Gray color is not correctly cast to a string about color.js

[facelessuser]

What hue would you suggest gray has? The reason why you get an undefined hue (none) is because the color is achromatic and has no hue.

[star-over]

I suggest use 0 instead none when color stringify. So, I expect hsl(0 0% 50.196%) but not a hsl(none 0% 50.196%)

Because converting color with none to other format is another issue:

(new Color("hsl(none 0% 50.196%)")).to("srgb").toString()
>>> 'rgb(none none none)'

but with 0 instead none it works corretly:

(new Color("hsl(0 0% 50.196%)")).to("srgb").toString()
>>> 'rgb(50.196% 50.196% 50.196%)'

[facelessuser]

none is now supported in the CSS spec and has been implemented in a number of browsers. Gray doesn't actually have a red (0deg) hue, but regardless of technicalities of what is more correct, I can imagine some people desiring a way to serialize without none. There was an option to do so for some amount of time, but it was removed in e28cd6a.

Below does look like a bug to me though. Undefined values should be handled before conversion, but that does not appear to be happening currently.

new Color("hsl(none 0% 50.196%)").to("srgb").toString()
>>> 'rgb(none none none)'

[star-over]

I just fixed problem for a while with a .toString().replaceAll("none", "0") after any stringify.

[facelessuser]

I personally think an option to allow omitting none in serialization seems reasonable, but thenone conversion issue should definitely get fixed.

[facelessuser]

I've created a PR (#476) to adjust the bad "none" handling across the library.

@svgeesus and @LeaVerou would need to make a decision on whether it is desired to expose conditional "none" serialization. If they decided that they wanted to move forward with this, I'd be happy to make the PR.