Strict Standards: Declaration of ' ' should be compatible with ' '

Question

I just installed woocommerce 2.0 (on Wordpress) on PHP 5.4, and I got this:

Strict Standards: Declaration of WC_Gateway_BACS::process_payment() should be compatible with WC_Payment_Gateway::process_payment() in D:\my\path\to\htdocs\wordpress\plugins\woocommerce\classes\gateways\bacs\class-wc-gateway-bacs.php on line...

I check the files and found that WC_Payment_Gateway have no method process_payment(). I need to know how to resolve this (not by setting error_reporting()).

What is Strict Standards in PHP exactly?
In what condition so we get that error?

score 20 · Accepted Answer · answered Jun 21 '13 at 11:47

20

WC_Payment_Gateway is defined in abstract-wc-payment-gateway.php and declares a method

function process_payment() {}

while WC_Gateway_BACS defines it as

function process_payment( $order_id ) { ...

(maybe you mixed up WC_Payment_Gateway and WC_Payment_Gateways).

So, different signature (0 parameters vs 1 parameter) -> strict error.
Since it seems* to be used always with one parameter you could change

function process_payment() {}

to

function process_payment($order_id) {}

(*) keep in mind I know of woocommerce only since the last five minutes, so don't take my word for it.

answered Jun 21 '13 at 11:47

VolkerK

95,432
20
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thanks for the explain, maybe you want to check the parent: https://github.com/woothemes/woocommerce/blob/master/includes/class-wc-payment-gateways.php , and the child: https://github.com/woothemes/woocommerce/blob/master/includes/gateways/bacs/class-wc-gateway-bacs.php , the child have `process_payment()` but it's parent doesn't. I tried add that function to the parent but I still get the error. – egig Jun 21 '13 at 11:59
`WC_Payment_Gateways` is not the base class, `WC_Payment_Gateway` is; as noted in my answer text. – VolkerK Jun 21 '13 at 12:21
just realized there is `abstract` folder, :D . Thanks. – egig Jun 21 '13 at 12:29

score 14 · Answer 2 · answered Jun 21 '13 at 11:41

Quote from PHP Manual

In PHP 5 a new error level E_STRICT is available. Prior to PHP 5.4.0 E_STRICT was not >included within E_ALL, so you would have to explicitly enable this kind of error level in >PHP < 5.4.0. Enabling E_STRICT during development has some benefits. STRICT messages >provide suggestions that can help ensure the best interoperability and forward >compatibility of your code. These messages may include things such as calling non-static >methods statically, defining properties in a compatible class definition while defined in >a used trait, and prior to PHP 5.3 some deprecated features would issue E_STRICT errors >such as assigning objects by reference upon instantiation.

You are receiving this error because WC_Gateway_BACS::process_payment() declaration is different than WC_Payment_Gateway::process_payment() (might be not the same amount of parameters etc). If WC_Payment_Gateway has no method process_payment, check it's parent class :)

Also, if you want to disable STRICT errors, add ^ E_STRICT to your error reporting configuration, for example:

error_reporting(E_ALL ^ E_STRICT);

Sajjad Shirazi · Answer 3 · 2014-12-06T07:59:55.343

8

if you wanna keep OOP form without turning any error off, you can also:

class A
{
    public function foo() {
        ;
    }
}
class B extends A
{
    /*instead of : 
    public function foo($a, $b, $c) {*/
    public function foo() {
        list($a, $b, $c) = func_get_args();
        // ...

    }
}

edited Dec 06 '14 at 07:59

answered Dec 06 '14 at 07:51

Sajjad Shirazi

2,657
26
24

9

Ugly as hell, but sometime needed. – Markus Schulte Dec 18 '14 at 15:16
This is never needed. – sepehr Sep 09 '17 at 13:19

score 2 · Answer 4 · edited Nov 24 '16 at 21:51

When you are using the same function in a parent class and a child class, but the child class needs parameters while the parent one not, you'll get the Strict Standards error.

Example

Manager:

public function getAtPosition($position)
{
    foreach ($this->getList() as $obj)
    {
        if ($obj->getPosition() == $position)
            return $obj;
    }

    return null;
}

MenuManager extends Manager:

public function getAtPosition($position, $parent)
{
    foreach ($this->getList() as $m)
    {
        if ($m->getParent() == $parent && $m->getPosition() == $position)
            return $m;
    }

    return null;
}

This example will generate an error:

Strict standards: Declaration of MenuManager::getAtPosition() should be compatible with Manager::getAtPosition($position)

Because we don't have the same arguments to the function, so let's trick this and add arguments, even though we're not using them!

Manager:

public function getAtPosition($position, $dummy = 0) // Dummy to avoid Strict standards errors
{
    foreach ($this->getList() as $obj)
    {
        if ($obj->getPosition() == $position)
            return $obj;
    }

    return null;
}

MenuManager extends Manager:

public function getAtPosition($position, $parent = 0)
{
    foreach ($this->getList() as $m)
    {
        if ($m->getParent() == $parent && $m->getPosition() == $position)
            return $m;
    }

    return null;
}

Only one to be careful is that when using getAtPosition() from MenuManager.class.php, be sure you are actually sending 2 parameters, as we have to declare $parent = 0 in order to match the parent's declaration.

Every class extending Manager and not containing getAtPosition() will use the method from Manager.

If declared in a child class, php will use the method from the child class instead of the parent's one. There is no overloading in PHP, so that is how I worked around it until it is properly implemented.

score 1 · Answer 5 · edited May 23 '17 at 11:53

1

Here is a better answer - https://stackoverflow.com/a/9243127/2165415

for example,
parentClass::customMethod($thing = false) and
childClass::customMethod($thing)
so, when you call customMethod() for the class, it may trigger the error, because the child's method hasn't defined a default value for the first argument.

edited May 23 '17 at 11:53

Community

1
1

answered Jul 11 '14 at 18:12

T.Todua

53,146
19
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237

Strict Standards: Declaration of ' ' should be compatible with ' '

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