Change the login shell to zsh installed by Homebrew

chsh-to-brew-zsh.sh

#!/bin/bash
set -euo pipefail

echo "Checking zsh installed by Homebrew ..."
if version="$(brew list --versions zsh)"; then
  echo "Found: $version"
else
  echo "Could not find zsh installed by Homebrew"
  exit 1
fi

zsh_path="$(brew --prefix)/bin/zsh"
if [[ ! -x "$zsh_path" ]]; then
  echo "Could not find zsh executable"
  exit 1
fi

echo "Checking the login shell ..."
user_shell="$(dscl . -read "$HOME" UserShell | awk '{print $2}')"
if [[ "$user_shell" == "$zsh_path" ]]; then
  echo "The login shell is already $zsh_path"
else
  echo "Changing the login shell from $user_shell to $zsh_path ..."
  sudo dscl . -create "$HOME" UserShell "$zsh_path"
  echo "Checking the login shell again ..."
  dscl . -read "$HOME" UserShell
fi

echo "Done!"