Attempt to fix commit-validation CI.

.github/workflows/commit-validation.yml

@@ -7,35 +7,30 @@ permissions:
 jobs:
   check-commit-msg-length:
     runs-on: ubuntu-latest
+    id: check-commit-msg-length
     steps:
     - uses: actions/checkout@v3
     - name: Check commit message length
+      with:
+        result-encoding: json
+        script: |
+          var longlines = [];
+          const commits = ${{ toJSON(github.event.commits) }}
+          for (const commit of commits) {
+            if (/^.{79}/.test(commit.message)) {
+              longlines.push(commit.sha)
+            }
+          }
+          return longlines
+    - name: Get result
       run: |
-        # Get last commit messages
-        if [ "${{github.event_name}}" = "push" ]; then
-          if [ "${{github.event.before}}" = "0000000000000000000000000000000000000000" ]; then
-            # We are on a new branch
-            current="$(echo '${{github.ref}}' | sed 's!^refs/heads!origin!')"
-            readarray -t other < <(git show-ref | awk -F' ' '{ sub(/^refs\/remotes\//,"",$NF); }($NF != "'"$current"'"){print "^" $NF;}')
-            LOG_RANGE=( "$current" "${other[@]}" )
-            unset current other
-          else
-            # We are on existing branch
-            LOG_RANGE=( "${{github.event.before}}.." )
-          fi
-        elif [ "${{github.event_name}}" = "pull_request" ]; then
-          LOG_RANGE=( "origin/${{github.base_ref}}.." )
-        fi
-        if [[ -v LOG_RANGE ]]; then
-          if git log --no-merges --pretty=format:"%s" "${LOG_RANGE[@]}" -- | grep -qE "^[^#].{78}"; then
-            echo -e "Last commit log contains a line with more than 78 characters:\n"
-            git log --no-merges --pretty=format:"%h: %s" "${LOG_RANGE[@]}" -- | grep -E "^[^:]+: [^#].{78}"
-            echo
-            exit 1
-          else
-            echo "Commit log looks good."
-          fi
-          unset LOG_RANGE
+        result="${{steps.check-commit-msg-length.outputs.result}}"
+        if [[ $result = "" ]]; then
+          echo "Ok"
+          exit 0
         else
-          echo "Not checking commits on ${{github.event_name}}"
+          echo "Commit messages for these commits contain lines > 78 characters:"
+          echo $result
+          exit 1
         fi
+