Merge bitcoin/bitcoin#23438: refactor: Use spans of std::byte in serialize

fa5d2e678c809c26bd40d7e7c171529d3ffb5903 Remove unused char serialize (MarcoFalke)
fa24493d6394b3a477535f480664c9596f18e3c5 Use spans of std::byte in serialize (MarcoFalke)
fa65bbf217b725ada35107b4ad646d250228355c span: Add BytePtr helper (MarcoFalke)

Pull request description:

  This changes the serialize code (`.read()` and `.write()` functions) to take a `Span` instead of a pointer and size. This is a breaking change for the serialize interface, so at no additional cost we can also switch to `std::byte` (instead of using `char`).

  The benefits of using `Span`:
  * Less verbose and less fragile code when passing an already existing `Span`(-like) object to or from serialization

  The benefits of using `std::byte`:
  * `std::byte` can't accidentally be mistaken for an integer

  The goal here is to only change serialize to use spans of `std::byte`. If needed, `AsBytes`,  `MakeUCharSpan`, ... can be used (temporarily) to pass spans of the right type.

  Other changes that are included here:

  * [#22167](https://github.com/bitcoin/bitcoin/pull/22167) (refactor: Remove char serialize by MarcoFalke)
  * [#21906](https://github.com/bitcoin/bitcoin/pull/21906) (Preserve const in cast on CTransactionSignatureSerializer by promag)

ACKs for top commit:
  laanwj:
    Concept and code review ACK fa5d2e678c809c26bd40d7e7c171529d3ffb5903
  sipa:
    re-utACK fa5d2e678c809c26bd40d7e7c171529d3ffb5903

Tree-SHA512: 08ee9eced5fb777cedae593b11e33660bed9a3e1711a7451a87b835089a96c99ce0632918bb4666a4e859c4d020f88fb50f2dd734216b0c3d1a9a704967ece6f

9 files changed, 59 insertions, 60 deletions

diff --git a/src/test/bloom_tests.cpp b/src/test/bloom_tests.cpp
index bd579db205..35c4108caa 100644
--- a/src/test/bloom_tests.cpp
+++ b/src/test/bloom_tests.cpp
@@ -43,8 +43,9 @@ BOOST_AUTO_TEST_CASE(bloom_create_insert_serialize)
     stream << filter;
 
     std::vector<uint8_t> expected = ParseHex("03614e9b050000000000000001");
+    auto result{MakeUCharSpan(stream)};
 
-    BOOST_CHECK_EQUAL_COLLECTIONS(stream.begin(), stream.end(), expected.begin(), expected.end());
+    BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(), expected.begin(), expected.end());
 
     BOOST_CHECK_MESSAGE( filter.contains(ParseHex("99108ad8ed9bb6274d3980bab5a85c048f0950c8")), "Bloom filter doesn't contain just-inserted object!");
 }
@@ -69,8 +70,9 @@ BOOST_AUTO_TEST_CASE(bloom_create_insert_serialize_with_tweak)
     stream << filter;
 
     std::vector<uint8_t> expected = ParseHex("03ce4299050000000100008001");
+    auto result{MakeUCharSpan(stream)};
 
-    BOOST_CHECK_EQUAL_COLLECTIONS(stream.begin(), stream.end(), expected.begin(), expected.end());
+    BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(), expected.begin(), expected.end());
 }
 
 BOOST_AUTO_TEST_CASE(bloom_create_insert_key)
@@ -89,8 +91,9 @@ BOOST_AUTO_TEST_CASE(bloom_create_insert_key)
     stream << filter;
 
     std::vector<unsigned char> expected = ParseHex("038fc16b080000000000000001");
+    auto result{MakeUCharSpan(stream)};
 
-    BOOST_CHECK_EQUAL_COLLECTIONS(stream.begin(), stream.end(), expected.begin(), expected.end());
+    BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(), expected.begin(), expected.end());
 }
 
 BOOST_AUTO_TEST_CASE(bloom_match)
@@ -341,8 +344,9 @@ BOOST_AUTO_TEST_CASE(merkle_block_3_and_serialize)
     merkleStream << merkleBlock;
 
     std::vector<uint8_t> expected = ParseHex("0100000079cda856b143d9db2c1caff01d1aecc8630d30625d10e8b4b8b0000000000000b50cc069d6a3e33e3ff84a5c41d9d3febe7c770fdcc96b2c3ff60abe184f196367291b4d4c86041b8fa45d630100000001b50cc069d6a3e33e3ff84a5c41d9d3febe7c770fdcc96b2c3ff60abe184f19630101");
+    auto result{MakeUCharSpan(merkleStream)};
 
-    BOOST_CHECK_EQUAL_COLLECTIONS(expected.begin(), expected.end(), merkleStream.begin(), merkleStream.end());
+    BOOST_CHECK_EQUAL_COLLECTIONS(expected.begin(), expected.end(), result.begin(), result.end());
 }
 
 BOOST_AUTO_TEST_CASE(merkle_block_4)
diff --git a/src/test/fuzz/autofile.cpp b/src/test/fuzz/autofile.cpp
index 0cc2d12d29..3b410930ed 100644
--- a/src/test/fuzz/autofile.cpp
+++ b/src/test/fuzz/autofile.cpp
@@ -23,16 +23,16 @@ FUZZ_TARGET(autofile)
         CallOneOf(
             fuzzed_data_provider,
             [&] {
-                std::array<uint8_t, 4096> arr{};
+                std::array<std::byte, 4096> arr{};
                 try {
-                    auto_file.read((char*)arr.data(), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096));
+                    auto_file.read({arr.data(), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096)});
                 } catch (const std::ios_base::failure&) {
                 }
             },
             [&] {
-                const std::array<uint8_t, 4096> arr{};
+                const std::array<std::byte, 4096> arr{};
                 try {
-                    auto_file.write((const char*)arr.data(), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096));
+                    auto_file.write({arr.data(), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096)});
                 } catch (const std::ios_base::failure&) {
                 }
             },
diff --git a/src/test/fuzz/buffered_file.cpp b/src/test/fuzz/buffered_file.cpp
index c3c2e4050f..a8c3318629 100644
--- a/src/test/fuzz/buffered_file.cpp
+++ b/src/test/fuzz/buffered_file.cpp
@@ -33,9 +33,9 @@ FUZZ_TARGET(buffered_file)
             CallOneOf(
                 fuzzed_data_provider,
                 [&] {
-                    std::array<uint8_t, 4096> arr{};
+                    std::array<std::byte, 4096> arr{};
                     try {
-                        opt_buffered_file->read((char*)arr.data(), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096));
+                        opt_buffered_file->read({arr.data(), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 4096)});
                     } catch (const std::ios_base::failure&) {
                     }
                 },
@@ -53,7 +53,7 @@ FUZZ_TARGET(buffered_file)
                         return;
                     }
                     try {
-                        opt_buffered_file->FindByte(fuzzed_data_provider.ConsumeIntegral<char>());
+                        opt_buffered_file->FindByte(fuzzed_data_provider.ConsumeIntegral<uint8_t>());
                     } catch (const std::ios_base::failure&) {
                     }
                 },
diff --git a/src/test/fuzz/integer.cpp b/src/test/fuzz/integer.cpp
index 3087f11771..72574612a2 100644
--- a/src/test/fuzz/integer.cpp
+++ b/src/test/fuzz/integer.cpp
@@ -206,11 +206,6 @@ FUZZ_TARGET_INIT(integer, initialize_integer)
         stream >> deserialized_i8;
         assert(i8 == deserialized_i8 && stream.empty());
 
-        char deserialized_ch;
-        stream << ch;
-        stream >> deserialized_ch;
-        assert(ch == deserialized_ch && stream.empty());
-
         bool deserialized_b;
         stream << b;
         stream >> deserialized_b;
diff --git a/src/test/fuzz/rpc.cpp b/src/test/fuzz/rpc.cpp
index b6ecf1c492..73bfb7ff55 100644
--- a/src/test/fuzz/rpc.cpp
+++ b/src/test/fuzz/rpc.cpp
@@ -271,7 +271,7 @@ std::string ConsumeScalarRPCArgument(FuzzedDataProvider& fuzzed_data_provider)
             }
             CDataStream data_stream{SER_NETWORK, PROTOCOL_VERSION};
             data_stream << *opt_psbt;
-            r = EncodeBase64({data_stream.begin(), data_stream.end()});
+            r = EncodeBase64(data_stream);
         },
         [&] {
             // base58 encoded key
diff --git a/src/test/fuzz/util.h b/src/test/fuzz/util.h
index fd7f40c01d..3bc62878bd 100644
--- a/src/test/fuzz/util.h
+++ b/src/test/fuzz/util.h
@@ -328,7 +328,6 @@ void WriteToStream(FuzzedDataProvider& fuzzed_data_provider, Stream& stream) noe
             CallOneOf(
                 fuzzed_data_provider,
                 WRITE_TO_STREAM_CASE(bool, fuzzed_data_provider.ConsumeBool()),
-                WRITE_TO_STREAM_CASE(char, fuzzed_data_provider.ConsumeIntegral<char>()),
                 WRITE_TO_STREAM_CASE(int8_t, fuzzed_data_provider.ConsumeIntegral<int8_t>()),
                 WRITE_TO_STREAM_CASE(uint8_t, fuzzed_data_provider.ConsumeIntegral<uint8_t>()),
                 WRITE_TO_STREAM_CASE(int16_t, fuzzed_data_provider.ConsumeIntegral<int16_t>()),
@@ -338,7 +337,7 @@ void WriteToStream(FuzzedDataProvider& fuzzed_data_provider, Stream& stream) noe
                 WRITE_TO_STREAM_CASE(int64_t, fuzzed_data_provider.ConsumeIntegral<int64_t>()),
                 WRITE_TO_STREAM_CASE(uint64_t, fuzzed_data_provider.ConsumeIntegral<uint64_t>()),
                 WRITE_TO_STREAM_CASE(std::string, fuzzed_data_provider.ConsumeRandomLengthString(32)),
-                WRITE_TO_STREAM_CASE(std::vector<char>, ConsumeRandomLengthIntegralVector<char>(fuzzed_data_provider)));
+                WRITE_TO_STREAM_CASE(std::vector<uint8_t>, ConsumeRandomLengthIntegralVector<uint8_t>(fuzzed_data_provider)));
         } catch (const std::ios_base::failure&) {
             break;
         }
@@ -358,7 +357,6 @@ void ReadFromStream(FuzzedDataProvider& fuzzed_data_provider, Stream& stream) no
             CallOneOf(
                 fuzzed_data_provider,
                 READ_FROM_STREAM_CASE(bool),
-                READ_FROM_STREAM_CASE(char),
                 READ_FROM_STREAM_CASE(int8_t),
                 READ_FROM_STREAM_CASE(uint8_t),
                 READ_FROM_STREAM_CASE(int16_t),
@@ -368,7 +366,7 @@ void ReadFromStream(FuzzedDataProvider& fuzzed_data_provider, Stream& stream) no
                 READ_FROM_STREAM_CASE(int64_t),
                 READ_FROM_STREAM_CASE(uint64_t),
                 READ_FROM_STREAM_CASE(std::string),
-                READ_FROM_STREAM_CASE(std::vector<char>));
+                READ_FROM_STREAM_CASE(std::vector<uint8_t>));
         } catch (const std::ios_base::failure&) {
             break;
         }
diff --git a/src/test/script_tests.cpp b/src/test/script_tests.cpp
index 0da296495f..4906bd2386 100644
--- a/src/test/script_tests.cpp
+++ b/src/test/script_tests.cpp
@@ -155,10 +155,10 @@ void DoTest(const CScript& scriptPubKey, const CScript& scriptSig, const CScript
     if (libconsensus_flags == flags) {
         int expectedSuccessCode = expect ? 1 : 0;
         if (flags & bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS) {
-            BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script_with_amount(scriptPubKey.data(), scriptPubKey.size(), txCredit.vout[0].nValue, stream.data(), stream.size(), 0, libconsensus_flags, nullptr) == expectedSuccessCode, message);
+            BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script_with_amount(scriptPubKey.data(), scriptPubKey.size(), txCredit.vout[0].nValue, UCharCast(stream.data()), stream.size(), 0, libconsensus_flags, nullptr) == expectedSuccessCode, message);
         } else {
-            BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script_with_amount(scriptPubKey.data(), scriptPubKey.size(), 0, stream.data(), stream.size(), 0, libconsensus_flags, nullptr) == expectedSuccessCode, message);
-            BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), stream.data(), stream.size(), 0, libconsensus_flags, nullptr) == expectedSuccessCode, message);
+            BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script_with_amount(scriptPubKey.data(), scriptPubKey.size(), 0, UCharCast(stream.data()), stream.size(), 0, libconsensus_flags, nullptr) == expectedSuccessCode, message);
+            BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), UCharCast(stream.data()), stream.size(), 0, libconsensus_flags, nullptr) == expectedSuccessCode, message);
         }
     }
 #endif
@@ -1520,7 +1520,7 @@ BOOST_AUTO_TEST_CASE(bitcoinconsensus_verify_script_returns_true)
     stream << spendTx;
 
     bitcoinconsensus_error err;
-    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), stream.data(), stream.size(), nIn, libconsensus_flags, &err);
+    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), UCharCast(stream.data()), stream.size(), nIn, libconsensus_flags, &err);
     BOOST_CHECK_EQUAL(result, 1);
     BOOST_CHECK_EQUAL(err, bitcoinconsensus_ERR_OK);
 }
@@ -1543,7 +1543,7 @@ BOOST_AUTO_TEST_CASE(bitcoinconsensus_verify_script_tx_index_err)
     stream << spendTx;
 
     bitcoinconsensus_error err;
-    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), stream.data(), stream.size(), nIn, libconsensus_flags, &err);
+    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), UCharCast(stream.data()), stream.size(), nIn, libconsensus_flags, &err);
     BOOST_CHECK_EQUAL(result, 0);
     BOOST_CHECK_EQUAL(err, bitcoinconsensus_ERR_TX_INDEX);
 }
@@ -1566,7 +1566,7 @@ BOOST_AUTO_TEST_CASE(bitcoinconsensus_verify_script_tx_size)
     stream << spendTx;
 
     bitcoinconsensus_error err;
-    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), stream.data(), stream.size() * 2, nIn, libconsensus_flags, &err);
+    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), UCharCast(stream.data()), stream.size() * 2, nIn, libconsensus_flags, &err);
     BOOST_CHECK_EQUAL(result, 0);
     BOOST_CHECK_EQUAL(err, bitcoinconsensus_ERR_TX_SIZE_MISMATCH);
 }
@@ -1589,7 +1589,7 @@ BOOST_AUTO_TEST_CASE(bitcoinconsensus_verify_script_tx_serialization)
     stream << 0xffffffff;
 
     bitcoinconsensus_error err;
-    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), stream.data(), stream.size(), nIn, libconsensus_flags, &err);
+    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), UCharCast(stream.data()), stream.size(), nIn, libconsensus_flags, &err);
     BOOST_CHECK_EQUAL(result, 0);
     BOOST_CHECK_EQUAL(err, bitcoinconsensus_ERR_TX_DESERIALIZE);
 }
@@ -1612,7 +1612,7 @@ BOOST_AUTO_TEST_CASE(bitcoinconsensus_verify_script_amount_required_err)
     stream << spendTx;
 
     bitcoinconsensus_error err;
-    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), stream.data(), stream.size(), nIn, libconsensus_flags, &err);
+    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), UCharCast(stream.data()), stream.size(), nIn, libconsensus_flags, &err);
     BOOST_CHECK_EQUAL(result, 0);
     BOOST_CHECK_EQUAL(err, bitcoinconsensus_ERR_AMOUNT_REQUIRED);
 }
@@ -1635,7 +1635,7 @@ BOOST_AUTO_TEST_CASE(bitcoinconsensus_verify_script_invalid_flags)
     stream << spendTx;
 
     bitcoinconsensus_error err;
-    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), stream.data(), stream.size(), nIn, libconsensus_flags, &err);
+    int result = bitcoinconsensus_verify_script(scriptPubKey.data(), scriptPubKey.size(), UCharCast(stream.data()), stream.size(), nIn, libconsensus_flags, &err);
     BOOST_CHECK_EQUAL(result, 0);
     BOOST_CHECK_EQUAL(err, bitcoinconsensus_ERR_INVALID_FLAGS);
 }
diff --git a/src/test/serialize_tests.cpp b/src/test/serialize_tests.cpp
index e91c203c26..8b8133b689 100644
--- a/src/test/serialize_tests.cpp
+++ b/src/test/serialize_tests.cpp
@@ -61,7 +61,7 @@ public:
 
 BOOST_AUTO_TEST_CASE(sizes)
 {
-    BOOST_CHECK_EQUAL(sizeof(char), GetSerializeSize(char(0), 0));
+    BOOST_CHECK_EQUAL(sizeof(unsigned char), GetSerializeSize((unsigned char)0, 0));
     BOOST_CHECK_EQUAL(sizeof(int8_t), GetSerializeSize(int8_t(0), 0));
     BOOST_CHECK_EQUAL(sizeof(uint8_t), GetSerializeSize(uint8_t(0), 0));
     BOOST_CHECK_EQUAL(sizeof(int16_t), GetSerializeSize(int16_t(0), 0));
@@ -74,7 +74,7 @@ BOOST_AUTO_TEST_CASE(sizes)
     BOOST_CHECK_EQUAL(sizeof(uint8_t), GetSerializeSize(bool(0), 0));
 
     // Sanity-check GetSerializeSize and c++ type matching
-    BOOST_CHECK_EQUAL(GetSerializeSize(char(0), 0), 1U);
+    BOOST_CHECK_EQUAL(GetSerializeSize((unsigned char)0, 0), 1U);
     BOOST_CHECK_EQUAL(GetSerializeSize(int8_t(0), 0), 1U);
     BOOST_CHECK_EQUAL(GetSerializeSize(uint8_t(0), 0), 1U);
     BOOST_CHECK_EQUAL(GetSerializeSize(int16_t(0), 0), 2U);
@@ -186,76 +186,78 @@ BOOST_AUTO_TEST_CASE(noncanonical)
     std::vector<char>::size_type n;
 
     // zero encoded with three bytes:
-    ss.write("\xfd\x00\x00", 3);
+    ss.write(MakeByteSpan("\xfd\x00\x00").first(3));
     BOOST_CHECK_EXCEPTION(ReadCompactSize(ss), std::ios_base::failure, isCanonicalException);
 
     // 0xfc encoded with three bytes:
-    ss.write("\xfd\xfc\x00", 3);
+    ss.write(MakeByteSpan("\xfd\xfc\x00").first(3));
     BOOST_CHECK_EXCEPTION(ReadCompactSize(ss), std::ios_base::failure, isCanonicalException);
 
     // 0xfd encoded with three bytes is OK:
-    ss.write("\xfd\xfd\x00", 3);
+    ss.write(MakeByteSpan("\xfd\xfd\x00").first(3));
     n = ReadCompactSize(ss);
     BOOST_CHECK(n == 0xfd);
 
     // zero encoded with five bytes:
-    ss.write("\xfe\x00\x00\x00\x00", 5);
+    ss.write(MakeByteSpan("\xfe\x00\x00\x00\x00").first(5));
     BOOST_CHECK_EXCEPTION(ReadCompactSize(ss), std::ios_base::failure, isCanonicalException);
 
     // 0xffff encoded with five bytes:
-    ss.write("\xfe\xff\xff\x00\x00", 5);
+    ss.write(MakeByteSpan("\xfe\xff\xff\x00\x00").first(5));
     BOOST_CHECK_EXCEPTION(ReadCompactSize(ss), std::ios_base::failure, isCanonicalException);
 
     // zero encoded with nine bytes:
-    ss.write("\xff\x00\x00\x00\x00\x00\x00\x00\x00", 9);
+    ss.write(MakeByteSpan("\xff\x00\x00\x00\x00\x00\x00\x00\x00").first(9));
     BOOST_CHECK_EXCEPTION(ReadCompactSize(ss), std::ios_base::failure, isCanonicalException);
 
     // 0x01ffffff encoded with nine bytes:
-    ss.write("\xff\xff\xff\xff\x01\x00\x00\x00\x00", 9);
+    ss.write(MakeByteSpan("\xff\xff\xff\xff\x01\x00\x00\x00\x00").first(9));
     BOOST_CHECK_EXCEPTION(ReadCompactSize(ss), std::ios_base::failure, isCanonicalException);
 }
 
 BOOST_AUTO_TEST_CASE(insert_delete)
 {
+    constexpr auto B2I{[](std::byte b) { return std::to_integer<uint8_t>(b); }};
+
     // Test inserting/deleting bytes.
     CDataStream ss(SER_DISK, 0);
     BOOST_CHECK_EQUAL(ss.size(), 0U);
 
-    ss.write("\x00\x01\x02\xff", 4);
+    ss.write(MakeByteSpan("\x00\x01\x02\xff").first(4));
     BOOST_CHECK_EQUAL(ss.size(), 4U);
 
-    char c = (char)11;
+    uint8_t c{11};
 
     // Inserting at beginning/end/middle:
-    ss.insert(ss.begin(), c);
+    ss.insert(ss.begin(), std::byte{c});
     BOOST_CHECK_EQUAL(ss.size(), 5U);
-    BOOST_CHECK_EQUAL(ss[0], c);
-    BOOST_CHECK_EQUAL(ss[1], 0);
+    BOOST_CHECK_EQUAL(B2I(ss[0]), c);
+    BOOST_CHECK_EQUAL(B2I(ss[1]), 0);
 
-    ss.insert(ss.end(), c);
+    ss.insert(ss.end(), std::byte{c});
     BOOST_CHECK_EQUAL(ss.size(), 6U);
-    BOOST_CHECK_EQUAL(ss[4], 0xff);
-    BOOST_CHECK_EQUAL(ss[5], c);
+    BOOST_CHECK_EQUAL(B2I(ss[4]), 0xff);
+    BOOST_CHECK_EQUAL(B2I(ss[5]), c);
 
-    ss.insert(ss.begin()+2, c);
+    ss.insert(ss.begin() + 2, std::byte{c});
     BOOST_CHECK_EQUAL(ss.size(), 7U);
-    BOOST_CHECK_EQUAL(ss[2], c);
+    BOOST_CHECK_EQUAL(B2I(ss[2]), c);
 
     // Delete at beginning/end/middle
     ss.erase(ss.begin());
     BOOST_CHECK_EQUAL(ss.size(), 6U);
-    BOOST_CHECK_EQUAL(ss[0], 0);
+    BOOST_CHECK_EQUAL(B2I(ss[0]), 0);
 
     ss.erase(ss.begin()+ss.size()-1);
     BOOST_CHECK_EQUAL(ss.size(), 5U);
-    BOOST_CHECK_EQUAL(ss[4], 0xff);
+    BOOST_CHECK_EQUAL(B2I(ss[4]), 0xff);
 
     ss.erase(ss.begin()+1);
     BOOST_CHECK_EQUAL(ss.size(), 4U);
-    BOOST_CHECK_EQUAL(ss[0], 0);
-    BOOST_CHECK_EQUAL(ss[1], 1);
-    BOOST_CHECK_EQUAL(ss[2], 2);
-    BOOST_CHECK_EQUAL(ss[3], 0xff);
+    BOOST_CHECK_EQUAL(B2I(ss[0]), 0);
+    BOOST_CHECK_EQUAL(B2I(ss[1]), 1);
+    BOOST_CHECK_EQUAL(B2I(ss[2]), 2);
+    BOOST_CHECK_EQUAL(B2I(ss[3]), 0xff);
 }
 
 BOOST_AUTO_TEST_CASE(class_methods)
diff --git a/src/test/streams_tests.cpp b/src/test/streams_tests.cpp
index 3571927397..a8f6cdd4a0 100644
--- a/src/test/streams_tests.cpp
+++ b/src/test/streams_tests.cpp
@@ -160,7 +160,7 @@ BOOST_AUTO_TEST_CASE(bitstream_reader_writer)
 
 BOOST_AUTO_TEST_CASE(streams_serializedata_xor)
 {
-    std::vector<uint8_t> in;
+    std::vector<std::byte> in;
     std::vector<char> expected_xor;
     std::vector<unsigned char> key;
     CDataStream ds(in, 0, 0);
@@ -174,8 +174,8 @@ BOOST_AUTO_TEST_CASE(streams_serializedata_xor)
             std::string(expected_xor.begin(), expected_xor.end()),
             ds.str());
 
-    in.push_back('\x0f');
-    in.push_back('\xf0');
+    in.push_back(std::byte{0x0f});
+    in.push_back(std::byte{0xf0});
     expected_xor.push_back('\xf0');
     expected_xor.push_back('\x0f');
 
@@ -195,8 +195,8 @@ BOOST_AUTO_TEST_CASE(streams_serializedata_xor)
 
     in.clear();
     expected_xor.clear();
-    in.push_back('\xf0');
-    in.push_back('\x0f');
+    in.push_back(std::byte{0xf0});
+    in.push_back(std::byte{0x0f});
     expected_xor.push_back('\x0f');
     expected_xor.push_back('\x00');