Add mcfunction language

[Arcensoth]

Description

This is an interesting case of "language" that originates from Minecraft server commands. The mcfunction file format is essentially a collection of server commands, one per line, with additional comment support and some unique runtime properties. The idea is simple, but the underlying command system is complex enough to warrant discussion about whether mcfunction should be considered a type of programming language. In any case: mcfunction files are both written and distributed in plain text, naturally giving way to open-source collaboration.

The search results listed in the checklist provide proof that mcfunction is being used across a reasonable number of repositories. There's even an open-source language server in development that includes extensive support for the mcfunction format.

I ran linguist dev on the language-mcfunction repository to get a breakdown of the results and to ensure my changes are functional.

Checklist:

• I am adding a new language.
  • The extension of the new language is used in hundreds of repositories on github.com.
    • Search results for each extension:
      • mcfunction:
        • Using suggested nothack
        • Using keyword tellraw
        • Using keyword setblock
        • Using keyword area_effect_cloud
  • I have included a real-world usage sample for all extensions added in this PR:
    • Sample source(s):
      • showcase.mcfunction from language-mcfunction
    • Sample license(s): MIT
  • I have included a syntax highlighting grammar
  • I have updated the heuristics to distinguish my language from others using the same extension.
    • Note: there are no other languages using the extension mcfunction

[Arcensoth]

Not sure why the build "errored" as opposed to failing or passing. Looks like it got part way through script/travis/before_install and then died for no apparent reason:

https://travis-ci.org/github/linguist/jobs/494397050#L1494

(Edit) On a second glance, I saw this:

https://travis-ci.org/github/linguist/jobs/494397050#L1213

Error updating vendor/grammars/language-mcfunction
error: pathspec 'vendor/grammars/language-mcfunction' did not match any file(s) known to git.

Did I miss something in the commit after the script/add-grammar step?

[pchaigno]

Yes, there's something missing. Did you use the provided script to add the grammar as per the contribution guidelines? Did you get any error message?

[Arcensoth]

Yes I followed the contribution guidelines thoroughly. I ran the script, and it was successful. I was able to run linguist and get a breakdown afterwards.

I cross-referenced with some other language PR's (here and here) and couldn't find any evidence of what's missing here.

[pchaigno]

Maybe you forgot to commit the submodule itself then. It should be under vendor/grammars/name of the grammar repo.

[Arcensoth]

Nice catch. But because language-mcfunction has received commits since I submitted the PR, I'm now facing a problem where the cached license is outdated. And apparently the language is not sorted correctly, but IIRC it was a script that added re-ordered it. (?) Anyway, I'll fix and try again.

[Arcensoth]

This may or may not be worth consideration, but there is an inconsistency between vendor/README.md and lib/linguist/languages.yml regarding how languages are sorted by name. As far as I can tell, the latter sorts upper-case first whereas the latter disregards case and mixes them together.

[pchaigno]

As far as I can tell, the latter sorts upper-case first whereas the latter disregards case and mixes them together.

Indeed. @Alhadis What do you think? Let's sort case-sensitively?

[pchaigno]

Thanks for your contribution and for the neat pull request @Arcensoth!

[Arcensoth]

Thanks for reviewing!

Small suggestion for CONTRIBUTING.md: add a step for Testing under the Adding an extension to a language and sections Adding a language. I think it could reduce the number of questions as a result of Travis errors, and also encourage contributors to submit cleaner PRs. :)

[Alhadis]

@Alhadis What do you think? Let's sort case-sensitively?

Sorry, I missed this. Yes, let's. Case-sensitive is strange and feels very machine-line.