a[i] = (byte) i;
        }
        return a;
    }

    @ParameterizedTest
    @MethodSource("byteEncodableArgs")
    @DisplayName("encode() copies bytes correctly and returns size")
    void encodeCopiesAndReportsSize(byte[] src, int off, int len, int dstIndex) {
        Encodable enc = new ByteEncodable(src, off, len);

        // Destination has guard space to verify non-overwritten regions.