Set version to 5.11.2

.travis.yml

@@ -8,12 +8,6 @@ matrix:
           sources: ['ubuntu-toolchain-r-test']
           packages: ['g++-4.4']
       env: SCRIPT=cmake GCC=4.4
-    - compiler: gcc
-      addons:
-        apt:
-          sources: ['ubuntu-toolchain-r-test']
-          packages: ['g++-4.5']
-      env: SCRIPT=cmake GCC=4.5
     - compiler: gcc
       addons:
         apt:
@@ -50,6 +44,12 @@ matrix:
           sources: ['ubuntu-toolchain-r-test']
           packages: ['g++-6']
       env: SCRIPT=cmake GCC=6
+    - compiler: gcc
+      addons:
+        apt:
+          sources: ['ubuntu-toolchain-r-test']
+          packages: ['g++-7']
+      env: SCRIPT=cmake GCC=7
     - compiler: clang
       env: SCRIPT=cmake
     - compiler: clang
@@ -89,9 +89,7 @@ matrix:
     - env: SCRIPT=arduino VERSION=1.6.7 BOARD=arduino:avr:uno
     - env: SCRIPT=arduino VERSION=1.8.2 BOARD=arduino:avr:uno
     - env: SCRIPT=platformio BOARD=uno
-    - env: SCRIPT=platformio BOARD=due
     - env: SCRIPT=platformio BOARD=esp01
-    #- env: SCRIPT=platformio BOARD=teensy31C
 cache:
   directories:
     - "~/.platformio"

CHANGELOG.md

@@ -1,6 +1,22 @@
 ArduinoJson: change log
 =======================
 
+v5.11.2
+-------
+
+* Fixed `DynamicJsonBuffer::clear()` not resetting allocation size (issue #561)
+* Fixed incorrect rounding for float values (issue #588)
+
+v5.11.1
+-------
+
+* Removed dependency on `PGM_P` as Particle 0.6.2 doesn't define it (issue #546)
+* Fixed warning "dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]"
+* Fixed warning "floating constant exceeds range of 'float' [-Woverflow]" (issue #544)
+* Fixed warning "this statement may fall through" [-Wimplicit-fallthrough=] (issue #539)
+* Removed `ARDUINOJSON_DOUBLE_IS_64BITS` as it became useless.
+* Fixed too many decimals places in float serialization (issue #543)
+
 v5.11.0
 -------
 

CONTRIBUTING.md

@@ -0,0 +1,11 @@
+# Contribution to ArduinoJson
+
+First, thank you for taking the time to contribute to this project.
+
+You can submit changes via GitHub Pull Requests.
+
+Please:
+
+1. Unit test every change in behavior
+2. Use clang-format in "file" mode to format the code
+3. Consider using the Continuous Integration (Travis and AppVeyor)

README.md

@@ -1,8 +1,10 @@
+[![Build status](https://ci.appveyor.com/api/projects/status/m7s53wav1l0abssg/branch/master?svg=true)](https://ci.appveyor.com/project/bblanchon/arduinojson/branch/master) [![Build Status](https://travis-ci.org/bblanchon/ArduinoJson.svg?branch=master)](https://travis-ci.org/bblanchon/ArduinoJson) [![Coverage Status](https://img.shields.io/coveralls/bblanchon/ArduinoJson.svg)](https://coveralls.io/r/bblanchon/ArduinoJson?branch=master) [![Star this project](http://githubbadges.com/star.svg?user=bblanchon&repo=ArduinoJson&style=flat&color=fff&background=007ec6)](https://github.com/bblanchon/ArduinoJson)
+
+![ArduinoJson's logo](banner.svg)
+
 ArduinoJson - C++ JSON library for IoT
 ====================
 
-[![Build status](https://ci.appveyor.com/api/projects/status/m7s53wav1l0abssg/branch/master?svg=true)](https://ci.appveyor.com/project/bblanchon/arduinojson/branch/master) [![Build Status](https://travis-ci.org/bblanchon/ArduinoJson.svg?branch=master)](https://travis-ci.org/bblanchon/ArduinoJson) [![Coverage Status](https://img.shields.io/coveralls/bblanchon/ArduinoJson.svg)](https://coveralls.io/r/bblanchon/ArduinoJson?branch=master) [![Star this project](http://githubbadges.com/star.svg?user=bblanchon&repo=ArduinoJson&style=flat&color=fff&background=007ec6)](https://github.com/bblanchon/ArduinoJson)
-
 *An elegant and efficient JSON library for embedded systems.*
 
 It's designed to have the most intuitive API, the smallest footprint and is able to work without any allocation on the heap (no malloc).
@@ -118,6 +120,9 @@ Special thanks to the following persons and companies who made generous donation
 * Prokhoryatov Alexey <img alt='Russia' src='https://cdnjs.cloudflare.com/ajax/libs/emojione/2.1.4/assets/svg/1f1f7-1f1fa.svg' width='18' height='18'>
 * Google Inc. <img alt='USA' src='https://cdnjs.cloudflare.com/ajax/libs/emojione/2.1.4/assets/svg/1f1fa-1f1f8.svg' width='18' height='18'>
 * Charles Haynes <img alt='Australia' src='https://d1j8pt39hxlh3d.cloudfront.net/development/emojione/2.2/989/2546.svg' width='18' height='18'>
+* Charles Walker <img alt='USA' src='https://cdnjs.cloudflare.com/ajax/libs/emojione/2.1.4/assets/svg/1f1fa-1f1f8.svg' width='18' height='18'>
+* Günther Jehle <img alt='Liechtenstein' src='https://cdnjs.cloudflare.com/ajax/libs/emojione/2.1.4/assets/svg/1f1f1-1f1ee.svg' width='18' height='18'>
+* Patrick Elliott
 
 
 ---

SUPPORT.md

@@ -0,0 +1,27 @@
+# ArduinoJson Support
+
+First off, thank you very much for using ArduinoJson.
+
+We'll be very happy to help you, but first please read the following.
+
+## Before asking for help
+
+1. Read the [FAQ](https://bblanchon.github.io/ArduinoJson/faq/)
+2. Search in the [API Reference](https://bblanchon.github.io/ArduinoJson/api/)
+
+If you did not find the answer, please create a [new issue on GitHub](https://github.com/bblanchon/ArduinoJson/issues/new).
+
+It is OK to add a comment to a currently opened issue, but please avoid adding comments to a closed issue.
+
+## Before hitting the Submit button
+
+Please provide all the relevant information:
+
+* Good title
+* Short description of the problem
+* Target platform
+* Compiler model and version
+* [MVCE](https://stackoverflow.com/help/mcve)
+* Compiler output
+
+Good questions get fast answers!

appveyor.yml

@@ -1,4 +1,4 @@
-version: 5.11.0.{build}
+version: 5.11.2.{build}
 environment:
   matrix:
   - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017

library.json

@@ -6,7 +6,7 @@
     "type": "git",
     "url": "https://github.com/bblanchon/ArduinoJson.git"
   },
-  "version": "5.11.0",
+  "version": "5.11.2",
   "authors": {
     "name": "Benoit Blanchon",
     "url": "https://blog.benoitblanchon.fr"

library.properties

@@ -1,5 +1,5 @@
 name=ArduinoJson
-version=5.11.0
+version=5.11.2
 author=Benoit Blanchon <blog.benoitblanchon.fr>
 maintainer=Benoit Blanchon <blog.benoitblanchon.fr>
 sentence=An efficient and elegant JSON library for Arduino.

src/ArduinoJson.hpp

@@ -10,7 +10,6 @@
 #include "ArduinoJson/DynamicJsonBuffer.hpp"
 #include "ArduinoJson/JsonArray.hpp"
 #include "ArduinoJson/JsonObject.hpp"
-#include "ArduinoJson/JsonVariantComparisons.hpp"
 #include "ArduinoJson/StaticJsonBuffer.hpp"
 
 #include "ArduinoJson/Deserialization/JsonParserImpl.hpp"

src/ArduinoJson/Configuration.hpp

@@ -148,16 +148,6 @@
 #define ARDUINOJSON_NEGATIVE_EXPONENTIATION_THRESHOLD 1e-5
 #endif
 
-// how many bits in a double
-#ifndef ARDUINOJSON_DOUBLE_IS_64BITS
-#if /*GCC*/ (defined(__SIZEOF_DOUBLE__) && __SIZEOF_DOUBLE__ < 8) || \
-    /*IAR*/ (defined(__DOUBLE__) && __DOUBLE__ < 64)
-#define ARDUINOJSON_DOUBLE_IS_64BITS 0
-#else
-#define ARDUINOJSON_DOUBLE_IS_64BITS 1  // by default support 64-bit
-#endif
-#endif
-
 #if ARDUINOJSON_USE_LONG_LONG && ARDUINOJSON_USE_INT64
 #error ARDUINOJSON_USE_LONG_LONG and ARDUINOJSON_USE_INT64 cannot be set together
 #endif

src/ArduinoJson/Data/JsonVariantComparer.hpp

@@ -1,69 +0,0 @@
-// Copyright Benoit Blanchon 2014-2017
-// MIT License
-//
-// Arduino JSON library
-// https://bblanchon.github.io/ArduinoJson/
-// If you like this project, please add a star!
-
-#pragma once
-
-#include "../JsonVariantBase.hpp"
-#include "../StringTraits/StringTraits.hpp"
-#include "../TypeTraits/EnableIf.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-template <typename TComparand, typename Enable = void>
-struct JsonVariantComparer {};
-
-template <typename TString>
-struct JsonVariantComparer<
-    TString,
-    typename TypeTraits::EnableIf<TypeTraits::IsString<TString>::value>::type> {
-  template <typename TVariant>
-  static bool equals(const JsonVariantBase<TVariant> &variant,
-                     const TString &comparand) {
-    const char *value = variant.template as<const char *>();
-    return Internals::StringTraits<TString>::equals(comparand, value);
-  }
-};
-
-template <typename TComparand>
-struct JsonVariantComparer<
-    TComparand, typename TypeTraits::EnableIf<
-                    !TypeTraits::IsVariant<TComparand>::value &&
-                    !TypeTraits::IsString<TComparand>::value>::type> {
-  template <typename TVariant>
-  static bool equals(const JsonVariantBase<TVariant> &variant,
-                     const TComparand &comparand) {
-    return variant.template as<TComparand>() == comparand;
-  }
-};
-
-template <typename TVariant2>
-struct JsonVariantComparer<TVariant2,
-                           typename TypeTraits::EnableIf<
-                               TypeTraits::IsVariant<TVariant2>::value>::type> {
-  template <typename TVariant1>
-  static bool equals(const JsonVariantBase<TVariant1> &left,
-                     const TVariant2 &right) {
-    if (left.template is<bool>() && right.template is<bool>())
-      return left.template as<bool>() == right.template as<bool>();
-    if (left.template is<JsonInteger>() && right.template is<JsonInteger>())
-      return left.template as<JsonInteger>() ==
-             right.template as<JsonInteger>();
-    if (left.template is<JsonFloat>() && right.template is<JsonFloat>())
-      return left.template as<JsonFloat>() == right.template as<JsonFloat>();
-    if (left.template is<JsonArray>() && right.template is<JsonArray>())
-      return left.template as<JsonArray>() == right.template as<JsonArray>();
-    if (left.template is<JsonObject>() && right.template is<JsonObject>())
-      return left.template as<JsonObject>() == right.template as<JsonObject>();
-    if (left.template is<char *>() && right.template is<char *>())
-      return strcmp(left.template as<char *>(), right.template as<char *>()) ==
-             0;
-
-    return false;
-  }
-};
-}
-}

src/ArduinoJson/DynamicJsonBuffer.hpp

@@ -52,7 +52,7 @@ class DynamicJsonBufferBase
       : _head(NULL), _nextBlockCapacity(initialSize) {}
 
   ~DynamicJsonBufferBase() {
-    freeAllBlocks();
+    clear();
   }
 
   // Gets the number of bytes occupied in the buffer
@@ -71,7 +71,13 @@ class DynamicJsonBufferBase
   // Resets the buffer.
   // USE WITH CAUTION: this invalidates all previously allocated data
   void clear() {
-    freeAllBlocks();
+    Block* currentBlock = _head;
+    while (currentBlock != NULL) {
+      _nextBlockCapacity = currentBlock->capacity;
+      Block* nextBlock = currentBlock->next;
+      _allocator.deallocate(currentBlock);
+      currentBlock = nextBlock;
+    }
     _head = 0;
   }
 
@@ -144,16 +150,6 @@ class DynamicJsonBufferBase
     return true;
   }
 
-  void freeAllBlocks() {
-    Block* currentBlock = _head;
-
-    while (currentBlock != NULL) {
-      Block* nextBlock = currentBlock->next;
-      _allocator.deallocate(currentBlock);
-      currentBlock = nextBlock;
-    }
-  }
-
   TAllocator _allocator;
   Block* _head;
   size_t _nextBlockCapacity;

src/ArduinoJson/JsonArraySubscript.hpp

@@ -106,15 +106,16 @@ inline const JsonArraySubscript JsonArray::operator[](size_t index) const {
   return JsonArraySubscript(*const_cast<JsonArray*>(this), index);
 }
 
-template <typename TImplem>
-inline JsonArraySubscript JsonVariantBase<TImplem>::operator[](size_t index) {
-  return as<JsonArray>()[index];
+template <typename TImpl>
+inline JsonArraySubscript JsonVariantSubscripts<TImpl>::operator[](
+    size_t index) {
+  return impl()->template as<JsonArray>()[index];
 }
 
-template <typename TImplem>
-inline const JsonArraySubscript JsonVariantBase<TImplem>::operator[](
+template <typename TImpl>
+inline const JsonArraySubscript JsonVariantSubscripts<TImpl>::operator[](
     size_t index) const {
-  return as<JsonArray>()[index];
+  return impl()->template as<JsonArray>()[index];
 }
 
 }  // namespace ArduinoJson

src/ArduinoJson/JsonBuffer.hpp

@@ -16,16 +16,6 @@
 #include "TypeTraits/EnableIf.hpp"
 #include "TypeTraits/IsArray.hpp"
 
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic push
-#endif
-#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-#endif
-
 namespace ArduinoJson {
 class JsonArray;
 class JsonObject;
@@ -37,11 +27,6 @@ class JsonObject;
 // fixed memory allocation.
 class JsonBuffer : Internals::NonCopyable {
  public:
-  // CAUTION: NO VIRTUAL DESTRUCTOR!
-  // If we add a virtual constructor the Arduino compiler will add malloc() and
-  // free() to the binary, adding 706 useless bytes.
-  // virtual ~JsonBuffer() {}
-
   // Allocates an empty JsonArray.
   //
   // Returns a reference to the new JsonArray or JsonArray::invalid() if the
@@ -77,6 +62,11 @@ class JsonBuffer : Internals::NonCopyable {
   virtual void *alloc(size_t size) = 0;
 
  protected:
+  // CAUTION: NO VIRTUAL DESTRUCTOR!
+  // If we add a virtual constructor the Arduino compiler will add malloc()
+  // and free() to the binary, adding 706 useless bytes.
+  ~JsonBuffer() {}
+
   // Preserve aligment if necessary
   static FORCE_INLINE size_t round_size_up(size_t bytes) {
 #if ARDUINOJSON_ENABLE_ALIGNMENT
@@ -88,11 +78,3 @@ class JsonBuffer : Internals::NonCopyable {
   }
 };
 }
-
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic pop
-#endif
-#endif

src/ArduinoJson/JsonBufferBase.hpp

@@ -9,16 +9,6 @@
 
 #include "Deserialization/JsonParser.hpp"
 
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic push
-#endif
-#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-#endif
-
 namespace ArduinoJson {
 template <typename TDerived>
 class JsonBufferBase : public JsonBuffer {
@@ -127,17 +117,12 @@ class JsonBufferBase : public JsonBuffer {
     return Internals::makeParser(that(), json, nestingLimit).parseVariant();
   }
 
+ protected:
+  ~JsonBufferBase() {}
+
  private:
   TDerived *that() {
     return static_cast<TDerived *>(this);
   }
 };
 }
-
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic pop
-#endif
-#endif

src/ArduinoJson/JsonVariantBase.hpp

@@ -7,133 +7,17 @@
 
 #pragma once
 
-#include "Data/JsonVariantAs.hpp"
-#include "Polyfills/attributes.hpp"
+#include "JsonVariantCasts.hpp"
+#include "JsonVariantComparisons.hpp"
+#include "JsonVariantSubscripts.hpp"
 #include "Serialization/JsonPrintable.hpp"
 
 namespace ArduinoJson {
 
-// Forward declarations.
-class JsonArraySubscript;
-template <typename TKey>
-class JsonObjectSubscript;
-
 template <typename TImpl>
-class JsonVariantBase : public Internals::JsonPrintable<TImpl> {
- public:
-#if ARDUINOJSON_ENABLE_DEPRECATED
-  DEPRECATED("use as<JsonArray>() instead")
-  FORCE_INLINE JsonArray &asArray() const {
-    return as<JsonArray>();
-  }
-
-  DEPRECATED("use as<JsonObject>() instead")
-  FORCE_INLINE JsonObject &asObject() const {
-    return as<JsonObject>();
-  }
-
-  DEPRECATED("use as<char*>() instead")
-  FORCE_INLINE const char *asString() const {
-    return as<const char *>();
-  }
-#endif
-
-  // Gets the variant as an array.
-  // Returns a reference to the JsonArray or JsonArray::invalid() if the
-  // variant
-  // is not an array.
-  FORCE_INLINE operator JsonArray &() const {
-    return as<JsonArray &>();
-  }
-
-  // Gets the variant as an object.
-  // Returns a reference to the JsonObject or JsonObject::invalid() if the
-  // variant is not an object.
-  FORCE_INLINE operator JsonObject &() const {
-    return as<JsonObject &>();
-  }
-
-  template <typename T>
-  FORCE_INLINE operator T() const {
-    return as<T>();
-  }
-
-  template <typename T>
-  FORCE_INLINE const typename Internals::JsonVariantAs<T>::type as() const {
-    return impl()->template as<T>();
-  }
-
-  template <typename T>
-  FORCE_INLINE bool is() const {
-    return impl()->template is<T>();
-  }
-
-  // Mimics an array or an object.
-  // Returns the size of the array or object if the variant has that type.
-  // Returns 0 if the variant is neither an array nor an object
-  size_t size() const {
-    return as<JsonArray>().size() + as<JsonObject>().size();
-  }
-
-  // Mimics an array.
-  // Returns the element at specified index if the variant is an array.
-  // Returns JsonVariant::invalid() if the variant is not an array.
-  FORCE_INLINE const JsonArraySubscript operator[](size_t index) const;
-  FORCE_INLINE JsonArraySubscript operator[](size_t index);
-
-  // Mimics an object.
-  // Returns the value associated with the specified key if the variant is
-  // an object.
-  // Return JsonVariant::invalid() if the variant is not an object.
-  //
-  // const JsonObjectSubscript operator[](TKey) const;
-  // TKey = const std::string&, const String&
-  template <typename TString>
-  FORCE_INLINE typename TypeTraits::EnableIf<
-      Internals::StringTraits<TString>::has_equals,
-      const JsonObjectSubscript<const TString &> >::type
-  operator[](const TString &key) const {
-    return as<JsonObject>()[key];
-  }
-  //
-  // const JsonObjectSubscript operator[](TKey) const;
-  // TKey = const std::string&, const String&
-  template <typename TString>
-  FORCE_INLINE typename TypeTraits::EnableIf<
-      Internals::StringTraits<TString>::has_equals,
-      JsonObjectSubscript<const TString &> >::type
-  operator[](const TString &key) {
-    return as<JsonObject>()[key];
-  }
-  //
-  // JsonObjectSubscript operator[](TKey);
-  // TKey = const char*, const char[N], const FlashStringHelper*
-  template <typename TString>
-  FORCE_INLINE typename TypeTraits::EnableIf<
-      Internals::StringTraits<const TString *>::has_equals,
-      JsonObjectSubscript<const TString *> >::type
-  operator[](const TString *key) {
-    return as<JsonObject>()[key];
-  }
-  //
-  // JsonObjectSubscript operator[](TKey);
-  // TKey = const char*, const char[N], const FlashStringHelper*
-  template <typename TString>
-  FORCE_INLINE typename TypeTraits::EnableIf<
-      Internals::StringTraits<TString *>::has_equals,
-      const JsonObjectSubscript<const TString *> >::type
-  operator[](const TString *key) const {
-    return as<JsonObject>()[key];
-  }
-
- private:
-  const TImpl *impl() const {
-    return static_cast<const TImpl *>(this);
-  }
-};
-
-namespace TypeTraits {
-template <typename T>
-struct IsVariant : IsBaseOf<JsonVariantBase<T>, T> {};
-}
+class JsonVariantBase : public Internals::JsonPrintable<TImpl>,
+                        public JsonVariantCasts<TImpl>,
+                        public JsonVariantComparisons<TImpl>,
+                        public JsonVariantSubscripts<TImpl>,
+                        public TypeTraits::JsonVariantTag {};
 }

src/ArduinoJson/JsonVariantCasts.hpp

@@ -0,0 +1,60 @@
+// Copyright Benoit Blanchon 2014-2017
+// MIT License
+//
+// Arduino JSON library
+// https://bblanchon.github.io/ArduinoJson/
+// If you like this project, please add a star!
+
+#pragma once
+
+#include "Data/JsonVariantAs.hpp"
+#include "Polyfills/attributes.hpp"
+
+namespace ArduinoJson {
+
+template <typename TImpl>
+class JsonVariantCasts {
+ public:
+#if ARDUINOJSON_ENABLE_DEPRECATED
+  DEPRECATED("use as<JsonArray>() instead")
+  FORCE_INLINE JsonArray &asArray() const {
+    return impl()->template as<JsonArray>();
+  }
+
+  DEPRECATED("use as<JsonObject>() instead")
+  FORCE_INLINE JsonObject &asObject() const {
+    return impl()->template as<JsonObject>();
+  }
+
+  DEPRECATED("use as<char*>() instead")
+  FORCE_INLINE const char *asString() const {
+    return impl()->template as<const char *>();
+  }
+#endif
+
+  // Gets the variant as an array.
+  // Returns a reference to the JsonArray or JsonArray::invalid() if the
+  // variant
+  // is not an array.
+  FORCE_INLINE operator JsonArray &() const {
+    return impl()->template as<JsonArray &>();
+  }
+
+  // Gets the variant as an object.
+  // Returns a reference to the JsonObject or JsonObject::invalid() if the
+  // variant is not an object.
+  FORCE_INLINE operator JsonObject &() const {
+    return impl()->template as<JsonObject &>();
+  }
+
+  template <typename T>
+  FORCE_INLINE operator T() const {
+    return impl()->template as<T>();
+  }
+
+ private:
+  const TImpl *impl() const {
+    return static_cast<const TImpl *>(this);
+  }
+};
+}

src/ArduinoJson/JsonVariantComparisons.hpp

@@ -7,82 +7,138 @@
 
 #pragma once
 
-#include "Data/JsonVariantComparer.hpp"
+#include "StringTraits/StringTraits.hpp"
+#include "TypeTraits/EnableIf.hpp"
+#include "TypeTraits/IsVariant.hpp"
 
 namespace ArduinoJson {
-template <typename TVariant, typename TComparand>
-inline bool operator==(const JsonVariantBase<TVariant> &variant,
-                       TComparand comparand) {
-  return Internals::JsonVariantComparer<TComparand>::equals(variant, comparand);
-}
 
-template <typename TVariant, typename TComparand>
-inline typename TypeTraits::EnableIf<!TypeTraits::IsVariant<TComparand>::value,
-                                     bool>::type
-operator==(TComparand comparand, const JsonVariantBase<TVariant> &variant) {
-  return Internals::JsonVariantComparer<TComparand>::equals(variant, comparand);
-}
+template <typename TImpl>
+class JsonVariantComparisons {
+ public:
+  template <typename TComparand>
+  friend bool operator==(const JsonVariantComparisons &variant,
+                         TComparand comparand) {
+    return variant.equals(comparand);
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator!=(const JsonVariantBase<TVariant> &variant,
-                       TComparand comparand) {
-  return !Internals::JsonVariantComparer<TComparand>::equals(variant,
-                                                             comparand);
-}
+  template <typename TComparand>
+  friend
+      typename TypeTraits::EnableIf<!TypeTraits::IsVariant<TComparand>::value,
+                                    bool>::type
+      operator==(TComparand comparand, const JsonVariantComparisons &variant) {
+    return variant.equals(comparand);
+  }
 
-template <typename TVariant, typename TComparand>
-inline typename TypeTraits::EnableIf<!TypeTraits::IsVariant<TComparand>::value,
-                                     bool>::type
-operator!=(TComparand comparand, const JsonVariantBase<TVariant> &variant) {
-  return !Internals::JsonVariantComparer<TComparand>::equals(variant,
-                                                             comparand);
-}
+  template <typename TComparand>
+  friend bool operator!=(const JsonVariantComparisons &variant,
+                         TComparand comparand) {
+    return !variant.equals(comparand);
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator<=(const JsonVariantBase<TVariant> &left,
-                       TComparand right) {
-  return left.template as<TComparand>() <= right;
-}
+  template <typename TComparand>
+  friend
+      typename TypeTraits::EnableIf<!TypeTraits::IsVariant<TComparand>::value,
+                                    bool>::type
+      operator!=(TComparand comparand, const JsonVariantComparisons &variant) {
+    return !variant.equals(comparand);
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator<=(TComparand comparand,
-                       const JsonVariantBase<TVariant> &variant) {
-  return comparand <= variant.template as<TComparand>();
-}
+  template <typename TComparand>
+  friend bool operator<=(const JsonVariantComparisons &left, TComparand right) {
+    return left.as<TComparand>() <= right;
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator>=(const JsonVariantBase<TVariant> &variant,
-                       TComparand comparand) {
-  return variant.template as<TComparand>() >= comparand;
-}
+  template <typename TComparand>
+  friend bool operator<=(TComparand comparand,
+                         const JsonVariantComparisons &variant) {
+    return comparand <= variant.as<TComparand>();
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator>=(TComparand comparand,
-                       const JsonVariantBase<TVariant> &variant) {
-  return comparand >= variant.template as<TComparand>();
-}
+  template <typename TComparand>
+  friend bool operator>=(const JsonVariantComparisons &variant,
+                         TComparand comparand) {
+    return variant.as<TComparand>() >= comparand;
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator<(const JsonVariantBase<TVariant> &varian,
-                      TComparand comparand) {
-  return varian.template as<TComparand>() < comparand;
-}
+  template <typename TComparand>
+  friend bool operator>=(TComparand comparand,
+                         const JsonVariantComparisons &variant) {
+    return comparand >= variant.as<TComparand>();
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator<(TComparand comparand,
-                      const JsonVariantBase<TVariant> &variant) {
-  return comparand < variant.template as<TComparand>();
-}
+  template <typename TComparand>
+  friend bool operator<(const JsonVariantComparisons &varian,
+                        TComparand comparand) {
+    return varian.as<TComparand>() < comparand;
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator>(const JsonVariantBase<TVariant> &variant,
-                      TComparand comparand) {
-  return variant.template as<TComparand>() > comparand;
-}
+  template <typename TComparand>
+  friend bool operator<(TComparand comparand,
+                        const JsonVariantComparisons &variant) {
+    return comparand < variant.as<TComparand>();
+  }
 
-template <typename TVariant, typename TComparand>
-inline bool operator>(TComparand comparand,
-                      const JsonVariantBase<TVariant> &variant) {
-  return comparand > variant.template as<TComparand>();
-}
+  template <typename TComparand>
+  friend bool operator>(const JsonVariantComparisons &variant,
+                        TComparand comparand) {
+    return variant.as<TComparand>() > comparand;
+  }
+
+  template <typename TComparand>
+  friend bool operator>(TComparand comparand,
+                        const JsonVariantComparisons &variant) {
+    return comparand > variant.as<TComparand>();
+  }
+
+ private:
+  const TImpl *impl() const {
+    return static_cast<const TImpl *>(this);
+  }
+
+  template <typename T>
+  const typename Internals::JsonVariantAs<T>::type as() const {
+    return impl()->template as<T>();
+  }
+
+  template <typename T>
+  bool is() const {
+    return impl()->template is<T>();
+  }
+
+  template <typename TString>
+  typename TypeTraits::EnableIf<TypeTraits::IsString<TString>::value,
+                                bool>::type
+  equals(const TString &comparand) const {
+    const char *value = as<const char *>();
+    return Internals::StringTraits<TString>::equals(comparand, value);
+  }
+
+  template <typename TComparand>
+  typename TypeTraits::EnableIf<!TypeTraits::IsVariant<TComparand>::value &&
+                                    !TypeTraits::IsString<TComparand>::value,
+                                bool>::type
+  equals(const TComparand &comparand) const {
+    return as<TComparand>() == comparand;
+  }
+
+  template <typename TVariant2>
+  bool equals(const JsonVariantComparisons<TVariant2> &right) const {
+    using namespace Internals;
+    if (is<bool>() && right.template is<bool>())
+      return as<bool>() == right.template as<bool>();
+    if (is<JsonInteger>() && right.template is<JsonInteger>())
+      return as<JsonInteger>() == right.template as<JsonInteger>();
+    if (is<JsonFloat>() && right.template is<JsonFloat>())
+      return as<JsonFloat>() == right.template as<JsonFloat>();
+    if (is<JsonArray>() && right.template is<JsonArray>())
+      return as<JsonArray>() == right.template as<JsonArray>();
+    if (is<JsonObject>() && right.template is<JsonObject>())
+      return as<JsonObject>() == right.template as<JsonObject>();
+    if (is<char *>() && right.template is<char *>())
+      return strcmp(as<char *>(), right.template as<char *>()) == 0;
+
+    return false;
+  }
+};
 }

src/ArduinoJson/JsonVariantSubscripts.hpp

@@ -0,0 +1,89 @@
+// Copyright Benoit Blanchon 2014-2017
+// MIT License
+//
+// Arduino JSON library
+// https://bblanchon.github.io/ArduinoJson/
+// If you like this project, please add a star!
+
+#pragma once
+
+#include "Data/JsonVariantAs.hpp"
+#include "Polyfills/attributes.hpp"
+#include "StringTraits/StringTraits.hpp"
+#include "TypeTraits/EnableIf.hpp"
+
+namespace ArduinoJson {
+
+// Forward declarations.
+class JsonArraySubscript;
+template <typename TKey>
+class JsonObjectSubscript;
+
+template <typename TImpl>
+class JsonVariantSubscripts {
+ public:
+  // Mimics an array or an object.
+  // Returns the size of the array or object if the variant has that type.
+  // Returns 0 if the variant is neither an array nor an object
+  size_t size() const {
+    return impl()->template as<JsonArray>().size() +
+           impl()->template as<JsonObject>().size();
+  }
+
+  // Mimics an array.
+  // Returns the element at specified index if the variant is an array.
+  // Returns JsonVariant::invalid() if the variant is not an array.
+  FORCE_INLINE const JsonArraySubscript operator[](size_t index) const;
+  FORCE_INLINE JsonArraySubscript operator[](size_t index);
+
+  // Mimics an object.
+  // Returns the value associated with the specified key if the variant is
+  // an object.
+  // Return JsonVariant::invalid() if the variant is not an object.
+  //
+  // const JsonObjectSubscript operator[](TKey) const;
+  // TKey = const std::string&, const String&
+  template <typename TString>
+  FORCE_INLINE typename TypeTraits::EnableIf<
+      Internals::StringTraits<TString>::has_equals,
+      const JsonObjectSubscript<const TString &> >::type
+  operator[](const TString &key) const {
+    return impl()->template as<JsonObject>()[key];
+  }
+  //
+  // const JsonObjectSubscript operator[](TKey) const;
+  // TKey = const std::string&, const String&
+  template <typename TString>
+  FORCE_INLINE typename TypeTraits::EnableIf<
+      Internals::StringTraits<TString>::has_equals,
+      JsonObjectSubscript<const TString &> >::type
+  operator[](const TString &key) {
+    return impl()->template as<JsonObject>()[key];
+  }
+  //
+  // JsonObjectSubscript operator[](TKey);
+  // TKey = const char*, const char[N], const FlashStringHelper*
+  template <typename TString>
+  FORCE_INLINE typename TypeTraits::EnableIf<
+      Internals::StringTraits<const TString *>::has_equals,
+      JsonObjectSubscript<const TString *> >::type
+  operator[](const TString *key) {
+    return impl()->template as<JsonObject>()[key];
+  }
+  //
+  // JsonObjectSubscript operator[](TKey);
+  // TKey = const char*, const char[N], const FlashStringHelper*
+  template <typename TString>
+  FORCE_INLINE typename TypeTraits::EnableIf<
+      Internals::StringTraits<TString *>::has_equals,
+      const JsonObjectSubscript<const TString *> >::type
+  operator[](const TString *key) const {
+    return impl()->template as<JsonObject>()[key];
+  }
+
+ private:
+  const TImpl *impl() const {
+    return static_cast<const TImpl *>(this);
+  }
+};
+}

src/ArduinoJson/Polyfills/normalize.hpp

@@ -1,103 +0,0 @@
-// Copyright Benoit Blanchon 2014-2017
-// MIT License
-//
-// Arduino JSON library
-// https://bblanchon.github.io/ArduinoJson/
-// If you like this project, please add a star!
-
-#pragma once
-
-#include "../Configuration.hpp"
-
-namespace ArduinoJson {
-namespace Polyfills {
-template <typename T>
-int16_t normalize(T& value) {
-  int16_t powersOf10 = 0;
-
-  if (value >= ARDUINOJSON_POSITIVE_EXPONENTIATION_THRESHOLD) {
-#if ARDUINOJSON_DOUBLE_IS_64BITS
-    if (value >= 1e256) {
-      value /= 1e256;
-      powersOf10 = int16_t(powersOf10 + 256);
-    }
-    if (value >= 1e128) {
-      value /= 1e128;
-      powersOf10 = int16_t(powersOf10 + 128);
-    }
-    if (value >= 1e64) {
-      value /= 1e64;
-      powersOf10 = int16_t(powersOf10 + 64);
-    }
-#endif
-    if (value >= 1e32) {
-      value /= 1e32;
-      powersOf10 = int16_t(powersOf10 + 32);
-    }
-    if (value >= 1e16) {
-      value /= 1e16;
-      powersOf10 = int16_t(powersOf10 + 16);
-    }
-    if (value >= 1e8) {
-      value /= 1e8;
-      powersOf10 = int16_t(powersOf10 + 8);
-    }
-    if (value >= 1e4) {
-      value /= 1e4;
-      powersOf10 = int16_t(powersOf10 + 4);
-    }
-    if (value >= 1e2) {
-      value /= 1e2;
-      powersOf10 = int16_t(powersOf10 + 2);
-    }
-    if (value >= 1e1) {
-      value /= 1e1;
-      powersOf10 = int16_t(powersOf10 + 1);
-    }
-  }
-
-  if (value > 0 && value <= ARDUINOJSON_NEGATIVE_EXPONENTIATION_THRESHOLD) {
-#if ARDUINOJSON_DOUBLE_IS_64BITS
-    if (value < 1e-255) {
-      value *= 1e256;
-      powersOf10 = int16_t(powersOf10 - 256);
-    }
-    if (value < 1e-127) {
-      value *= 1e128;
-      powersOf10 = int16_t(powersOf10 - 128);
-    }
-    if (value < 1e-63) {
-      value *= 1e64;
-      powersOf10 = int16_t(powersOf10 - 64);
-    }
-#endif
-    if (value < 1e-31) {
-      value *= 1e32;
-      powersOf10 = int16_t(powersOf10 - 32);
-    }
-    if (value < 1e-15) {
-      value *= 1e16;
-      powersOf10 = int16_t(powersOf10 - 16);
-    }
-    if (value < 1e-7) {
-      value *= 1e8;
-      powersOf10 = int16_t(powersOf10 - 8);
-    }
-    if (value < 1e-3) {
-      value *= 1e4;
-      powersOf10 = int16_t(powersOf10 - 4);
-    }
-    if (value < 1e-1) {
-      value *= 1e2;
-      powersOf10 = int16_t(powersOf10 - 2);
-    }
-    if (value < 1e0) {
-      value *= 1e1;
-      powersOf10 = int16_t(powersOf10 - 1);
-    }
-  }
-
-  return powersOf10;
-}
-}
-}

src/ArduinoJson/Polyfills/parseFloat.hpp

@@ -26,8 +26,11 @@ inline T parseFloat(const char* s) {
   switch (*s) {
     case '-':
       negative_result = true;
+      s++;
+      break;
     case '+':
       s++;
+      break;
   }
 
   if (*s == 't') return 1;  // true

src/ArduinoJson/Polyfills/parseInteger.hpp

@@ -26,6 +26,8 @@ T parseInteger(const char *s) {
   switch (*s) {
     case '-':
       negative_result = true;
+      s++;
+      break;
     case '+':
       s++;
       break;

src/ArduinoJson/Serialization/FloatParts.hpp

@@ -0,0 +1,92 @@
+// Copyright Benoit Blanchon 2014-2017
+// MIT License
+//
+// Arduino JSON library
+// https://bblanchon.github.io/ArduinoJson/
+// If you like this project, please add a star!
+
+#pragma once
+
+#include "../Configuration.hpp"
+#include "../Polyfills/math.hpp"
+#include "../TypeTraits/FloatTraits.hpp"
+
+namespace ArduinoJson {
+namespace Internals {
+
+template <typename TFloat>
+struct FloatParts {
+  uint32_t integral;
+  uint32_t decimal;
+  int16_t exponent;
+  int8_t decimalPlaces;
+
+  FloatParts(TFloat value) {
+    uint32_t maxDecimalPart = sizeof(TFloat) >= 8 ? 1000000000 : 1000000;
+    decimalPlaces = sizeof(TFloat) >= 8 ? 9 : 6;
+
+    exponent = normalize(value);
+
+    integral = uint32_t(value);
+    // reduce number of decimal places by the number of integral places
+    for (uint32_t tmp = integral; tmp >= 10; tmp /= 10) {
+      maxDecimalPart /= 10;
+      decimalPlaces--;
+    }
+
+    TFloat remainder = (value - TFloat(integral)) * TFloat(maxDecimalPart);
+
+    decimal = uint32_t(remainder);
+    remainder = remainder - TFloat(decimal);
+
+    // rounding:
+    // increment by 1 if remainder >= 0.5
+    decimal += uint32_t(remainder * 2);
+    if (decimal >= maxDecimalPart) {
+      decimal = 0;
+      integral++;
+      if (exponent && integral >= 10) {
+        exponent++;
+        integral = 1;
+      }
+    }
+
+    // remove trailing zeros
+    while (decimal % 10 == 0 && decimalPlaces > 0) {
+      decimal /= 10;
+      decimalPlaces--;
+    }
+  }
+
+  static int16_t normalize(TFloat& value) {
+    typedef TypeTraits::FloatTraits<TFloat> traits;
+    int16_t powersOf10 = 0;
+
+    int8_t index = sizeof(TFloat) == 8 ? 8 : 5;
+    int bit = 1 << index;
+
+    if (value >= ARDUINOJSON_POSITIVE_EXPONENTIATION_THRESHOLD) {
+      for (; index >= 0; index--) {
+        if (value >= traits::positiveBinaryPowerOfTen(index)) {
+          value *= traits::negativeBinaryPowerOfTen(index);
+          powersOf10 = int16_t(powersOf10 + bit);
+        }
+        bit >>= 1;
+      }
+    }
+
+    if (value > 0 && value <= ARDUINOJSON_NEGATIVE_EXPONENTIATION_THRESHOLD) {
+      for (; index >= 0; index--) {
+        if (value < traits::negativeBinaryPowerOfTenPlusOne(index)) {
+          value *= traits::positiveBinaryPowerOfTen(index);
+          powersOf10 = int16_t(powersOf10 - bit);
+        }
+        bit >>= 1;
+      }
+    }
+
+    return powersOf10;
+  }
+};
+}
+}

src/ArduinoJson/Serialization/JsonSerializerImpl.hpp

@@ -90,7 +90,8 @@ inline void ArduinoJson::Internals::JsonSerializer<Writer>::serialize(
       return;
 
     case JSON_NEGATIVE_INTEGER:
-      writer.writeRaw('-');
+      writer.writeRaw('-');  // Falls through.
+
     case JSON_POSITIVE_INTEGER:
       writer.writeInteger(variant._content.asInteger);
       return;

src/ArduinoJson/Serialization/JsonWriter.hpp

@@ -9,12 +9,9 @@
 
 #include <stdint.h>
 #include "../Data/Encoding.hpp"
-#include "../Data/JsonFloat.hpp"
 #include "../Data/JsonInteger.hpp"
 #include "../Polyfills/attributes.hpp"
-#include "../Polyfills/math.hpp"
-#include "../Polyfills/normalize.hpp"
-#include "../TypeTraits/FloatTraits.hpp"
+#include "../Serialization/FloatParts.hpp"
 
 namespace ArduinoJson {
 namespace Internals {
@@ -28,10 +25,6 @@ namespace Internals {
 // indentation.
 template <typename Print>
 class JsonWriter {
-  static const uint8_t maxDecimalPlaces = sizeof(JsonFloat) >= 8 ? 9 : 6;
-  static const uint32_t maxDecimalPart =
-      sizeof(JsonFloat) >= 8 ? 1000000000 : 1000000;
-
  public:
   explicit JsonWriter(Print &sink) : _sink(sink), _length(0) {}
 
@@ -87,7 +80,8 @@ class JsonWriter {
     }
   }
 
-  void writeFloat(JsonFloat value) {
+  template <typename TFloat>
+  void writeFloat(TFloat value) {
     if (Polyfills::isNaN(value)) return writeRaw("NaN");
 
     if (value < 0.0) {
@@ -97,28 +91,27 @@ class JsonWriter {
 
     if (Polyfills::isInfinity(value)) return writeRaw("Infinity");
 
-    uint32_t integralPart, decimalPart;
-    int16_t powersOf10;
-    splitFloat(value, integralPart, decimalPart, powersOf10);
+    FloatParts<TFloat> parts(value);
 
-    writeInteger(integralPart);
-    if (decimalPart) writeDecimals(decimalPart, maxDecimalPlaces);
+    writeInteger(parts.integral);
+    if (parts.decimalPlaces) writeDecimals(parts.decimal, parts.decimalPlaces);
 
-    if (powersOf10 < 0) {
+    if (parts.exponent < 0) {
       writeRaw("e-");
-      writeInteger(-powersOf10);
+      writeInteger(-parts.exponent);
     }
 
-    if (powersOf10 > 0) {
+    if (parts.exponent > 0) {
       writeRaw('e');
-      writeInteger(powersOf10);
+      writeInteger(parts.exponent);
     }
   }
 
   template <typename UInt>
   void writeInteger(UInt value) {
     char buffer[22];
-    char *ptr = buffer + sizeof(buffer) - 1;
+    char *end = buffer + sizeof(buffer) - 1;
+    char *ptr = end;
 
     *ptr = 0;
     do {
@@ -130,15 +123,9 @@ class JsonWriter {
   }
 
   void writeDecimals(uint32_t value, int8_t width) {
-    // remove trailing zeros
-    while (value % 10 == 0 && width > 0) {
-      value /= 10;
-      width--;
-    }
-
     // buffer should be big enough for all digits, the dot and the null
     // terminator
-    char buffer[maxDecimalPlaces + 2];
+    char buffer[16];
     char *ptr = buffer + sizeof(buffer) - 1;
 
     // write the string in reverse order
@@ -166,30 +153,6 @@ class JsonWriter {
 
  private:
   JsonWriter &operator=(const JsonWriter &);  // cannot be assigned
-
-  void splitFloat(JsonFloat value, uint32_t &integralPart,
-                  uint32_t &decimalPart, int16_t &powersOf10) {
-    powersOf10 = Polyfills::normalize(value);
-
-    integralPart = uint32_t(value);
-    JsonFloat remainder = value - JsonFloat(integralPart);
-
-    remainder *= maxDecimalPart;
-    decimalPart = uint32_t(remainder);
-    remainder = remainder - JsonFloat(decimalPart);
-
-    // rounding:
-    // increment by 1 if remainder >= 0.5
-    decimalPart += uint32_t(remainder * 2);
-    if (decimalPart >= maxDecimalPart) {
-      decimalPart = 0;
-      integralPart++;
-      if (powersOf10 && integralPart >= 10) {
-        powersOf10++;
-        integralPart = 1;
-      }
-    }
-  }
 };
 }
 }

src/ArduinoJson/StaticJsonBuffer.hpp

@@ -9,16 +9,6 @@
 
 #include "JsonBufferBase.hpp"
 
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic push
-#endif
-#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-#endif
-
 namespace ArduinoJson {
 
 class StaticJsonBufferBase : public JsonBufferBase<StaticJsonBufferBase> {
@@ -81,6 +71,9 @@ class StaticJsonBufferBase : public JsonBufferBase<StaticJsonBufferBase> {
     return String(this);
   }
 
+ protected:
+  ~StaticJsonBufferBase() {}
+
  private:
   void alignNextAlloc() {
     _size = round_size_up(_size);
@@ -101,6 +94,16 @@ class StaticJsonBufferBase : public JsonBufferBase<StaticJsonBufferBase> {
   size_t _size;
 };
 
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic push
+#endif
+#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
+#endif
+
 // Implements a JsonBuffer with fixed memory allocation.
 // The template paramenter CAPACITY specifies the capacity of the buffer in
 // bytes.

src/ArduinoJson/StringTraits/FlashString.hpp

@@ -34,15 +34,15 @@ struct StringTraits<const __FlashStringHelper*, void> {
   };
 
   static bool equals(const __FlashStringHelper* str, const char* expected) {
-    return strcmp_P(expected, (PGM_P)str) == 0;
+    return strcmp_P(expected, (const char*)str) == 0;
   }
 
   template <typename Buffer>
   static char* duplicate(const __FlashStringHelper* str, Buffer* buffer) {
     if (!str) return NULL;
-    size_t size = strlen_P((PGM_P)str) + 1;
+    size_t size = strlen_P((const char*)str) + 1;
     void* dup = buffer->alloc(size);
-    if (dup != NULL) memcpy_P(dup, (PGM_P)str, size);
+    if (dup != NULL) memcpy_P(dup, (const char*)str, size);
     return static_cast<char*>(dup);
   }
 

src/ArduinoJson/TypeTraits/FloatTraits.hpp

@@ -18,7 +18,6 @@ namespace TypeTraits {
 template <typename T, size_t = sizeof(T)>
 struct FloatTraits {};
 
-#if ARDUINOJSON_DOUBLE_IS_64BITS
 template <typename T>
 struct FloatTraits<T, 8 /*64bits*/> {
   typedef int64_t mantissa_type;
@@ -31,29 +30,65 @@ struct FloatTraits<T, 8 /*64bits*/> {
 
   template <typename TExponent>
   static T make_float(T m, TExponent e) {
-    if (e >= 0)
-      return m * (e & 1 ? 1e1 : 1) * (e & 2 ? 1e2 : 1) * (e & 4 ? 1e4 : 1) *
-             (e & 8 ? 1e8 : 1) * (e & 16 ? 1e16 : 1) * (e & 32 ? 1e32 : 1) *
-             (e & 64 ? 1e64 : 1) * (e & 128 ? 1e128 : 1) *
-             (e & 256 ? 1e256 : 1);
-    e = TExponent(-e);
-    return m * (e & 1 ? 1e-1 : 1) * (e & 2 ? 1e-2 : 1) * (e & 4 ? 1e-4 : 1) *
-           (e & 8 ? 1e-8 : 1) * (e & 16 ? 1e-16 : 1) * (e & 32 ? 1e-32 : 1) *
-           (e & 64 ? 1e-64 : 1) * (e & 128 ? 1e-128 : 1) *
-           (e & 256 ? 1e-256 : 1);
+    if (e > 0) {
+      for (uint8_t index = 0; e != 0; index++) {
+        if (e & 1) m *= positiveBinaryPowerOfTen(index);
+        e >>= 1;
+      }
+    } else {
+      e = TExponent(-e);
+      for (uint8_t index = 0; e != 0; index++) {
+        if (e & 1) m *= negativeBinaryPowerOfTen(index);
+        e >>= 1;
+      }
+    }
+    return m;
+  }
+
+  static T positiveBinaryPowerOfTen(int index) {
+    static T factors[] = {
+        1e1, 1e2, 1e4, 1e8, 1e16, 1e32,
+        // workaround to support platforms with single precision literals
+        forge(0x4D384F03, 0xE93FF9F5), forge(0x5A827748, 0xF9301D32),
+        forge(0x75154FDD, 0x7F73BF3C)};
+    return factors[index];
+  }
+
+  static T negativeBinaryPowerOfTen(int index) {
+    static T factors[] = {
+        1e-1, 1e-2, 1e-4, 1e-8, 1e-16, 1e-32,
+        // workaround to support platforms with single precision literals
+        forge(0x32A50FFD, 0x44F4A73D), forge(0x255BBA08, 0xCF8C979D),
+        forge(0x0AC80628, 0x64AC6F43)};
+    return factors[index];
+  }
+
+  static T negativeBinaryPowerOfTenPlusOne(int index) {
+    static T factors[] = {
+        1e0, 1e-1, 1e-3, 1e-7, 1e-15, 1e-31,
+        // workaround to support platforms with single precision literals
+        forge(0x32DA53FC, 0x9631D10D), forge(0x25915445, 0x81B7DEC2),
+        forge(0x0AFE07B2, 0x7DD78B14)};
+    return factors[index];
   }
 
   static T nan() {
-    uint64_t x = uint64_t(0x7ff8) << 48;
-    return *reinterpret_cast<T*>(&x);
+    return forge(0x7ff80000, 0x00000000);
   }
 
   static T inf() {
-    uint64_t x = uint64_t(0x7ff0) << 48;
-    return *reinterpret_cast<T*>(&x);
+    return forge(0x7ff00000, 0x00000000);
+  }
+
+  static T forge(uint32_t msb, uint32_t lsb) {
+    union {
+      uint64_t integerBits;
+      T floatBits;
+    };
+    integerBits = (uint64_t(msb) << 32) | lsb;
+    return floatBits;
   }
 };
-#endif
 
 template <typename T>
 struct FloatTraits<T, 4 /*32bits*/> {
@@ -67,22 +102,51 @@ struct FloatTraits<T, 4 /*32bits*/> {
 
   template <typename TExponent>
   static T make_float(T m, TExponent e) {
-    if (e > 0)
-      return m * (e & 1 ? 1e1f : 1) * (e & 2 ? 1e2f : 1) * (e & 4 ? 1e4f : 1) *
-             (e & 8 ? 1e8f : 1) * (e & 16 ? 1e16f : 1) * (e & 32 ? 1e32f : 1);
-    e = -e;
-    return m * (e & 1 ? 1e-1f : 1) * (e & 2 ? 1e-2f : 1) * (e & 4 ? 1e-4f : 1) *
-           (e & 8 ? 1e-8f : 1) * (e & 16 ? 1e-16f : 1) * (e & 32 ? 1e-32f : 1);
+    if (e > 0) {
+      for (uint8_t index = 0; e != 0; index++) {
+        if (e & 1) m *= positiveBinaryPowerOfTen(index);
+        e >>= 1;
+      }
+    } else {
+      e = -e;
+      for (uint8_t index = 0; e != 0; index++) {
+        if (e & 1) m *= negativeBinaryPowerOfTen(index);
+        e >>= 1;
+      }
+    }
+    return m;
+  }
+
+  static T positiveBinaryPowerOfTen(int index) {
+    static T factors[] = {1e1f, 1e2f, 1e4f, 1e8f, 1e16f, 1e32f};
+    return factors[index];
+  }
+
+  static T negativeBinaryPowerOfTen(int index) {
+    static T factors[] = {1e-1f, 1e-2f, 1e-4f, 1e-8f, 1e-16f, 1e-32f};
+    return factors[index];
+  }
+
+  static T negativeBinaryPowerOfTenPlusOne(int index) {
+    static T factors[] = {1e0f, 1e-1f, 1e-3f, 1e-7f, 1e-15f, 1e-31f};
+    return factors[index];
+  }
+
+  static T forge(uint32_t bits) {
+    union {
+      uint32_t integerBits;
+      T floatBits;
+    };
+    integerBits = bits;
+    return floatBits;
   }
 
   static T nan() {
-    uint32_t x = 0x7fc00000;
-    return *reinterpret_cast<T*>(&x);
+    return forge(0x7fc00000);
   }
 
   static T inf() {
-    uint32_t x = 0x7f800000;
-    return *reinterpret_cast<T*>(&x);
+    return forge(0x7f800000);
   }
 };
 }

src/ArduinoJson/TypeTraits/IsVariant.hpp

@@ -0,0 +1,20 @@
+// Copyright Benoit Blanchon 2014-2017
+// MIT License
+//
+// Arduino JSON library
+// https://bblanchon.github.io/ArduinoJson/
+// If you like this project, please add a star!
+
+#pragma once
+
+#include "IsBaseOf.hpp"
+
+namespace ArduinoJson {
+namespace TypeTraits {
+
+class JsonVariantTag {};
+
+template <typename T>
+struct IsVariant : IsBaseOf<JsonVariantTag, T> {};
+}
+}

test/CMakeLists.txt

@@ -19,13 +19,14 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "(GNU|Clang)")
 		-Wformat=2
 		-Winit-self
 		-Wmissing-include-dirs
-		-Wparentheses
 		-Wnon-virtual-dtor
 		-Wold-style-cast
 		-Woverloaded-virtual
+		-Wparentheses
 		-Wredundant-decls
 		-Wshadow
 		-Wsign-promo
+		-Wstrict-aliasing
 		-Wstrict-overflow=5
 		-Wundef
 	)

test/DynamicJsonBuffer/alloc.cpp

@@ -46,7 +46,7 @@ TEST_CASE("DynamicJsonBuffer::alloc()") {
     REQUIRE(allocatorLog.str() == "A1A2FF");
   }
 
-  SECTION("Keeps increasing allocation size after clear") {
+  SECTION("Resets allocation size after clear()") {
     allocatorLog.str("");
     {
       DynamicJsonBufferBase<SpyingAllocator> buffer(1);
@@ -55,7 +55,7 @@ TEST_CASE("DynamicJsonBuffer::alloc()") {
       buffer.clear();
       buffer.alloc(1);
     }
-    REQUIRE(allocatorLog.str() == "A1A2FFA4F");
+    REQUIRE(allocatorLog.str() == "A1A2FFA1F");
   }
 
   SECTION("Makes a big allocation when needed") {

test/IntegrationTests/CMakeLists.txt

@@ -10,5 +10,12 @@ add_executable(IntegrationTests
 	round_trip.cpp
 )
 
+if(CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+	target_compile_options(IntegrationTests
+		PUBLIC
+		-fsingle-precision-constant # issue 544
+	)
+endif()
+
 target_link_libraries(IntegrationTests catch)
 add_test(IntegrationTests IntegrationTests)

test/JsonWriter/writeFloat.cpp

@@ -14,7 +14,8 @@
 
 using namespace ArduinoJson::Internals;
 
-void check(double input, const std::string& expected) {
+template <typename TFloat>
+void check(TFloat input, const std::string& expected) {
   std::string output;
   DynamicStringBuilder<std::string> sb(output);
   JsonWriter<DynamicStringBuilder<std::string> > writer(sb);
@@ -23,83 +24,97 @@ void check(double input, const std::string& expected) {
   CHECK(expected == output);
 }
 
-TEST_CASE("JsonWriter::writeFloat()") {
+TEST_CASE("JsonWriter::writeFloat(double)") {
   SECTION("Pi") {
-    check(3.14159265359, "3.141592654");
+    check<double>(3.14159265359, "3.141592654");
   }
 
   SECTION("Signaling NaN") {
     double nan = std::numeric_limits<double>::signaling_NaN();
-    check(nan, "NaN");
+    check<double>(nan, "NaN");
   }
 
   SECTION("Quiet NaN") {
     double nan = std::numeric_limits<double>::quiet_NaN();
-    check(nan, "NaN");
+    check<double>(nan, "NaN");
   }
 
   SECTION("Infinity") {
     double inf = std::numeric_limits<double>::infinity();
-    check(inf, "Infinity");
-    check(-inf, "-Infinity");
+    check<double>(inf, "Infinity");
+    check<double>(-inf, "-Infinity");
   }
 
   SECTION("Zero") {
-    check(0.0, "0");
-    check(-0.0, "0");
+    check<double>(0.0, "0");
+    check<double>(-0.0, "0");
   }
 
   SECTION("Espilon") {
-    check(2.2250738585072014E-308, "2.225073859e-308");
-    check(-2.2250738585072014E-308, "-2.225073859e-308");
+    check<double>(2.2250738585072014E-308, "2.225073859e-308");
+    check<double>(-2.2250738585072014E-308, "-2.225073859e-308");
   }
 
   SECTION("Max double") {
-    check(1.7976931348623157E+308, "1.797693135e308");
-    check(-1.7976931348623157E+308, "-1.797693135e308");
+    check<double>(1.7976931348623157E+308, "1.797693135e308");
+    check<double>(-1.7976931348623157E+308, "-1.797693135e308");
   }
 
   SECTION("Big exponent") {
     // this test increases coverage of normalize()
-    check(1e255, "1e255");
-    check(1e-255, "1e-255");
+    check<double>(1e255, "1e255");
+    check<double>(1e-255, "1e-255");
   }
 
   SECTION("Exponentation when <= 1e-5") {
-    check(1e-4, "0.0001");
-    check(1e-5, "1e-5");
+    check<double>(1e-4, "0.0001");
+    check<double>(1e-5, "1e-5");
 
-    check(-1e-4, "-0.0001");
-    check(-1e-5, "-1e-5");
+    check<double>(-1e-4, "-0.0001");
+    check<double>(-1e-5, "-1e-5");
   }
 
   SECTION("Exponentation when >= 1e7") {
-    check(9999999.999, "9999999.999");
-    check(10000000, "1e7");
+    check<double>(9999999.999, "9999999.999");
+    check<double>(10000000.0, "1e7");
 
-    check(-9999999.999, "-9999999.999");
-    check(-10000000, "-1e7");
+    check<double>(-9999999.999, "-9999999.999");
+    check<double>(-10000000.0, "-1e7");
   }
 
   SECTION("Rounding when too many decimals") {
-    check(0.000099999999999, "0.0001");
-    check(0.0000099999999999, "1e-5");
-    check(0.9999999996, "1");
+    check<double>(0.000099999999999, "0.0001");
+    check<double>(0.0000099999999999, "1e-5");
+    check<double>(0.9999999996, "1");
   }
 
   SECTION("9 decimal places") {
-    check(0.100000001, "0.100000001");
-    check(0.999999999, "0.999999999");
+    check<double>(0.100000001, "0.100000001");
+    check<double>(0.999999999, "0.999999999");
 
-    check(9.000000001, "9.000000001");
-    check(9.999999999, "9.999999999");
+    check<double>(9.000000001, "9.000000001");
+    check<double>(9.999999999, "9.999999999");
   }
 
   SECTION("10 decimal places") {
-    check(0.1000000001, "0.1");
-    check(0.9999999999, "1");
+    check<double>(0.1000000001, "0.1");
+    check<double>(0.9999999999, "1");
 
-    check(9.0000000001, "9");
-    check(9.9999999999, "10");
+    check<double>(9.0000000001, "9");
+    check<double>(9.9999999999, "10");
+  }
+}
+
+TEST_CASE("JsonWriter::writeFloat(float)") {
+  SECTION("Pi") {
+    check<float>(3.14159265359f, "3.141593");
+  }
+
+  SECTION("999.9") {  // issue #543
+    check<float>(999.9f, "999.9");
+  }
+
+  SECTION("24.3") {  // # issue #588
+    check<float>(24.3f, "24.3");
   }
 }

test/Misc/CMakeLists.txt

@@ -7,6 +7,7 @@
 
 add_executable(MiscTests 
 	deprecated.cpp
+	FloatParts.cpp
 	std_stream.cpp
 	std_string.cpp
 	StringBuilder.cpp

test/Misc/FloatParts.cpp

@@ -0,0 +1,47 @@
+// Copyright Benoit Blanchon 2014-2017
+// MIT License
+//
+// Arduino JSON library
+// https://bblanchon.github.io/ArduinoJson/
+// If you like this project, please add a star!
+
+#include <ArduinoJson/Serialization/FloatParts.hpp>
+#include <catch.hpp>
+
+using namespace ArduinoJson::Internals;
+
+TEST_CASE("FloatParts<double>") {
+  SECTION("1.7976931348623157E+308") {
+    FloatParts<double> parts(1.7976931348623157E+308);
+    REQUIRE(parts.integral == 1);
+    REQUIRE(parts.decimal == 797693135);
+    REQUIRE(parts.decimalPlaces == 9);
+    REQUIRE(parts.exponent == 308);
+  }
+
+  SECTION("4.94065645841247e-324") {
+    FloatParts<double> parts(4.94065645841247e-324);
+    REQUIRE(parts.integral == 4);
+    REQUIRE(parts.decimal == 940656458);
+    REQUIRE(parts.decimalPlaces == 9);
+    REQUIRE(parts.exponent == -324);
+  }
+}
+
+TEST_CASE("FloatParts<float>") {
+  SECTION("3.4E+38") {
+    FloatParts<float> parts(3.4E+38f);
+    REQUIRE(parts.integral == 3);
+    REQUIRE(parts.decimal == 4);
+    REQUIRE(parts.decimalPlaces == 1);
+    REQUIRE(parts.exponent == 38);
+  }
+
+  SECTION("1.17549435e−38") {
+    FloatParts<float> parts(1.17549435e-38f);
+    REQUIRE(parts.integral == 1);
+    REQUIRE(parts.decimal == 175494);
+    REQUIRE(parts.decimalPlaces == 6);
+    REQUIRE(parts.exponent == -38);
+  }
+}