class PhpStorageTestBase

abstract class PhpStorageTestBase extends TestCase {
    
    /**
     * A unique per test class directory path to test php storage.
     *
     * @var string
     */
    protected $directory;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() {
        parent::setUp();
        vfsStream::setup('exampleDir');
        $this->directory = vfsStream::url('exampleDir');
    }
    
    /**
     * Assert that a PHP storage's load/save/delete operations work.
     */
    public function assertCRUD($php) {
        // Random generator.
        $random_generator = new Random();
        $name = $random_generator->name(8, TRUE) . '/' . $random_generator->name(8, TRUE) . '.php';
        // Find a global that doesn't exist.
        do {
            $random = 'test' . mt_rand(10000, 100000);
        } while (isset($GLOBALS[$random]));
        // Write out a PHP file and ensure it's successfully loaded.
        $code = "<?php\n\$GLOBALS['{$random}'] = TRUE;";
        $success = $php->save($name, $code);
        $this->assertTrue($success, 'Saved php file');
        $php->load($name);
        $this->assertTrue($GLOBALS[$random], 'File saved correctly with correct value');
        // Run additional asserts.
        $this->additionalAssertCRUD($php, $name);
        // If the file was successfully loaded, it must also exist, but ensure the
        // exists() method returns that correctly.
        $this->assertTrue($php->exists($name), 'Exists works correctly');
        // Delete the file, and then ensure exists() returns FALSE.
        $this->assertTrue($php->delete($name), 'Delete succeeded');
        $this->assertFalse($php->exists($name), 'Delete deleted file');
        // Ensure delete() can be called on a non-existing file. It should return
        // FALSE, but not trigger errors.
        $this->assertFalse($php->delete($name), 'Delete fails on missing file');
        unset($GLOBALS[$random]);
    }
    
    /**
     * Additional asserts to be run.
     *
     * @param \Drupal\Component\PhpStorage\PhpStorageInterface $php
     *   The PHP storage object.
     * @param string $name
     *   The name of an object. It should exist in the storage.
     */
    protected function additionalAssertCRUD(PhpStorageInterface $php, $name) {
        // By default do not do any additional asserts. This is a way of extending
        // tests in contrib.
    }

}