fix: allow calling fetch with data: URL

[danielniccoli]

Fixes #10657

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[Conduitry]

I'm wondering whether we instead just want to ensure that the URLs begin with \w+:, and what sort of false negatives that would result in. I don't know. I don't know whether it makes sense to explicitly call out data: separately from all of the other URL schemes.

[danielniccoli]

Edit

Then we should discuss proper scheme identifications. As per https://www.rfc-editor.org/rfc/rfc3986#section-3.1 schemes are defined as

scheme = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )

A regular expression that matches this is /^[a-z][a-z\d+\-.]+:/i. This should catch all possible edge cases, but leaves it to the developer to pass a registered or valid scheme.

I will change the pull request, if that is an agreeable approach.

[danielniccoli]

@Conduitry @benmccann Would the approach above be acceptable? I'm ready to update this PR. Please let me know.

[benmccann]

That sounds fine, but I think your translation from text to reflex omitted uppercase letters and "+"

[danielniccoli]

Replaced by #10699 (Sorry, pull requests are somewhat challenging for me 🙂 )