#!/bin/sh
# Run yarn install when switching branches (if yarn.lock changed)

# $3 is 1 for branch checkout, 0 for file checkout
if [ "$3" != "1" ]; then
  exit 0
fi

# Check if yarn.lock changed between the old and new HEAD
if git diff --name-only "$1" "$2" | grep -q "^yarn.lock$"; then
  echo "yarn.lock changed — running yarn install..."
  yarn install
fi