fix: support CSS modules with :root pseudo-class only

[jsikorski]

Closes #26

[jcorkhill]

I still have this issue. As per #26, any SCSS file that contains a :root selector with no default classes fails to build with an Unterminated string literal error:

This is the stylesheet:

:root {
    box-sizing: border-box;
    font-size: calc(1vw + 0.6em);
}

@media (min-width: 50em) {
    :root {
        font-size: 1em;
    }
}

*,
*::before,
*::after {
    box-sizing: inherit;
}

body {
    height: 100%;
    width: 100%;
}

img { 
    max-width: 100%; 
}

If I append a .whatever to the end of the file and populate it with any arbitrary property (like border: none), it works and Webpack compiles successfully.

[jsikorski]

@JamieCorkhill
Do you still have the issue with the version I have proposed? I have just tried to compile the stylesheet you had provided and it seems to work.

Without changes from this PR error occurs but after applying this fix it seems to compile.

Maybe I have missed something and yout can provide some more information how to reproduce an issue?

[jcorkhill]

@jsikorski Sorry about that - I stupidly thought this had been merged. I saw the CI pass checks and I, for some reason, thought it had been merged. By applying the changes proposed in this PR the issue is indeed rectified. You can disregard my comment above.

[tswaters]

I hit this same issue, interesting workaround I found -- before (fails):

:root {
  --myvar: '#f00';
}

after (works)

/**/
:root {
  --myvar: '#f00';
}

Not sure why, but a blank block comment makes it work. Go figure.

[Obi-Dann]

Awesome work! Thanks for the PR, going to merge and release it shortly