bug in Secure Fields cardNumber in validityChange event

[ihojmanb]

I'm having trouble with card validation, and I think it's possibly a bug, but correct me if I'm wrong.

I'm using the following code to check the validity of every secure field:

      secureFieldElement.on("validityChange", (data) => {
        const { field, errorMessages } = data;
        console.log(`${field}:errorMessages:`, errorMessages);
        if (errorMessages[0]) {
          console.log(`there is an error with ${field}`);
          // ...
          // do something with the error
        } else {
          console.log("no errors presented");
         // do something else
        }
      });

(I found that code somewhere in the docs, not sure where)

So when I use the test card number available in the documentation, say 5416 7526 0258 2580, and type the first 8 digits (what is known as the bin) I get no errorMessages. This will be understood by my program as if the typed digits are a valid card number, hence bypassing the form validation, enabling my user to submit an incorrect card information.

If I delete the last digit -- now having only 7 digits in the input field -- I receive the following error message object:

{cause: 'invalid_length', message: "cardNumber should be of length '16'."}

If I retype the deleted message, this error object repeats.

So my question is, why is this not the expected behavior from the beginning?

Here is a sequence of the events described:

1. first 8 digits
   
2. delete last digit
   
3. retype last digit
   

[ihojmanb]

To endorse this, if we type 8888 8888, which is an invalid bin, the validatityChange event does not detect any errors

[ihojmanb]

the same goes with 8888 8888 88 which is neither a valid card number, but the validation does not seem to apply either

[icaldana]

Hello @ihojmanb!

We apologize for the delay and for the inconvenience it may have caused to your workflow. Let's clarify some points:

• Not every card has 16 digits, the market range is from 8 to 19 characters, depending on the card network.
• With the first 8 characters, aka the bin, we can identify the card network and then know how many digits that card must have. So until 7 digits, we only know it should have between 8 and 19 numbers.

I was performing some testes, and I've noticed the behavior I've described isn't always happening, therefore, an internal bug ticket as created to polish this behavior. I would like to thank you for reporting this and I promise I will handle it with care.

Thank you.

[ihojmanb]

thanks for the support @icaldana, appreciate it!