[cherry-pick] Allow cherry-pick bot PRs in engineering system changes check (#311505)

Allow cherry-pick bot PRs in engineering system changes check (#311475)

* Allow cherry-pick bot PRs in engineering system changes check

Add an exception for PRs created by vs-code-engineering[bot] whose title
starts with [cherry-pick] and that carry the cherry-pick-artifact label.



* Fetch cherry-pick-artifact label via API at runtime

The label is applied ~2s after PR creation, so the webhook payload may
not include it. Fetch current labels from the API instead, gated behind
cheap event-payload checks to avoid extra API calls on unrelated PRs.



* Add label retry loop and consolidate guard expressions

Retry the cherry-pick-artifact label check up to 3 times (2s apart) to
handle the ~2s delay between PR creation and label application.

Consolidate the repeated exception guards into a single 'allowed' step
with a 'blocked' output, simplifying downstream conditions.



---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: benvillalobos

.github/workflows/no-engineering-system-changes.yml

@@ -88,30 +88,62 @@ jobs:
           fi
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - name: Allow cherry-pick bot PRs
+        id: cherry_pick_exception
+        if: ${{ steps.engineering_systems_check.outputs.engineering_systems_modified == 'true' && steps.bot_field_exception.outputs.allowed != 'true' && github.event.pull_request.user.login == 'vs-code-engineering[bot]' && startsWith(github.event.pull_request.title, '[cherry-pick]') }}
+        run: |
+          # The label is applied ~2s after PR creation, so the webhook payload
+          # may not include it yet. Fetch current labels from the API with retries.
+          for attempt in 1 2 3; do
+            if gh api repos/${{ github.repository }}/issues/${{ github.event.pull_request.number }}/labels --jq '.[].name' | grep -qx 'cherry-pick-artifact'; then
+              echo "Cherry-pick PR by vs-code-engineering bot with cherry-pick-artifact label — allowing"
+              echo "allowed=true" >> $GITHUB_OUTPUT
+              exit 0
+            fi
+            if [ "$attempt" -lt 3 ]; then
+              echo "cherry-pick-artifact label not present yet (attempt $attempt/3); retrying in 2s"
+              sleep 2
+            fi
+          done
+          echo "Cherry-pick PR by bot but missing cherry-pick-artifact label after retries — not allowed"
+          echo "allowed=false" >> $GITHUB_OUTPUT
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - name: Determine if engineering system changes are allowed
+        id: allowed
+        if: ${{ steps.engineering_systems_check.outputs.engineering_systems_modified == 'true' }}
+        run: |
+          if [[ "${{ steps.bot_field_exception.outputs.allowed }}" == "true" || "${{ steps.cherry_pick_exception.outputs.allowed }}" == "true" ]]; then
+            echo "Engineering system changes are allowed by an exception"
+            echo "blocked=false" >> $GITHUB_OUTPUT
+          else
+            echo "No exception applies — enforcing restrictions"
+            echo "blocked=true" >> $GITHUB_OUTPUT
+          fi
       - name: Prevent Copilot from modifying engineering systems
-        if: ${{ steps.engineering_systems_check.outputs.engineering_systems_modified == 'true' && steps.bot_field_exception.outputs.allowed != 'true' && github.event.pull_request.user.login == 'Copilot' }}
+        if: ${{ steps.allowed.outputs.blocked == 'true' && github.event.pull_request.user.login == 'Copilot' }}
         run: |
           echo "Copilot is not allowed to modify .github/workflows, build folder files, or package.json files."
           echo "If you need to update engineering systems, please do so manually or through authorized means."
           exit 1
       - uses: octokit/request-action@b91aabaa861c777dcdb14e2387e30eddf04619ae # v3.0.0
         id: get_permissions
-        if: ${{ steps.engineering_systems_check.outputs.engineering_systems_modified == 'true' && steps.bot_field_exception.outputs.allowed != 'true' && github.event.pull_request.user.login != 'Copilot' }}
+        if: ${{ steps.allowed.outputs.blocked == 'true' && github.event.pull_request.user.login != 'Copilot' }}
         with:
           route: GET /repos/microsoft/vscode/collaborators/${{ github.event.pull_request.user.login }}/permission
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       - name: Set control output variable
         id: control
-        if: ${{ steps.engineering_systems_check.outputs.engineering_systems_modified == 'true' && steps.bot_field_exception.outputs.allowed != 'true' && github.event.pull_request.user.login != 'Copilot' }}
+        if: ${{ steps.allowed.outputs.blocked == 'true' && github.event.pull_request.user.login != 'Copilot' }}
         run: |
           echo "user: ${{ github.event.pull_request.user.login }}"
           echo "role: ${{ fromJson(steps.get_permissions.outputs.data).permission }}"
           echo "is dependabot: ${{ github.event.pull_request.user.login == 'dependabot[bot]' }}"
           echo "should_run: ${{ !contains(fromJson('["admin", "maintain", "write"]'), fromJson(steps.get_permissions.outputs.data).permission) }}"
           echo "should_run=${{ !contains(fromJson('["admin", "maintain", "write"]'), fromJson(steps.get_permissions.outputs.data).permission) && github.event.pull_request.user.login != 'dependabot[bot]' }}" >> $GITHUB_OUTPUT
       - name: Check for engineering system changes
-        if: ${{ steps.engineering_systems_check.outputs.engineering_systems_modified == 'true' && steps.bot_field_exception.outputs.allowed != 'true' && steps.control.outputs.should_run == 'true' }}
+        if: ${{ steps.allowed.outputs.blocked == 'true' && steps.control.outputs.should_run == 'true' }}
         run: |
           echo "Changes to .github/workflows/, build/ folder files, or package.json files aren't allowed in PRs."
           exit 1