I think I just invented a new testing pattern - The Binary Canary.
Basically, I was grouping my PHPUnit tests into a test suite and I realized that my TestCase super-classes were "failing" because they had no tests in them. Obviously this is intentional - only the specific sub-classes would have tests.
I guess I could have made the TestCase super-classes abstract, but instead I added this to the highest-level TestCase class:
/*
* global test plumbing here
*/
class Sfx_TestCase extends PHPUnit_Framework_TestCase
{
public function setUp()
{
// more global test plumbing here
}
public function test_Binary_Canary()
{
$this->assertEquals(
"Binary Canary says test plumbing is working.",
"Binary Canary says test plumbing is working."
);
}
}
My little binary canary serves two purposes:
- It adds an "always-pass" test to each of my TestCase classes so they don't throw up any more PHPUnit warnings.
- Because my TestCase classes set up context-specific test plumbing, the binary canary test inherited by each of them now alerts me if I screw up any of my test plumbing - and tells me the specific area.
For example:
class Sfx_Db_TestCase extends Sfx_TestCase
{
public function setUp()
{
parent::setUp();
// Db-specific test plumbing
}
}
And:
class Sfx_Controller_TestCase extends Sfx_TestCase
{
public function setUp()
{
parent::setUp();
// Controller-specific test plumbing
}
}
Just like the coal-miner canaries of old, this mechanism gives me a simple yes/no signal as to whether or not my test plumbing will soon kill me, and which plumbing code is the culprit.
