no-mergeable-selectors not working properly with nth-child(even) nth-child(odd)

[adrifmonte]

What version of Sass Lint are you using?

Older (working) version:

gulp-sass-lint@1.2.0 node_modules/gulp-sass-lint
├── through2@2.0.1 (xtend@4.0.1, readable-stream@2.0.6)
└── gulp-util@3.0.7 (array-differ@1.0.0, lodash._reevaluate@3.0.0, beeper@1.1.0, lodash._reescape@3.0.0, lodash._reinterpolate@3.0.0, array-uniq@1.0.3, object-assign@3.0.0, replace-ext@0.0.1, has-gulplog@0.1.0, fancy-log@1.2.0, minimist@1.2.0, vinyl@0.5.3, chalk@1.1.3, lodash.template@3.6.2, gulplog@1.0.0, multipipe@0.1.2, dateformat@1.0.12)

sass-lint@1.8.2 node_modules/sass-lint
├── path-is-absolute@1.0.0
├── lodash.kebabcase@4.1.1
├── lodash.capitalize@4.2.1
├── merge@1.2.0
├── commander@2.9.0 (graceful-readlink@1.0.1)
├── util@0.10.3 (inherits@2.0.1)
├── gonzales-pe@3.3.4 (minimist@1.1.3)
├── glob@7.0.5 (fs.realpath@1.0.0, inherits@2.0.1, once@1.3.3, inflight@1.0.5, minimatch@3.0.3)
├── fs-extra@0.30.0 (rimraf@2.5.4, jsonfile@2.3.1, graceful-fs@4.1.5, klaw@1.3.0)
├── js-yaml@3.6.1 (esprima@2.7.2, argparse@1.0.7)
└── globule@1.0.0 (minimatch@3.0.3, lodash@4.9.0)

Newer (buggy) version:

gulp-sass-lint@1.2.0 node_modules/gulp-sass-lint
├── through2@2.0.1 (xtend@4.0.1, readable-stream@2.0.6)
└── gulp-util@3.0.7 (array-differ@1.0.0, array-uniq@1.0.3, beeper@1.1.0, lodash._reescape@3.0.0, lodash._reevaluate@3.0.0, object-assign@3.0.0, lodash._reinterpolate@3.0.0, replace-ext@0.0.1, has-gulplog@0.1.0, fancy-log@1.2.0, minimist@1.2.0, vinyl@0.5.3, chalk@1.1.3, lodash.template@3.6.2, gulplog@1.0.0, multipipe@0.1.2, dateformat@1.0.12)

sass-lint@1.9.0 node_modules/sass-lint
├── path-is-absolute@1.0.0
├── lodash.capitalize@4.2.1
├── lodash.kebabcase@4.1.1
├── merge@1.2.0
├── commander@2.9.0 (graceful-readlink@1.0.1)
├── util@0.10.3 (inherits@2.0.1)
├── glob@7.0.5 (fs.realpath@1.0.0, inherits@2.0.1, inflight@1.0.5, once@1.3.3, minimatch@3.0.3)
├── gonzales-pe@3.4.4 (minimist@1.1.3)
├── fs-extra@0.30.0 (rimraf@2.5.4, graceful-fs@4.1.5, klaw@1.3.0, jsonfile@2.3.1)
├── js-yaml@3.6.1 (esprima@2.7.2, argparse@1.0.7)
└── globule@1.0.0 (minimatch@3.0.3, lodash@4.9.0)

Please include any relevant parts of your configuration

  no-mergeable-selectors:
    - 2

What did you do? Please include the actual source code causing the issue.

.fake-field {
  tbody {
    tr:nth-child(even) {
      background: lighten($theme-color-primary, 50%);
    }
    tr:nth-child(odd) {
      background: #FFFFFF;
    }
  }
}

What did you expect to happen?

I expected no issues, since those two rules aren't mergeable!

What actually happened? Please include any error messages given to you by Sass Lint.

Rule .fake-page .fake-table tbody tr:nth-child(null) should be merged with the rule on line 66 (no-mergeable-selectors)

If you're using a IDE plugin have you tried the CLI too?

The former version (1.8.2) didn't have that bug. After an npm update, it was updated to version 1.9.0, and this bug was reproduced (see "What version of Sass Lint are you using?" section).
I have tested running the sass-lint with and without the gulp plugin, and the bug was reproduced on both situations.

[Nickman87]

We also have this issue in 1.9.0 with the nth-child selectors, but it doesn't end there.
The following selector is also failing

&:not(:first-child) {
   border-left: none;
}

I don't see a specific test case being added for the not selector in the related pull request, will this also be fixed by your changes @DanPurdy ?

[DanPurdy]

@Nickman87 I'll check, it should be as it was just a case of missing a node type check.

[DanPurdy]

@Nickman87 I added your tests to the PR i can confirm the fix did fix this too and you should see it arrive in the next release which will hopefully be a patch release very soon

[Nickman87]

awesome! thanks