more validations and tests

engine/ratingplan.go

@@ -160,6 +160,9 @@ func (rp *RatingPlan) areRatesSane() bool {
 				if math.Mod(nextRate.GroupIntervalStart.Seconds(), rate.RateIncrement.Seconds()) != 0 {
 					return false
 				}
+				if rate.RateUnit == 0 || rate.RateIncrement == 0 {
+					return false
+				}
 			}
 		}
 	}

engine/ratingplan_test.go

@@ -380,10 +380,12 @@ func TestRatingPlanSaneRatingsGoot(t *testing.T) {
 					&Rate{
 						GroupIntervalStart: 60 * time.Second,
 						RateIncrement:      30 * time.Second,
+						RateUnit:           1 * time.Second,
 					},
 					&Rate{
 						GroupIntervalStart: 0 * time.Second,
 						RateIncrement:      30 * time.Second,
+						RateUnit:           1 * time.Second,
 					},
 				},
 			},