Bash script for managing PHP versions on macOS (using Homebrew)

mphp

#!/usr/bin/env bash
#
# Copyright (c) 2016 Matthew Loberg
# Distributed under the MIT License (http://opensource.org/licenses/MIT)
#
# ==========================
# Manage PHP (uses Homebrew)
# ==========================
#
# Commands:
#   mphp list
#   mphp current
#   mphp switch [phpversion]
#   mphp install [phpversion]
#   mphp upgrade [phpversion]
#
# Requirements:
#   Homebrew (http://brew.sh/)
#   Homebrew PHP (https://github.com/Homebrew/homebrew-php)

currentversion=$(php -r "error_reporting(0); echo str_replace('.', '', substr(phpversion(), 0, 3));")

abort() {
  (>&2 printf "\033[0;31m$1\033[0m\n")
  exit 1
}

list() {
  for package in $(brew list | grep 'php[0-9]\{2\}$'); do
    version="${package:3}"
    extra=""

    if [ "${version}" == "${currentversion}" ]; then
      extra="(current)"
    fi

    echo "* ${version} ${extra}"
  done
}

switch() {
  local newversion="$1"
  local package="php${newversion}"

  if ! $(brew list ${package} &>/dev/null); then
		abort "PHP version ${newversion} was not found."
	fi

	brew unlink "php${currentversion}" &>/dev/null
	brew link "${package}" &>/dev/null

  echo "Switched to PHP ${newversion}"
}

install() {
  local newversion="$1"
  local package="php${newversion}"

  if ! $(brew list ${package} &>/dev/null); then
    brew install "${package}"
  fi

  echo "Installed PHP ${newversion}"
}

upgrade() {
  local newversion="$1"

  switch "${newversion}"
  brew upgrade "${newversion}"
  switch "${currentversion}"
}

if [ "$1" == "list" ]; then
  list
  exit
elif [ "$1" == "current" ]; then
  echo "${currentversion}"
  exit
fi

if [ $# -ne 2 ]; then
	abort "Usage: $(basename "${0}") [command] [phpversion]"
fi

if [ "$1" == "switch" ]; then
	switch "$2"
elif [ "$1" == "install" ]; then
	install "$2"
elif [ "$1" == "upgrade" ]; then
	upgrade "$2"
else
	abort 'Valid commands are: "switch", "install", or "upgrade".'
fi