GitHub Code highlighting for React file with js extension

[ktalebian]

If you create a React file but save it with .js extension, then GitHub code highlighting breaks when it reaches a single quote in text. Saving the same file in .jsx works fine.

See example on this repo. Both file correct-highlighting.jsx and incorrect-highlighting.js have the same content. As you can, the .js has wrong syntax highlighting.

A solution is to add // vim: syntax=JSX to the top of the file, but this will get annoying really fast. Ideally, Linguist is intelligent to determine that the file is a React file and applies correct syntax.

[muescha]

same here:
https://github.com/keybase/client/blob/master/shared/nav.android.js#L113

[pchaigno]

We'd first have to add .js as a JSX extension for Linguist to be able to distinguish the two. Please see the guidelines to add support for a new extension to Linguist.