Zsh – Set Autocompletion Rules for Second Argument

autocompletegitzsh

I have a custom Zsh function g:

function g() {
  # Handle arguments [...]
}

Within it, I handle short arguments that execute Git commands. For example:

g ls # Executes git ls-files ...
g g  # Executes git grep ...

I need to be able to set the autocompletion rules to Git's rules for the short arguments but I am unsure of how to do this.

For example, I need g ls <TAB> to tab-complete the rules for git ls-files <TAB> which would give me the arguments for git ls-files:

$ g ls --<TAB>
--abbrev                 -- set minimum SHA1 display-length
--cached                 -- show cached files in output
--deleted                -- show deleted files in output
# Etc...

This is not simply setting g to autocomplete for git since I'm mapping my custom short commands to the Git commands.

Best Answer

I found /usr/share/zsh/functions/Completion/Unix/_git which had some tips for aliases like this and ended up defining these functions for the aliases:

_git-ls () {
  # Just return the _git-ls-files autocomplete function
  _git-ls-files
}

Then, I did a straight compdef g=git. The autocomplete system will see that you are running, for example, g ls and use the _git-ls autocomplete function.

Thanks to user67060 for steering me in the right direction.

Related Solutions

How to get the shell functions to make use of existing autocompletion in zsh

To request that a command be completed like another command that is already known to the completion system, you can use the compdef my_command=known_command form of compdef.

compdef s=ssh
compdef {cxterm,uxterm,xterm-color}=xterm

Under the hood, this is basically equivalent to _comps[s]=$_comps[ssh].

Some completion commands apply to a family of functions and read the first word of the command line to determine which particular command to complete. For example, the commands ssh, scp, sftp and a few more are all completed by the function _ssh. In that case, you need to tell the completion function which “service” your function is like (by default, the service is the executable name, here your function's name).

_s () {
  local service=ssh
  _ssh "$@"
}
compdef _s s

Bash – Change Starting Directory for Remote Autocompletion

Edit: Sliced it up some more.

You might find this useful, from Debian Administration: An introduction to bash completion.

Complete script: /some/location/my_ssh_autocomplete_script (only meant as a short starter):

#!/bin/bash

_get_rsync_file_list()
{
    # For test:
    #local -a flist=("foo" "bar")
    #printf "%s " "${flist[@]}"
    # Or:
    ls /tmp

    # For live something in direction of:
    #ssh user@host 'ls /path/to/dir' <-- but not ls for other then dirty testing.
}

_GetOptSSH()
{
    local cur

    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"

    case "$cur" in
    -*)
        COMPREPLY=( $( compgen -W '-h --help' -- "$cur" ) );;
    *)
        # This could be done nicer I guess:
        COMPREPLY=( $( compgen -W "$(_get_rsync_file_list)" -- "$cur" ) );;
    esac

    return 0
}

Download script /some/location/my_ssh_download_script:

#!/bin/bash

server="myserver"
path="/home/pierre/downloads"

download_from_myserver() {
    for file; do
        rsync "$server:$path/$file"
    done
}

case "$1" in
    "-h"|"--help")
        echo "Download files from '$server', path: '$path'" >&2
        exit 0;;
esac

download_from_myserver "$@"

In .bash_aliases:

alias download_from_myserver='/some/location/my_ssh_download_script'

In .bash_completion:

# Source complete script:
if . "/some/location/my_ssh_autocomplete_script" >/dev/null 2>&1; then
    # Add complete function to download alias:
    complete -F _GetOptSSH download_from_myserver
fi

Best Answer

Related Solutions

How to get the shell functions to make use of existing autocompletion in zsh

Bash – Change Starting Directory for Remote Autocompletion

Related Question