Rebuild with new commit --allow-empty on rector-src when rector-src is tagged on trigger Rebuild

.github/workflows/dispatch_build_scoped_rector.yaml

@@ -0,0 +1,49 @@
+# github action that rebuilds https://github.com/rectorphp/rector
+# with the freshly merged rector-downgrade-php main
+name: Dispatch Build Scoped Rector
+
+on:
+    push:
+        branches:
+            - main
+    workflow_dispatch: null
+
+jobs:
+    dispatch_build_scoped_rector:
+        # only for this repository, not forks
+        if: github.repository == 'rectorphp/rector-downgrade-php'
+
+        runs-on: ubuntu-latest
+        timeout-minutes: 10
+
+        steps:
+            -
+                name: "Wait 20 seconds after push"
+                run: sleep 20
+
+            -
+                name: "Check whether rector-src main is a release tag commit"
+                env:
+                    ACCESS_TOKEN: ${{ secrets.ACCESS_TOKEN }}
+                    GH_TOKEN: ${{ secrets.ACCESS_TOKEN }}
+                run: |
+                    RECTOR_SRC="https://github.com/rectorphp/rector-src.git"
+
+                    MAIN_SHA=$(git ls-remote $RECTOR_SRC refs/heads/main | cut -f1)
+                    if [ -z "$MAIN_SHA" ]; then
+                        echo "Could not resolve rector-src main"
+                        exit 1
+                    fi
+
+                    # lightweight tags are listed with the commit itself, annotated ones with a "^{}" line
+                    if git ls-remote --tags $RECTOR_SRC | grep -q "^${MAIN_SHA}"; then
+                        echo "rector-src main $MAIN_SHA is tagged, creating a rebuild commit"
+                        git clone --depth 1 --branch main "https://x-access-token:${ACCESS_TOKEN}@github.com/rectorphp/rector-src.git" rector-src
+                        cd rector-src
+                        git config user.name "TomasVotruba"
+                        git config user.email "tomas.vot@gmail.com"
+                        git commit --allow-empty -m 'Rebuild' -a
+                        git push origin main
+                    else
+                        gh workflow run build_scoped_rector.yaml --repo rectorphp/rector-src --ref main
+                    fi