无法进行单元测试:在运行每个测试之前 $_SESSION 清空

I can't unit test my code.

$_SESSION clears every time the next test is run. When I run testStartProductSession() my object adds some data to the $_SESSION variable. But when I run the next test method ( testSessionIdIsKept() ) the $_SESSION is empty again.

Looks like $_SESSION becomes local variable when unit testing.

I don't know what else to do. Please check the output bellow:

// session_start() on bootrap.php;

class MC_Session_ProductTest extends PHPUnit_Framework_TestCase
{

    /**
     * @return MC_Session_Product
     */
    public function getObject()
    {
        // make getInstance() return new instance instead of singleton instance
        MC_Session_Product::$isUnityTest = true;
        $object = MC_Session_Product::getInstance();
        $object->getWsClient()->setServerListUrl(SERVER_LIST_URL);
        return $object;
    }

    /**
     * All tests pass
     * @depends testSetParam
     */
    public function testStartProductSession()
    {
        $developerId = PARAM_DEVELOPER_ID;
        $productCode = PARAM_PRODUCT_CODE;
        $productVersion = PARAM_PRODUCT_VERSION;
        $platform = PARAM_PLATAFORM;
        $deviceType = PARAM_DEVICE_TYPE;
        $locale = PARAM_LOCALE;

        try {
            $object = $this->getObject();
            $object->startSession($developerId, $productCode, $productVersion,
                                  $platform, $deviceType, $locale);
            $this->assertTrue($object->sessionStarted());
        } catch (Exception $e) {
            $this->fail('Fail to start session: ' . $object->getLastUrl());
        }

        echo "$_SESSION in testStartProductSession(): ", print_r($_SESSION, 1);
        return $object;
    }

    /**
     * Test fails because $_SESSION is empty again
     * @depends testStartProductSession
     */
    public function testSessionIdIsKept(MC_Session_Product $lastObject)
    {
        echo "$_SESSION in testSessionIdIsKept(): ", print_r($_SESSION, 1);
        $object = $this->getObject();
        // fails
        $this->assertTrue($lastObject->sessionStarted());
        $this->assertTrue($object->sessionStarted());
        $this->assertEquals($lastObject->getSessionId(), $object->getSessionId());
        return $object;
    }
}

/* ###### Output


$_SESSION in testStartProductSession():
Array
(
    [__MC] => Array
        (
            [MC_Session_Product] => Array
                (
                    [keyOne] => 'valueOne'
                    [sessionId] => 'someId'
                )

        )

)
$_SESSION in testSessionIdIsKept():
Array
(
)

*/

解决方案

PHPUnit resets all global variables--including $_SESSION--to their starting values before each test method. You can disable this for a test case by overriding the $backupGlobals instance property to false. This does not work from the setUp() method.

class MyTest extends PHPUnit_Framework_TestCase
{
    protected $backupGlobals = FALSE;

    // ...
}

See Global Variables and PHPUnit for further details.