Correction of the work with comments and general improvements

[Ulyanov-programmer]

List of changes:

• Fixed a bug where rules with comments without properties could lose comments embedded in them.
• The code that was duplicated several times was deleted and moved to a new function.
• General code improvements: foreach has been replaced with for, and some methods have been optimized.

All tests were passed correctly.

[ai]

Is it a expected output?

.block {
  /* Element comment */
  .element {
  }
}

will not be moved too?

[Ulyanov-programmer]

I didn't understand you.
Your code should be converted to:

.block {
  /* Element comment */
}
.block .element {
}

It was from this logic that I transformed the test.

UPD: The code that was previously in the test was wrong - comments should not have left the rules in which they were embedded.
I've changed the logic and tests so that they stay inside the rules.

[ai]

Your code should be converted to

Is it expected output?

Seems like very soon other developers will come and will open new issues asking to not move this kind of comments

[Ulyanov-programmer]

Do you really think that the comments embedded in the rules should remain outside?
If a comment is embedded in a rule, it should remain in it. If a comment is not embedded in a rule, it must be outside of it. It's logical, isn't it?

[Ulyanov-programmer]

In fact, the plugin originally assumed this logic - when I wrote a comment in the rule, it remained in it (see the original issue). But in one of the cases there was a mistake that I fixed.

[Ulyanov-programmer]

I use the library to convert CSS to HTML. In order to set the text for the elements, you need to enter it somewhere.
At first, custom properties were the solution, but they have a problem - they do not allow you to process multi-line texts.
For the correct processing of such text, I decided to use comments with a special mark, like this:

p {
  /* text:
    Lorem ipsum ipsum lorem
    Выходила на берег Катюша
  */
   a {
    --attr-href: 'https://www.npmjs.com/package/posthtml';
    --attrs: 'target="_blank" rel="noopener noreferrer"';
  }
}

Assigning text from comments when it is outside tags is quite problematic and illogical - the text must be inside the tag anyway, moreover, based on some features of working with CSS, I have an option to write text before and after the tag:

p {
  /* text-before:
    Lorem ipsum ipsum lorem
    Выходила на берег Катюша
  */
}

[ai]

Got it. The problem is that it is unique feature for mostly 1-2 people. I do not want to change behvaiour for everyone.

The suggestions:

1. You write a plugins which will run before (to hide comment to Rule.props) and after postcss-nested (to restore them).
2. We can add keepComment option to the postcss-nested but only if it will be very small to not reduce code maintaibility.

[Ulyanov-programmer]

There is another option: most often (a matter of formatting) there is an empty space between the properties and the nested rule. If they want to describe a rule with a comment, the comment is "pressed" to the rule from above, leaving no space.

This can be used to separate comments into those that cannot be left inside the rule and those that can.

Example:

p {
  /* comment inside the rule, save as is */

  /* comment for the rule below, move with the rule */
  a {
  }
}

[ai]

Yes, let's use empty new line to detect it

[Ulyanov-programmer]

Okay, I'll take care of it in the next few days and let you know when the result is.