bug: `/#/` in URLs is failing validation

[adrienthiery]

Hi there,
following #285 's report, we also saw a regression on testing validity or a URL, namely https://exchange.jetswap.finance/#/swap ( ValidationError(func=url, args={'value': 'https://exchange.jetswap.finance/#/swap'})

The /#/ in there is probably the thing making it match as invalid, sadly it is a common side-effect of some JS UI libraries.

As the last comments mention, it would indeed be super nice to follow the common semver practice in bumping a major version in case of breaking change, and at least mention in the releases description when a breaking change is included. 🙏

[yozachar]

The /#/ in there is probably the thing making it match as invalid, sadly it is a common side-effect of some JS UI libraries.

Hi @adrienthiery, indeed, /#/ was causing trouble, but this was not an intentional breaking change, unlike the case in #285 (comment). It is an edge case which was neither present in the tests before nor after v0.20.0. But since the validation algorithm changed, the edge case popped up.

Currently src/validators/url.py has:

validators/src/validators/url.py

Lines 118 to 119 in ee088fa

	if fragment:
	optional_segments &= all(char_to_avoid not in fragment for char_to_avoid in ("/", "?"))

When the URL https://exchange.jetswap.finance/#/swap is passed, fragment = /swap, which makes optional_segments = false since / is present in the fragment, which is (an) unusual (side-effect) as you suggest.

---

Here's the patch.

    if fragment:
+      fragment = fragment.lstrip("/") if fragment.startswith("/") else fragment
        optional_segments &= all(char_to_avoid not in fragment for char_to_avoid in ("/", "?")

This will handle all the URLs with /#/some-value fragment in them, but I think there will be more edge cases, only time will tell. PRs are welcome!

[cfi-gb]

but I think there will be more edge cases, only time will tell.

It seems a few additional ones have been found so far and #296 has been raised as a follow-up with additional different examples.