Rewrite the float-to-string conversion

Instead of committing to a number of decimal places, the new algorithm targets a certain number of significant digits.
Since the mantissa has to fit in a 32-bit integer, the number of significant digits is limited to 9.

.github/workflows/ci.yml

@@ -93,44 +93,40 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - clang: "3.9"
-            runner: ubuntu-20.04
-            archive: bionic
-          - clang: "4.0"
-            runner: ubuntu-20.04
-            archive: bionic
-          - clang: "5.0"
-            runner: ubuntu-20.04
-            archive: bionic
-          - clang: "6.0"
-            runner: ubuntu-20.04
-            archive: bionic
           - clang: "7"
-            runner: ubuntu-20.04
+            runner: ubuntu-22.04
+            archive: focal
           - clang: "8"
             cxxflags: -fsanitize=leak -fno-sanitize-recover=all
-            runner: ubuntu-20.04
+            runner: ubuntu-22.04
+            archive: focal
           - clang: "9"
             cxxflags: -fsanitize=undefined -fno-sanitize-recover=all
-            runner: ubuntu-20.04
+            runner: ubuntu-22.04
+            archive: focal
           - clang: "10"
             cxxflags: -fsanitize=address -fno-sanitize-recover=all
-            runner: ubuntu-20.04
+            runner: ubuntu-22.04
+            archive: focal
           - clang: "11"
             runner: ubuntu-22.04
           - clang: "12"
             runner: ubuntu-22.04
           - clang: "13"
             runner: ubuntu-22.04
-          - clang: "14"
-            runner: ubuntu-22.04
-          - clang: "15"
-            runner: ubuntu-22.04
-    runs-on: ${{ matrix.runner }}
+          - clang: 14
+          - clang: 15
+          - clang: 16
+          - clang: 17
+          - clang: 18
+          - clang: 19
+    runs-on: ${{ matrix.runner || 'ubuntu-latest' }}
     steps:
       - name: Add archive repositories
         if: matrix.archive
         run: |
+          sudo gpg --keyserver keyserver.ubuntu.com --recv-keys 3B4FE6ACC0B21F32
+          sudo gpg --export 3B4FE6ACC0B21F32 | sudo tee /etc/apt/trusted.gpg.d/ubuntu-keyring.gpg > /dev/null
           sudo add-apt-repository -yn 'deb http://archive.ubuntu.com/ubuntu/ ${{ matrix.archive }} main'
           sudo add-apt-repository -yn 'deb http://archive.ubuntu.com/ubuntu/ ${{ matrix.archive }} universe'
       - name: Install Clang ${{ matrix.clang }}
@@ -138,10 +134,9 @@ jobs:
           sudo apt-get update
           sudo apt-get install -y clang-${{ matrix.clang }}
       - name: Install libc++ ${{ matrix.clang }}
-        if: matrix.clang >= 11
         run: sudo apt-get install -y libc++-${{ matrix.clang }}-dev libc++abi-${{ matrix.clang }}-dev
       - name: Install libunwind ${{ matrix.clang }}
-        if: matrix.clang == 12  # dependency is missing in Ubuntu 22.04
+        if: matrix.clang == 12 # dependency is missing in Ubuntu 22.04
         run: sudo apt-get install -y libunwind-${{ matrix.clang }}-dev
       - name: Checkout
         uses: actions/checkout@v4
@@ -163,7 +158,7 @@ jobs:
   conf_test:
     name: Test configuration on Linux
     needs: [gcc, clang]
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Install
         run: |
@@ -184,19 +179,19 @@ jobs:
 
   conf_test_windows:
     name: Test configuration on Windows
-    runs-on: windows-2019
+    runs-on: windows-2022
     needs: [gcc, clang]
     steps:
       - name: Checkout
         uses: actions/checkout@v4
       - name: 32-bit
         run: |
-          call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Auxiliary\Build\vcvars32.bat"
+          call "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars32.bat"
           cl /Isrc extras/conf_test/x86.cpp
         shell: cmd
       - name: 64-bit
         run: |
-          call "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
+          call "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
           cl /Isrc extras/conf_test/x64.cpp
         shell: cmd
 
@@ -257,7 +252,7 @@ jobs:
             board: arduino:avr:uno
           - core: arduino:samd
             board: arduino:samd:mkr1000
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -403,7 +398,9 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Install Particle CLI
-        run: sudo npm install -g particle-cli particle-usb
+        run: |
+          bash <( curl -sL https://particle.io/install-cli )
+          echo "$HOME/bin" >> $GITHUB_PATH
       - name: Login to Particle
         run: particle login -t "${{ secrets.PARTICLE_TOKEN }}"
       - name: Compile
@@ -412,7 +409,7 @@ jobs:
   arm:
     name: GCC for ARM processor
     needs: gcc
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Install
         run: |
@@ -431,7 +428,7 @@ jobs:
   coverage:
     needs: gcc
     name: Coverage
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Install
         run: sudo apt-get install -y lcov ninja-build
@@ -463,7 +460,7 @@ jobs:
   valgrind:
     needs: gcc
     name: Valgrind
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Install
         run: |
@@ -485,24 +482,24 @@ jobs:
   clang-tidy:
     needs: clang
     name: Clang-Tidy
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
       - name: Install
-        run: sudo apt-get install -y clang-tidy cmake ninja-build
+        run: sudo apt-get install -y clang-tidy libc++-dev libc++abi-dev
       - name: Checkout
         uses: actions/checkout@v4
       - name: Configure
-        run: cmake -G Ninja -DCMAKE_CXX_CLANG_TIDY="clang-tidy-10;--warnings-as-errors=*" -DCMAKE_BUILD_TYPE=Debug .
+        run: cmake -G Ninja -DCMAKE_CXX_CLANG_TIDY="clang-tidy;--warnings-as-errors=*" -DCMAKE_BUILD_TYPE=Debug .
         env:
-          CC: clang-10
-          CXX: clang++-10
+          CC: clang
+          CXX: clang++
       - name: Check
         run: cmake --build . -- -k 0
 
   amalgamate:
     needs: gcc
     name: Amalgamate ArduinoJson.h
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -578,7 +575,7 @@ jobs:
 
   codeql:
     name: CodeQL
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     needs: gcc
 
     permissions:
@@ -587,20 +584,20 @@ jobs:
       security-events: write
 
     steps:
-    - name: Checkout repository
-      uses: actions/checkout@v4
+      - name: Checkout repository
+        uses: actions/checkout@v4
 
-    - name: Initialize CodeQL
-      uses: github/codeql-action/init@v3
-      with:
-        languages: cpp
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: cpp
 
-    - name: Build
-      run: |
-        cmake -DCMAKE_BUILD_TYPE=Debug .
-        cmake --build .
+      - name: Build
+        run: |
+          cmake -DCMAKE_BUILD_TYPE=Debug .
+          cmake --build .
 
-    - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v3
-      with:
-        category: "/language:cpp"
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3
+        with:
+          category: "/language:cpp"

.github/workflows/release.yml

@@ -8,7 +8,7 @@ on:
 jobs:
   release:
     name: Create release
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
       - name: Set variables
         id: init
@@ -21,7 +21,13 @@ jobs:
         id: body
         run: |
           FILENAME=RELEASE.md
-          extras/scripts/get-release-body.sh ${{ steps.init.outputs.tag }} CHANGELOG.md | tee $FILENAME
+          tee $FILENAME <<END
+          ## Changes
+
+          $(extras/scripts/extract_changes.awk CHANGELOG.md)
+
+          [View version history](https://github.com/bblanchon/ArduinoJson/blob/${{ steps.init.outputs.tag }}/CHANGELOG.md)
+          END
           echo "filename=$FILENAME" >> $GITHUB_OUTPUT
       - name: Amalgamate ArduinoJson.h
         id: amalgamate_h
@@ -61,7 +67,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Install
-        run: npm install -g particle-cli particle-usb
+        run: npm install -g particle-cli
       - name: Checkout
         uses: actions/checkout@v4
       - name: Login

ArduinoJson.h

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include "src/ArduinoJson.h"

CHANGELOG.md

@@ -1,6 +1,145 @@
 ArduinoJson: change log
 =======================
 
+HEAD
+----
+
+* Don't store string literals by pointer anymore (issue #2189)
+  Version 7.3 introduced a new way to detect string literals, but it fails in some edge cases.
+  I could not find a way to fix it, so I chose to remove the optimization rather than keep it broken.
+* Replace the "extension slots" mechanism with a memory pool dedicated to 8-byte values.
+
+> ### BREAKING CHANGES
+>
+> #### `JsonString` constructor's boolean parameter
+>
+> Since version 7.3, you could pass a boolean to `JsonString`'s constructor to force the string to be stored by pointer.
+> This optimization has been removed, and you'll get a deprecation warning if you use it.
+> To fix the issue, you must remove the boolean argument from the constructor, or better yet, remove `JsonString` altogether.
+>
+> ```diff
+>   char name[] = "ArduinoJson";
+> - doc["name"] = JsonString(name, true);
+> + doc["name"] = name;
+> ```
+>
+> #### NUL characters in string literals
+> 
+> Since version 7.3, ArduinoJson has supported NUL characters (`\0`) in string literals.
+> This feature has been removed as part of the storage policy change.
+>
+> If you do need to include NULs in your string, you must use a `JsonString` instead:
+>
+> ```diff
+> - doc["strings"] = "hello\0world"
+> + doc["strings"] = JsonString("hello\0world", 11)
+> ```
+
+v7.4.2 (2025-06-20)
+------
+
+* Fix truncated strings on Arduino Due (issue #2181)
+
+v7.4.1 (2025-04-11)
+------
+
+* Fix crash with tiny Flash strings (issue #2170)
+
+v7.4.0 (2025-04-09)
+------
+
+* Optimize storage of tiny strings (up to 3 characters)
+* Fix support for `const char[]` (issue #2166)
+
+v7.3.1 (2025-02-27)
+------
+
+* Fix conversion from static string to number
+* Slightly reduce code size
+
+v7.3.0 (2024-12-29)
+------
+
+* Fix support for NUL characters in `deserializeJson()`
+* Make `ElementProxy` and `MemberProxy` non-copyable
+* Change string copy policy: only string literal are stored by pointer
+* `JsonString` is now stored by copy, unless specified otherwise
+* Replace undocumented `JsonString::Ownership` with `bool`
+* Rename undocumented `JsonString::isLinked()` to `isStatic()`
+* Move public facing SFINAEs to template declarations
+
+> ### BREAKING CHANGES
+>
+> In previous versions, `MemberProxy` (the class returned by `operator[]`) could lead to dangling pointers when used with a temporary string.
+> To prevent this issue, `MemberProxy` and `ElementProxy` are now non-copyable.
+>
+> Your code is likely to be affected if you use `auto` to store the result of `operator[]`. For example, the following line won't compile anymore:
+>
+> ```cpp
+> auto value = doc["key"];
+> ```
+>
+> To fix the issue, you must append either `.as<T>()` or `.to<T>()`, depending on the situation.
+>
+> For example, if you are extracting values from a JSON document, you should update like this:
+>
+> ```diff
+> - auto config = doc["config"];
+> + auto config = doc["config"].as<JsonObject>();
+> const char* name = config["name"];
+> ```
+>
+> However, if you are building a JSON document, you should update like this:
+>
+> ```diff
+> - auto config = doc["config"];
+> + auto config = doc["config"].to<JsonObject>();
+> config["name"] = "ArduinoJson";
+> ```
+
+v7.2.1 (2024-11-15)
+------
+
+* Forbid `deserializeJson(JsonArray|JsonObject, ...)` (issue #2135)
+* Fix VLA support in `JsonDocument::set()`
+* Fix `operator[](variant)` ignoring NUL characters
+
+v7.2.0 (2024-09-18)
+------
+
+* Store object members with two slots: one for the key and one for the value
+* Store 64-bit numbers (`double` and `long long`) in an additional slot
+* Reduce the slot size (see table below)
+* Improve message when user forgets third arg of `serializeJson()` et al.
+* Set `ARDUINOJSON_USE_DOUBLE` to `0` by default on 8-bit architectures
+* Deprecate `containsKey()` in favor of `doc["key"].is<T>()`
+* Add support for escape sequence `\'` (issue #2124)
+
+| Architecture | before   | after    |
+|--------------|----------|----------|
+| 8-bit        | 8 bytes  | 6 bytes  |
+| 32-bit       | 16 bytes | 8 bytes  |
+| 64-bit       | 24 bytes | 16 bytes |
+
+> ### BREAKING CHANGES
+>
+> After being on the death row for years, the `containsKey()` method has finally been deprecated.
+> You should replace `doc.containsKey("key")` with `doc["key"].is<T>()`, which not only checks that the key exists but also that the value is of the expected type.
+>
+> ```cpp
+> // Before
+> if (doc.containsKey("value")) {
+>   int value = doc["value"];
+>   // ...
+> }
+>
+> // After
+> if (doc["value"].is<int>()) {
+>   int value = doc["value"];
+>   // ...
+> }
+> ```
+
 v7.1.0 (2024-06-27)
 ------
 

CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 cmake_minimum_required(VERSION 3.15)
@@ -10,7 +10,7 @@ if(ESP_PLATFORM)
 	return()
 endif()
 
-project(ArduinoJson VERSION 7.1.0)
+project(ArduinoJson VERSION 7.4.2)
 
 if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
 	include(CTest)

LICENSE.txt

@@ -1,7 +1,7 @@
 The MIT License (MIT)
 ---------------------
 
-Copyright © 2014-2024, Benoit BLANCHON
+Copyright © 2014-2025, Benoit BLANCHON
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 

README.md

@@ -80,7 +80,7 @@ ArduinoJson is a C++ JSON library for Arduino and IoT (Internet Of Things).
     * Continuously tested on
         * [Visual Studio 2017, 2019, 2022](https://ci.appveyor.com/project/bblanchon/arduinojson/branch/7.x)
         * [GCC 4.8, 5, 6, 7, 8, 9, 10, 11, 12](https://github.com/bblanchon/ArduinoJson/actions?query=workflow%3A%22Continuous+Integration%22)
-        * [Clang 3.9, 4.0, 5.0, 6.0, 7, 8, 9, 10, 11, 12, 13, 14, 15](https://github.com/bblanchon/ArduinoJson/actions?query=workflow%3A%22Continuous+Integration%22)
+        * [Clang 7 to 19](https://github.com/bblanchon/ArduinoJson/actions?query=workflow%3A%22Continuous+Integration%22)
     * [Continuously fuzzed with Google OSS Fuzz](https://bugs.chromium.org/p/oss-fuzz/issues/list?sort=-opened&can=1&q=proj:arduinojson)
     * Passes all default checks of [clang-tidy](https://releases.llvm.org/10.0.0/tools/clang/tools/extra/docs/clang-tidy/)
 * Well documented
@@ -139,15 +139,13 @@ See the [tutorial on arduinojson.org](https://arduinojson.org/v7/doc/serializati
 
 ArduinoJson is thankful to its sponsors. Please give them a visit; they deserve it!
 
-<p>
-  <a href="https://www.programmingelectronics.com/" rel="sponsored">
-    <img src="https://arduinojson.org/images/2021/10/programmingeleactronicsacademy.png" alt="Programming Electronics Academy" width="200">
-  </a>
-</p>
 <p>
   <a href="https://github.com/1technophile" rel="sponsored">
     <img alt="1technophile" src="https://avatars.githubusercontent.com/u/12672732?s=40&v=4">
   </a>
+  <a href="https://github.com/LArkema" rel="sponsored">
+    <img alt="LArkema" src="https://avatars.githubusercontent.com/u/38381313?s=40&v=4">
+  </a>
 </p>
 
 If you run a commercial project that embeds ArduinoJson, think about [sponsoring the library's development](https://github.com/sponsors/bblanchon): it ensures the code that your products rely on stays actively maintained. It can also give your project some exposure to the makers' community.

appveyor.yml

@@ -1,4 +1,4 @@
-version: 7.1.0.{build}
+version: 7.4.2.{build}
 environment:
   matrix:
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022

examples/JsonConfigFile/JsonConfigFile.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to store your project configuration in a file.

examples/JsonFilterExample/JsonFilterExample.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to use DeserializationOption::Filter

examples/JsonGeneratorExample/JsonGeneratorExample.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to generate a JSON document with ArduinoJson.

examples/JsonHttpClient/JsonHttpClient.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to parse a JSON document in an HTTP response.

examples/JsonParserExample/JsonParserExample.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to deserialize a JSON document with ArduinoJson.

examples/JsonServer/JsonServer.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to implement an HTTP server that sends a JSON document

examples/JsonUdpBeacon/JsonUdpBeacon.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to send a JSON document to a UDP socket.

examples/MsgPackParser/MsgPackParser.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to deserialize a MessagePack document with

examples/ProgmemExample/ProgmemExample.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows the different ways you can use Flash strings with

examples/StringExample/StringExample.ino

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows the different ways you can use String with ArduinoJson.

extras/ci/espidf/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 cmake_minimum_required(VERSION 3.5)

extras/ci/espidf/main/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 idf_component_register(

extras/ci/espidf/main/main.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/conf_test/avr.cpp

@@ -6,12 +6,13 @@ static_assert(ARDUINOJSON_USE_LONG_LONG == 0, "ARDUINOJSON_USE_LONG_LONG");
 
 static_assert(ARDUINOJSON_SLOT_ID_SIZE == 1, "ARDUINOJSON_SLOT_ID_SIZE");
 
+static_assert(ARDUINOJSON_POOL_CAPACITY == 16, "ARDUINOJSON_POOL_CAPACITY");
+
 static_assert(ARDUINOJSON_LITTLE_ENDIAN == 1, "ARDUINOJSON_LITTLE_ENDIAN");
 
-static_assert(ARDUINOJSON_USE_DOUBLE == 1, "ARDUINOJSON_USE_DOUBLE");
+static_assert(ARDUINOJSON_USE_DOUBLE == 0, "ARDUINOJSON_USE_DOUBLE");
 
-static_assert(sizeof(ArduinoJson::detail::VariantSlot) == 8,
-              "sizeof(VariantSlot)");
+static_assert(sizeof(ArduinoJson::detail::VariantData) == 6, "slot size");
 
 void setup() {}
 void loop() {}

extras/conf_test/esp8266.cpp

@@ -4,12 +4,13 @@ static_assert(ARDUINOJSON_USE_LONG_LONG == 1, "ARDUINOJSON_USE_LONG_LONG");
 
 static_assert(ARDUINOJSON_SLOT_ID_SIZE == 2, "ARDUINOJSON_SLOT_ID_SIZE");
 
+static_assert(ARDUINOJSON_POOL_CAPACITY == 128, "ARDUINOJSON_POOL_CAPACITY");
+
 static_assert(ARDUINOJSON_LITTLE_ENDIAN == 1, "ARDUINOJSON_LITTLE_ENDIAN");
 
 static_assert(ARDUINOJSON_USE_DOUBLE == 1, "ARDUINOJSON_USE_DOUBLE");
 
-static_assert(sizeof(ArduinoJson::detail::VariantSlot) == 16,
-              "sizeof(VariantSlot)");
+static_assert(sizeof(ArduinoJson::detail::VariantData) == 8, "slot size");
 
 void setup() {}
 void loop() {}

extras/conf_test/x64.cpp

@@ -4,11 +4,12 @@ static_assert(ARDUINOJSON_USE_LONG_LONG == 1, "ARDUINOJSON_USE_LONG_LONG");
 
 static_assert(ARDUINOJSON_SLOT_ID_SIZE == 4, "ARDUINOJSON_SLOT_ID_SIZE");
 
+static_assert(ARDUINOJSON_POOL_CAPACITY == 256, "ARDUINOJSON_POOL_CAPACITY");
+
 static_assert(ARDUINOJSON_LITTLE_ENDIAN == 1, "ARDUINOJSON_LITTLE_ENDIAN");
 
 static_assert(ARDUINOJSON_USE_DOUBLE == 1, "ARDUINOJSON_USE_DOUBLE");
 
-static_assert(sizeof(ArduinoJson::detail::VariantSlot) == 24,
-              "sizeof(VariantSlot)");
+static_assert(sizeof(ArduinoJson::detail::VariantData) == 16, "slot size");
 
 int main() {}

extras/conf_test/x86.cpp

@@ -4,11 +4,12 @@ static_assert(ARDUINOJSON_USE_LONG_LONG == 1, "ARDUINOJSON_USE_LONG_LONG");
 
 static_assert(ARDUINOJSON_SLOT_ID_SIZE == 2, "ARDUINOJSON_SLOT_ID_SIZE");
 
+static_assert(ARDUINOJSON_POOL_CAPACITY == 128, "ARDUINOJSON_POOL_CAPACITY");
+
 static_assert(ARDUINOJSON_LITTLE_ENDIAN == 1, "ARDUINOJSON_LITTLE_ENDIAN");
 
 static_assert(ARDUINOJSON_USE_DOUBLE == 1, "ARDUINOJSON_USE_DOUBLE");
 
-static_assert(sizeof(ArduinoJson::detail::VariantSlot) == 16,
-              "sizeof(VariantSlot)");
+static_assert(sizeof(ArduinoJson::detail::VariantData) == 8, "slot size");
 
 int main() {}

extras/fuzzing/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 set(CMAKE_CXX_STANDARD 11)

extras/fuzzing/reproducer.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 // This file is NOT use by Google's OSS fuzz

extras/scripts/extract_changes.awk

@@ -0,0 +1,29 @@
+#!/usr/bin/awk -f
+
+# Start echoing after the first list item
+/\* / {
+    STARTED=1
+    EMPTY_LINE=0
+}
+
+# Remember if we have seen an empty line
+/^[[:space:]]*$/ {
+    EMPTY_LINE=1
+}
+
+# Exit when seeing a new version number
+/^v[[:digit:]]/ {
+    if (STARTED) exit
+}
+
+# Print if the line is not empty
+# and restore the empty line we have skipped
+!/^[[:space:]]*$/ {
+    if (STARTED) {
+        if (EMPTY_LINE) {
+            print ""
+            EMPTY_LINE=0
+        }
+        print
+    }
+}

extras/scripts/get-release-body.sh

@@ -1,14 +0,0 @@
-#!/bin/bash
-
-set -eu
-
-TAG="$1"
-CHANGELOG="$2"
-
-cat << END
-## Changes
-
-$(awk '/\* /{ FOUND=1 } /^[[:space:]]*$/ { if(FOUND) exit } { if(FOUND) print }' "$CHANGELOG")
-
-[View version history](https://github.com/bblanchon/ArduinoJson/blob/$TAG/CHANGELOG.md)
-END

extras/scripts/get-release-page.sh

@@ -14,5 +14,5 @@ date: '$(date +'%Y-%m-%d')'
 $(extras/scripts/wandbox/publish.sh "$ARDUINOJSON_H")
 ---
 
-$(awk '/\* /{ FOUND=1; print; next } { if (FOUND) exit}' "$CHANGELOG")
+$(extras/scripts/extract_changes.awk "$CHANGELOG")
 END

extras/scripts/wandbox/JsonGeneratorExample.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to generate a JSON document with ArduinoJson.

extras/scripts/wandbox/JsonParserExample.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to deserialize a JSON document with ArduinoJson.

extras/scripts/wandbox/MsgPackParserExample.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 //
 // This example shows how to generate a JSON document with ArduinoJson.

extras/scripts/wandbox/publish.sh

@@ -15,7 +15,7 @@ compile() {
   "code":$(read_string "$FILE_PATH"),
   "codes": [{"file":"ArduinoJson.h","code":$(read_string "$ARDUINOJSON_H")}],
   "options": "warning,c++11",
-  "compiler": "gcc-5.5.0",
+  "compiler": "gcc-head",
   "save": true
 }
 END

extras/tests/CMakeLists.txt

@@ -1,19 +1,22 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 set(CMAKE_CXX_STANDARD 11)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-add_subdirectory(catch)
+link_libraries(ArduinoJson)
 
-link_libraries(ArduinoJson catch)
+# Failing builds should only link with ArduinoJson, not catch
+add_subdirectory(FailingBuilds)
+
+add_subdirectory(catch)
+link_libraries(catch)
 
 include_directories(Helpers)
 add_subdirectory(Cpp17)
 add_subdirectory(Cpp20)
 add_subdirectory(Deprecated)
-add_subdirectory(FailingBuilds)
 add_subdirectory(IntegrationTests)
 add_subdirectory(JsonArray)
 add_subdirectory(JsonArrayConst)

extras/tests/Cpp17/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 if(MSVC_VERSION LESS 1910)

extras/tests/Cpp17/string_view.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 // we expect ArduinoJson.h to include <string_view>

extras/tests/Cpp20/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 if(MSVC_VERSION LESS 1910)

extras/tests/Deprecated/BasicJsonDocument.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>
@@ -46,7 +46,7 @@ TEST_CASE("BasicJsonDocument") {
     deserializeJson(doc, "{\"hello\":\"world\"}");
     REQUIRE(doc.as<std::string>() == "{\"hello\":\"world\"}");
     doc.clear();
-    REQUIRE(allocatorLog == "ARAARDDD");
+    REQUIRE(allocatorLog == "AARARDDD");
   }
 
   SECTION("copy") {
@@ -54,7 +54,7 @@ TEST_CASE("BasicJsonDocument") {
     doc["hello"] = "world";
     auto copy = doc;
     REQUIRE(copy.as<std::string>() == "{\"hello\":\"world\"}");
-    REQUIRE(allocatorLog == "AA");
+    REQUIRE(allocatorLog == "AAAAAA");
   }
 
   SECTION("capacity") {

extras/tests/Deprecated/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 if(CMAKE_CXX_COMPILER_ID MATCHES "(GNU|Clang)")
@@ -16,9 +16,10 @@ endif()
 
 add_executable(DeprecatedTests
 	add.cpp
+	BasicJsonDocument.cpp
+	containsKey.cpp
 	createNestedArray.cpp
 	createNestedObject.cpp
-	BasicJsonDocument.cpp
 	DynamicJsonDocument.cpp
 	macros.cpp
 	memoryUsage.cpp

extras/tests/Deprecated/DynamicJsonDocument.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/Deprecated/StaticJsonDocument.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/Deprecated/add.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/Deprecated/containsKey.cpp

@@ -0,0 +1,246 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright © 2014-2025, Benoit BLANCHON
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+#include "Literals.hpp"
+
+TEST_CASE("JsonDocument::containsKey()") {
+  JsonDocument doc;
+
+  SECTION("returns true on object") {
+    doc["hello"] = "world";
+
+    REQUIRE(doc.containsKey("hello") == true);
+  }
+
+  SECTION("returns true when value is null") {
+    doc["hello"] = static_cast<const char*>(0);
+
+    REQUIRE(doc.containsKey("hello") == true);
+  }
+
+  SECTION("returns true when key is a std::string") {
+    doc["hello"] = "world";
+
+    REQUIRE(doc.containsKey("hello"_s) == true);
+  }
+
+  SECTION("returns false  on object") {
+    doc["world"] = "hello";
+
+    REQUIRE(doc.containsKey("hello") == false);
+  }
+
+  SECTION("returns false on array") {
+    doc.add("hello");
+
+    REQUIRE(doc.containsKey("hello") == false);
+  }
+
+  SECTION("returns false on null") {
+    REQUIRE(doc.containsKey("hello") == false);
+  }
+
+  SECTION("supports JsonVariant") {
+    doc["hello"] = "world";
+    doc["key"] = "hello";
+
+    REQUIRE(doc.containsKey(doc["key"]) == true);
+    REQUIRE(doc.containsKey(doc["foo"]) == false);
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("supports VLAs") {
+    size_t i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    doc["hello"] = "world";
+
+    REQUIRE(doc.containsKey(vla) == true);
+  }
+#endif
+}
+
+TEST_CASE("MemberProxy::containsKey()") {
+  JsonDocument doc;
+  const auto& mp = doc["hello"];
+
+  SECTION("containsKey(const char*)") {
+    mp["key"] = "value";
+
+    REQUIRE(mp.containsKey("key") == true);
+    REQUIRE(mp.containsKey("key") == true);
+  }
+
+  SECTION("containsKey(std::string)") {
+    mp["key"] = "value";
+
+    REQUIRE(mp.containsKey("key"_s) == true);
+    REQUIRE(mp.containsKey("key"_s) == true);
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("supports VLAs") {
+    size_t i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    mp["hello"] = "world";
+
+    REQUIRE(mp.containsKey(vla) == true);
+  }
+#endif
+}
+
+TEST_CASE("JsonObject::containsKey()") {
+  JsonDocument doc;
+  JsonObject obj = doc.to<JsonObject>();
+  obj["hello"] = 42;
+
+  SECTION("returns true only if key is present") {
+    REQUIRE(false == obj.containsKey("world"));
+    REQUIRE(true == obj.containsKey("hello"));
+  }
+
+  SECTION("returns false after remove()") {
+    obj.remove("hello");
+
+    REQUIRE(false == obj.containsKey("hello"));
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("key is a VLA") {
+    size_t i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    REQUIRE(true == obj.containsKey(vla));
+  }
+#endif
+
+  SECTION("key is a JsonVariant") {
+    doc["key"] = "hello";
+    REQUIRE(true == obj.containsKey(obj["key"]));
+    REQUIRE(false == obj.containsKey(obj["hello"]));
+  }
+
+  SECTION("std::string") {
+    REQUIRE(true == obj.containsKey("hello"_s));
+  }
+
+  SECTION("unsigned char[]") {
+    unsigned char key[] = "hello";
+    REQUIRE(true == obj.containsKey(key));
+  }
+}
+
+TEST_CASE("JsonObjectConst::containsKey()") {
+  JsonDocument doc;
+  doc["hello"] = 42;
+  auto obj = doc.as<JsonObjectConst>();
+
+  SECTION("supports const char*") {
+    REQUIRE(false == obj.containsKey("world"));
+    REQUIRE(true == obj.containsKey("hello"));
+  }
+
+  SECTION("supports std::string") {
+    REQUIRE(false == obj.containsKey("world"_s));
+    REQUIRE(true == obj.containsKey("hello"_s));
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("supports VLA") {
+    size_t i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    REQUIRE(true == obj.containsKey(vla));
+  }
+#endif
+
+  SECTION("supports JsonVariant") {
+    doc["key"] = "hello";
+    REQUIRE(true == obj.containsKey(obj["key"]));
+    REQUIRE(false == obj.containsKey(obj["hello"]));
+  }
+}
+
+TEST_CASE("JsonVariant::containsKey()") {
+  JsonDocument doc;
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("returns false is unbound") {
+    CHECK_FALSE(JsonVariant().containsKey("hello"));
+  }
+
+  SECTION("containsKey(const char*)") {
+    var["hello"] = "world";
+
+    REQUIRE(var.containsKey("hello") == true);
+    REQUIRE(var.containsKey("world") == false);
+  }
+
+  SECTION("containsKey(std::string)") {
+    var["hello"] = "world";
+
+    REQUIRE(var.containsKey("hello"_s) == true);
+    REQUIRE(var.containsKey("world"_s) == false);
+  }
+
+  SECTION("containsKey(JsonVariant)") {
+    var["hello"] = "world";
+    var["key"] = "hello";
+
+    REQUIRE(var.containsKey(doc["key"]) == true);
+    REQUIRE(var.containsKey(doc["foo"]) == false);
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("supports VLAs") {
+    size_t i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    var["hello"] = "world";
+
+    REQUIRE(var.containsKey(vla) == true);
+  }
+#endif
+}
+
+TEST_CASE("JsonVariantConst::containsKey()") {
+  JsonDocument doc;
+  doc["hello"] = "world";
+  JsonVariantConst var = doc.as<JsonVariant>();
+
+  SECTION("support const char*") {
+    REQUIRE(var.containsKey("hello") == true);
+    REQUIRE(var.containsKey("world") == false);
+  }
+
+  SECTION("support std::string") {
+    REQUIRE(var.containsKey("hello"_s) == true);
+    REQUIRE(var.containsKey("world"_s) == false);
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("supports VLA") {
+    size_t i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    REQUIRE(true == var.containsKey(vla));
+  }
+#endif
+
+  SECTION("support JsonVariant") {
+    doc["key"] = "hello";
+    REQUIRE(var.containsKey(var["key"]) == true);
+    REQUIRE(var.containsKey(var["foo"]) == false);
+  }
+}

extras/tests/Deprecated/createNestedArray.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/Deprecated/createNestedObject.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/Deprecated/macros.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/Deprecated/memoryUsage.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/Deprecated/shallowCopy.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/FailingBuilds/CMakeLists.txt

@@ -1,8 +1,12 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
-macro(build_should_fail target)
+macro(add_failing_build source_file)
+	get_filename_component(target ${source_file} NAME_WE)
+
+	add_executable(${target} ${source_file})
+
 	set_target_properties(${target}
 		PROPERTIES
 			EXCLUDE_FROM_ALL TRUE
@@ -16,21 +20,13 @@ macro(build_should_fail target)
 	set_tests_properties(${target}
 		PROPERTIES
 			WILL_FAIL TRUE
-			LABELS "WillFail;Catch"
+			LABELS "WillFail"
 	)
 endmacro()
 
-add_executable(Issue978 Issue978.cpp)
-build_should_fail(Issue978)
-
-add_executable(read_long_long read_long_long.cpp)
-build_should_fail(read_long_long)
-
-add_executable(write_long_long write_long_long.cpp)
-build_should_fail(write_long_long)
-
-add_executable(variant_as_char variant_as_char.cpp)
-build_should_fail(variant_as_char)
-
-add_executable(assign_char assign_char.cpp)
-build_should_fail(assign_char)
+add_failing_build(Issue978.cpp)
+add_failing_build(read_long_long.cpp)
+add_failing_build(write_long_long.cpp)
+add_failing_build(variant_as_char.cpp)
+add_failing_build(assign_char.cpp)
+add_failing_build(deserialize_object.cpp)

extras/tests/FailingBuilds/Issue978.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/FailingBuilds/assign_char.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/FailingBuilds/deserialize_object.cpp

@@ -0,0 +1,12 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright © 2014-2025, Benoit BLANCHON
+// MIT License
+
+#include <ArduinoJson.h>
+
+// See issue #2135
+
+int main() {
+  JsonObject obj;
+  deserializeJson(obj, "");
+}

extras/tests/FailingBuilds/read_long_long.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #define ARDUINOJSON_USE_LONG_LONG 0

extras/tests/FailingBuilds/variant_as_char.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/FailingBuilds/write_long_long.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #define ARDUINOJSON_USE_LONG_LONG 0

extras/tests/Helpers/Allocators.hpp

@@ -1,12 +1,12 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once
 
 #include <ArduinoJson/Memory/Allocator.hpp>
+#include <ArduinoJson/Memory/MemoryPool.hpp>
 #include <ArduinoJson/Memory/StringBuilder.hpp>
-#include <ArduinoJson/Memory/VariantPool.hpp>
 
 #include <sstream>
 
@@ -265,12 +265,14 @@ class TimebombAllocator : public ArduinoJson::Allocator {
 }  // namespace
 
 inline size_t sizeofPoolList(size_t n = ARDUINOJSON_INITIAL_POOL_COUNT) {
-  return sizeof(ArduinoJson::detail::VariantPool) * n;
+  using namespace ArduinoJson::detail;
+  return sizeof(MemoryPool<VariantData>) * n;
 }
 
+template <typename T = ArduinoJson::detail::VariantData>
 inline size_t sizeofPool(
     ArduinoJson::detail::SlotCount n = ARDUINOJSON_POOL_CAPACITY) {
-  return ArduinoJson::detail::VariantPool::slotsToBytes(n);
+  return ArduinoJson::detail::MemoryPool<T>::slotsToBytes(n);
 }
 
 inline size_t sizeofStringBuffer(size_t iteration = 1) {

extras/tests/Helpers/Arduino.h

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once

extras/tests/Helpers/CustomReader.hpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once

extras/tests/Helpers/Literals.hpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once

extras/tests/Helpers/api/Print.h

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once
@@ -13,21 +13,21 @@ class Print {
   virtual ~Print() {}
 
   virtual size_t write(uint8_t) = 0;
-  virtual size_t write(const uint8_t *buffer, size_t size) = 0;
+  virtual size_t write(const uint8_t* buffer, size_t size) = 0;
 
-  size_t write(const char *str) {
+  size_t write(const char* str) {
     if (!str)
       return 0;
-    return write(reinterpret_cast<const uint8_t *>(str), strlen(str));
+    return write(reinterpret_cast<const uint8_t*>(str), strlen(str));
   }
 
-  size_t write(const char *buffer, size_t size) {
-    return write(reinterpret_cast<const uint8_t *>(buffer), size);
+  size_t write(const char* buffer, size_t size) {
+    return write(reinterpret_cast<const uint8_t*>(buffer), size);
   }
 };
 
 class Printable {
  public:
   virtual ~Printable() {}
-  virtual size_t printTo(Print &p) const = 0;
+  virtual size_t printTo(Print& p) const = 0;
 };

extras/tests/Helpers/api/Stream.h

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once
@@ -10,5 +10,5 @@ class Stream  // : public Print
  public:
   virtual ~Stream() {}
   virtual int read() = 0;
-  virtual size_t readBytes(char *buffer, size_t length) = 0;
+  virtual size_t readBytes(char* buffer, size_t length) = 0;
 };

extras/tests/Helpers/api/String.h

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once

extras/tests/Helpers/avr/pgmspace.h

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #pragma once

extras/tests/IntegrationTests/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 add_executable(IntegrationTests

extras/tests/IntegrationTests/gbathree.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/IntegrationTests/issue772.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/IntegrationTests/openweathermap.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/IntegrationTests/round_trip.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 add_executable(JsonArrayTests
@@ -13,7 +13,6 @@ add_executable(JsonArrayTests
 	nesting.cpp
 	remove.cpp
 	size.cpp
-	std_string.cpp
 	subscript.cpp
 	unbound.cpp
 )

extras/tests/JsonArray/add.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>
@@ -8,7 +8,7 @@
 #include "Allocators.hpp"
 #include "Literals.hpp"
 
-using ArduinoJson::detail::sizeofArray;
+using namespace ArduinoJson::detail;
 
 TEST_CASE("JsonArray::add(T)") {
   SpyingAllocator spy;
@@ -17,31 +17,114 @@ TEST_CASE("JsonArray::add(T)") {
 
   SECTION("int") {
     array.add(123);
+
     REQUIRE(123 == array[0].as<int>());
     REQUIRE(array[0].is<int>());
     REQUIRE(array[0].is<double>());
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                         });
   }
 
   SECTION("double") {
     array.add(123.45);
+
     REQUIRE(123.45 == array[0].as<double>());
     REQUIRE(array[0].is<double>());
     REQUIRE_FALSE(array[0].is<bool>());
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool<VariantData>()),
+                             Allocate(sizeofPool<EightByteValue>()),
+                         });
   }
 
   SECTION("bool") {
     array.add(true);
-    REQUIRE(true == array[0].as<bool>());
+
+    REQUIRE(array[0].as<bool>() == true);
     REQUIRE(array[0].is<bool>());
     REQUIRE_FALSE(array[0].is<int>());
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                         });
+  }
+
+  SECTION("string literal") {
+    array.add("hello");
+
+    REQUIRE(array[0].as<std::string>() == "hello");
+    REQUIRE(array[0].is<const char*>());
+    REQUIRE(array[0].is<int>() == false);
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("hello")),
+                         });
+  }
+
+  SECTION("std::string") {
+    array.add("hello"_s);
+
+    REQUIRE(array[0].as<std::string>() == "hello");
+    REQUIRE(array[0].is<const char*>() == true);
+    REQUIRE(array[0].is<int>() == false);
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("hello")),
+                         });
   }
 
   SECTION("const char*") {
     const char* str = "hello";
     array.add(str);
-    REQUIRE(str == array[0].as<std::string>());
-    REQUIRE(array[0].is<const char*>());
-    REQUIRE_FALSE(array[0].is<int>());
+
+    REQUIRE(array[0].as<std::string>() == "hello");
+    REQUIRE(array[0].as<const char*>() != str);
+    REQUIRE(array[0].is<const char*>() == true);
+    REQUIRE(array[0].is<int>() == false);
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("hello")),
+                         });
+  }
+
+  SECTION("serialized(const char*)") {
+    array.add(serialized("{}"));
+
+    REQUIRE(doc.as<std::string>() == "[{}]");
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("{}")),
+                         });
+  }
+
+  SECTION("serialized(char*)") {
+    array.add(serialized(const_cast<char*>("{}")));
+
+    REQUIRE(doc.as<std::string>() == "[{}]");
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("{}")),
+                         });
+  }
+
+  SECTION("serialized(std::string)") {
+    array.add(serialized("{}"_s));
+
+    REQUIRE(doc.as<std::string>() == "[{}]");
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("{}")),
+                         });
+  }
+
+  SECTION("serialized(std::string)") {
+    array.add(serialized("\0XX"_s));
+
+    REQUIRE(doc.as<std::string>() == "[\0XX]"_s);
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString(" XX")),
+                         });
   }
 
 #ifdef HAS_VARIABLE_LENGTH_ARRAY
@@ -52,7 +135,12 @@ TEST_CASE("JsonArray::add(T)") {
 
     array.add(vla);
 
-    REQUIRE("world"_s == array[0]);
+    strcpy(vla, "hello");
+    REQUIRE(array[0] == "world"_s);
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("hello")),
+                         });
   }
 #endif
 
@@ -99,61 +187,6 @@ TEST_CASE("JsonArray::add(T)") {
 
     REQUIRE(str == array[0]);
   }
-
-  SECTION("should not duplicate const char*") {
-    array.add("world");
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                         });
-  }
-
-  SECTION("should duplicate char*") {
-    array.add(const_cast<char*>("world"));
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString("world")),
-                         });
-  }
-
-  SECTION("should duplicate std::string") {
-    array.add("world"_s);
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString("world")),
-                         });
-  }
-
-  SECTION("should duplicate serialized(const char*)") {
-    array.add(serialized("{}"));
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString("{}")),
-                         });
-  }
-
-  SECTION("should duplicate serialized(char*)") {
-    array.add(serialized(const_cast<char*>("{}")));
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString("{}")),
-                         });
-  }
-
-  SECTION("should duplicate serialized(std::string)") {
-    array.add(serialized("{}"_s));
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString("{}")),
-                         });
-  }
-
-  SECTION("should duplicate serialized(std::string)") {
-    array.add(serialized("\0XX"_s));
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString(" XX")),
-                         });
-  }
 }
 
 TEST_CASE("JsonArray::add<T>()") {

extras/tests/JsonArray/clear.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/compare.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/copyArray.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/equals.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/isNull.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/iterator.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/nesting.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/remove.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>
@@ -68,6 +68,12 @@ TEST_CASE("JsonArray::remove()") {
     REQUIRE(array[1] == 2);
   }
 
+  SECTION("remove end()") {
+    array.remove(array.end());
+
+    REQUIRE(3 == array.size());
+  }
+
   SECTION("In a loop") {
     for (JsonArray::iterator it = array.begin(); it != array.end(); ++it) {
       if (*it == 2)

extras/tests/JsonArray/size.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArray/std_string.cpp

@@ -1,34 +0,0 @@
-// ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
-// MIT License
-
-#include <ArduinoJson.h>
-#include <catch.hpp>
-
-#include "Literals.hpp"
-
-static void eraseString(std::string& str) {
-  char* p = const_cast<char*>(str.c_str());
-  while (*p)
-    *p++ = '*';
-}
-
-TEST_CASE("std::string") {
-  JsonDocument doc;
-  JsonArray array = doc.to<JsonArray>();
-
-  SECTION("add()") {
-    std::string value("hello");
-    array.add(value);
-    eraseString(value);
-    REQUIRE("hello"_s == array[0]);
-  }
-
-  SECTION("operator[]") {
-    std::string value("world");
-    array.add("hello");
-    array[0] = value;
-    eraseString(value);
-    REQUIRE("world"_s == array[0]);
-  }
-}

extras/tests/JsonArray/subscript.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>
@@ -59,15 +59,56 @@ TEST_CASE("JsonArray::operator[]") {
     REQUIRE(false == array[0].is<int>());
   }
 
-  SECTION("const char*") {
-    const char* str = "hello";
+  SECTION("string literal") {
+    array[0] = "hello";
 
-    array[0] = str;
-    REQUIRE(str == array[0].as<const char*>());
+    REQUIRE(array[0].as<std::string>() == "hello");
     REQUIRE(true == array[0].is<const char*>());
     REQUIRE(false == array[0].is<int>());
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("world")),
+                         });
   }
 
+  SECTION("const char*") {
+    const char* str = "hello";
+    array[0] = str;
+
+    REQUIRE(array[0].as<std::string>() == "hello");
+    REQUIRE(true == array[0].is<const char*>());
+    REQUIRE(false == array[0].is<int>());
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("world")),
+                         });
+  }
+
+  SECTION("std::string") {
+    array[0] = "hello"_s;
+
+    REQUIRE(array[0].as<std::string>() == "hello");
+    REQUIRE(true == array[0].is<const char*>());
+    REQUIRE(false == array[0].is<int>());
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofPool()),
+                             Allocate(sizeofString("world")),
+                         });
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("VLA") {
+    size_t i = 16;
+    char vla[i];
+    strcpy(vla, "world");
+
+    array.add("hello");
+    array[0] = vla;
+
+    REQUIRE(array[0] == "world"_s);
+  }
+#endif
+
   SECTION("nested array") {
     JsonDocument doc2;
     JsonArray arr2 = doc2.to<JsonArray>();
@@ -114,58 +155,11 @@ TEST_CASE("JsonArray::operator[]") {
     REQUIRE(str == array[0]);
   }
 
-  SECTION("should not duplicate const char*") {
-    array[0] = "world";
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                         });
-  }
-
-  SECTION("should duplicate char*") {
-    array[0] = const_cast<char*>("world");
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString("world")),
-                         });
-  }
-
-  SECTION("should duplicate std::string") {
-    array[0] = "world"_s;
-    REQUIRE(spy.log() == AllocatorLog{
-                             Allocate(sizeofPool()),
-                             Allocate(sizeofString("world")),
-                         });
-  }
-
   SECTION("array[0].to<JsonObject>()") {
     JsonObject obj = array[0].to<JsonObject>();
     REQUIRE(obj.isNull() == false);
   }
 
-#ifdef HAS_VARIABLE_LENGTH_ARRAY
-  SECTION("set(VLA)") {
-    size_t i = 16;
-    char vla[i];
-    strcpy(vla, "world");
-
-    array.add("hello");
-    array[0].set(vla);
-
-    REQUIRE("world"_s == array[0]);
-  }
-
-  SECTION("operator=(VLA)") {
-    size_t i = 16;
-    char vla[i];
-    strcpy(vla, "world");
-
-    array.add("hello");
-    array[0] = vla;
-
-    REQUIRE("world"_s == array[0]);
-  }
-#endif
-
   SECTION("Use a JsonVariant as index") {
     array[0] = 1;
     array[1] = 2;

extras/tests/JsonArray/unbound.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArrayConst/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 add_executable(JsonArrayConstTests

extras/tests/JsonArrayConst/equals.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArrayConst/isNull.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArrayConst/iterator.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArrayConst/nesting.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArrayConst/size.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonArrayConst/subscript.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonDeserializer/CMakeLists.txt

@@ -1,5 +1,5 @@
 # ArduinoJson - https://arduinojson.org
-# Copyright © 2014-2024, Benoit BLANCHON
+# Copyright © 2014-2025, Benoit BLANCHON
 # MIT License
 
 add_executable(JsonDeserializerTests

extras/tests/JsonDeserializer/DeserializationError.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonDeserializer/array.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>
@@ -7,7 +7,7 @@
 
 #include "Allocators.hpp"
 
-using ArduinoJson::detail::sizeofArray;
+using namespace ArduinoJson::detail;
 
 TEST_CASE("deserialize JSON array") {
   SpyingAllocator spy;
@@ -69,14 +69,36 @@ TEST_CASE("deserialize JSON array") {
       REQUIRE(arr[1] == 84);
     }
 
-    SECTION("Double") {
+    SECTION("Float") {
       DeserializationError err = deserializeJson(doc, "[4.2,1e2]");
       JsonArray arr = doc.as<JsonArray>();
 
       REQUIRE(err == DeserializationError::Ok);
       REQUIRE(2 == arr.size());
-      REQUIRE(arr[0] == 4.2);
-      REQUIRE(arr[1] == 1e2);
+      REQUIRE(arr[0].as<float>() == Approx(4.2f));
+      REQUIRE(arr[1] == 1e2f);
+      REQUIRE(spy.log() == AllocatorLog{
+                               Allocate(sizeofPool()),
+                               Reallocate(sizeofPool(), sizeofPool(2)),
+                           });
+    }
+
+    SECTION("Double") {
+      DeserializationError err = deserializeJson(doc, "[4.2123456,-7E89]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0].as<double>() == Approx(4.2123456));
+      REQUIRE(arr[1] == -7E89);
+      REQUIRE(spy.log() == AllocatorLog{
+                               Allocate(sizeofPool<VariantData>()),
+                               Allocate(sizeofPool<EightByteValue>()),
+                               Reallocate(sizeofPool<VariantData>(),
+                                          sizeofPool<VariantData>(2)),
+                               Reallocate(sizeofPool<EightByteValue>(),
+                                          sizeofPool<EightByteValue>(2)),
+                           });
     }
 
     SECTION("Unsigned long") {

extras/tests/JsonDeserializer/destination_types.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>
@@ -104,6 +104,8 @@ TEST_CASE("deserializeJson(MemberProxy)") {
 
     REQUIRE(err == DeserializationError::Ok);
     REQUIRE(doc.as<std::string>() == "{\"hello\":\"world\",\"value\":[42]}");
-    REQUIRE(spy.log() == AllocatorLog{});
+    REQUIRE(spy.log() == AllocatorLog{
+                             Allocate(sizeofString("value")),
+                         });
   }
 }

extras/tests/JsonDeserializer/errors.cpp

@@ -1,11 +1,13 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #define ARDUINOJSON_DECODE_UNICODE 1
 #include <ArduinoJson.h>
 #include <catch.hpp>
 
+#include "Allocators.hpp"
+
 TEST_CASE("deserializeJson() returns IncompleteInput") {
   const char* testCases[] = {
       // strings
@@ -118,3 +120,43 @@ TEST_CASE("deserializeJson() returns NoMemory if string length overflows") {
     REQUIRE(err == DeserializationError::NoMemory);
   }
 }
+
+TEST_CASE("deserializeJson() returns NoMemory if 8-bit slot allocation fails") {
+  JsonDocument doc(FailingAllocator::instance());
+
+  SECTION("uint32_t should pass") {
+    auto err = deserializeJson(doc, "4294967295");
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("uint64_t should fail") {
+    auto err = deserializeJson(doc, "18446744073709551615");
+
+    REQUIRE(err == DeserializationError::NoMemory);
+  }
+
+  SECTION("int32_t should pass") {
+    auto err = deserializeJson(doc, "-2147483648");
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("int64_t should fail") {
+    auto err = deserializeJson(doc, "-9223372036854775808");
+
+    REQUIRE(err == DeserializationError::NoMemory);
+  }
+
+  SECTION("float should pass") {
+    auto err = deserializeJson(doc, "3.402823e38");
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("double should fail") {
+    auto err = deserializeJson(doc, "1.7976931348623157e308");
+
+    REQUIRE(err == DeserializationError::NoMemory);
+  }
+}

extras/tests/JsonDeserializer/filter.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #define ARDUINOJSON_ENABLE_COMMENTS 1
@@ -693,6 +693,15 @@ TEST_CASE("Filtering") {
           "null",
           0,
       },
+      {
+          "NUL character in key",
+          "{\"x\":0,\"x\\u0000a\":1,\"x\\u0000b\":2}",
+          "{\"x\\u0000a\":true}",
+          10,
+          DeserializationError::Ok,
+          "{\"x\\u0000a\":1}",
+          sizeofObject(1) + sizeofString("x?a"),
+      },
   };
 
   for (auto& tc : testCases) {

extras/tests/JsonDeserializer/input_types.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>
@@ -26,8 +26,8 @@ TEST_CASE("deserializeJson(char*)") {
   REQUIRE(spy.log() ==
           AllocatorLog{
               Allocate(sizeofStringBuffer()),
-              Reallocate(sizeofStringBuffer(), sizeofString("hello")),
               Allocate(sizeofPool()),
+              Reallocate(sizeofStringBuffer(), sizeofString("hello")),
               Allocate(sizeofStringBuffer()),
               Reallocate(sizeofStringBuffer(), sizeofString("world")),
               Reallocate(sizeofPool(), sizeofObject(1)),

extras/tests/JsonDeserializer/misc.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonDeserializer/nestingLimit.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #include <ArduinoJson.h>

extras/tests/JsonDeserializer/number.cpp

@@ -1,5 +1,5 @@
 // ArduinoJson - https://arduinojson.org
-// Copyright © 2014-2024, Benoit BLANCHON
+// Copyright © 2014-2025, Benoit BLANCHON
 // MIT License
 
 #define ARDUINOJSON_USE_LONG_LONG 0