Well done!
I was really looking for something like this package!

A was wondering how do you handle the view test.
Using simpletest I solve the issue with a combination of:

$this->get('http://localhost/....../mypage.php');

$this->click('My link to click');

$this->assertText('Text to check');

Is that a correct approach?
What's the correct way using your package?

Not sure whether I'm doing this right, but when I go to /unit_test.php and run any test, it throws this error

"The action you have requested is not allowed."

I'm running CI 2.0.2

Here is my simple controller test. It works perfectly, but it throws lots of exceptions.

class test_user_controller extends CodeIgniterWebTestCase
{
function __construct()
{
parent::__construct();
$this->WebTestCase('User Controller');
}

function testHomePage() {
$this->get('http://localhost/hekmat/');
$this->assertText('Main Page');
}
}

exceptions:
Exception: D:\wamp\www\Hekmat/tests/controllers/test_users_controller.php -> User Controller -> testHomePage -> Unexpected PHP error [Function split() is deprecated] severity [E_DEPRECATED] in [D:\wamp\www\Hekmat\tests\simpletest\url.php line 188]
Exception: D:\wamp\www\Hekmat/tests/controllers/test_users_controller.php -> User Controller -> testHomePage -> Unexpected PHP error [Function split() is deprecated] severity [E_DEPRECATED] in [D:\wamp\www\Hekmat\tests\simpletest\http.php line 524]
Exception: D:\wamp\www\Hekmat/tests/controllers/test_users_controller.php -> User Controller -> testHomePage -> Unexpected PHP error [Function split() is deprecated] severity [E_DEPRECATED] in [D:\wamp\www\Hekmat\tests\simpletest\http.php line 319]
Exception: D:\wamp\www\Hekmat/tests/controllers/test_users_controller.php -> User Controller -> testHomePage -> Unexpected PHP error [Function split() is deprecated] severity [E_DEPRECATED] in [D:\wamp\www\Hekmat\tests\simpletest\http.php line 460]
Exception: D:\wamp\www\Hekmat/tests/controllers/test_users_controller.php -> User Controller -> testHomePage -> Unexpected PHP error [Function split() is deprecated] severity [E_DEPRECATED] in [D:\wamp\www\Hekmat\tests\simpletest\url.php line 188]
Exception: D:\wamp\www\Hekmat/tests/controllers/test_users_controller.php -> User Controller -> testHomePage -> Unexpected PHP error [Function split() is deprecated] severity [E_DEPRECATED] in [D:\wamp\www\Hekmat\tests\simpletest\url.php line 188]

The test_gui.php hard-codes paths: tsk tsk tsk.

Although it's not otherwise kosher, this would be far more useful if you put the CSS directly inline in that file or at least did a file_get_contents() to retrieve the contents of the CSS.

Add support for Selenium; PHPUnit has it yet i think its over-complicate with PHPUnit....

Is there a decent way to test views in isolation (ie without invoking controllers/models, just setting up some variables) using simple_test?

This library would be a lot more useful if some real-world documentation were included -- this should include basic installation scenarios (e.g. is it even possible to put the test files in a directory outside of document root? All my CodeIgniter files save for index.php are not in the docroot, but I see nothing in the comments or README that let me know if this was written in a way that respects that common scenario).

Here are a few examples:

• from unit_test.php, What is this?:
  define('MAIN_PATH', realpath(dirname(FILE)).'/');
• Please put a link back to http://www.simpletest.org/ prominently in your docs -- it's not clear from the de
• From the README, this is useless: "All test files need to be named test_name_folder.php." -- you give example of the filename, but no explanation of where they're supposed to go. What directory?
• Please explain your directory structure. I'm used to putting all my tests into one folder. Why would I put some into a folder named "bugs" and others in a folder named "libraries" etc.
• Update your unit_test.php file so it's clear what areas should NOT be edited. Usually there's a note like "DO NOT EDIT BELOW THIS LINE."
• Add at least one wiki page please: something that describes the project -- it's not even clear that this is an implementation of http://www.simpletest.org/ (include a link please)

With mediocre documentation, a project can never be more than mediocre.