[BUGFIX] Parse calc split over multiple lines

[scq]

calc() expressions that are multiline, where one line ends on an operator, currently fail to parse. E.g.

.btn {
  --foo: calc(
    var(--bar) +
      (var(--baz) + var(--qux)) * 2
  );
}

This is because the code is looking for a space character following the operator, and failing when it sees a newline instead.

[coveralls]

coverage: 62.467% (+2.8%) from 59.658%
when pulling 3de58cd on totara:calc-parsing-fix
into fe29992 on MyIntervals:main.

[JakeQZ]

Hi @scq,

Thanks for this. I concur that the spec allows any type of whitespace around the + and - operators (requiring at least one whitespace character).

To cover all types of whitespace, we can use preg_match with \s (via the 'Safe' library).

As part of this change, it would be good to also allow all types of whitespace before the operator (as well as after) - with tests covering that too.

We're aiming to move the tests away from functional tests to dedicated unit tests. I note there is not yet a CalcFunctionTest. Adding such a TestCase for the tests related to this change would be good.

Also, could you add an entry to the CHANGELOG.md file (in the root folder of the repository)?

[scq]

Sweet, thanks for the review! Made those changes.

[JakeQZ]

Wow, this is amazing and absolutely perfect.

I wasn't expecting such a comprehensive test suite. Appreciate the time you have taken, which has saved us some :))

Thank you ever so much <3

We are on the lookout for additional collaborators if you are interested...

[JakeQZ]

coverage: 62.467% (+2.8%) from 59.658% when pulling 3de58cd on totara:calc-parsing-fix into fe29992 on MyIntervals:main.

That's impressive too :)

[JakeQZ]

These PHPDoc annotations are actually redundant, since the types are in the method signature.

[JakeQZ]

Looking again, I found a few other minor nitpicks.

But this is a great set of tests, so I was keen to get it merged.

[JakeQZ]

I forgot to mention that we put the changelog entries in reverse chronological order (though I'm not sure why).