Use important properties for optimalization opportunities

[Venemo]

In cases where there are not enough non-important properties for compacting into a shorthand, but there could be when taking important properties into account, we can use them to our advantage.

For example, this code:

foo {
  margin-top: 1px;
  margin-right: 2px;
  margin-bottom: 3px !important;
  margin-left: 4px !important
}

is equivalent to the following:

foo {
  margin: 1px 2px 0 0;
  margin-bottom: 3px !important;
  margin-left: 4px !important
}

Reasoning:
In the example it is safe to add a fake 0 for non-important margin-bottom and margin-left because their values are going to be overridden by the important properties. However, there is a visible gain in terms of CSS size.

[Venemo]

NOTE: I've already implemented this in my fork, just opened the ticket in order to make you aware of this possibility.

[GoalSmashers]

👍 good stuff

[XhmikosR]

I'm not sure this makes sense code-wise though. The resulting CSS might be smaller, sure, but it's like going forward and then changing direction to go backwards...

[Venemo]

@XhmikosR Sorry, I don't quite get your point

[GoalSmashers]

@XhmikosR I don't get it either - our goal is the smallest CSS possible no matter what, right?

[XhmikosR]

I guess I was thinking it from a code quality point of view. It's a hack, but it should work, so ignore my previous comment.

[Venemo]

@XhmikosR Did you actually read my code and think it's a hack? If so, I'm open to your suggestions on how to implement it differently.

[XhmikosR]

I didn't read your code; I read the example above... It's a hack because you set one property to 0 knowing it will be overwritten anyway, that's what I meant.

I can't think of any other approach for this specific example, so your way seems to be the best at this point if we want to handle this case.

[GoalSmashers]

@XhmikosR I believe there is no other way. We are fine as long as it renders the same way.

[XhmikosR]

Yeah. I don't think there would be any issues with any browser. The last property is always used as far as I know.

[GoalSmashers]

Fixed with #249.