Update semver regex to not swallow trailing .

[itowlson]

Fixes #128.

The new regex is more complicated than wac likely needs - for example, it includes capture groups that the lexer discards. The reason for choosing it was that it is suggested by the official semver site (https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string). Of course it can be trimmed back if necessary but that introduces the possibility of me messing it up... grin

[itowlson]

The tests are red because some test cases use a version of 1. Should that be allowed, or should I tweak the tests to use e.g. 1.0.0?

[calvinrp]

The tests are red because some test cases use a version of 1. Should that be allowed, or should I tweak the tests to use e.g. 1.0.0?

I think we should fix the test cases to use a valid semver , like 1.0.0.

[itowlson]

Ah, correction. Those tests are meant to be invalid semvers. The tests are for the error message, and it looks like the new regex has changed that from

  × `1` is not a valid semantic version
   ╭─[tests/parser/fail/invalid-path-semver.wac:3:23]
 2 │ 
 3 │ import i: foo:bar/baz@1;
   ·                       ┬
   ·                       ╰── invalid version
   ╰────

to

  × unexpected token was encountered
   ╭─[tests/parser/fail/invalid-path-semver.wac:3:11]
 2 │ 
 3 │ import i: foo:bar/baz@1;
   ·           ─────────────
   ╰────

which is definitely a step backward! So a custom regex might be needed after all.

[peterhuene]

Looking back, I think I left it the more generic regex and then did validation via the semver crate on what was matched for this reason, i.e. the fact that if it fails to match, we'll treat it as an unknown token.

Perhaps we simply just slap a [^\.] to the end of the existing expression?

[itowlson]

@peterhuene I think I have something that works - forgiving enough to allow invalid things in version positions so that better errors can be given later, but strict enough to consume dots only when within the regex. I've added a test case for the issue and everything passes locally so 🤞

[peterhuene]

Looks good, thanks for fixing this!