Tests for autoload.php

.gitignore

@@ -5,3 +5,4 @@ composer.lock
 phpunit.xml
 .php-cs-fixer.php
 clover.xml
+src/AutoloadStub.php

autoloader.php

@@ -6,7 +6,7 @@ declare(strict_types=1);
  *
  * To use this just include this file in your script and the JsonMachine namespace will be made available
  *
- * i.e. require_once('/path/to/json-machine/Autoloader.php');
+ * Usage: spl_autoload_register(require_once('/path/to/Autoloader.php'));
  *
  * See: https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-4-autoloader-examples.md
  *
@@ -14,7 +14,8 @@ declare(strict_types=1);
  *
  * @return void
  */
-spl_autoload_register(function ($class) {
+
+return function ($class) {
     // project-specific namespace prefix
     $prefix = 'JsonMachine\\';
 
@@ -40,4 +41,4 @@ spl_autoload_register(function ($class) {
     if (file_exists($file)) {
         require $file;
     }
-});
+};

test/JsonMachineTest/autoloaderTest.php

@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+namespace JsonMachineTest;
+
+/**
+ * @covers \JsonMachine\FileChunks
+ */
+class autoloaderTest extends \PHPUnit_Framework_TestCase
+{
+    public function testAutoloaderLoadsClass()
+    {
+        $dummyFile = $this->createAutoloadableClass();
+
+        $autoloadersBackup = $this->unregisterCurrentAutoloaders();
+        $autoloader = require __DIR__.'/../../autoloader.php';
+
+        spl_autoload_register($autoloader);
+        $autoloaded = class_exists('JsonMachine\\AutoloadStub');
+        spl_autoload_unregister($autoloader);
+
+        $this->registerPreviousAutoloaders($autoloadersBackup);
+
+        $this->assertTrue($autoloaded);
+
+        @unlink($dummyFile);
+    }
+
+    private function createAutoloadableClass(): string
+    {
+        $dummyFile = __DIR__.'/../../src/AutoloadStub.php';
+        file_put_contents($dummyFile, '<?php namespace JsonMachine; class AutoloadStub {}');
+
+        return $dummyFile;
+    }
+
+    private function unregisterCurrentAutoloaders(): array
+    {
+        $autoloadersBackup = [];
+        foreach (spl_autoload_functions() as $autoloader) {
+            $autoloadersBackup[] = $autoloader;
+            spl_autoload_unregister($autoloader);
+        }
+
+        return $autoloadersBackup;
+    }
+
+    private function registerPreviousAutoloaders(array $autoloadersBackup)
+    {
+        foreach ($autoloadersBackup as $restoreAutoloader) {
+            spl_autoload_register($restoreAutoloader);
+        }
+    }
+}