Error in “Remove a component” plugin tutorial

Question

I am trying to follow this tutorials "Remove a component" But getting next Error:

"Uncaught Error: Cannot use object of type Magento\Checkout\Block\Checkout\LayoutProcessor\Interceptor as array in".

The plugins code is:

class removeCheckoutComponent {
    public function aroundProcess($jsLayout) {
        unset($jsLayout['components']['checkout']['children']['steps']['%path_to_target_node%']); 
        return $jsLayout;
    }
}

Why it is not working? The end result I am trying to achieve is to remove city selection from checkout page.

Answer 1

The problem is you're not use the correct signature. Around plugins follow this signature:

function aroundMethod ($subject, \Closure $proceed, $arg1, $arg2, etc...)

Where $subject is the instance of the class whose method is being intercepted, $proceed is a delegate for the method, and then the arguments to the method call follow.

For your use case, you should have:

function aroundProcess (\Magento\Checkout\Block\Checkout\LayoutProcessor $subject, \Closure $proceed, $jsLayout)
{
    unset($jsLayout['components']['checkout']['children']['steps']['%path_to_target_node%']);
    return $proceed($jsLayout);
}

More info here: http://devdocs.magento.com/guides/v2.0/extension-dev-guide/plugins.html