Simple git completion (branches only, no context)

simple_git_completion.bash

__simple_upsearch() {
  if [[ -e $1 ]]; then
    [[ $PWD == / ]] \
      && printf '/%s' "$1" \
      || printf '%s/%s' "$PWD" "$1"

    return 0
  fi

  [[ $PWD == / ]] && return 1

  cd ..
  __simple_upsearch "$1"
}

__simple_git_complete_options() {
  (
  gitloc=$(__simple_upsearch .git)

  options=()

  # Add local branch names
  cd "$gitloc/refs/heads"
  options+=(*)

  # Get remote names
  cd "$gitloc/refs/remotes"
  for r in *; do
    # Add bare remote branch names
    cd "$r"
    options+=(*)

    # Add prefixed remote branch names
    cd ..
    options+=("$r"/*)
  done

  printf '%s\n' "${options[@]}" | sort | uniq
  )
}

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

  IFS=$'\n'
  options=($(__simple_git_complete_options))
  unset IFS

  # Handle leading colon
  if [[ ${cur:0:1} == : ]]; then
    cur="${cur:1}"
  fi

  # Handle leading caret
  if [[ ${cur:0:1} == ^ ]]; then
    IFS=$'\n'
    options=($(printf '^%s\n' "${options[@]}"))
    unset IFS
  fi

  # Determine if the current word is a revision range (e.g. master...feature,
  # master..feature)
  symmetric=$(grep -o '\.\.\(\.\)\?' <<< "$cur")

  if [[ -n $symmetric ]]; then
    IFS="$symmetric" read -ra bs <<< "$cur"

    IFS=$'\n'
    options=($(printf "${bs[0]}${symmetric}"'%s\n' "${options[@]}"))
    unset IFS
  fi

  COMPREPLY=($(compgen -W "${options[*]}" "$cur"))
}

complete -o bashdefault -o default -o nospace -F __simple_git_complete git

Why?

The full git completion file is kind of overkill and adds to bash's boot time. I only ever really want branch name completion so I wanted a light-weight script just for that.

Drawbacks

• Was designed primarily with completion of branch names in mind. As such, completion options do not depend on context.
• Assumes branch/remote names have no spaces in them (I believe this must be true anyway so maybe it's not actually a drawback)

Advantages

• Faster than git-completion.bash