My take on directory-specific environments on the command-line

autoenv

#!/usr/bin/env zsh
#
# USAGE: autoenv [action]
#
#  Actions:
#   up      (aliased to u)
#   down    (aliased to d)
#

error() { echo "$@" 1>&2 }

init() {
  unset -f autoenv-up autoenv-down > /dev/null 2>&1

  local red_color="\e[31m"
  local green_color="\e[32m"
  local yellow_color="\e[33m"
  local no_color="\e[0m"

  if (( $# > 1 )); then
    error "${red_color}ERROR: Too many arguments!${no_color}"
    return 1
  fi

  local autoenv_action="up"

  [[ -n "$1" ]] && autoenv_action="$1"

  if [[ ! -f ".env" ]]; then
    error "${red_color}ERROR: Could not find .env file!${no_color}"
    return 1
  fi

  source .env > /dev/null 2>&1

  if ! type autoenv-up > /dev/null 2>&1; then
    error "${red_color}ERROR: Invalid syntax in the .env file!${no_color}"
    error "${yellow_color}The .env file must define \`autoenv-up\` and \`autoenv-down\` functions!${no_color}"
    return 1
  fi

  case "$autoenv_action" in
    u|up)
      autoenv-up

      echo "${green_color}SUCCESS: autoenv up!${no_color}"
      ;;
    d|down)
      autoenv-down

      echo "${green_color}SUCCESS: autoenv down!${no_color}"
      ;;
    *)
      error "${red_color}ERROR: Invalid autoenv action: ${1}${no_color}"
      return 1
  esac

  unset -f autoenv-up autoenv-down > /dev/null 2>&1
}

init $@

cd.zsh

# Example `cd` wrapper
cd() {
  local directory

  if (( $# -eq 0 )); then
    directory="$HOME"
  elif [[ "$1" == "-" ]]; then
    directory="$OLDPWD"
  else
    directory="$1"
  fi

  if [[ -f $directory ]]; then
    echo "$fg[red]$directory is a file!$reset_color"
    return 1
  fi

  directory="$(realpath $directory)"

  if [[ "$(pwd)" != "$directory" && ! "$(pwd)" =~ "$directory" ]]; then
    autoenv down > /dev/null 2>&1
  fi

  builtin cd $directory > /dev/null

  autoenv up 2> /dev/null || true
}