Fix nil pointer panic in comment updater when backend API returns nil

cli/pkg/digger/digger.go

@@ -148,10 +148,15 @@ func RunJobs(jobs []orchestrator.Job, prService ci.PullRequestService, orgServic
 			return false, false, fmt.Errorf("error while running command: %v", err)
 		}
 
-		err = commentUpdater.UpdateComment(batchResult.Jobs, prNumber, prService, prCommentId)
-		if err != nil {
-			slog.Error("error Updating status comment", "error", err)
-			return false, false, err
+		// Check if batchResult is nil (can happen with mock backend or when backend is not configured)
+		if batchResult == nil {
+			slog.Warn("batchResult is nil, skipping comment update", "jobId", jobId, "prNumber", prNumber)
+		} else {
+			err = commentUpdater.UpdateComment(batchResult.Jobs, prNumber, prService, prCommentId)
+			if err != nil {
+				slog.Error("error Updating status comment", "error", err, "prNumber", prNumber, "jobId", jobId)
+				return false, false, err
+			}
 		}
 
 	}

cli/pkg/spec/spec.go

@@ -163,7 +163,12 @@ func RunSpec(
 			message := fmt.Sprintf("Failed run commands. %v", err)
 			reportError(spec, backendApi, message, err)
 		}
-		commentUpdater.UpdateComment(serializedBatch.Jobs, serializedBatch.PrNumber, prService, commentId)
+		// Check if serializedBatch is nil (can happen with mock backend or when backend is not configured)
+		if serializedBatch == nil {
+			slog.Warn("serializedBatch is nil, skipping comment update", "jobId", spec.JobId)
+		} else {
+			commentUpdater.UpdateComment(serializedBatch.Jobs, serializedBatch.PrNumber, prService, commentId)
+		}
 		reportError(spec, backendApi, fmt.Sprintf("failed to run commands %v", err), err)
 	}
 	usage.ReportErrorAndExit(spec.VCS.RepoOwner, "Digger finished successfully", 0)

libs/comment_utils/summary/updater.go

@@ -24,6 +24,11 @@ func (b BasicCommentUpdater) UpdateComment(jobs []scheduler.SerializedJob, prNum
 		return err
 	}
 
+	if len(jobSpecs) == 0 {
+		slog.Warn("no job specs found, cannot update comment", "jobCount", len(jobs))
+		return nil
+	}
+
 	firstJobSpec := jobSpecs[0]
 	jobType := firstJobSpec.JobType
 	jobTypeTitle := cases.Title(language.AmericanEnglish).String(string(jobType))