clusterctl: Support autocompletion for the fish shell

[guettli]

What would you like to be added (User Story)?

As an operator, if would like to have shell autocompletion for clusterctl because this is convenient.

Detailed Description

In bash (configured via docs about completion) clusterctl get kubeTABTAB will autocomplete to clusterctl get kubeconfig.

It would be nice to have this for the fish shell, too.

According to the source fish is already suported. But I guess it is not provided via homebrew.

Here my fish completions:

❯ find .linuxbrew/share/fish/
.linuxbrew/share/fish/
.linuxbrew/share/fish/vendor_completions.d
.linuxbrew/share/fish/vendor_completions.d/atuin.fish
.linuxbrew/share/fish/vendor_completions.d/delta.fish
.linuxbrew/share/fish/vendor_completions.d/hcloud.fish
.linuxbrew/share/fish/vendor_completions.d/k9s.fish
.linuxbrew/share/fish/vendor_completions.d/golangci-lint.fish
.linuxbrew/share/fish/vendor_completions.d/kubectl.fish
.linuxbrew/share/fish/vendor_completions.d/chezmoi.fish
.linuxbrew/share/fish/vendor_completions.d/oras.fish
.linuxbrew/share/fish/vendor_completions.d/rg.fish
.linuxbrew/share/fish/vendor_completions.d/gh.fish
.linuxbrew/share/fish/vendor_completions.d/yq.fish
.linuxbrew/share/fish/vendor_completions.d/starship.fish
.linuxbrew/share/fish/vendor_completions.d/helm.fish
.linuxbrew/share/fish/vendor_completions.d/tilt.fish
.linuxbrew/share/fish/vendor_completions.d/fd.fish
.linuxbrew/share/fish/vendor_completions.d/stern.fish
.linuxbrew/share/fish/vendor_completions.d/kind.fish
.linuxbrew/share/fish/vendor_completions.d/brew.fish
.linuxbrew/share/fish/vendor_conf.d
.linuxbrew/share/fish/vendor_conf.d/direnv.fish

Anything else you would like to add?

I can have a look at this, too, and create a PR. Just tell me.

Label(s) to be applied

/kind feature

/area clusterctl

[chrischdi]

I can have a look at this, too, and create a PR. Just tell me.

@guettli : feel free to assign to yourself and go ahead.

[kranurag7]

this was done here via this patch #9950 I am using clusterctl 1.7.2 version and the completion is there. (missing in 1.6 series as it was not cherry-picked)

You can use fish completion using clusterctl completion fish | source

To have completion for every shell environment, you'll have to save it on your ~/.config/fish/config.fish you can use the following:

if command -v clusterctl &> /dev/null
    clusterctl completion fish | source
end

[kranurag7]

I created a patch in homebrew repo to have completion enabled by default for fish shell as well when you use brew install clusterctl

ref: Homebrew/homebrew-core#174030

[guettli]

@kranurag7 thank you very much. After install clusterctl via brew again, it worked out of the box. No need to configure autocomplete manually.

❯ find /home/linuxbrew/.linuxbrew/share/fish/| grep clusterctl
/home/linuxbrew/.linuxbrew/share/fish/vendor_completions.d/clusterctl.fish

issue is solved.

I use that in my config.fish:

...
if status is-interactive
    # Commands to run in interactive sessions can go here


    /home/linuxbrew/.linuxbrew/bin/brew shellenv | source

    # Autocomplete for commands installed via brew.
    eval (/home/linuxbrew/.linuxbrew/bin/brew shellenv)
    if test -d (brew --prefix)"/share/fish/completions"
        set -p fish_complete_path (brew --prefix)/share/fish/completions
    end

    if test -d (brew --prefix)"/share/fish/vendor_completions.d"
        set -p fish_complete_path (brew --prefix)/share/fish/vendor_completions.d
    end
...

This way, the autocomplete gets installed automatically (if provided by the application installed via brew).

[sbueringer]

Nice! Thx @kranurag7