Functions file causes collisions if package is used more than once

[schlessera]

The functions.php file is pulled in throught the Composer autoloader file mechanism: https://github.com/beberlei/assert/blob/master/composer.json#L20

If this package is used more than once in one PHP session (my use case is several WordPress plugins including it), this causes a fatal error:

Fatal error: Cannot redeclare Assert\that() [...]

I know that Composer should be used at the site level, not multiple times in one site. However, this could easily be fixed to allow for that use case, too, which would at least simplify the development process.

[schlessera]

Sorry for the spam in here, didn't realize that GitHub would pull in my change logs... :)

[shadowhand]

I disagree with this change, as this is not a failure in this package or in composer. The problem only exists when someone uses require 'vendor/autoload.php' instead of using require_once. This lowers the performance (a minuscule amount, I know) of every single request.

[shadowhand]

Which is to say, the problem should have been resolved by submitting patches to the offending WP plugins, instead of brute forcing a solution in this package.

[schlessera]

@shadowhand The problem is not due to WP plugins. This problem exists any time you have an app/framework that doesn't use Composer at the root level, and you still want to use Composer for whatever extension mechanism it uses. It is a limitation of PHP (that cannot autoload functions, only class-like elements), and the above patch just makes sure the assert library can still be used in such scenarios.

[schlessera]

Ah, btw, just wanted to state that require_once will not fix the above issue in many cases, as it does not work on basis of the class to load, but rather on the filepath to retrieve the class from. If you require_once the same file from two different locations, both will be loaded.

[shadowhand]

If you require_once the same file from two different locations, both will be loaded.

That's an incorrect statement. As per the docs:

The require_once statement is identical to require except PHP will check if the file has already been included, and if so, not include (require) it again.