Diagnose why yarn installed package returns "command not found" on CLI

yarn-doctor-command-not-found.sh

#!/bin/bash

if [ ! -f "package.json" ]; then
  echo "No package.json. Run this at your project root."
  exit 1
fi

echo -n "Command not found: "
read command

if [ ! -d "./node_modules/.bin" ]; then
  echo "Missing ./node_modules/.bin. Run 'yarn install'."
  exit 1
fi

if [ ! -f "./node_modules/.bin/$command" ]; then
  echo "Missing command $command. Install with 'yarn add <package>'."
  exit 1
fi

if [[ ":$PATH:" != *":$(yarn global bin):"* ]]; then
  echo "Yarn's bin not in PATH. Add with 'export PATH=\"$(yarn global bin):\$PATH\"' (probably use \$HOME) in .bashrc or .zshrc."
fi

if ! grep -q "\"$command\"" "package.json"; then
  echo "Command $command not in scripts. Add it or run with 'yarn run <command>'."
fi

echo "Looks correct. Check package documentation or reinstall with 'yarn add <package>'."