CI: trigger per-commit workflow on PRs with ci:per-commit label

Author: dannywillems

.github/workflows/ci-per-commit.yaml

@@ -4,6 +4,10 @@ on:
   push:
     branches:
       - main
+  pull_request:
+    types: [opened, synchronize, reopened, labeled]
+    branches:
+      - main
 
 jobs:
   check-label:
@@ -12,24 +16,31 @@ jobs:
     outputs:
       has_label: ${{ steps.check.outputs.has_label }}
     steps:
-      - name: Find associated PR and check label
+      - name: Check for label
         id: check
         env:
           GH_TOKEN: ${{ github.token }}
         run: |
-          PRS=$(gh api \
-            "repos/${{ github.repository }}/commits/${{ github.sha }}/pulls" \
-            --jq '.[].number')
           HAS_LABEL="false"
-          for pr in $PRS; do
-            LABELS=$(gh api \
-              "repos/${{ github.repository }}/pulls/${pr}" \
-              --jq '.labels[].name')
-            if echo "$LABELS" | grep -q "^ci:per-commit$"; then
+          if [ "${{ github.event_name }}" = "pull_request" ]; then
+            LABELS='${{ toJSON(github.event.pull_request.labels.*.name) }}'
+            if echo "$LABELS" | grep -q "ci:per-commit"; then
               HAS_LABEL="true"
-              break
             fi
-          done
+          else
+            PRS=$(gh api \
+              "repos/${{ github.repository }}/commits/${{ github.sha }}/pulls" \
+              --jq '.[].number')
+            for pr in $PRS; do
+              LABELS=$(gh api \
+                "repos/${{ github.repository }}/pulls/${pr}" \
+                --jq '.labels[].name')
+              if echo "$LABELS" | grep -q "^ci:per-commit$"; then
+                HAS_LABEL="true"
+                break
+              fi
+            done
+          fi
           echo "has_label=${HAS_LABEL}" >> "$GITHUB_OUTPUT"
 
   ci: