Magento 2.3.4 JS Uncaught ReferenceError with custom payment method

Question

I could need some help.

I've added a custom payment method to our shop following this tutorial: https://webkul.com/blog/create-custom-payment-method-magento2/

So far so good, but after loading the checkout page we get the following error:

Uncaught ReferenceError: Unable to process binding "if: function(){return quoteIsVirtual == 0 }"
Message: Unable to process binding "if: function(){return isIncludingDisplayed() }"
Message: Unable to process binding "if: function(){return haveToShowCoupon() }"
Message: haveToShowCoupon is not defined
    at if (eval at createBindingsStringEvaluator (eval at require.load (b1654aa9974d62289672a4f5a5a23090.min.js:1)), <anonymous>:3:55)
    at ko.computed.disposeWhenNodeIsRemoved (eval at require.load (b1654aa9974d62289672a4f5a5a23090.min.js:1), <anonymous>:373:702)
    at Function.evaluateImmediate_CallReadThenEndDependencyDetection (eval at require.load (b1654aa9974d62289672a4f5a5a23090.min.js:1), <anonymous>:205:240)

Here is a simmilar problem: Uncaught ReferenceError: Unable to process binding "if: function(){return isExcludingDisplayed() }" After Magento 2.3.4 Upgrade Checkout Cart Page

The thing is i have'nt altered the shipping.js files. And when i remove the payment method, the checkout is back in his normal state.

Does someone have an idea what file could have such an impact? Or where i could look to fix it? Or if you need more information, ask. I'll try to give you as many as possible.

Thanks in Advance!

Answer 1

It's hard to answer without seeing all your code but I suspect this error means there is a KO binding in a template that does not exist in the Javascript. Try searching all HTML files for quoteIsVirtual == 0 and hopefully you will find some results and can debug from there.

So fix this find the JS component for that template and ensure the data you're using in the template is accessible.