ClassLoader   F
last analyzed

Complexity

Total Complexity 64

Size/Duplication

Total Lines 391
Duplicated Lines 0 %

Importance

Changes 1
Bugs 0 Features 0
Metric Value
eloc 138
c 1
b 0
f 0
dl 0
loc 391
rs 3.28
wmc 64

21 Methods

Rating   Name   Duplication   Size   Complexity  
A register() 0 3 1
A getFallbackDirs() 0 3 1
A getUseIncludePath() 0 3 1
A getPrefixesPsr4() 0 3 1
A add() 0 33 5
A getClassMap() 0 3 1
A isClassMapAuthoritative() 0 3 1
A loadClass() 0 6 2
B addPsr4() 0 34 6
A setClassMapAuthoritative() 0 3 1
A addClassMap() 0 6 2
A unregister() 0 3 1
A set() 0 6 2
D findFileWithExtension() 0 64 18
A getFallbackDirsPsr4() 0 3 1
B findFile() 0 33 10
A getApcuPrefix() 0 3 1
A setPsr4() 0 11 3
A setApcuPrefix() 0 3 3
A setUseIncludePath() 0 3 1
A getPrefixes() 0 7 2

How to fix   Complexity   

Complex Class

Complex classes like ClassLoader often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.

Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.

While breaking up the class, it is a good idea to analyze how other classes use ClassLoader, and based on these observations, apply Extract Interface, too.

1
<?php
2
3
/*
4
 * This file is part of Composer.
5
 *
6
 * (c) Nils Adermann <[email protected]>
7
 *     Jordi Boggiano <[email protected]>
8
 *
9
 * For the full copyright and license information, please view the LICENSE
10
 * file that was distributed with this source code.
11
 */
12
13
namespace Composer\Autoload;
14
15
/**
16
 * ClassLoader implements a PSR-0, PSR-4 and classmap class loader.
17
 *
18
 *     $loader = new \Composer\Autoload\ClassLoader();
19
 *
20
 *     // register classes with namespaces
21
 *     $loader->add('Symfony\Component', __DIR__.'/component');
22
 *     $loader->add('Symfony',           __DIR__.'/framework');
23
 *
24
 *     // activate the autoloader
25
 *     $loader->register();
26
 *
27
 *     // to enable searching the include path (eg. for PEAR packages)
28
 *     $loader->setUseIncludePath(true);
29
 *
30
 * In this example, if you try to use a class in the Symfony\Component
31
 * namespace or one of its children (Symfony\Component\Console for instance),
32
 * the autoloader will first look for the class under the component/
33
 * directory, and it will then fallback to the framework/ directory if not
34
 * found before giving up.
35
 *
36
 * This class is loosely based on the Symfony UniversalClassLoader.
37
 *
38
 * @author Fabien Potencier <[email protected]>
39
 * @author Jordi Boggiano <[email protected]>
40
 * @see    https://www.php-fig.org/psr/psr-0/
41
 * @see    https://www.php-fig.org/psr/psr-4/
42
 */
43
class ClassLoader
44
{
45
    /** @var \Closure(string):void */
46
    private static $includeFile;
47
48
    /** @var ?string */
49
    private $vendorDir;
50
51
    // PSR-4
52
    /**
53
     * @var array[]
54
     * @psalm-var array<string, array<string, int>>
55
     */
56
    private $prefixLengthsPsr4 = array();
57
    /**
58
     * @var array[]
59
     * @psalm-var array<string, array<int, string>>
60
     */
61
    private $prefixDirsPsr4 = array();
62
    /**
63
     * @var array[]
64
     * @psalm-var array<string, string>
65
     */
66
    private $fallbackDirsPsr4 = array();
67
68
    // PSR-0
69
    /**
70
     * @var array[]
71
     * @psalm-var array<string, array<string, string[]>>
72
     */
73
    private $prefixesPsr0 = array();
74
    /**
75
     * @var array[]
76
     * @psalm-var array<string, string>
77
     */
78
    private $fallbackDirsPsr0 = array();
79
80
    /** @var bool */
81
    private $useIncludePath = false;
82
83
    /**
84
     * @var string[]
85
     * @psalm-var array<string, string>
86
     */
87
    private $classMap = array();
88
89
    /** @var bool */
90
    private $classMapAuthoritative = false;
91
92
    /**
93
     * @var bool[]
94
     * @psalm-var array<string, bool>
0 ignored issues
show
Bug Best Practice introduced by
The expression $this->classMap of type array is implicitly converted to a boolean; are you sure this is intended? If so, consider using ! empty($expr) instead to make it clear that you intend to check for an array without elements.

This check marks implicit conversions of arrays to boolean values in a comparison. While in PHP an empty array is considered to be equal (but not identical) to false, this is not always apparent.

Consider making the comparison explicit by using empty(..) or ! empty(...) instead.

Loading history...
95
     */
96
    private $missingClasses = array();
97
98
    /** @var ?string */
99
    private $apcuPrefix;
100
101
    /**
102
     * @var self[]
103
     */
104
    private static $registeredLoaders = array();
105
106
    /**
107
     * @param ?string $vendorDir
108
     */
109
    public function __construct($vendorDir = null)
110
    {
111
        $this->vendorDir = $vendorDir;
112
        self::initializeIncludeClosure();
113
    }
114
115
    /**
116
     * @return string[]
117
     */
118
    public function getPrefixes()
119
    {
120
        if (!empty($this->prefixesPsr0)) {
121
            return call_user_func_array('array_merge', array_values($this->prefixesPsr0));
122
        }
123
124
        return array();
125
    }
126
127
    /**
128
     * @return array[]
129
     * @psalm-return array<string, array<int, string>>
130
     */
131
    public function getPrefixesPsr4()
132
    {
133
        return $this->prefixDirsPsr4;
134
    }
135
136
    /**
137
     * @return array[]
138
     * @psalm-return array<string, string>
139
     */
140
    public function getFallbackDirs()
141
    {
142
        return $this->fallbackDirsPsr0;
143
    }
144
145
    /**
146
     * @return array[]
147
     * @psalm-return array<string, string>
148
     */
149
    public function getFallbackDirsPsr4()
150
    {
151
        return $this->fallbackDirsPsr4;
152
    }
153
154
    /**
155
     * @return string[] Array of classname => path
156
     * @psalm-return array<string, string>
157
     */
158
    public function getClassMap()
159
    {
160
        return $this->classMap;
161
    }
162
163
    /**
164
     * @param string[] $classMap Class to filename map
165
     * @psalm-param array<string, string> $classMap
166
     *
167
     * @return void
168
     */
169
    public function addClassMap(array $classMap)
170
    {
171
        if ($this->classMap) {
172
            $this->classMap = array_merge($this->classMap, $classMap);
173
        } else {
174
            $this->classMap = $classMap;
175
        }
176
    }
177
178
    /**
179
     * Registers a set of PSR-0 directories for a given prefix, either
180
     * appending or prepending to the ones previously set for this prefix.
181
     *
182
     * @param string          $prefix  The prefix
183
     * @param string[]|string $paths   The PSR-0 root directories
184
     * @param bool            $prepend Whether to prepend the directories
185
     *
186
     * @return void
187
     */
188
    public function add($prefix, $paths, $prepend = false)
189
    {
190
        if (!$prefix) {
191
            if ($prepend) {
192
                $this->fallbackDirsPsr0 = array_merge(
193
                    (array) $paths,
194
                    $this->fallbackDirsPsr0
195
                );
196
            } else {
197
                $this->fallbackDirsPsr0 = array_merge(
198
                    $this->fallbackDirsPsr0,
199
                    (array) $paths
200
                );
201
            }
202
203
            return;
204
        }
205
206
        $first = $prefix[0];
207
        if (!isset($this->prefixesPsr0[$first][$prefix])) {
208
            $this->prefixesPsr0[$first][$prefix] = (array) $paths;
209
210
            return;
211
        }
212
        if ($prepend) {
213
            $this->prefixesPsr0[$first][$prefix] = array_merge(
214
                (array) $paths,
215
                $this->prefixesPsr0[$first][$prefix]
216
            );
217
        } else {
218
            $this->prefixesPsr0[$first][$prefix] = array_merge(
219
                $this->prefixesPsr0[$first][$prefix],
220
                (array) $paths
221
            );
222
        }
223
    }
224
225
    /**
226
     * Registers a set of PSR-4 directories for a given namespace, either
227
     * appending or prepending to the ones previously set for this namespace.
228
     *
229
     * @param string          $prefix  The prefix/namespace, with trailing '\\'
230
     * @param string[]|string $paths   The PSR-4 base directories
231
     * @param bool            $prepend Whether to prepend the directories
232
     *
233
     * @throws \InvalidArgumentException
234
     *
235
     * @return void
236
     */
237
    public function addPsr4($prefix, $paths, $prepend = false)
238
    {
239
        if (!$prefix) {
240
            // Register directories for the root namespace.
241
            if ($prepend) {
242
                $this->fallbackDirsPsr4 = array_merge(
243
                    (array) $paths,
244
                    $this->fallbackDirsPsr4
245
                );
246
            } else {
247
                $this->fallbackDirsPsr4 = array_merge(
248
                    $this->fallbackDirsPsr4,
249
                    (array) $paths
250
                );
251
            }
252
        } elseif (!isset($this->prefixDirsPsr4[$prefix])) {
253
            // Register directories for a new namespace.
254
            $length = strlen($prefix);
255
            if ('\\' !== $prefix[$length - 1]) {
256
                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
257
            }
258
            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
259
            $this->prefixDirsPsr4[$prefix] = (array) $paths;
260
        } elseif ($prepend) {
261
            // Prepend directories for an already registered namespace.
262
            $this->prefixDirsPsr4[$prefix] = array_merge(
263
                (array) $paths,
264
                $this->prefixDirsPsr4[$prefix]
265
            );
266
        } else {
267
            // Append directories for an already registered namespace.
268
            $this->prefixDirsPsr4[$prefix] = array_merge(
269
                $this->prefixDirsPsr4[$prefix],
270
                (array) $paths
271
            );
272
        }
273
    }
274
275
    /**
276
     * Registers a set of PSR-0 directories for a given prefix,
277
     * replacing any others previously set for this prefix.
278
     *
279
     * @param string          $prefix The prefix
280
     * @param string[]|string $paths  The PSR-0 base directories
281
     *
282
     * @return void
283
     */
284
    public function set($prefix, $paths)
285
    {
286
        if (!$prefix) {
287
            $this->fallbackDirsPsr0 = (array) $paths;
288
        } else {
289
            $this->prefixesPsr0[$prefix[0]][$prefix] = (array) $paths;
290
        }
291
    }
292
293
    /**
294
     * Registers a set of PSR-4 directories for a given namespace,
295
     * replacing any others previously set for this namespace.
296
     *
297
     * @param string          $prefix The prefix/namespace, with trailing '\\'
298
     * @param string[]|string $paths  The PSR-4 base directories
299
     *
300
     * @throws \InvalidArgumentException
301
     *
302
     * @return void
303
     */
304
    public function setPsr4($prefix, $paths)
305
    {
306
        if (!$prefix) {
307
            $this->fallbackDirsPsr4 = (array) $paths;
308
        } else {
309
            $length = strlen($prefix);
310
            if ('\\' !== $prefix[$length - 1]) {
311
                throw new \InvalidArgumentException("A non-empty PSR-4 prefix must end with a namespace separator.");
312
            }
313
            $this->prefixLengthsPsr4[$prefix[0]][$prefix] = $length;
314
            $this->prefixDirsPsr4[$prefix] = (array) $paths;
315
        }
316
    }
317
318
    /**
319
     * Turns on searching the include path for class files.
320
     *
321
     * @param bool $useIncludePath
322
     *
323
     * @return void
324
     */
325
    public function setUseIncludePath($useIncludePath)
326
    {
327
        $this->useIncludePath = $useIncludePath;
328
    }
329
330
    /**
331
     * Can be used to check if the autoloader uses the include path to check
332
     * for classes.
333
     *
334
     * @return bool
335
     */
336
    public function getUseIncludePath()
337
    {
338
        return $this->useIncludePath;
339
    }
340
341
    /**
342
     * Turns off searching the prefix and fallback directories for classes
343
     * that have not been registered with the class map.
344
     *
345
     * @param bool $classMapAuthoritative
346
     *
347
     * @return void
348
     */
349
    public function setClassMapAuthoritative($classMapAuthoritative)
350
    {
351
        $this->classMapAuthoritative = $classMapAuthoritative;
352
    }
353
354
    /**
355
     * Should class lookup fail if not found in the current class map?
356
     *
357
     * @return bool
358
     */
359
    public function isClassMapAuthoritative()
360
    {
361
        return $this->classMapAuthoritative;
362
    }
363
364
    /**
365
     * APCu prefix to use to cache found/not-found classes, if the extension is enabled.
366
     *
367
     * @param string|null $apcuPrefix
368
     *
369
     * @return void
370
     */
371
    public function setApcuPrefix($apcuPrefix)
372
    {
373
        $this->apcuPrefix = function_exists('apcu_fetch') && filter_var(ini_get('apc.enabled'), FILTER_VALIDATE_BOOLEAN) ? $apcuPrefix : null;
374
    }
375
376
    /**
377
     * The APCu prefix in use, or null if APCu caching is not enabled.
378
     *
379
     * @return string|null
380
     */
381
    public function getApcuPrefix()
382
    {
383
        return $this->apcuPrefix;
384
    }
385
386
    /**
387
     * Registers this instance as an autoloader.
388
     *
389
     * @param bool $prepend Whether to prepend the autoloader or not
390
     *
391
     * @return void
392
     */
393
    public function register($prepend = false)
394
    {
395
        spl_autoload_register(array($this, 'loadClass'), true, $prepend);
396
397
        if (null === $this->vendorDir) {
398
            return;
399
        }
400
401
        if ($prepend) {
402
            self::$registeredLoaders = array($this->vendorDir => $this) + self::$registeredLoaders;
403
        } else {
404
            unset(self::$registeredLoaders[$this->vendorDir]);
405
            self::$registeredLoaders[$this->vendorDir] = $this;
406
        }
407
    }
408
409
    /**
410
     * Unregisters this instance as an autoloader.
411
     *
412
     * @return void
413
     */
414
    public function unregister()
415
    {
416
        spl_autoload_unregister(array($this, 'loadClass'));
417
418
        if (null !== $this->vendorDir) {
419
            unset(self::$registeredLoaders[$this->vendorDir]);
420
        }
421
    }
422
423
    /**
424
     * Loads the given class or interface.
425
     *
426
     * @param  string    $class The name of the class
427
     * @return true|null True if loaded, null otherwise
428
     */
429
    public function loadClass($class)
430
    {
431
        if ($file = $this->findFile($class)) {
432
            (self::$includeFile)($file);
433
434
            return true;
435
        }
436
437
        return null;
438
    }
439
440
    /**
441
     * Finds the path to the file where the class is defined.
442
     *
443
     * @param string $class The name of the class
444
     *
445
     * @return string|false The path if found, false otherwise
446
     */
447
    public function findFile($class)
448
    {
449
        // class map lookup
450
        if (isset($this->classMap[$class])) {
451
            return $this->classMap[$class];
452
        }
453
        if ($this->classMapAuthoritative || isset($this->missingClasses[$class])) {
454
            return false;
455
        }
456
        if (null !== $this->apcuPrefix) {
457
            $file = apcu_fetch($this->apcuPrefix.$class, $hit);
458
            if ($hit) {
459
                return $file;
460
            }
461
        }
462
463
        $file = $this->findFileWithExtension($class, '.php');
464
465
        // Search for Hack files if we are running on HHVM
466
        if (false === $file && defined('HHVM_VERSION')) {
467
            $file = $this->findFileWithExtension($class, '.hh');
468
        }
469
470
        if (null !== $this->apcuPrefix) {
471
            apcu_add($this->apcuPrefix.$class, $file);
472
        }
473
474
        if (false === $file) {
475
            // Remember that this class does not exist.
476
            $this->missingClasses[$class] = true;
477
        }
478
479
        return $file;
480
    }
481
482
    /**
483
     * Returns the currently registered loaders indexed by their corresponding vendor directories.
484
     *
485
     * @return self[]
486
     */
487
    public static function getRegisteredLoaders()
488
    {
489
        return self::$registeredLoaders;
490
    }
491
492
    /**
493
     * @param  string       $class
494
     * @param  string       $ext
495
     * @return string|false
496
     */
497
    private function findFileWithExtension($class, $ext)
498
    {
499
        // PSR-4 lookup
500
        $logicalPathPsr4 = strtr($class, '\\', DIRECTORY_SEPARATOR) . $ext;
501
502
        $first = $class[0];
503
        if (isset($this->prefixLengthsPsr4[$first])) {
504
            $subPath = $class;
505
            while (false !== $lastPos = strrpos($subPath, '\\')) {
506
                $subPath = substr($subPath, 0, $lastPos);
507
                $search = $subPath . '\\';
508
                if (isset($this->prefixDirsPsr4[$search])) {
509
                    $pathEnd = DIRECTORY_SEPARATOR . substr($logicalPathPsr4, $lastPos + 1);
510
                    foreach ($this->prefixDirsPsr4[$search] as $dir) {
511
                        if (file_exists($file = $dir . $pathEnd)) {
512
                            return $file;
513
                        }
514
                    }
515
                }
516
            }
517
        }
518
519
        // PSR-4 fallback dirs
520
        foreach ($this->fallbackDirsPsr4 as $dir) {
521
            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr4)) {
522
                return $file;
523
            }
524
        }
525
526
        // PSR-0 lookup
527
        if (false !== $pos = strrpos($class, '\\')) {
528
            // namespaced class name
529
            $logicalPathPsr0 = substr($logicalPathPsr4, 0, $pos + 1)
530
                . strtr(substr($logicalPathPsr4, $pos + 1), '_', DIRECTORY_SEPARATOR);
531
        } else {
532
            // PEAR-like class name
533
            $logicalPathPsr0 = strtr($class, '_', DIRECTORY_SEPARATOR) . $ext;
534
        }
535
536
        if (isset($this->prefixesPsr0[$first])) {
537
            foreach ($this->prefixesPsr0[$first] as $prefix => $dirs) {
538
                if (0 === strpos($class, $prefix)) {
539
                    foreach ($dirs as $dir) {
540
                        if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
541
                            return $file;
542
                        }
543
                    }
544
                }
545
            }
546
        }
547
548
        // PSR-0 fallback dirs
549
        foreach ($this->fallbackDirsPsr0 as $dir) {
550
            if (file_exists($file = $dir . DIRECTORY_SEPARATOR . $logicalPathPsr0)) {
551
                return $file;
552
            }
553
        }
554
555
        // PSR-0 include paths.
556
        if ($this->useIncludePath && $file = stream_resolve_include_path($logicalPathPsr0)) {
557
            return $file;
558
        }
559
560
        return false;
561
    }
562
563
    private static function initializeIncludeClosure(): void
564
    {
565
        if (self::$includeFile !== null) {
566
            return;
567
        }
568
569
        /**
570
         * Scope isolated include.
571
         *
572
         * Prevents access to $this/self from included files.
573
         *
574
         * @param  string $file
575
         * @return void
576
         */
577
        self::$includeFile = static function($file) {
578
            include $file;
579
        };
580
    }
581
}
582