Fix false positives for dollar variables in no-invalid-position-at-import-rule

[XhmikosR]

Clearly describe the bug

Should allow dollar variables

Which rule, if any, is the bug related to?

e.g. no-invalid-position-at-import-rule

What code is needed to reproduce the bug?

e.g.

/*!
 * Bootstrap Reboot v5.0.0-beta3 (https://getbootstrap.com/)
 * Copyright 2011-2021 The Bootstrap Authors
 * Copyright 2011-2021 Twitter, Inc.
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
 * Forked from Normalize.css, licensed MIT (https://github.com/necolas/normalize.css/blob/master/LICENSE.md)
 */

@import "functions";
@import "variables";
// Prevent the usage of custom properties since we don't add them to `:root` in reboot
$font-family-base: $font-family-sans-serif; // stylelint-disable-line scss/dollar-variable-default
$font-family-code: $font-family-monospace; // stylelint-disable-line scss/dollar-variable-default
@import "mixins";
@import "reboot";

What stylelint configuration is needed to reproduce the bug?

e.g.

{
  "rules": {
    "no-invalid-position-at-import-rule": true
  }
}

Which version of stylelint are you using?

e.g. 13.13.0

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

e.g. "CLI with stylelint "**/*.css" --config myconfig.json"

What did you expect to happen?

e.g. "No warnings to be flagged."

What actually happened (e.g. what warnings or errors did you get)?

e.g. "The following warnings were flagged:"

bootstrap/scss/bootstrap-reboot.scss
 14:1  ✖  Unexpected invalid position @import rule   no-invalid-position-at-import-rule
 15:1  ✖  Unexpected invalid position @import rule   no-invalid-position-at-import-rule

Refs #5202 (comment)

[jeddy3]

@XhmikosR Thanks for the report and for using the template.

Let's change the logic in the rule so that it only warns if @import is preceded by either a standard syntax:

• rule, i.e. isStandardSyntaxRule(rule)
• at-rule, i.e. isStandardSyntaxAtRule(atRule)

This will be true to the wording of the spec while allowing non-standard syntax, like dollar variables.

I've labelled the issue as ready to implement. Please consider contributing if you have time.

There are steps on how to fix a bug in a rule in the Developer guide.