Unittesting problem with session starting/closing

Question

I am having an problem writing unit tests for an simple session wrapper.

The class itself has some basic functions set , get , exists etc. All these functions have an check assertSessionStart which does the following:

protected static function assertStarted()
{
    if (strlen(session_id()) < 1) {
        throw new Exception("Some text here");
    }
    return;
}

When writing my unit sets, I have the following setUp and tearDown methods. I have these because I want every test that runs to have a fresh session environment.

protected function setUp() {
    session_start();
}
protected function tearDown() {
    session_destroy();
}

Now to the problem, I want an test method which fails when I attempt to use set when I don't have an session started. In order to do this, I will have to destroy the session started in setUp . Like this:

public function testGetWithoutSession() {
        session_destroy();
        $this->setExpectedException('Exception');
        ESL_Session::set('set', 'value');
        session_start();
    }

This however throws an warning 'Trying to destroy uninitialized session'. When I put an echo session_id() right in front of session_destroy though - it shows me that I have an valid session.

Does anyone have experience unit testing session wrappers?

Additional information :

1. PHP Version 5.3.6
2. Linux

Answer 1

It happens because at this point:

    session_destroy();
    $this->setExpectedException('Exception');
    ESL_Session::set('set', 'value'); // HERE <----
    session_start(); // This is not called anymore!

there is an exception and session_start(); isn't called anymore.

My suggestion would be to change to change your tearDown to only call session_destory when there is an active session. So in the tearDown "Only clean up if you have to" .

Answer 2

If you have your nice session class wrapper I discourage to use everytime session_id(); for your assert.

Just put a propierty

private $started = false;

and then in your

protected function setUp() {
    session_start();
    $this->started=true;
}

So you can do your assertStarted() based on $started