Cover the loss window, rate window, error taxonomy and formatters with tests

probe_test.go

@@ -0,0 +1,25 @@
+package main
+
+import "testing"
+
+func stamped(min, floor int64) view {
+	return view{cable: cableView{min: min, floor: floor, ok: true}}
+}
+
+// Averaged across directions, since one direction alone carries a phy asymmetry
+// that swamps the cable.
+func TestCableMetresAveragesDirections(t *testing.T) {
+	m, ok := cableMetres([]view{stamped(1000, 900), stamped(1100, 900)}, 5)
+	if !ok || m != 30 {
+		t.Errorf("cableMetres = %v, %v; want 30, true", m, ok)
+	}
+}
+
+func TestCableMetresNeedsEveryDirection(t *testing.T) {
+	if _, ok := cableMetres(nil, 5); ok {
+		t.Error("no views should not yield a length")
+	}
+	if _, ok := cableMetres([]view{stamped(1000, 900), {}}, 5); ok {
+		t.Error("a direction with no stamp yet should not yield a length")
+	}
+}