.
+				$muPluginDir = realpath(WPMU_PLUGIN_DIR);
+				$pluginPath  = realpath($this->pluginAbsolutePath);
+
+				$cachedResult = (strpos($pluginPath, $muPluginDir) === 0);
+			}
+
+			return $cachedResult;
+		}
+	}
+
+endif;

Puc/v4p4/Plugin/Ui.php

@@ -198,7 +198,7 @@ public function handleManualCheck() {
 		public function displayManualCheckResult() {
 			if ( isset($_GET['puc_update_check_result'], $_GET['puc_slug']) && ($_GET['puc_slug'] == $this->updateChecker->slug) ) {
 				$status = strval($_GET['puc_update_check_result']);
-				$title = $this->updateChecker->getPluginTitle();
+				$title = $this->updateChecker->getInstalledPackage()->getPluginTitle();
 				$noticeClass = 'updated notice-success';
 				$details = '';