Add tutorial for fish in execute_commands_on_host.md

[ghost]

Add fish because i like fish

[nathanchance]

The official fish documentation recommends that functions go in ~/.config/fish/functions and it should be the name of the function:

~/.config/fish/functions/fish_command_not_found.fish

I might reword the sentence as:

Place this snippet in a new fish configuration file (~/.config/fish/functions/fish_command_not_found.fish)

[ghost]

sure, go ahead. can you modify my PR directly?

i was deciding whether I should change to ~/.config/fish/functions, but because my own testing was done with ~/.config/fish/conf.d I waited until I get access to my Linux laptop again so I can test.

[nathanchance]

I think this function is a little bit more readable if you:

• reversed the logic of the container check
• used more idiomatic fish, such as or and command -q

I think the exit 127 should be return 127 since it is a function.

function fish_command_not_found
    # "In a container" check
    if test -e /run/.containerenv; or test -e /.dockerenv
        if command -q flatpak-spawn
            flatpak-spawn --host $argv
        else if command -q host-exec
            host-exec "$argv"
        else
            return 127
        end
    else
        __fish_default_command_not_found_handler "$argv"
    end
end

[ghost]

Does return 127 work? I don't have my Linux laptop nearby so I can't confirm.

I was about to change exit 127 to __fish_default_command_not_found_handler "$argv" because yesterday I found that exit 127 would cause shell to exit directly (Try this: Run invalid command within a distrobox that doesn't have flatpak-spawn or host-exec) and I only changed one of them (there're two exit 127 in the original function)

This function is mostly based on the original function for bash/zsh, I only modified it so it can run on fish, didn't notice the readability issue. I think you can modify my PR right?

[ghost]

Re-request review button is broken.
@nathanchance

[nathanchance]

Thanks! This looks fine to me from a fish perspective. I cannot test it though, as I don't use those commands. Hopefully I didn't give you the wrong impression but I am not the owner of this repo (@89luca89 is) so you'll need to wait for him to merge it.

[89luca89]

@thjderjktyrjkt thanks a lot for the contribution!
and thanks @nathanchance for the help 😄