centralized skip_build script with real working git commands

scripts/skip-build-base.mjs

@@ -0,0 +1,60 @@
+import process from 'node:process'
+import { execSync } from 'child_process'
+
+export const shouldSkipBuild = (siteName, checkFolders = '../shared .') => {
+  console.log('Skip build script version 1.0.0')
+
+  // Do not block production builds
+  if (process.env.VERCEL_ENV === 'production') {
+    console.log('✅ - Production build - Proceed to build')
+    process.exit(1)
+  }
+
+  // Do not build dependabot PRs
+  if (process.env.VERCEL_GIT_COMMIT_AUTHOR_LOGIN === 'dependabot[bot]') {
+    console.log('🛑 - Dependabot PR - Do not build')
+    process.exit(0)
+  }
+
+  const branch = process.env.VERCEL_GIT_COMMIT_REF
+  // Always build develop branch
+  if (branch === 'develop') {
+    console.log('✅ - develop build - Proceed to build')
+    process.exit(1)
+  }
+
+  // Only build pull requests that made changes to the given site
+  if (process.env.VERCEL_GIT_PULL_REQUEST_ID) {
+    try {
+      // we need to add the origin so that we can compare to develop
+      execSync(
+        `git remote add origin https://github.com/${process.env.VERCEL_GIT_REPO_OWNER}/${process.env.VERCEL_GIT_REPO_SLUG}.git`
+      )
+      // we need to fetch develop in order to get the merge base
+      execSync(`git fetch origin develop:develop --depth=5`)
+      // if depth 5 wasn't enough, keep deepening until we find the merge base
+      execSync(
+        `until git merge-base develop HEAD > /dev/null; do git fetch origin develop:develop --deepen=1; done`
+      )
+
+      // now check for changes
+      const changes = execSync(
+        `git diff --name-only $(git merge-base develop HEAD) HEAD -- ${checkFolders}`
+      ).toString()
+      if (changes) {
+        console.log(`✅ - ${siteName} Pull Request - Proceed to build`)
+        process.exit(1)
+      }
+    } catch {
+      // just don't error out
+    }
+
+    console.log(`🛑 - Pull Request made no changes to ${siteName} - Do not build`)
+    process.exit(0)
+  }
+
+  console.log('🛑 - Unhandled case - Do not build')
+  console.log(`  VERCEL_GIT_COMMIT_AUTHOR_LOGIN: ${process.env.VERCEL_GIT_COMMIT_AUTHOR_LOGIN}`)
+  console.log(`  VERCEL_GIT_COMMIT_REF: ${branch}`)
+  process.exit(0)
+}