Add brand prefixes for fontawesome icons

[apreshill]

Noticed some of your icons in the upper navbar were broken, this one bit me too!

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Codecov Report

Merging #46 (80c3391) into master (f2edaf0) will not change coverage.
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[gadenbuie]

Thanks! I've seen this in more than a few places and have been meaning to dig into it!

[cderv]

No need to dig it more, this is a known issue rstudio/rmarkdown#1991 and there is already a PR that I think solves it.

Sorry for the trouble 😄

[gadenbuie]

Thanks @cderv (for telling me after I went and updated 6 other repos 😜)! Seriously though, am I reading that issue right that you'll make FA4 work but that using the FA5 prefixes is probably the safest option in the future?

[cderv]

Seriously though, am I reading that issue right that you'll make FA4 work but that using the FA5 prefixes is probably the safest option in the future?

The story is that

• rmarkdown did upgrade to FA5 (Add Font awesome 5.0.13 support rstudio/rmarkdown#1340)
• but the new prefixes where not supported in navbar, so I extended support in handle new prefix in fontawesome 5 rstudio/rmarkdown#1967 making the new prefix fas the default
• But this broke some stuff (the issue you read) that where working without any prefix because it was added but rmarkdown. Hence the last PR (Insure fontawesome V4 compatibility in navbar rstudio/rmarkdown#1994)

So FA4 will work without the prefix changes for what is included in the shims file for compatibility (https://github.com/rstudio/rmarkdown/blob/master/inst/rmd/h/fontawesome/css/v4-shims.css following https://fontawesome.com/how-to-use/on-the-web/setup/upgrading-from-version-4#manually).
So rmarkdown will do as before and add fa prefix for you. This will work for everything that works with the compatibility layer, but it is best to provide the correct prefix to select icons now.

Does it seem not right to you ?

We could try being more clever and try to decide the right prefix, but it seemed a bit too much. If you want to dicuss it, I'll be happy to.

[cderv]

In fact, I looked into how shiny handles it and they maintain a list of fontawesome brand icon. When one is detected the fab prefix is used.

I think this can follow up this path to make easily updated and so that just the name of the icon can be passed. No prefix needed then.

Thanks for challenging this !