pantry/projects/git-scm.org/git-shim

#!/bin/sh

set -e

# This function searches through the provided arguments
# to find the first non-option argument, which is assumed
# to be the git subcommand.
find_git_subcommand() {
  skip_next=0  # Flag to indicate if the next argument should be skipped.

  for arg in "$@"; do
    # If the skip_next flag is set, skip this argument.
    if [ "$skip_next" -eq 1 ]; then
      skip_next=0
      continue
    fi

    # Check for options that require skipping the next argument.
    case $arg in
      -C | --git-dir | --work-tree | --namespace | --super-prefix | --config-env | -c)
        skip_next=1  # The next argument is a value for these options.
        continue
        ;;
      -*)
        continue  # Skip other options that start with '-'.
        ;;
    esac

    # If we reach this point, it's likely the git subcommand.
    echo "$arg"
    return
  done
}

libexec="$(cd "$(dirname "$0")/.." && pwd)"/libexec

# extract the git subcommand
cmd=$(find_git_subcommand "$@")

_provides() {
  if foo="$(pkgx --provider git-"$cmd")"; then
    echo "$foo"
  else
    # syncing is slow but let’s be sure about it
    pkgx --sync --provider git-"$cmd"
  fi
}

_is_alias() {
  git config --get-regexp '^alias\.' | awk '{ print $1 }' | sed 's/alias\.//' | grep -qx "$cmd"
}

if [ -z "$cmd" ]; then
  exec "$libexec/git" "$@"
elif [ -x "$libexec/git-$cmd" ] && [ -f "$libexec/git-$cmd" ]; then
  exec "$libexec/git" "$@"
elif type "git-$cmd" >/dev/null 2>&1; then
  exec "$libexec/git" "$@"
elif ! _is_alias && command -v pkgx >/dev/null 2>&1 && pkg=$(_provides); then
  exec pkgx +"$pkg" "$libexec/git" "$@"
else
  exec "$libexec/git" "$@"
fi