docs(core): add script to check if Vercel build should be ignored or not (#5489)

scripts/vercel/ignore-build.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+
+# This script is used in Vercel to determine whether to continue the build or not for nx-dev.
+# Exits with 0 if the build should be skipped, and exits with 1 to continue.
+
+APP=$1
+NX_VERSION=$(node -e "console.log(require('./package.json').devDependencies['@nrwl/workspace'])")
+
+# Need the workspace in order to run affected
+yarn add -D @nrwl/workspace@$NX_VERSION --prefer-offline
+
+# We don't have a good way to check from base due to Vercel's shallow clone
+# TODO: Fix this once we figure out a better solution
+npx nx affected:apps --plain --base HEAD~1 --head HEAD | grep $APP -q
+
+STATUS=$?
+
+if [ $STATUS -eq 1 ]; then
+  echo "🛑 - Build cancelled"
+  exit 0
+elif [ $STATUS -eq 0 ]; then
+  echo "✅ - Build can proceed"
+  exit 1
+fi
+
+# Ignore all production deployments since this should be a manual promotion
+if [ $VERCEL_GIT_COMMIT_REF == "master" ]; then
+  echo "🛑 - Build cancelled"
+  exit 0
+fi