Update PR-powershell-preview.yml

Author: TravisEz13

.github/workflows/PR-powershell-preview.yml

@@ -26,8 +26,39 @@ env:
   HOMEBREW_NO_INSTALL_CLEANUP: 1
 
 jobs:
+  changes:
+    if: startsWith(github.repository_owner, 'azure') || github.repository_owner == 'PowerShell'
+    name: Change Detection
+    runs-on: ubuntu-latest
+    # Required permissions
+    permissions:
+      pull-requests: read
+    # Set job outputs to values from filter step
+    outputs:
+      source: ${{ steps.filter.outputs.workflows }}
+    steps:
+      - name: checkout
+        uses: actions/checkout@v4
+
+        # For pull requests it's not necessary to checkout the code
+      - uses: dorny/paths-filter@de90cc6fb38fc0963ad72b210f1f284cd68cea36 # v3.2.0
+        id: filter
+        with:
+          list-files: json
+          filters: |
+            workflows:
+              - '.github/workflows/PR-powershell-lts.yml'
+              - 'Formula/powershell-lts.rb'
+
+      - name: Capture outputs
+        run: |
+          "workflows: ${{ steps.filter.outputs.workflows }}"
+        shell: pwsh
+      
   homebrew-formula-preview:
     timeout-minutes: 15
+    needs: changes
+    if: ${{ needs.changes.outputs.workflows == 'true' }}
     runs-on: macos-latest
     steps:
       - name: Checkout
@@ -49,3 +80,13 @@ jobs:
       - name: Install and Test Formula
         if: steps.filter.outputs.workflows == 'true'
         uses: ./.github/workflows/composite/installAndTest
+
+  ready_to_merge:
+    name: Preview ready to merge
+    needs:
+      - homebrew-formula-preview
+      - changes
+    if: always()
+    uses: PowerShell/compliance/.github/workflows/[email protected]
+    with:
+      needs_context: ${{ toJson(needs) }}