Fix PipelineRunStatus Reconciler Updates and Tests for EmbeddedStatus…

… Switch

This commit fixes the updates for reconciling PipelineRunStatus when switching
the DefaultEmbeddedStatus from `Full` to `Minimal`. The prior runs or taskruns
status would not have been reset before this change. The related emtpy runs and
taskruns are removed because these fields will be `nil`. It also applies for the
switch from `Minimal` to `Full`.

pkg/reconciler/pipelinerun/pipelinerun.go

@@ -1331,15 +1331,20 @@ func (c *Reconciler) updatePipelineRunStatusFromInformer(ctx context.Context, pr
 
 func updatePipelineRunStatusFromChildObjects(ctx context.Context, logger *zap.SugaredLogger, pr *v1beta1.PipelineRun, taskRuns []*v1beta1.TaskRun, runObjects []v1beta1.RunObject) error {
 	cfg := config.FromContextOrDefaults(ctx)
-	fullEmbedded := cfg.FeatureFlags.EmbeddedStatus == config.FullEmbeddedStatus || cfg.FeatureFlags.EmbeddedStatus == config.BothEmbeddedStatus
-	minimalEmbedded := cfg.FeatureFlags.EmbeddedStatus == config.MinimalEmbeddedStatus || cfg.FeatureFlags.EmbeddedStatus == config.BothEmbeddedStatus
 
-	if minimalEmbedded {
-		updatePipelineRunStatusFromChildRefs(logger, pr, taskRuns, runObjects)
-	}
-	if fullEmbedded {
+	switch cfg.FeatureFlags.EmbeddedStatus {
+	case config.FullEmbeddedStatus:
+		pr.Status.ChildReferences = nil
+		updatePipelineRunStatusFromTaskRuns(logger, pr, taskRuns)
+		updatePipelineRunStatusFromCustomRunsOrRuns(logger, pr, runObjects)
+	case config.BothEmbeddedStatus:
 		updatePipelineRunStatusFromTaskRuns(logger, pr, taskRuns)
 		updatePipelineRunStatusFromCustomRunsOrRuns(logger, pr, runObjects)
+		updatePipelineRunStatusFromChildRefs(logger, pr, taskRuns, runObjects)
+	default:
+		pr.Status.Runs = nil
+		pr.Status.TaskRuns = nil
+		updatePipelineRunStatusFromChildRefs(logger, pr, taskRuns, runObjects)
 	}
 
 	return validateChildObjectsInPipelineRunStatus(ctx, pr.Status)
@@ -1350,6 +1355,8 @@ func validateChildObjectsInPipelineRunStatus(ctx context.Context, prs v1beta1.Pi
 
 	var err error
 
+	// TODO: Integration test to be introduced for switching in embeddedStatus
+	// https://github.com/tektoncd/pipeline/issues/5999
 	// Verify that we don't populate child references for "full"
 	if cfg.FeatureFlags.EmbeddedStatus == config.FullEmbeddedStatus && len(prs.ChildReferences) > 0 {
 		return fmt.Errorf("expected no ChildReferences with embedded-status=full, but found %d", len(prs.ChildReferences))