workflows/check-by-name: Cancel on merge conflicts

.github/workflows/check-by-name.yml

@@ -8,8 +8,9 @@ on:
   # Using pull_request_target instead of pull_request avoids having to approve first time contributors
   pull_request_target
 
-# The tool doesn't need any permissions, it only outputs success or not based on the checkout
-permissions: {}
+permissions:
+  # We need this permission to cancel the workflow run if there's a merge conflict
+  actions: write
 
 jobs:
   check:
@@ -62,7 +63,14 @@ jobs:
           if [[ "$mergeable" == "true" ]]; then
             echo "The PR can be merged, checking the merge commit $mergedSha"
           else
-            echo "The PR cannot be merged, it has a merge conflict"
+            echo "The PR cannot be merged, it has a merge conflict, cancelling the workflow.."
+            gh api \
+              --method POST \
+              -H "Accept: application/vnd.github+json" \
+              -H "X-GitHub-Api-Version: 2022-11-28" \
+              /repos/"$GITHUB_REPOSITORY"/actions/runs/"$GITHUB_RUN_ID"/cancel
+            sleep 60
+            # If it's still not canceled after a minute, something probably went wrong, just exit
             exit 1
           fi
           echo "mergedSha=$mergedSha" >> "$GITHUB_ENV"