Mattermost-server: [Help Wanted] [MM-13951] Allow "C" to be used for code block syntax highlighting

[esethna]

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Notes: Jira ticket

Original report: https://github.com/mattermost/mattermost-server/issues/10221

Summary
The C keyword does not work for code block syntax highlighting.

Steps to reproduce
Tested on server version 5.7.0 with desktop client version 4.2.0.

Expected behavior
Correct syntax highlighting on code blocks when the C or c keyword is used.

Observed behavior
While the cpp keyword does apply syntax highlighting,
it shows C/C++ as the language, and from that i would expect C to be a valid keyword to use this.

Possible fixes
highlight.js "supports" C as an alias (https://github.com/highlightjs/highlight.js/blob/master/src/languages/cpp.js#L98) for C++ but this is not used (https://github.com/mattermost/mattermost-webapp/blob/master/utils/syntax_highlighting.jsx#L72).

[manland]

I'm work on this!

@hanzei It's possible to add sh as bash alias ? Every time I need to edit my previous post...

[crspeller]

@manland Go for it. I think that's useful.