t.Error("got versions", e.Versions, "want", w.objs)
			}
			if e.ObjSizes != w.oSizes {
				t.Error("got histogram", e.ObjSizes, "want", w.oSizes)
			}
		})
	}
}

func TestDataUsageUpdatePrefix(t *testing.T) {
	base := t.TempDir()
	scannerSleeper.Update(0, 0)
	files := []usageTestFile{
		{name: "bucket/rootfile", size: 10000},
		{name: "bucket/rootfile2", size: 10000},