Automatically switch node version using fnm based on the required value in package.json

nodeVersionSwitch.sh

#!/usr/bin/env bash

# Place this script in the same directory as your package.json file.
# Uncomment and add the section below to your .zshrc
# SECTION BEGIN
# # nodeVersionSwitch.sh script https://gist.github.com/mrtysn/ff2a68c27b2be908c4f8188052d7d728
# # fnm node version manager https://github.com/Schniz/fnm#zsh
# eval "$(fnm env --use-on-cd)"
# if [ -f "./package.json" ] && [ -f "./nodeVersionSwitch.sh" ]; then
#   bash "./nodeVersionSwitch.sh"
# fi
# SECTION END

NODE_REQUIRED=$(node -p "require('./package.json').engines.node")
echo "Required node version in ./package.json is $NODE_REQUIRED"

if [[ "$NODE_REQUIRED" =~ "~"|"^" ]] ; then
  NODE_REQUIRED="v${NODE_REQUIRED:1}"
  N_DOT=$(grep -o "\." <<< "$NODE_REQUIRED" | wc -l)
  if (( $N_DOT < 2 )) ; then
    NODE_REQUIRED="$NODE_REQUIRED.0"
  fi
fi

echo "Trying to switch to node version $NODE_REQUIRED using fnm. If this fails, you can manually switch to the required version using 'fnm use $NODE_REQUIRED'"
fnm use $NODE_REQUIRED
echo "Done. node version is now $(node -v)"