agit.sh

# ‘alternate_git’:
#     > GIT_ALTERNATE_OBJECT_DIRECTORIES=../other_repo/.git/objects \ 
#        git cherry-pick $(git --git-dir=../other_repo/.git rev-parse --verify e9721)
# ... becomes ...
#     > agit ~[../other_repo] cherry-pick ~[e9721]
# 
# This is some seriously evil, hacky shit; but it works, unlike my original attempt with subshells.
# (Damn you, subshells.)
function agit() {
   env GIT_ALTERNATE_OBJECT_DIRECTORIES="$1/.git/objects" \
      =git ${${*:2}[@]} }

zsh_directory_name_functions=(${zsh_directory_name_functions[@]} uncommitish set_uncommitish_repo)
function uncommitish() { if [[ $1 == 'n' ]]; then
   if [[ -z "$UNCOMMITISH_REPO" ]]; then return 1; fi
   
   rev=$(git --git-dir="$UNCOMMITISH_REPO/.git" rev-parse --verify $2 2>/dev/null); st=$?
   if (( $st != 0 )); then return $st; fi
   
   reply=("$rev")
else return 1; fi }

function set_uncommitish_repo() { if [[ $1 == 'n' ]]; then
   export UNCOMMITISH_REPO="$2"
   reply=("$2")
else return 1; fi }

export zsh_directory_name_functions