Add a method for installing fish function files

[zachwhaley]

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Fish shell allows third-party software vendors to put their own function files in a directory for their software.
For brew installed Fish shell, this is /usr/local/share/fish/vendor_functions.d

[bfontaine]

typo: function

[bfontaine]

Shouldn’t that be plural like fish_functions?

[zachwhaley]

I can change this, but it seemed like the convention was singular.

[zachwhaley]

Thanks @bfontaine for the feedback!

Do y'all want me to amend this commit, or create new ones?

[MikeMcQuaid]

What software installs Fish functions and what are they used for? Thanks!

[zachwhaley]

@MikeMcQuaid Fish shell plugins and frameworks probably use Fish functions, (e.g. oh-my-fish), and they are basically command line commands for the Fish shell.

My little project uses a Fish function to override and enhance a command.

[MikeMcQuaid]

My little project uses a Fish function to override and enhance a command.

@zachwhaley To make a core change we'll probably want a few example projects rather than just your personal one. Could you link to a few? Thanks!

[zachwhaley]

@MikeMcQuaid see my comment on PR #1616

Thanks!

[zachwhaley]

Here are a couple packages that are installing a fish script to some location and asking the user to source that file, when instead they could install that script to fish/vendor_functions.d and it would be autoloaded when the user runs it.

• autojump
• homeshick

[MikeMcQuaid]

Perfect, thanks for explaining so well. Merging this and would ❤️ PRs for those formulae to use this after that.