Oh-my-zsh: alias rails, rake commands to generated spring binstubs on entering project's directory

chpwd_profiles.plugin.zsh

# put this file to $HOME/.oh-my-zsh/custom/plugins/chpwd_profiles
# and add plugin name to .zshrc: plugins=(... chpwd_profiles)

function chpwd_profiles() {
    local -x profile

    zstyle -s ":chpwd:profiles:${PWD}" profile profile || profile='default'
    if (( ${+functions[chpwd_profile_$profile]} )) ; then
        chpwd_profile_${profile}
    fi

    CHPWD_PROFILE="${profile}"
    return 0
}

chpwd_functions=( ${chpwd_functions} chpwd_profiles )

rails_spring_aliases.zsh

# put this file to $HOME/.oh-my-zsh/custom

# projects profile for projects directory and subdirectories where can be located rails projects
zstyle ":chpwd:profiles:$HOME/projects(|/|/*)" profile projects
# actually call the function
chpwd_profiles

# Executed when entering the profile
chpwd_profile_projects()
{
  alias_rails_binstub rails
  alias_rails_binstub rake
}

# Execute when leaving the profile
chpwd_leave_profile_projects()
{
  alias rails="rails"
  alias rake="rake"
}

function alias_rails_binstub ()
{
  if [ -f $PWD/bin/$1 ]; then
    alias $1="$PWD/bin/$1"
  else
    alias $1="$1"
  fi
}