input.setCustomValidity() on custom validation failure?

[jwalton]

Hey, just wondering if you've though about calling input.setCustomValidition(error) to set a custom validation message (around about here)? Is there some reason you're not doing this? Does this have some hidden pitfalls I'm not aware of?

You'd probably want to only do this if a "customValidation" flag was set or something, because if people are using non-strings as errors or string that need to be translated or something, it would be nice for there to be a way to turn it off... Or, maybe have a getCustomValidationMessage() function which returns a string or undefined so people can translate or do whatever on their own?

[wsmd]

I think this is a great idea, and will make a nice addition to the lib.

It has come up before - see #112

Does this have some hidden pitfalls I'm not aware of?

While trying to answer the question posted there, I realized that the tricky part with custom errors is that we have to clear them as soon as the user starts typing, otherwise the UX could be jarring.

I managed to get around that with current implementation by using validteOnBlur.

For more info: https://codesandbox.io/s/setcustomvalidity-v2ue3