PHP coding standards

Generally, PHP code should comply with the common PSR recommendations. Every code file must contain one class that complies with PSR-0 or PSR-4 autoloading standard. This also means the class name must be equal to the file name, otherwise there will be a fatal error in X-Cart autoloader code.

Any additional files inside <X-Cart>/classes directory are forbidden to have *.php extension and non-PSR0 basename. When making backups, the best practice is to append .bkp or some other suffix to file extension instead of modifying its basename.

The code style must comply with the PSR-2 recommendation. Here is the quick overview:

<?php
namespace XLite\Module\VendorName\ModuleName;

use FooInterface;
use BarClass as Bar;
use OtherVendor\OtherPackage\BazClass;

class Foo extends Bar implements FooInterface
{
    /**
     * [sampleFunction description]
     * @param  {[type]} $a [description]
     * @param  {[type]} $b [description]
     * @return {[type]}    [description]
     */
    public function sampleFunction($a, $b = null)
    {
        if ($a === $b) {
            bar();
        } elseif ($a > $b) {
            $foo->bar($arg1);
        } else {
            BazClass::bar($arg2, $arg3);
        }
    }

    /**
     * [bar description]
     * @return {[type]} [description]
     */
    public static function bar()
    {
        // method body
    }
}

We encourage using phpDoc to provide API description.

Due to X-Cart architecture, it is forbidden to make private methods, use protected instead. The reason for that is that decorator system should be able to modify any behaviour of the module through PHP extending.

Testing against PSR-2

Before submitting a module to X-Cart 5 marketplace, you need to verify its code style. It can (and should) be done automatically by running code analyzers. As instance, you can verify the module's code by running the following command in your command line:

phpcs --standard=PSR2 path/to/your/files

Of course, PHP codesniffer must be installed in your system from PEAR or by hand in order to successfully run this command.