Merge bitcoin/bitcoin#25296: Add DataStream without ser-type and ser-version and use it where possible

fa035fe2d61d0c98d1bfd0153a0c3b5eb9d40de4 Remove unused CDataStream::SetType (MarcoFalke)
fa29e73cdab82f98682821322cda89b1084ba887 Use DataStream where possible (MarcoFalke)
fa9becfe1cea5040e7cea36324d1b0789cbbd25d streams: Add DataStream without ser-type and ser-version (MarcoFalke)

Pull request description:

  This was done in the context of https://github.com/bitcoin/bitcoin/pull/25284 , but I think it also makes sense standalone.

  The basic idea is that serialization type should not be initialized when it is not needed. Same for the serialization version.

  So do this here for `DataStream`. `CDataStream` remains in places where it is not yet possible.

ACKs for top commit:
  stickies-v:
    re-ACK [fa035fe](https://github.com/bitcoin/bitcoin/commit/fa035fe2d61d0c98d1bfd0153a0c3b5eb9d40de4)
  aureleoules:
    diff re-ACK fa035fe2d61d0c98d1bfd0153a0c3b5eb9d40de4 https://github.com/bitcoin/bitcoin/compare/fa0e6640bac8c6426af7c5744125c85c0f74b9e5..fa035fe2d61d0c98d1bfd0153a0c3b5eb9d40de4

Tree-SHA512: cb5e53d0df7c94319ffadc6ea1d887fc38516decaf43f0673396d79cc62d450a1a61173654a91b8c2b52d2cecea53fe4a500b8f6466596f35731471163fb051c

7 files changed, 11 insertions, 17 deletions

diff --git a/src/test/fuzz/integer.cpp b/src/test/fuzz/integer.cpp
index 7965f90dc7..c0aefe6067 100644
--- a/src/test/fuzz/integer.cpp
+++ b/src/test/fuzz/integer.cpp
@@ -152,7 +152,7 @@ FUZZ_TARGET_INIT(integer, initialize_integer)
     const CScriptID script_id{u160};
 
     {
-        CDataStream stream(SER_NETWORK, INIT_PROTO_VERSION);
+        DataStream stream{};
 
         uint256 deserialized_u256;
         stream << u256;
@@ -217,7 +217,7 @@ FUZZ_TARGET_INIT(integer, initialize_integer)
     }
 
     {
-        CDataStream stream(SER_NETWORK, INIT_PROTO_VERSION);
+        DataStream stream{};
 
         ser_writedata64(stream, u64);
         const uint64_t deserialized_u64 = ser_readdata64(stream);
@@ -245,7 +245,7 @@ FUZZ_TARGET_INIT(integer, initialize_integer)
     }
 
     {
-        CDataStream stream(SER_NETWORK, INIT_PROTO_VERSION);
+        DataStream stream{};
 
         WriteCompactSize(stream, u64);
         try {
diff --git a/src/test/fuzz/key.cpp b/src/test/fuzz/key.cpp
index e83606f032..ea6883c08d 100644
--- a/src/test/fuzz/key.cpp
+++ b/src/test/fuzz/key.cpp
@@ -111,7 +111,7 @@ FUZZ_TARGET_INIT(key, initialize_key)
     }
 
     {
-        CDataStream data_stream{SER_NETWORK, INIT_PROTO_VERSION};
+        DataStream data_stream{};
         pubkey.Serialize(data_stream);
 
         CPubKey pubkey_deserialized;
diff --git a/src/test/fuzz/prevector.cpp b/src/test/fuzz/prevector.cpp
index c8fd9aca30..9cea32e304 100644
--- a/src/test/fuzz/prevector.cpp
+++ b/src/test/fuzz/prevector.cpp
@@ -59,8 +59,8 @@ public:
             --pos;
             assert(v == real_vector[pos]);
         }
-        CDataStream ss1(SER_DISK, 0);
-        CDataStream ss2(SER_DISK, 0);
+        DataStream ss1{};
+        DataStream ss2{};
         ss1 << real_vector;
         ss2 << pre_vector;
         assert(ss1.size() == ss2.size());
diff --git a/src/test/fuzz/rpc.cpp b/src/test/fuzz/rpc.cpp
index 361cfa6cb6..2578137471 100644
--- a/src/test/fuzz/rpc.cpp
+++ b/src/test/fuzz/rpc.cpp
@@ -253,7 +253,7 @@ std::string ConsumeScalarRPCArgument(FuzzedDataProvider& fuzzed_data_provider)
             if (!opt_block_header) {
                 return;
             }
-            CDataStream data_stream{SER_NETWORK, PROTOCOL_VERSION};
+            DataStream data_stream{};
             data_stream << *opt_block_header;
             r = HexStr(data_stream);
         },
diff --git a/src/test/fuzz/string.cpp b/src/test/fuzz/string.cpp
index 3c427b9bef..9890e4c0e5 100644
--- a/src/test/fuzz/string.cpp
+++ b/src/test/fuzz/string.cpp
@@ -196,7 +196,7 @@ FUZZ_TARGET(string)
     }
 
     {
-        CDataStream data_stream{SER_NETWORK, INIT_PROTO_VERSION};
+        DataStream data_stream{};
         std::string s;
         auto limited_string = LIMITED_STRING(s, 10);
         data_stream << random_string_1;
@@ -212,7 +212,7 @@ FUZZ_TARGET(string)
         }
     }
     {
-        CDataStream data_stream{SER_NETWORK, INIT_PROTO_VERSION};
+        DataStream data_stream{};
         const auto limited_string = LIMITED_STRING(random_string_1, 10);
         data_stream << limited_string;
         std::string deserialized_string;
diff --git a/src/test/fuzz/tx_in.cpp b/src/test/fuzz/tx_in.cpp
index f8247c1fa4..fc16f80cde 100644
--- a/src/test/fuzz/tx_in.cpp
+++ b/src/test/fuzz/tx_in.cpp
@@ -14,12 +14,9 @@
 
 FUZZ_TARGET(tx_in)
 {
-    CDataStream ds(buffer, SER_NETWORK, INIT_PROTO_VERSION);
+    DataStream ds{buffer};
     CTxIn tx_in;
     try {
-        int version;
-        ds >> version;
-        ds.SetVersion(version);
         ds >> tx_in;
     } catch (const std::ios_base::failure&) {
         return;
diff --git a/src/test/fuzz/tx_out.cpp b/src/test/fuzz/tx_out.cpp
index 337b8e2771..806216fbf5 100644
--- a/src/test/fuzz/tx_out.cpp
+++ b/src/test/fuzz/tx_out.cpp
@@ -13,12 +13,9 @@
 
 FUZZ_TARGET(tx_out)
 {
-    CDataStream ds(buffer, SER_NETWORK, INIT_PROTO_VERSION);
+    DataStream ds{buffer};
     CTxOut tx_out;
     try {
-        int version;
-        ds >> version;
-        ds.SetVersion(version);
         ds >> tx_out;
     } catch (const std::ios_base::failure&) {
         return;