Describe the problem you are trying to fix (provide as much context as possible)

I want to reject 'http:/' as an invalid URL

const Joi = require('@hapi/joi')
Joi.validate('http:/', Joi.string().uri())

This does not raise an error. What I expect is:

ValidationError: "value" must be a valid uri

There was a similar report in #1732 for http:// (with two slashes) which was addressed in d7ff4fa. However, that code still accepts http:/ (with one slash).

Which API (or modification of the current API) do you suggest to solve that problem ?

Modify the URI regex generator to reject this case.

Are you ready to work on a pull request if your suggestion is accepted ?

I got as far as writing a test case, though I wasn't sure how to modify the regex generator to solve this.