Composer\Autoload

ClassLoader{}WPSCache 1.0

ClassLoader implements a PSR-0, PSR-4 and classmap class loader.

$loader = new \Composer\Autoload[ClassLoader()](/plugin/wp-super-cache/function/ClassLoader);

// register classes with namespaces
$loader->add('Symfony\Component', __DIR__.'/component');
$loader->add('Symfony',           __DIR__.'/framework');
// activate the autoloader
$loader->register();
// to enable searching the include path (eg. for PEAR packages)
$loader->setUseIncludePath(true);

In this example, if you try to use a class in the Symfony\Component namespace or one of its children (Symfony\Component\Console for instance), the autoloader will first look for the class under the component/ directory, and it will then fallback to the framework/ directory if not found before giving up.

This class is loosely based on the Symfony UniversalClassLoader.

Хуков нет.

Использование

$ClassLoader = new ClassLoader();
// use class methods

Методы

  1. public __construct($vendorDir = null)
  2. public add($prefix, $paths, $prepend = false)
  3. public addClassMap(array $classMap)
  4. public addPsr4($prefix, $paths, $prepend = false)
  5. public findFile($class)
  6. private findFileWithExtension($class, $ext)
  7. public getApcuPrefix()
  8. public getClassMap()
  9. public getFallbackDirs()
  10. public getFallbackDirsPsr4()
  11. public getPrefixes()
  12. public getPrefixesPsr4()
  13. public static getRegisteredLoaders()
  14. public getUseIncludePath()
  15. private static initializeIncludeClosure()
  16. public isClassMapAuthoritative()
  17. public loadClass($class)
  18. public register($prepend = false)
  19. public set($prefix, $paths)
  20. public setApcuPrefix($apcuPrefix)
  21. public setClassMapAuthoritative($classMapAuthoritative)
  22. public setPsr4($prefix, $paths)
  23. public setUseIncludePath($useIncludePath)
  24. public unregister()

Заметки

Код ClassLoader{} WPSCache 1.12.4

class ClassLoader
{
    /** @var \Closure(string):void */
    private static $includeFile;

    /** @var string|null */
    private $vendorDir;

    // PSR-4
    /**
     * @var array<string, array<string, int>>
     */
    private $prefixLengthsPsr4 = array();
    /**
     * @var array<string, list<string>>
     */
    private $prefixDirsPsr4 = array();
    /**
     * @var list<string>
     */
    private $fallbackDirsPsr4 = array();

    // PSR-0
    /**
     * List of PSR-0 prefixes
     *
     * Structured as array('F (first letter)' => array('Foo\Bar (full prefix)' => array('path', 'path2')))
     *
     * @var array<string, array<string, list<string>>>
     */
    private $prefixesPsr0 = array();
    /**
     * @var list<string>
     */
    private $fallbackDirsPsr0 = array();

    /** @var bool */
    private $useIncludePath = false;

    /**
     * @var array<string, string>
     */
    private $classMap = array();

    /** @var bool */
    private $classMapAuthoritative = false;

    /**
     * @var array<string, bool>
     */
    private $missingClasses = array();

    /** @var string|null */
    private $apcuPrefix;

    /**
     * @var array<string, self>
     */
    private static $registeredLoaders = array();

    /**
     * @param string|null $vendorDir
     */
    public function __construct($vendorDir = null)
    {
        $this->vendorDir = $vendorDir;
        self::initializeIncludeClosure();
    }

    /**
     * @return array<string, list<string>>
     */
    public function getPrefixes()
    {
        if (!empty($this->prefixesPsr0)) {
            return call_user_func_array('array_merge', array_values($this->prefixesPsr0));
        }

        return array();
    }

    /**
     * @return array<string, list<string>>
     */
    public function getPrefixesPsr4()
    {
        return $this->prefixDirsPsr4;
    }

    /**
     * @return list<string>
     */
    public function getFallbackDirs()
    {
        return $this->fallbackDirsPsr0;
    }

    /**
     * @return list<string>
     */
    public function getFallbackDirsPsr4()
    {
        return $this->fallbackDirsPsr4;
    }

    /**
     * @return array<string, string> Array of classname => path
     */
    public function getClassMap()
    {
        return $this->classMap;
    }

    /**
     * @param array<string, string> $classMap Class to filename map
     *
     * @return void
     */
    public function addClassMap(array $classMap)
    {
        if ($this->classMap) {
            $this->classMap = array_merge($this->classMap, $classMap);
        } else {
            $this->classMap = $classMap;
        }
    }

    /**
     * Registers a set of PSR-0 directories for a given prefix, either
     * appending or prepending to the ones previously set for this prefix.
     *
     * @param string              $prefix  The prefix
     * @param list<string>|string $paths   The PSR-0 root directories
     * @param bool                $prepend Whether to prepend the directories
     *
     * @return void
     */
    public function add($prefix, $paths, $prepend = false)
    {
        $paths = (array) $paths;
        if (!$prefix) {
            if ($prepend) {
                $this->fallbackDirsPsr0 = array_merge(
                    $paths,
                    $this->fallbackDirsPsr0
                );
            } else {
                $this->fallbackDirsPsr0 = array_merge(
                    $this->fallbackDirsPsr0,
                    $paths
                );
            }

            return;
        }

        $first = $prefix[0];
        if (!isset($this->prefixesPsr0[$first][$prefix])) {
            $this->prefixesPsr0[$first][$prefix] = $paths;

            return;
        }
        if ($prepend) {
            $this->prefixesPsr0[$first][$prefix] = array_merge(
                $paths,
                $this->prefixesPsr0[$first][$prefix]
            );
        } else {
            $this->prefixesPsr0[$first][$prefix] = array_merge(
                $this->prefixesPsr0[$first][$prefix],
                $paths
            );
        }
    }

    /**
     * Registers a set of PSR-4 directories for a given namespace, either
     * appending or prepending to the ones previously set for this namespace.
     *
     * @param string              $prefix  The prefix/namespace, with trailing '\\'
     * @param list<string>|string $paths   The PSR-4 base directories
     * @param bool                $prepend Whether to prepend the directories
     *
     * @throws \InvalidArgumentException
     *
     * @return void
     */
    public function addPsr4($prefix, $paths, $prepend = false)
    {
        $paths = (array) $paths;
        if (!$prefix) {
            // Register directories for the root namespace.
            if ($prepend) {
                $this->fallbackDirsPsr4 = array_merge(
                    $paths,
                    $this->fallbackDirsPsr4
                );
            } else {
                $this->fallbackDirsPsr4 = array_merge(
                    $this->fallbackDirsPsr4,
                    $paths
                );
            }
        } elseif (!isset($this->prefixDirsPsr4[$prefix])) {
            // Register directories for a new namespace.
            $length = strlen($prefix);
            if ('\\' !== $prefix[$length - 1]) {
                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
            }
            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
            $this->prefixDirsPsr4[$prefix] = $paths;
        } elseif ($prepend) {
            // Prepend directories for an already registered namespace.
            $this->prefixDirsPsr4[$prefix] = array_merge(
                $paths,
                $this->prefixDirsPsr4[$prefix]
            );
        } else {
            // Append directories for an already registered namespace.
            $this->prefixDirsPsr4[$prefix] = array_merge(
                $this->prefixDirsPsr4[$prefix],
                $paths
            );
        }
    }

    /**
     * Registers a set of PSR-0 directories for a given prefix,
     * replacing any others previously set for this prefix.
     *
     * @param string              $prefix The prefix
     * @param list<string>|string $paths  The PSR-0 base directories
     *
     * @return void
     */
    public function set($prefix, $paths)
    {
        if (!$prefix) {
            $this->fallbackDirsPsr0 = (array) $paths;
        } else {
            $this->prefixesPsr0[$prefix[0]][$prefix] = (array) $paths;
        }
    }

    /**
     * Registers a set of PSR-4 directories for a given namespace,
     * replacing any others previously set for this namespace.
     *
     * @param string              $prefix The prefix/namespace, with trailing '\\'
     * @param list<string>|string $paths  The PSR-4 base directories
     *
     * @throws \InvalidArgumentException
     *
     * @return void
     */
    public function setPsr4($prefix, $paths)
    {
        if (!$prefix) {
            $this->fallbackDirsPsr4 = (array) $paths;
        } else {
            $length = strlen($prefix);
            if ('\\' !== $prefix[$length - 1]) {
                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
            }
            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
            $this->prefixDirsPsr4[$prefix] = (array) $paths;
        }
    }

    /**
     * Turns on searching the include path for class files.
     *
     * @param bool $useIncludePath
     *
     * @return void
     */
    public function setUseIncludePath($useIncludePath)
    {
        $this->useIncludePath = $useIncludePath;
    }

    /**
     * Can be used to check if the autoloader uses the include path to check
     * for classes.
     *
     * @return bool
     */
    public function getUseIncludePath()
    {
        return $this->useIncludePath;
    }

    /**
     * Turns off searching the prefix and fallback directories for classes
     * that have not been registered with the class map.
     *
     * @param bool $classMapAuthoritative
     *
     * @return void
     */
    public function setClassMapAuthoritative($classMapAuthoritative)
    {
        $this->classMapAuthoritative = $classMapAuthoritative;
    }

    /**
     * Should class lookup fail if not found in the current class map?
     *
     * @return bool
     */
    public function isClassMapAuthoritative()
    {
        return $this->classMapAuthoritative;
    }

    /**
     * APCu prefix to use to cache found/not-found classes, if the extension is enabled.
     *
     * @param string|null $apcuPrefix
     *
     * @return void
     */
    public function setApcuPrefix($apcuPrefix)
    {
        $this->apcuPrefix = function_exists('apcu_fetch') && filter_var(ini_get('apc.enabled'), FILTER_VALIDATE_BOOLEAN) ? $apcuPrefix : null;
    }

    /**
     * The APCu prefix in use, or null if APCu caching is not enabled.
     *
     * @return string|null
     */
    public function getApcuPrefix()
    {
        return $this->apcuPrefix;
    }

    /**
     * Registers this instance as an autoloader.
     *
     * @param bool $prepend Whether to prepend the autoloader or not
     *
     * @return void
     */
    public function register($prepend = false)
    {
        spl_autoload_register(array($this, 'loadClass'), true, $prepend);

        if (null === $this->vendorDir) {
            return;
        }

        if ($prepend) {
            self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
        } else {
            unset(self::$registeredLoaders[$this->vendorDir]);
            self::$registeredLoaders[$this->vendorDir] = $this;
        }
    }

    /**
     * Unregisters this instance as an autoloader.
     *
     * @return void
     */
    public function unregister()
    {
        spl_autoload_unregister(array($this, 'loadClass'));

        if (null !== $this->vendorDir) {
            unset(self::$registeredLoaders[$this->vendorDir]);
        }
    }

    /**
     * Loads the given class or interface.
     *
     * @param  string    $class The name of the class
     * @return true|null True if loaded, null otherwise
     */
    public function loadClass($class)
    {
        if ($file = $this->findFile($class)) {
            $includeFile = self::$includeFile;
            $includeFile($file);

            return true;
        }

        return null;
    }

    /**
     * Finds the path to the file where the class is defined.
     *
     * @param string $class The name of the class
     *
     * @return string|false The path if found, false otherwise
     */
    public function findFile($class)
    {
        // class map lookup
        if (isset($this->classMap[$class])) {
            return $this->classMap[$class];
        }
        if ($this->classMapAuthoritative || isset($this->missingClasses[$class])) {
            return false;
        }
        if (null !== $this->apcuPrefix) {
            $file = apcu_fetch($this->apcuPrefix.$class, $hit);
            if ($hit) {
                return $file;
            }
        }

        $file = $this->findFileWithExtension($class, '.php');

        // Search for Hack files if we are running on HHVM
        if (false === $file && defined('HHVM_VERSION')) {
            $file = $this->findFileWithExtension($class, '.hh');
        }

        if (null !== $this->apcuPrefix) {
            apcu_add($this->apcuPrefix.$class, $file);
        }

        if (false === $file) {
            // Remember that this class does not exist.
            $this->missingClasses[$class] = true;
        }

        return $file;
    }

    /**
     * Returns the currently registered loaders keyed by their corresponding vendor directories.
     *
     * @return array<string, self>
     */
    public static function getRegisteredLoaders()
    {
        return self::$registeredLoaders;
    }

    /**
     * @param  string       $class
     * @param  string       $ext
     * @return string|false
     */
    private function findFileWithExtension($class, $ext)
    {
        // PSR-4 lookup
        $logicalPathPsr4 = strtr($class, '\\', DIRECTORY_SEPARATOR) . $ext;

        $first = $class[0];
        if (isset($this->prefixLengthsPsr4[$first])) {
            $subPath = $class;
            while (false !== $lastPos = strrpos($subPath, '\\')) {
                $subPath = substr($subPath, 0, $lastPos);
                $search = $subPath . '\\';
                if (isset($this->prefixDirsPsr4[$search])) {
                    $pathEnd = DIRECTORY_SEPARATOR . substr($logicalPathPsr4, $lastPos + 1);
                    foreach ($this->prefixDirsPsr4[$search] as $dir) {
                        if (file_exists($file = $dir . $pathEnd)) {
                            return $file;
                        }
                    }
                }
            }
        }

        // PSR-4 fallback dirs
        foreach ($this->fallbackDirsPsr4 as $dir) {
            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr4)) {
                return $file;
            }
        }

        // PSR-0 lookup
        if (false !== $pos = strrpos($class, '\\')) {
            // namespaced class name
            $logicalPathPsr0 = substr($logicalPathPsr4, 0, $pos + 1)
                . strtr(substr($logicalPathPsr4, $pos + 1), '_', DIRECTORY_SEPARATOR);
        } else {
            // PEAR-like class name
            $logicalPathPsr0 = strtr($class, '_', DIRECTORY_SEPARATOR) . $ext;
        }

        if (isset($this->prefixesPsr0[$first])) {
            foreach ($this->prefixesPsr0[$first] as $prefix => $dirs) {
                if (0 === strpos($class, $prefix)) {
                    foreach ($dirs as $dir) {
                        if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
                            return $file;
                        }
                    }
                }
            }
        }

        // PSR-0 fallback dirs
        foreach ($this->fallbackDirsPsr0 as $dir) {
            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
                return $file;
            }
        }

        // PSR-0 include paths.
        if ($this->useIncludePath && $file = stream_resolve_include_path($logicalPathPsr0)) {
            return $file;
        }

        return false;
    }

    /**
     * @return void
     */
    private static function initializeIncludeClosure()
    {
        if (self::$includeFile !== null) {
            return;
        }

        /**
         * Scope isolated include.
         *
         * Prevents access to $this/self from included files.
         *
         * @param  string $file
         * @return void
         */
        self::$includeFile = \Closure::bind(static function($file) {
            include $file;
        }, null, null);
    }
}