Merge branch 'develop' into ximinez/parse-guard

- Rename oldExpected to oldExpected_.
- Prevent copying, and moving.
- Make getParseFailureGuard [[nodiscard]].

.clang-tidy

@@ -50,13 +50,7 @@ Checks: "-*,
   performance-*,
   -performance-avoid-endl,
   -performance-enum-size,
-  -performance-inefficient-algorithm,
-  -performance-inefficient-string-concatenation,
-  -performance-no-int-to-ptr,
-  -performance-noexcept-destructor,
   -performance-noexcept-move-constructor,
-  -performance-noexcept-swap,
-  -performance-type-promotion-in-math-fn,
   -performance-unnecessary-copy-initialization,
   -performance-unnecessary-value-param,
 

.envrc

@@ -0,0 +1 @@
+use flake

docs/build/environment.md

@@ -33,9 +33,10 @@ with a single command and without installing anything system-wide:
 nix --experimental-features 'nix-command flakes' develop
 ```
 
-On **Linux**, Nix also provides the compiler (GCC). On **macOS**, the shell uses
-your **system-wide Apple Clang** as the compiler, so you still need to manage
-its version (see below).
+On **Linux**, Nix also provides the compiler (GCC); on **macOS**, it provides
+Clang. If you instead opt to use your system-wide Apple Clang (via
+`nix develop .#apple-clang`), you need to manage its version yourself (see
+below).
 
 See [Using the Nix development shell](./nix.md) for installation and usage
 details, including how to select a different compiler.
@@ -48,10 +49,10 @@ details, including how to select a different compiler.
 
 ### macOS: managing the Apple Clang version
 
-Because the Nix shell uses the system-wide Apple Clang on macOS, the compiler
-version is whatever your installed Xcode (or Command Line Tools) provides. The
-following command should return a version greater than or equal to the
-[minimum required](#tested-compiler-versions):
+If you use your system-wide Apple Clang on macOS (via `nix develop .#apple-clang`),
+the compiler version is whatever your installed Xcode (or Command Line Tools)
+provides. The following command should return a version greater than or equal to
+the [minimum required](#tested-compiler-versions):
 
 ```bash
 clang --version

docs/build/nix.md

@@ -9,7 +9,7 @@ This guide explains how to use Nix to set up a reproducible development environm
 - **Reproducible environment**: Everyone gets the same versions of tools and compilers
 - **Matches CI**: The Linux CI runs in Docker images built from this exact Nix environment
 - **No system pollution**: Dependencies are isolated and don't affect your system packages
-- **Multiple compiler versions**: Easily switch between different GCC and Clang versions
+- **Consistent compilers**: The GCC and Clang shells use the same versions as CI
 - **Quick setup**: Get started with a single command
 - **Works on Linux and macOS**: Consistent experience across platforms
 
@@ -31,8 +31,8 @@ This will:
 
 - Download and set up all required development tools (CMake, Ninja, Conan, etc.)
 - Configure the appropriate compiler for your platform:
-  - **Linux**: GCC 15.2 (provided by Nix)
-  - **macOS**: Apple Clang (your system compiler)
+  - **Linux**: GCC (provided by Nix)
+  - **macOS**: Clang (provided by Nix)
 
 The first time you run this command, it will take a few minutes to download and build the environment. Subsequent runs will be much faster.
 
@@ -40,12 +40,12 @@ The first time you run this command, it will take a few minutes to download and
 
 - **Linux**: `nix develop` gives you a shell with all the tooling necessary to
   develop xrpld and with GCC 15.2 (also provided by Nix). There are no caveats.
-- **macOS**: `nix develop` gives you a full environment too. The compiler is
-  your system-wide Apple Clang, while every other tool — including Conan — is
-  provided by Nix. Conan has no binary in the Nix cache for macOS, so it is
-  built from source the first time you enter the shell, which makes the initial
-  setup slower (this is handled automatically; see
-  [`nix/devshell.nix`](../../nix/devshell.nix)).
+- **macOS**: `nix develop` gives you a full environment too, with Clang (and
+  every other tool, including Conan) provided by Nix. To use your system-wide
+  Apple Clang instead, enter `nix develop .#apple-clang`. Conan has no binary in
+  the Nix cache for macOS, so it is built from source the first time you enter
+  the shell, which makes the initial setup slower (this is handled
+  automatically; see [`nix/devshell.nix`](../../nix/devshell.nix)).
 
 > [!TIP]
 > To avoid typing `--experimental-features 'nix-command flakes'` every time, you can permanently enable flakes by creating `~/.config/nix/nix.conf`:
@@ -62,7 +62,9 @@ The first time you run this command, it will take a few minutes to download and
 
 ### Choosing a different compiler
 
-A compiler can be chosen by providing its name with the `.#` prefix, e.g. `nix develop .#gcc15`.
+A compiler can be chosen by providing its name with the `.#` prefix, e.g. `nix develop .#clang`.
+The `.#gcc` and `.#clang` shells provide the same GCC and Clang versions used in CI
+(pinned in [`nix/packages.nix`](../../nix/packages.nix)).
 Use `nix flake show` to see all the available development shells.
 
 Use `nix develop .#no-compiler` to use the compiler from your system.
@@ -70,11 +72,11 @@ Use `nix develop .#no-compiler` to use the compiler from your system.
 ### Example Usage
 
 ```bash
-# Use GCC 14
-nix develop .#gcc14
+# Use GCC (same version as CI)
+nix develop .#gcc
 
-# Use Clang 19
-nix develop .#clang19
+# Use Clang (same version as CI)
+nix develop .#clang
 
 # Use default for your platform
 nix develop
@@ -112,7 +114,15 @@ Once inside the Nix development shell, follow the standard [build instructions](
 
 [direnv](https://direnv.net/) or [nix-direnv](https://github.com/nix-community/nix-direnv) can automatically activate the Nix development shell when you enter the repository directory.
 
-This is also the most robust way to use the environment from **any shell** (bash, zsh, fish, …): direnv stays in your current shell and loads the environment _after_ your shell's startup files have run, so the Nix-provided tools take precedence over anything your shell configuration adds to `$PATH`. To use it, install direnv for your shell, then add an `.envrc` containing `use flake` at the repository root and run `direnv allow`.
+This is also the most robust way to use the environment from **any shell** (bash, zsh, fish, …): direnv stays in your current shell and loads the environment _after_ your shell's startup files have run, so the Nix-provided tools take precedence over anything your shell configuration adds to `$PATH`.
+
+The repository already ships an `.envrc` at its root that activates the Nix flake development shell, so you don't need to create one. To use it:
+
+1. [Install direnv](https://direnv.net/docs/installation.html) and [hook it into your shell](https://direnv.net/docs/hook.html) (bash, zsh, fish, …). Installing [nix-direnv](https://github.com/nix-community/nix-direnv) as well is recommended: it caches the shell so that activation is near-instant after the first run.
+2. Run `direnv allow` once in the repository root. direnv will then load (and reload) the Nix development shell automatically whenever you enter the directory.
+
+> [!NOTE]
+> direnv only caches the `.direnv` directory (already listed in `.gitignore`); no other repository files are affected.
 
 ## Conan and Prebuilt Packages
 

include/xrpl/basics/IntrusivePointer.ipp

@@ -641,6 +641,9 @@ template <class T>
 T*
 SharedWeakUnion<T>::unsafeGetRawPtr() const
 {
+    // tp_ packs a raw pointer together with a strength bit; recovering the
+    // pointer inherently requires an integer-to-pointer cast.
+    // NOLINTNEXTLINE(performance-no-int-to-ptr)
     return reinterpret_cast<T*>(tp_ & kPtrMask);
 }
 

include/xrpl/shamap/detail/TaggedPointer.ipp

@@ -507,6 +507,9 @@ TaggedPointer::operator=(TaggedPointer&& other)
 [[nodiscard]] inline std::pair<std::uint8_t, void*>
 TaggedPointer::decode() const
 {
+    // tp_ packs a raw pointer together with the tag bits; recovering the
+    // pointer inherently requires an integer-to-pointer cast.
+    // NOLINTNEXTLINE(performance-no-int-to-ptr)
     return {tp_ & kTagMask, reinterpret_cast<void*>(tp_ & kPtrMask)};
 }
 
@@ -535,6 +538,9 @@ TaggedPointer::getHashesAndChildren() const
 [[nodiscard]] inline SHAMapHash*
 TaggedPointer::getHashes() const
 {
+    // tp_ packs a raw pointer together with the tag bits; recovering the
+    // pointer inherently requires an integer-to-pointer cast.
+    // NOLINTNEXTLINE(performance-no-int-to-ptr)
     return reinterpret_cast<SHAMapHash*>(tp_ & kPtrMask);
 };
 

nix/ci-env.nix

@@ -4,14 +4,16 @@
   ...
 }:
 let
-  inherit (import ./packages.nix { inherit pkgs; }) commonPackages;
-  inherit (pkgs) lib;
+  inherit (import ./packages.nix { inherit pkgs; })
+    commonPackages
+    gccPackage
+    llvmPackages
+    llvmVersion
+    ;
 
-  # Underlying compiler toolchains to wrap. Bump these in one place to
-  # roll the whole environment forward.
-  customGccPackage = pkgs.gcc15;
-  customLlvmPackages = pkgs.llvmPackages_22;
-  customClangMajor = lib.versions.major (lib.getVersion customLlvmPackages.clang-unwrapped);
+  # Underlying compiler toolchains to wrap (versions pinned in packages.nix).
+  customGccPackage = gccPackage;
+  customLlvmPackages = llvmPackages;
 
   # binutils wrapped to emit binaries that reference the custom glibc
   # (dynamic linker path, library search path, RPATH).
@@ -90,7 +92,7 @@ let
     extraBuildCommands = ''
       rsrc="$out/resource-root"
       mkdir "$rsrc"
-      ln -s "${customLlvmPackages.clang-unwrapped.lib}/lib/clang/${customClangMajor}/include" "$rsrc/include"
+      ln -s "${customLlvmPackages.clang-unwrapped.lib}/lib/clang/${toString llvmVersion}/include" "$rsrc/include"
       ln -s "${customCompilerRt.out}/lib" "$rsrc/lib"
       ln -s "${customCompilerRt.out}/share" "$rsrc/share" || true
       echo "-resource-dir=$rsrc" >> $out/nix-support/cc-cflags

nix/devshell.nix

@@ -1,127 +1,57 @@
 { pkgs, ... }:
 let
-  inherit (import ./packages.nix { inherit pkgs; }) commonPackages;
+  inherit (import ./packages.nix { inherit pkgs; })
+    commonPackages
+    gccVersion
+    llvmPackages
+    ;
 
-  # Supported compiler versions
-  gccVersion = pkgs.lib.range 13 15;
-  clangVersions = pkgs.lib.range 18 21;
+  # Plain nixpkgs stdenvs — no custom glibc, unlike ci-env.nix.
+  gccStdenv = pkgs."gcc${toString gccVersion}Stdenv";
+  clangStdenv = llvmPackages.stdenv;
 
-  defaultCompiler = if pkgs.stdenv.isDarwin then "apple-clang" else "gcc";
-  defaultGccVersion = pkgs.lib.last gccVersion;
-  defaultClangVersion = pkgs.lib.last clangVersions;
-
-  strToCompilerEnv =
-    compiler: version:
-    (
-      if compiler == "gcc" then
-        let
-          gccPkg = pkgs."gcc${toString version}Stdenv" or null;
-        in
-        if gccPkg != null && builtins.elem version gccVersion then
-          gccPkg
-        else
-          throw "Invalid GCC version: ${toString version}. Must be one of: ${toString gccVersion}"
-      else if compiler == "clang" then
-        let
-          clangPkg = pkgs."llvmPackages_${toString version}".stdenv or null;
-        in
-        if clangPkg != null && builtins.elem version clangVersions then
-          clangPkg
-        else
-          throw "Invalid Clang version: ${toString version}. Must be one of: ${toString clangVersions}"
-      else if compiler == "apple-clang" || compiler == "none" then
-        pkgs.stdenvNoCC
-      else
-        throw "Invalid compiler: ${compiler}. Must be one of: gcc, clang, apple-clang, none"
-    );
-
-  # Helper function to create a shell with a specific compiler
+  # compilerName is the command used to print the version, or null for none.
   makeShell =
     {
-      compiler ? defaultCompiler,
-      version ? (
-        if compiler == "gcc" then
-          defaultGccVersion
-        else if compiler == "clang" then
-          defaultClangVersion
-        else
-          null
-      ),
+      stdenv,
+      compilerName,
     }:
     let
-      compilerStdEnv = strToCompilerEnv compiler version;
-
-      compilerName =
-        if compiler == "apple-clang" then
-          "clang"
-        else if compiler == "none" then
-          null
-        else
-          compiler;
-
-      gccOnMacWarning =
-        if pkgs.stdenv.isDarwin && compiler == "gcc" then
-          ''
-            echo "WARNING: Using GCC on macOS with Conan may not work."
-            echo "         Consider using 'nix develop .#clang' or the default shell instead."
-            echo ""
-          ''
-        else
-          "";
-
       compilerVersion =
-        if compilerName != null then
+        if compilerName == null then
+          ''echo "No compiler specified - using system compiler"''
+        else
           ''
             echo "Compiler: "
             ${compilerName} --version
-          ''
-        else
-          ''
-            echo "No compiler specified - using system compiler"
           '';
-
-      shellAttrs = {
-        packages = commonPackages;
-
-        shellHook = ''
-          echo "Welcome to xrpld development shell";
-          ${gccOnMacWarning}${compilerVersion}
-        '';
-      };
     in
-    pkgs.mkShell.override { stdenv = compilerStdEnv; } shellAttrs;
-
-  # Generate shells for each compiler version
-  gccShells = builtins.listToAttrs (
-    map (version: {
-      name = "gcc${toString version}";
-      value = makeShell {
-        compiler = "gcc";
-        version = version;
-      };
-    }) gccVersion
-  );
-
-  clangShells = builtins.listToAttrs (
-    map (version: {
-      name = "clang${toString version}";
-      value = makeShell {
-        compiler = "clang";
-        version = version;
-      };
-    }) clangVersions
-  );
-
+    (pkgs.mkShell.override { inherit stdenv; }) {
+      packages = commonPackages;
+      shellHook = ''
+        echo "Welcome to xrpld development shell";
+        ${compilerVersion}
+      '';
+    };
 in
-gccShells
-// clangShells
-// {
-  # Default shells
-  default = makeShell { };
-  gcc = makeShell { compiler = "gcc"; };
-  clang = makeShell { compiler = "clang"; };
+rec {
+  # macOS: Nix Clang. Linux: Nix GCC.
+  default = if pkgs.stdenv.isDarwin then clang else gcc;
 
-  # No compiler
-  no-compiler = makeShell { compiler = "none"; };
-  apple-clang = makeShell { compiler = "apple-clang"; };
+  gcc = makeShell {
+    stdenv = gccStdenv;
+    compilerName = "gcc";
+  };
+
+  clang = makeShell {
+    stdenv = clangStdenv;
+    compilerName = "clang";
+  };
+
+  # Nix provides no compiler; use the one from your system (e.g. Apple Clang).
+  no-compiler = makeShell {
+    stdenv = pkgs.stdenvNoCC;
+    compilerName = null;
+  };
+  apple-clang = no-compiler;
 }

nix/packages.nix

@@ -1,15 +1,33 @@
 { pkgs }:
 let
+  # Compiler versions used across the dev shell and the CI environment.
+  gccVersion = 15;
+  llvmVersion = 22;
+
+  gccPackage = pkgs."gcc${toString gccVersion}";
+  llvmPackages = pkgs."llvmPackages_${toString llvmVersion}";
+
+  # Bound explicitly so it tracks llvmPackages above, not the `with pkgs` default.
+  clangTools = llvmPackages.clang-tools;
+
   # In LLVM 22, run-clang-tidy.py moved from share/clang/ to bin/, so nixpkgs
   # clang-tools no longer links it. Wrap it manually.
   runClangTidy = pkgs.writeShellScriptBin "run-clang-tidy" ''
-    exec ${pkgs.python3}/bin/python3 ${pkgs.llvmPackages_22.clang-unwrapped}/bin/run-clang-tidy "$@"
+    exec ${pkgs.python3}/bin/python3 ${llvmPackages.clang-unwrapped}/bin/run-clang-tidy "$@"
   '';
 in
 {
+  inherit
+    gccVersion
+    llvmVersion
+    gccPackage
+    llvmPackages
+    ;
+
   commonPackages = with pkgs; [
     ccache
     clangbuildanalyzer
+    clangTools
     cmake
     conan
     curlMinimal # needed for codecov/codecov-action
@@ -23,7 +41,6 @@ in
     gnumake
     gnupg # needed for signing commits & codecov/codecov-action
     graphviz
-    llvmPackages_22.clang-tools
     less # needed for git diff
     mold
     nettools # provides netstat, used to debug failures in CI

src/libxrpl/json/json_reader.cpp

@@ -5,12 +5,13 @@
 
 #include <algorithm>
 #include <cctype>
+#include <charconv>
 #include <cstdint>
 #include <cstdio>
-#include <cstring>
 #include <istream>
 #include <stdexcept>
 #include <string>
+#include <system_error>
 
 namespace json {
 // Implementation of class Reader
@@ -605,36 +606,17 @@ bool
 Reader::decodeDouble(Token& token)
 {
     double value = 0;
-    int const bufferSize = 32;
-    int count = 0;
-    int const length = int(token.end - token.start);
-    // Sanity check to avoid buffer overflow exploits.
-    if (length < 0)
-    {
-        return addError("Unable to parse token length", token);
-    }
-    // Avoid using a string constant for the format control string given to
-    // sscanf, as this can cause hard to debug crashes on OS X. See here for
-    // more info:
-    //
-    // http://developer.apple.com/library/mac/#DOCUMENTATION/DeveloperTools/gcc-4.0.1/gcc/Incompatibilities.html
-    char format[] = "%lf";
-    if (length <= bufferSize)
-    {
-        Char buffer[bufferSize + 1];
-        memcpy(buffer, token.start, length);
-        buffer[length] = 0;
-        // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg)
-        count = sscanf(buffer, format, &value);
-    }
-    else
-    {
-        std::string const buffer(token.start, token.end);
-        // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg)
-        count = sscanf(buffer.c_str(), format, &value);
-    }
-    if (count != 1)
+    auto const [ptr, ec] = std::from_chars(token.start, token.end, value);
+
+    // Reject anything from_chars could not turn into a finite double:
+    //   - ec != std::errc{}: no valid conversion, or an out-of-range magnitude
+    //     (e.g. 1e400).
+    //   - ptr != token.end: readNumber() is permissive about which characters
+    //     it collects into a token (it will, for example, keep a '+' mid-token),
+    //     but from_chars() will stop at the first character it cannot parse.
+    if (ec != std::errc{} || ptr != token.end)
         return addError("'" + std::string(token.start, token.end) + "' is not a number.", token);
+
     currentValue() = value;
     return true;
 }

src/libxrpl/json/json_writer.cpp

@@ -4,13 +4,14 @@
 #include <xrpl/json/json_forwards.h>
 #include <xrpl/json/json_value.h>
 
-#include <cstdio>
+#include <charconv>
 #include <cstring>
 #include <iomanip>
 #include <ios>
 #include <ostream>
 #include <sstream>
 #include <string>
+#include <system_error>
 #include <utility>
 
 namespace json {
@@ -76,20 +77,18 @@ valueToString(UInt value)
 std::string
 valueToString(double value)
 {
-    // Allocate a buffer that is more than large enough to store the 16 digits
-    // of precision requested below.
+    // Format with 16 significant digits.
+    // We need not request the alternative representation that always has a
+    // decimal point because JSON doesn't distinguish the concepts of reals and integers.
+    // A double never needs more than 32 characters in this form,
+    // so to_chars cannot actually run out of room here.
     char buffer[32];
-    // Print into the buffer. We need not request the alternative representation
-    // that always has a decimal point because JSON doesn't distinguish the
-    // concepts of reals and integers.
-#if defined(_MSC_VER) && defined(__STDC_SECURE_LIB__)  // Use secure version with visual studio 2005
-                                                       // to avoid warning.
-    sprintf_s(buffer, sizeof(buffer), "%.16g", value);
-#else
-    // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg)
-    snprintf(buffer, sizeof(buffer), "%.16g", value);
-#endif
-    return buffer;
+    auto const [ptr, ec] =
+        std::to_chars(buffer, buffer + sizeof(buffer), value, std::chars_format::general, 16);
+    XRPL_ASSERT(ec == std::errc{}, "json::valueToString(double) : conversion fits buffer");
+    if (ec != std::errc{})
+        return {};
+    return std::string(buffer, ptr);
 }
 
 std::string

src/libxrpl/protocol/BuildInfo.cpp

@@ -23,7 +23,7 @@ namespace {
 //------------------------------------------------------------------------------
 // clang-format off
 // NOLINTNEXTLINE(readability-identifier-naming)
-char const* const versionString = "3.3.0-b0"
+char const* const versionString = "3.3.0-b1"
     // clang-format on
     ;
 

src/libxrpl/protocol/STParsedJSON.cpp

@@ -69,6 +69,17 @@ toUnsigned(U2 value)
     return static_cast<U1>(value);
 }
 
+static std::string
+joinName(std::string const& jsonName, std::string const& fieldName)
+{
+    std::string result;
+    result.reserve(jsonName.size() + 1 + fieldName.size());
+    result += jsonName;
+    result += '.';
+    result += fieldName;
+    return result;
+}
+
 // LCOV_EXCL_START
 static inline std::string
 makeName(std::string const& object, std::string const& field)
@@ -76,7 +87,7 @@ makeName(std::string const& object, std::string const& field)
     if (field.empty())
         return object;
 
-    return object + "." + field;
+    return joinName(object, field);
 }
 
 static inline json::Value
@@ -1036,8 +1047,8 @@ parseObject(
 
                     try
                     {
-                        auto ret =
-                            parseObject(jsonName + "." + fieldName, value, field, depth + 1, error);
+                        auto ret = parseObject(
+                            joinName(jsonName, fieldName), value, field, depth + 1, error);
                         if (!ret)
                             return std::nullopt;
                         data.emplaceBack(std::move(*ret));
@@ -1054,8 +1065,8 @@ parseObject(
                 case STI_ARRAY:
                     try
                     {
-                        auto array =
-                            parseArray(jsonName + "." + fieldName, value, field, depth + 1, error);
+                        auto array = parseArray(
+                            joinName(jsonName, fieldName), value, field, depth + 1, error);
                         if (!array.has_value())
                             return std::nullopt;
                         data.emplaceBack(std::move(*array));

src/libxrpl/rdb/SociDB.cpp

@@ -213,6 +213,12 @@ public:
         if (auto [conn, keepAlive] = getConnection(); conn)
         {
             (void)keepAlive;
+            // The checkpointer is identified to the C callback by an integer id
+            // (resolved via checkpointerFromId) rather than a raw `this`, so it
+            // cannot dangle if the checkpointer is destroyed. Passing the id
+            // through sqlite's void* user-data requires an integer-to-pointer
+            // cast.
+            // NOLINTNEXTLINE(performance-no-int-to-ptr)
             sqlite_api::sqlite3_wal_hook(conn, &sqliteWALHook, reinterpret_cast<void*>(id_));
         }
     }

src/test/app/Batch_test.cpp

@@ -498,7 +498,7 @@ class Batch_test : public beast::unit_test::Suite
             auto const batchFee = batch::calcBatchFee(env, 0, 2);
             auto tx1 = batch::Inner(pay(alice, bob, XRP(1)), seq + 1);
             tx1[jss::Fee] = "1.5";
-            env.setParseFailureExpected(true);
+            auto const g = env.getParseFailureGuard(true);
             try
             {
                 env(batch::outer(alice, seq, batchFee, tfAllOrNothing),
@@ -510,7 +510,6 @@ class Batch_test : public beast::unit_test::Suite
             {
                 BEAST_EXPECT(true);
             }
-            env.setParseFailureExpected(false);
         }
 
         // temSEQ_AND_TICKET: Batch: inner txn cannot have both Sequence

src/test/app/Vault_test.cpp

@@ -5451,9 +5451,9 @@ class Vault_test : public beast::unit_test::Suite
             env.close();
 
             // 2. Mantissa larger than uint64 max
-            env.setParseFailureExpected(true);
             try
             {
+                auto const g = env.getParseFailureGuard(true);
                 tx[sfAssetsMaximum] = "18446744073709551617e5";  // uint64 max + 1
                 env(tx);
                 BEAST_EXPECTS(false, "Expected parse_error for mantissa larger than uint64 max");
@@ -5464,7 +5464,6 @@ class Vault_test : public beast::unit_test::Suite
                 BEAST_EXPECT(
                     e.what() == "invalidParamsField 'tx_json.AssetsMaximum' has invalid data."s);
             }
-            env.setParseFailureExpected(false);
         }
     }
 

src/test/core/Config_test.cpp

@@ -1475,6 +1475,7 @@ r.ripple.com:51235
             std::string toLoad(R"xrpldConfig(
 [amendment_majority_time]
 )xrpldConfig");
+            // NOLINTNEXTLINE(performance-inefficient-string-concatenation)
             toLoad += std::to_string(val) + space + unit;
             space = space.empty() ? " " : "";
 

src/test/jtx/Env.h

@@ -495,6 +495,46 @@ public:
         parseFailureExpected_ = b;
     }
 
+    /** RAII class to set and restore the parse failure flag (setParseFailureExpected).
+     *
+     * Can be created directly, or through the `getParseFailureGuard(bool)` function.
+     */
+    class ParseFailureGuard final
+    {
+        Env& self_;
+        bool oldExpected_ = self_.parseFailureExpected_;
+
+    public:
+        ParseFailureGuard(Env& self, bool b) : self_(self)
+        {
+            self_.setParseFailureExpected(b);
+        }
+
+        ~ParseFailureGuard()
+        {
+            self_.setParseFailureExpected(oldExpected_);
+        }
+
+        // No copy, no move
+        ParseFailureGuard(ParseFailureGuard const&) = delete;
+        ParseFailureGuard&
+        operator=(ParseFailureGuard const&) = delete;
+        ParseFailureGuard(ParseFailureGuard&& other) = delete;
+        ParseFailureGuard&
+        operator=(ParseFailureGuard&&) = delete;
+    };
+
+    /** Gets an RAII guard to set and restore the parse failure flag
+     *
+     * Usage:
+     * auto const guard = env.getParseFailureGuard(true/false);
+     */
+    [[nodiscard]] ParseFailureGuard
+    getParseFailureGuard(bool b)
+    {
+        return ParseFailureGuard{*this, b};
+    }
+
     /** Turn off signature checks. */
     void
     disableSigs()

src/test/jtx/impl/Env.cpp

@@ -602,7 +602,7 @@ Env::autofill(JTx& jt)
     catch (ParseError const&)
     {
         if (!parseFailureExpected_)
-            test.log << "parse failed:\n" << pretty(jv) << std::endl;
+            test.log << "parse failure:\n" << pretty(jv) << std::endl;
         rethrow();
     }
 }

src/tests/libxrpl/json/Value.cpp

@@ -13,6 +13,7 @@
 #include <exception>
 #include <limits>
 #include <numbers>
+#include <optional>
 #include <regex>
 #include <sstream>
 #include <string>
@@ -592,6 +593,57 @@ TEST(json_value, bad_json)
     EXPECT_TRUE(r.parse(s, j));
 }
 
+namespace {
+
+std::optional<json::Value>
+parseValue(std::string const& doc)
+{
+    json::Value j;
+    json::Reader r;
+    if (!r.parse("{\"v\":" + doc + "}", j))
+        return std::nullopt;
+    return j["v"];
+}
+
+}  // namespace
+
+TEST(json_value, parse_double_valid)
+{
+    // 1e300 is large but still representable, so it parses (unlike the out-of-range cases below).
+    for (auto const& [text, expected] :
+         {std::pair{"2.5", 2.5},
+          std::pair{"-3.25e2", -325.0},
+          std::pair{"0.0", 0.0},
+          std::pair{"1E3", 1000.0},
+          std::pair{"-0.5e-1", -0.05},
+          std::pair{"1e300", 1e300}})
+    {
+        auto const v = parseValue(text);
+        ASSERT_TRUE(v.has_value()) << text;
+        // NOLINTBEGIN(bugprone-unchecked-optional-access)
+        EXPECT_TRUE(v->isDouble()) << text;
+        EXPECT_EQ(v->asDouble(), expected) << text;
+        // NOLINTEND(bugprone-unchecked-optional-access)
+    }
+}
+
+TEST(json_value, parse_double_out_of_range)
+{
+    // Magnitudes with no finite double representation are rejected.
+    for (char const* oor : {"1e400", "-1e400", "0.001e500", "1e-400", "-1e-400", "123e-500"})
+        EXPECT_FALSE(parseValue(oor).has_value()) << oor;
+}
+
+TEST(json_value, parse_double_malformed)
+{
+    // readNumber() collects any run of digits and '.eE+-' into a single Double
+    // token, so these malformed tokens reach decodeDouble. Each has a valid
+    // leading prefix that from_chars would accept on its own; requiring the
+    // entire token be consumed rejects them instead of silently truncating.
+    for (char const* bad : {"1+2", "1-2", "1.2.3", "1e5e6", "1..2", "++5", "1e", "1e+", ".", "-"})
+        EXPECT_FALSE(parseValue(bad).has_value()) << bad;
+}
+
 TEST(json_value, edge_cases)
 {
     std::uint32_t const maxUInt = std::numeric_limits<std::uint32_t>::max();