Fix false positives for selector lists and shared-line comments in comment-empty-line-before

[ntwb]

Describe the issue. Is it a bug or a feature request (new rule, new option, etc.)?

A bug where multiple shared-line comments using the comment-empty-line-before rule returns false results.

via https://github.com/stylelint/stylelint/tree/master/lib/rules/comment-empty-line-before

"If the comment is the very first node in a stylesheet then it is ignored. Shared-line comments are also ignored."

Which rule, if any, is this issue related to?

comment-empty-line-before

What CSS is needed to reproduce this issue?

/* comment */
.ok { /* comment */
  color: pink;
}

/* comment */
.foo, /* comment */
.bar { /* comment */
  color: pink;
}

What stylelint configuration is needed to reproduce this issue?

{
  "rules": {
    'comment-empty-line-before': [ 'always', {
      ignore: ['stylelint-commands'],
    } ],
  }
}

Which version of stylelint are you using?

8.0.0

How are you running stylelint: CLI, PostCSS plugin, Node API?

n/a

Does your issue relate to non-standard syntax (e.g. SCSS, nesting, etc.)?

No

What did you expect to happen?

No warnings to be flagged.

What actually happened (e.g. what warnings or errors you are getting)?

The following warnings were flagged:

> test.css            
 8:8  ✖  Expected empty line before comment   comment-empty-line-before

[ntwb]

Here's a couple of failing tests that should pass:

diff --git lib/rules/comment-empty-line-before/__tests__/index.js lib/rules/comment-empty-line-before/__tests__/index.js
index be684390..3b867c25 100644
--- lib/rules/comment-empty-line-before/__tests__/index.js
+++ lib/rules/comment-empty-line-before/__tests__/index.js
@@ -76,6 +76,10 @@ testRule(
       {
         code: "a {\n\n  /* comment */\n  color: pink;\n}",
         description: "first-nested with empty line before"
+      },
+      {
+        code: "a {\n /* comment */\n  color: pink;\n}",
+        description: "shared-line comment should be ignored"
       }
     ],
 
@@ -147,6 +151,10 @@ testRule(
         code:
           "a {\ncolor: pink;\n/* stylelint-disable something */\ntop: 0;\n}",
         description: "no newline before a stylelint command comment"
+      },
+      {
+        code: "a {\n /* comment */\n  color: pink;\n}",
+        description: "shared-line comment should be ignored"
       }
     ]
   })

[jeddy3]

Will this be fixed by #2827?

Neither of the additional tests above contain shared-line comments. So, I'm not sure those tests should pass.

[jeddy3]

I can replicate this with 8.1.1. Very strange bug.

The following:

any selector,
.bar { /* comment */
  color: pink;
}

Will produce a violation:

2:8 error Expected empty line before comment (comment-empty-line-before)

Whereas the following two produce no violations:

.bar { /* comment */
  color: pink;
}

any rule { }
.bar { /* comment */
  color: pink;
}

[hudochenkov]

Demo with an issue.