Do not scale gantry collector returns from Lengths and Positions (#…

…4362)

components/gantry/collectors.go

@@ -46,7 +46,7 @@ func newPositionCollector(resource interface{}, params data.CollectorParams) (da
 			return nil, data.FailedToReadErr(params.ComponentName, position.String(), err)
 		}
 		return pb.GetPositionResponse{
-			PositionsMm: scaleMetersToMm(v),
+			PositionsMm: v,
 		}, nil
 	})
 	return data.NewCollector(cFunc, params)
@@ -71,20 +71,12 @@ func newLengthsCollector(resource interface{}, params data.CollectorParams) (dat
 			return nil, data.FailedToReadErr(params.ComponentName, lengths.String(), err)
 		}
 		return pb.GetLengthsResponse{
-			LengthsMm: scaleMetersToMm(v),
+			LengthsMm: v,
 		}, nil
 	})
 	return data.NewCollector(cFunc, params)
 }
 
-func scaleMetersToMm(meters []float64) []float64 {
-	ret := make([]float64, len(meters))
-	for i := range ret {
-		ret[i] = meters[i] * 1000
-	}
-	return ret
-}
-
 func assertGantry(resource interface{}) (Gantry, error) {
 	gantry, ok := resource.(Gantry)
 	if !ok {

components/gantry/collectors_test.go

@@ -22,7 +22,8 @@ const (
 	numRetries      = 5
 )
 
-var floatList = []float64{1.0, 2.0, 3.0}
+// floatList is a lit of floats in units of millimeters.
+var floatList = []float64{1000, 2000, 3000}
 
 func TestGantryCollectors(t *testing.T) {
 	tests := []struct {
@@ -34,14 +35,14 @@ func TestGantryCollectors(t *testing.T) {
 			name:      "Length collector should write a lengths response",
 			collector: gantry.NewLengthsCollector,
 			expected: tu.ToProtoMapIgnoreOmitEmpty(pb.GetLengthsResponse{
-				LengthsMm: scaleMetersToMm(floatList),
+				LengthsMm: floatList,
 			}),
 		},
 		{
 			name:      "Position collector should write a list of positions",
 			collector: gantry.NewPositionCollector,
 			expected: tu.ToProtoMapIgnoreOmitEmpty(pb.GetPositionResponse{
-				PositionsMm: scaleMetersToMm(floatList),
+				PositionsMm: floatList,
 			}),
 		},
 	}
@@ -85,11 +86,3 @@ func newGantry() gantry.Gantry {
 	}
 	return g
 }
-
-func scaleMetersToMm(meters []float64) []float64 {
-	ret := make([]float64, len(meters))
-	for i := range ret {
-		ret[i] = meters[i] * 1000
-	}
-	return ret
-}