cover planner node deletion latency tracking with test

Author: ttetyanka

cluster-autoscaler/core/scaledown/latencytracker/node_latency_tracker.go

@@ -74,3 +74,12 @@ func (t *NodeLatencyTracker) ObserveDeletion(nodeName string, timestamp time.Tim
 		delete(t.nodes, nodeName)
 	}
 }
+
+// GetTrackedNodes returns the names of all nodes currently tracked as unneeded.
+func (t *NodeLatencyTracker) GetTrackedNodes() []string {
+	names := make([]string, 0, len(t.nodes))
+	for name := range t.nodes {
+		names = append(names, name)
+	}
+	return names
+}

cluster-autoscaler/core/scaledown/planner/planner_test.go

@@ -519,6 +519,13 @@ func TestUpdateClusterState(t *testing.T) {
 				assert.Equal(t, wantUnneeded[n.Name], p.unneededNodes.Contains(n.Name), []string{n.Name, "unneeded"})
 				assert.Equal(t, wantUnremovable[n.Name], p.unremovableNodes.Contains(n.Name), []string{n.Name, "unremovable"})
 			}
+			tracked := p.nodeLatencyTracker.GetTrackedNodes()
+			for _, name := range tc.wantUnneeded {
+				assert.Contains(t, tracked, name, "expected node in latency tracker")
+			}
+			for _, name := range tc.wantUnremovable {
+				assert.NotContains(t, tracked, name, "expected node not in latency tracker")
+			}
 		})
 	}
 }