// Test success cases.
	successCases := []struct {
		rangeString string
		offsetBegin int64
		offsetEnd   int64
	}{
		{"bytes=2-5", 2, 5},
		{"bytes=2-9", 2, 9},
		{"bytes=2-2", 2, 2},
		{"bytes=0000-0006", 0, 6},
	}
	objectSize := int64(10)

	for _, successCase := range successCases {
		rs, err := parseCopyPartRangeSpec(successCase.rangeString)
		if err != nil {
			t.Fatalf("expected: <nil>, got: %s", err)
		}