allow extra spaces in headerCssClass

[jesenko]

Extra spaces in class dom attribute are allowed in html (e.g. class="some-class other-class "). SlickGrid should probably also behave the same way (or at least fail with some meaningfull validation error).

This commit just ignores all extra spaces in headerCssClass (between individual classes or leading / trailing).

I did not add E2E test for this, seems a bit overkill to add example html file for testing such minor case...
The error can be reproduced however by e.g. adding some space at the beginning / end of headerCssClass in examples/example-web-component-pubsub-esm.html:193

[ghiscoding]

it seems like developers looking for trouble lol... I did some perf tests and this seems faster than trim() + regex, so I guess that's ok even though it's less readable. Note that there's like 15-20 use of these things across the project, just fixing 1 probably isn't good enough, I would suggest to add a simple function in the slick.core Utils and reuse it everywhere needed

// slick.core.ts Utils
function wordSplit(s = ''): string[] {
    return s.split(' ').filter(cls => cls);
}

then use it everywhere

header.classList.add(...Utils.wordSplit(classname));

there's a few .split(' '), just do a solution search, however not all of them require the fix, some of them are used just for reading from existing DOM elements which don't require any fixes

[ghiscoding]

@jesenko Thanks the PR is looking good, but I just find the method name to be a little long, could we simply use classNameToList instead?

[jesenko]

@ghiscoding renamed method to classNameToList, thank you for suggestion — I did not like the long name either, but was unable to come up with clear and concise naming :)

[ghiscoding]

Shorter is better and we stayed concise so that's looking good now. Thanks for the contribution :)

[ghiscoding]

ohh I just noticed that your PR didn't include fix or feat, please make sure to include that in your PRs next time so that the changelog can automatically detect it and assign to the proper group in the changelog, in the case of your PR it won't detect anything. This automation works when using Conventional Commits which is what most projects use nowadays

I had to do git commit --amend to manually fix your PR subject

[ghiscoding]

Shipped with v5.7.1 release, thank you