diff --git a/space_test.go b/space_test.go
index d0ec7c4..7c668e8 100644
--- a/space_test.go
+++ b/space_test.go
@@ -27,7 +27,18 @@ func TestSpace_ShapeQuery(t *testing.T) {
 func TestSpace_ReindexShape(t *testing.T) {
 	space := NewSpace()
 	circle := space.AddShape(NewCircle(space.StaticBody, 1, Vector{}))
+	bb1 := circle.bb
 	space.ReindexShape(circle)
+	bb2 := circle.bb
+	// check unchanged
+	if got, want := bb1.String(), bb2.String(); got != want {
+		t.Errorf("got [%[1]v:%[1]T] want [%[2]v:%[2]T]", got, want)
+	}
 	circle.body.SetPosition(Vector{X: 12.0, Y: 34.0})
 	space.ReindexShape(circle)
+	bb3 := circle.bb
+	// check changed
+	if got, want := bb2.String(), bb3.String(); got == want {
+		t.Errorf("got [%[1]v:%[1]T] want [%[2]v:%[2]T]", got, want)
+	}
 }