Moved ancillary files to extras/ (fixes #1011)

extras/tests/CMakeLists.txt

@@ -0,0 +1,90 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_subdirectory(catch)
+
+if(CMAKE_CXX_COMPILER_ID MATCHES "(GNU|Clang)")
+	add_compile_options(
+		-pedantic
+		-Wall
+		-Wcast-align
+		-Wcast-qual
+		-Wconversion
+		-Wctor-dtor-privacy
+		-Wdisabled-optimization
+		-Werror
+		-Wextra
+		-Wformat=2
+		-Winit-self
+		-Wmissing-include-dirs
+		-Wnon-virtual-dtor
+		-Wold-style-cast
+		-Woverloaded-virtual
+		-Wparentheses
+		-Wredundant-decls
+		-Wshadow
+		-Wsign-promo
+		-Wstrict-aliasing
+		-Wundef
+	)
+
+	if(NOT MINGW)
+		add_compile_options(
+			-std=c++98
+		)
+	endif()
+endif()
+
+if(CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+	add_compile_options(
+		-Wstrict-null-sentinel
+		-Wno-vla # Allow VLA in tests
+	)
+	add_definitions(-DHAS_VARIABLE_LENGTH_ARRAY)
+
+	if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 4.5)
+		add_compile_options(-Wlogical-op) # the flag exists in 4.4 but is buggy
+	endif()
+
+	if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 4.6)
+		add_compile_options(-Wnoexcept)
+	endif()
+endif()
+
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+	add_compile_options(
+		-Wc++11-compat
+		-Wdeprecated-register
+		-Wno-vla-extension # Allow VLA in tests
+	)
+	add_definitions(
+		-DHAS_VARIABLE_LENGTH_ARRAY
+		-DSUBSCRIPT_CONFLICTS_WITH_BUILTIN_OPERATOR
+	)
+endif()
+
+if(MSVC)
+	add_definitions(-D_CRT_SECURE_NO_WARNINGS)
+	add_compile_options(
+		/W4 # Set warning level
+		/WX # Treats all compiler warnings as errors.
+	)
+endif()
+
+add_subdirectory(ElementProxy)
+add_subdirectory(IntegrationTests)
+add_subdirectory(JsonArray)
+add_subdirectory(JsonDeserializer)
+add_subdirectory(JsonDocument)
+add_subdirectory(JsonObject)
+add_subdirectory(JsonSerializer)
+add_subdirectory(JsonVariant)
+add_subdirectory(MemberProxy)
+add_subdirectory(MemoryPool)
+add_subdirectory(Misc)
+add_subdirectory(MixedConfiguration)
+add_subdirectory(MsgPackDeserializer)
+add_subdirectory(MsgPackSerializer)
+add_subdirectory(Numbers)
+add_subdirectory(TextFormatter)

extras/tests/ElementProxy/CMakeLists.txt

@@ -0,0 +1,15 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(ElementProxyTests
+	add.cpp
+	clear.cpp
+	compare.cpp
+	remove.cpp
+	set.cpp
+	size.cpp
+)
+
+target_link_libraries(ElementProxyTests catch)
+add_test(ElementProxy ElementProxyTests)

extras/tests/ElementProxy/add.cpp

@@ -0,0 +1,26 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("ElementProxy::add()") {
+  DynamicJsonDocument doc(4096);
+  doc.addElement();
+  ElementProxy<JsonDocument&> ep = doc[0];
+
+  SECTION("add(int)") {
+    ep.add(42);
+
+    REQUIRE(doc.as<std::string>() == "[[42]]");
+  }
+
+  SECTION("add(const char*)") {
+    ep.add("world");
+
+    REQUIRE(doc.as<std::string>() == "[[\"world\"]]");
+  }
+}

extras/tests/ElementProxy/clear.cpp

@@ -0,0 +1,28 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("ElementProxy::clear()") {
+  DynamicJsonDocument doc(4096);
+  doc.addElement();
+  ElementProxy<JsonDocument&> ep = doc[0];
+
+  SECTION("size goes back to zero") {
+    ep.add(42);
+    ep.clear();
+
+    REQUIRE(ep.size() == 0);
+  }
+
+  SECTION("isNull() return true") {
+    ep.add("hello");
+    ep.clear();
+
+    REQUIRE(ep.isNull() == true);
+  }
+}

extras/tests/ElementProxy/compare.cpp

@@ -0,0 +1,28 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("ElementProxy::operator==()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("same value") {
+    doc.add(1);
+    doc.add(1);
+
+    REQUIRE(doc[0] == doc[1]);
+    REQUIRE_FALSE(doc[0] != doc[1]);
+  }
+
+  SECTION("different values") {
+    doc.add(1);
+    doc.add(2);
+
+    REQUIRE_FALSE(doc[0] == doc[1]);
+    REQUIRE(doc[0] != doc[1]);
+  }
+}

extras/tests/ElementProxy/remove.cpp

@@ -0,0 +1,56 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("ElementProxy::remove()") {
+  DynamicJsonDocument doc(4096);
+  doc.addElement();
+  ElementProxy<JsonDocument&> ep = doc[0];
+
+  SECTION("remove(int)") {
+    ep.add(1);
+    ep.add(2);
+    ep.add(3);
+
+    ep.remove(1);
+
+    REQUIRE(ep.as<std::string>() == "[1,3]");
+  }
+
+  SECTION("remove(const char *)") {
+    ep["a"] = 1;
+    ep["b"] = 2;
+
+    ep.remove("a");
+
+    REQUIRE(ep.as<std::string>() == "{\"b\":2}");
+  }
+
+  SECTION("remove(std::string)") {
+    ep["a"] = 1;
+    ep["b"] = 2;
+
+    ep.remove(std::string("b"));
+
+    REQUIRE(ep.as<std::string>() == "{\"a\":1}");
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("remove(vla)") {
+    ep["a"] = 1;
+    ep["b"] = 2;
+
+    int i = 4;
+    char vla[i];
+    strcpy(vla, "b");
+    ep.remove(vla);
+
+    REQUIRE(ep.as<std::string>() == "{\"a\":1}");
+  }
+#endif
+}

extras/tests/ElementProxy/set.cpp

@@ -0,0 +1,26 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("ElementProxy::set()") {
+  DynamicJsonDocument doc(4096);
+  doc.addElement();
+  ElementProxy<JsonDocument&> ep = doc[0];
+
+  SECTION("set(int)") {
+    ep.set(42);
+
+    REQUIRE(doc.as<std::string>() == "[42]");
+  }
+
+  SECTION("set(const char*)") {
+    ep.set("world");
+
+    REQUIRE(doc.as<std::string>() == "[\"world\"]");
+  }
+}

extras/tests/ElementProxy/size.cpp

@@ -0,0 +1,30 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("ElementProxy::size()") {
+  DynamicJsonDocument doc(4096);
+  doc.addElement();
+  ElementProxy<JsonDocument&> ep = doc[0];
+
+  SECTION("returns 0") {
+    REQUIRE(ep.size() == 0);
+  }
+
+  SECTION("as an array, returns 2") {
+    ep.add(1);
+    ep.add(2);
+    REQUIRE(ep.size() == 2);
+  }
+
+  SECTION("as an object, returns 2") {
+    ep["a"] = 1;
+    ep["b"] = 2;
+    REQUIRE(ep.size() == 2);
+  }
+}

extras/tests/IntegrationTests/CMakeLists.txt

@@ -0,0 +1,19 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(IntegrationTests
+	gbathree.cpp
+	issue772.cpp
+	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)

extras/tests/IntegrationTests/gbathree.cpp

@@ -0,0 +1,210 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("Gbathree") {
+  DynamicJsonDocument doc(4096);
+
+  DeserializationError error = deserializeJson(
+      doc,
+      "{\"protocol_name\":\"fluorescence\",\"repeats\":1,\"wait\":0,"
+      "\"averages\":1,\"measurements\":3,\"meas2_light\":15,\"meas1_"
+      "baseline\":0,\"act_light\":20,\"pulsesize\":25,\"pulsedistance\":"
+      "10000,\"actintensity1\":50,\"actintensity2\":255,\"measintensity\":"
+      "255,\"calintensity\":255,\"pulses\":[50,50,50],\"act\":[2,1,2,2],"
+      "\"red\":[2,2,2,2],\"detectors\":[[34,34,34,34],[34,34,34,34],[34,"
+      "34,34,34],[34,34,34,34]],\"alta\":[2,2,2,2],\"altb\":[2,2,2,2],"
+      "\"measlights\":[[15,15,15,15],[15,15,15,15],[15,15,15,15],[15,15,"
+      "15,15]],\"measlights2\":[[15,15,15,15],[15,15,15,15],[15,15,15,15],"
+      "[15,15,15,15]],\"altc\":[2,2,2,2],\"altd\":[2,2,2,2]}");
+  JsonObject root = doc.as<JsonObject>();
+
+  SECTION("Success") {
+    REQUIRE(error == DeserializationError::Ok);
+  }
+
+  SECTION("ProtocolName") {
+    REQUIRE("fluorescence" == root["protocol_name"]);
+  }
+
+  SECTION("Repeats") {
+    REQUIRE(1 == root["repeats"]);
+  }
+
+  SECTION("Wait") {
+    REQUIRE(0 == root["wait"]);
+  }
+
+  SECTION("Measurements") {
+    REQUIRE(3 == root["measurements"]);
+  }
+
+  SECTION("Meas2_Light") {
+    REQUIRE(15 == root["meas2_light"]);
+  }
+
+  SECTION("Meas1_Baseline") {
+    REQUIRE(0 == root["meas1_baseline"]);
+  }
+
+  SECTION("Act_Light") {
+    REQUIRE(20 == root["act_light"]);
+  }
+
+  SECTION("Pulsesize") {
+    REQUIRE(25 == root["pulsesize"]);
+  }
+
+  SECTION("Pulsedistance") {
+    REQUIRE(10000 == root["pulsedistance"]);
+  }
+
+  SECTION("Actintensity1") {
+    REQUIRE(50 == root["actintensity1"]);
+  }
+
+  SECTION("Actintensity2") {
+    REQUIRE(255 == root["actintensity2"]);
+  }
+
+  SECTION("Measintensity") {
+    REQUIRE(255 == root["measintensity"]);
+  }
+
+  SECTION("Calintensity") {
+    REQUIRE(255 == root["calintensity"]);
+  }
+
+  SECTION("Pulses") {
+    // "pulses":[50,50,50]
+
+    JsonArray array = root["pulses"];
+    REQUIRE(array.isNull() == false);
+
+    REQUIRE(3 == array.size());
+
+    for (size_t i = 0; i < 3; i++) {
+      REQUIRE(50 == array[i]);
+    }
+  }
+
+  SECTION("Act") {
+    // "act":[2,1,2,2]
+
+    JsonArray array = root["act"];
+    REQUIRE(array.isNull() == false);
+
+    REQUIRE(4 == array.size());
+    REQUIRE(2 == array[0]);
+    REQUIRE(1 == array[1]);
+    REQUIRE(2 == array[2]);
+    REQUIRE(2 == array[3]);
+  }
+
+  SECTION("Detectors") {
+    // "detectors":[[34,34,34,34],[34,34,34,34],[34,34,34,34],[34,34,34,34]]
+
+    JsonArray array = root["detectors"];
+    REQUIRE(array.isNull() == false);
+    REQUIRE(4 == array.size());
+
+    for (size_t i = 0; i < 4; i++) {
+      JsonArray nestedArray = array[i];
+      REQUIRE(4 == nestedArray.size());
+
+      for (size_t j = 0; j < 4; j++) {
+        REQUIRE(34 == nestedArray[j]);
+      }
+    }
+  }
+
+  SECTION("Alta") {
+    // alta:[2,2,2,2]
+
+    JsonArray array = root["alta"];
+    REQUIRE(array.isNull() == false);
+
+    REQUIRE(4 == array.size());
+
+    for (size_t i = 0; i < 4; i++) {
+      REQUIRE(2 == array[i]);
+    }
+  }
+
+  SECTION("Altb") {
+    // altb:[2,2,2,2]
+
+    JsonArray array = root["altb"];
+    REQUIRE(array.isNull() == false);
+
+    REQUIRE(4 == array.size());
+
+    for (size_t i = 0; i < 4; i++) {
+      REQUIRE(2 == array[i]);
+    }
+  }
+
+  SECTION("Measlights") {
+    // "measlights":[[15,15,15,15],[15,15,15,15],[15,15,15,15],[15,15,15,15]]
+
+    JsonArray array = root["measlights"];
+    REQUIRE(array.isNull() == false);
+    REQUIRE(4 == array.size());
+
+    for (size_t i = 0; i < 4; i++) {
+      JsonArray nestedArray = array[i];
+
+      REQUIRE(4 == nestedArray.size());
+
+      for (size_t j = 0; j < 4; j++) {
+        REQUIRE(15 == nestedArray[j]);
+      }
+    }
+  }
+
+  SECTION("Measlights2") {
+    // "measlights2":[[15,15,15,15],[15,15,15,15],[15,15,15,15],[15,15,15,15]]
+
+    JsonArray array = root["measlights2"];
+    REQUIRE(array.isNull() == false);
+    REQUIRE(4 == array.size());
+
+    for (size_t i = 0; i < 4; i++) {
+      JsonArray nestedArray = array[i];
+      REQUIRE(4 == nestedArray.size());
+
+      for (size_t j = 0; j < 4; j++) {
+        REQUIRE(15 == nestedArray[j]);
+      }
+    }
+  }
+
+  SECTION("Altc") {
+    // altc:[2,2,2,2]
+
+    JsonArray array = root["altc"];
+    REQUIRE(array.isNull() == false);
+
+    REQUIRE(4 == array.size());
+
+    for (size_t i = 0; i < 4; i++) {
+      REQUIRE(2 == array[i]);
+    }
+  }
+
+  SECTION("Altd") {
+    // altd:[2,2,2,2]
+
+    JsonArray array = root["altd"];
+    REQUIRE(array.isNull() == false);
+
+    REQUIRE(4 == array.size());
+
+    for (size_t i = 0; i < 4; i++) {
+      REQUIRE(2 == array[i]);
+    }
+  }
+}

extras/tests/IntegrationTests/issue772.cpp

@@ -0,0 +1,28 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+// https://github.com/bblanchon/ArduinoJson/issues/772
+
+TEST_CASE("Issue772") {
+  DynamicJsonDocument doc1(4096);
+  DynamicJsonDocument doc2(4096);
+  DeserializationError err;
+  std::string data =
+      "{\"state\":{\"reported\":{\"timestamp\":\"2018-07-02T09:40:12Z\","
+      "\"mac\":\"2C3AE84FC076\",\"firmwareVersion\":\"v0.2.7-5-gf4d4d78\","
+      "\"visibleLight\":261,\"infraRed\":255,\"ultraViolet\":0.02,"
+      "\"Temperature\":26.63,\"Pressure\":101145.7,\"Humidity\":54.79883,"
+      "\"Vbat\":4.171261,\"soilMoisture\":0,\"ActB\":0}}}";
+  err = deserializeJson(doc1, data);
+  REQUIRE(err == DeserializationError::Ok);
+
+  data = "";
+  serializeMsgPack(doc1, data);
+  err = deserializeMsgPack(doc2, data);
+
+  REQUIRE(err == DeserializationError::Ok);
+}

extras/tests/IntegrationTests/round_trip.cpp

@@ -0,0 +1,82 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+void check(std::string originalJson) {
+  DynamicJsonDocument doc(16384);
+
+  std::string prettyJson;
+  deserializeJson(doc, originalJson);
+  serializeJsonPretty(doc, prettyJson);
+
+  std::string finalJson;
+  deserializeJson(doc, originalJson);
+  serializeJson(doc, finalJson);
+
+  REQUIRE(originalJson == finalJson);
+}
+
+TEST_CASE("Round Trip: parse -> prettyPrint -> parse -> print") {
+  SECTION("OpenWeatherMap") {
+    check(
+        "{\"coord\":{\"lon\":145.77,\"lat\":-16.92},\"sys\":{\"type\":1,\"id\":"
+        "8166,\"message\":0.1222,\"country\":\"AU\",\"sunrise\":1414784325,"
+        "\"sunset\":1414830137},\"weather\":[{\"id\":801,\"main\":\"Clouds\","
+        "\"description\":\"few clouds\",\"icon\":\"02n\"}],\"base\":\"cmc "
+        "stations\",\"main\":{\"temp\":296.15,\"pressure\":1014,\"humidity\":"
+        "83,\"temp_min\":296.15,\"temp_max\":296.15},\"wind\":{\"speed\":2.22,"
+        "\"deg\":114.501},\"clouds\":{\"all\":20},\"dt\":1414846800,\"id\":"
+        "2172797,\"name\":\"Cairns\",\"cod\":200}");
+  }
+
+  SECTION("YahooQueryLanguage") {
+    check(
+        "{\"query\":{\"count\":40,\"created\":\"2014-11-01T14:16:49Z\","
+        "\"lang\":\"fr-FR\",\"results\":{\"item\":[{\"title\":\"Burkina army "
+        "backs Zida as interim leader\"},{\"title\":\"British jets intercept "
+        "Russian bombers\"},{\"title\":\"Doubts chip away at nation's most "
+        "trusted agencies\"},{\"title\":\"Cruise ship stuck off Norway, no "
+        "damage\"},{\"title\":\"U.S. military launches 10 air strikes in "
+        "Syria, Iraq\"},{\"title\":\"Blackout hits Bangladesh as line from "
+        "India fails\"},{\"title\":\"Burkina Faso president in Ivory Coast "
+        "after ouster\"},{\"title\":\"Kurds in Turkey rally to back city "
+        "besieged by IS\"},{\"title\":\"A majority of Scots would vote for "
+        "independence now:poll\"},{\"title\":\"Tunisia elections possible "
+        "model for region\"},{\"title\":\"Islamic State kills 85 more members "
+        "of Iraqi tribe\"},{\"title\":\"Iraqi officials:IS extremists line "
+        "up, kill 50\"},{\"title\":\"Burkina Faso army backs presidential "
+        "guard official to lead transition\"},{\"title\":\"Kurdish peshmerga "
+        "arrive with weapons in Syria's Kobani\"},{\"title\":\"Driver sought "
+        "in crash that killed 3 on Halloween\"},{\"title\":\"Ex-Marine arrives "
+        "in US after release from Mexico jail\"},{\"title\":\"UN panel "
+        "scrambling to finish climate report\"},{\"title\":\"Investigators, "
+        "Branson go to spacecraft crash site\"},{\"title\":\"Soldiers vie for "
+        "power after Burkina Faso president quits\"},{\"title\":\"For a man "
+        "without a party, turnout is big test\"},{\"title\":\"'We just had a "
+        "hunch':US marshals nab Eric Frein\"},{\"title\":\"Boko Haram leader "
+        "threatens to kill German hostage\"},{\"title\":\"Nurse free to move "
+        "about as restrictions eased\"},{\"title\":\"Former Burkina president "
+        "Compaore arrives in Ivory Coast:sources\"},{\"title\":\"Libyan port "
+        "rebel leader refuses to hand over oil ports to rival "
+        "group\"},{\"title\":\"Iraqi peshmerga fighters prepare for Syria "
+        "battle\"},{\"title\":\"1 Dem Senate candidate welcoming Obama's "
+        "help\"},{\"title\":\"Bikers cancel party after police recover "
+        "bar\"},{\"title\":\"New question in Texas:Can Davis survive "
+        "defeat?\"},{\"title\":\"Ukraine rebels to hold election, despite "
+        "criticism\"},{\"title\":\"Iraqi officials say Islamic State group "
+        "lines up, kills 50 tribesmen, women in Anbar "
+        "province\"},{\"title\":\"James rebounds, leads Cavaliers past "
+        "Bulls\"},{\"title\":\"UK warns travelers they could be terror "
+        "targets\"},{\"title\":\"Hello Kitty celebrates 40th "
+        "birthday\"},{\"title\":\"A look at people killed during space "
+        "missions\"},{\"title\":\"Nigeria's purported Boko Haram leader says "
+        "has 'married off' girls:AFP\"},{\"title\":\"Mexico orders immediate "
+        "release of Marine veteran\"},{\"title\":\"As election closes in, "
+        "Obama on center stage\"},{\"title\":\"Body of Zambian president "
+        "arrives home\"},{\"title\":\"South Africa arrests 2 Vietnamese for "
+        "poaching\"}]}}}");
+  }
+}

extras/tests/JsonArray/CMakeLists.txt

@@ -0,0 +1,23 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(JsonArrayTests 
+	add.cpp
+	copyArray.cpp
+	createNested.cpp
+	equals.cpp
+	get.cpp
+	isNull.cpp
+	iterator.cpp
+	memoryUsage.cpp
+	nesting.cpp
+	remove.cpp
+	size.cpp
+	std_string.cpp
+	subscript.cpp
+	undefined.cpp
+)
+
+target_link_libraries(JsonArrayTests catch)
+add_test(JsonArray JsonArrayTests)

extras/tests/JsonArray/add.cpp

@@ -0,0 +1,138 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::add()") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+
+  SECTION("int") {
+    array.add(123);
+    REQUIRE(123 == array[0].as<int>());
+    REQUIRE(array[0].is<int>());
+    REQUIRE(array[0].is<double>());
+  }
+
+  SECTION("double") {
+    array.add(123.45);
+    REQUIRE(123.45 == array[0].as<double>());
+    REQUIRE(array[0].is<double>());
+    REQUIRE_FALSE(array[0].is<bool>());
+  }
+
+  SECTION("bool") {
+    array.add(true);
+    REQUIRE(true == array[0].as<bool>());
+    REQUIRE(array[0].is<bool>());
+    REQUIRE_FALSE(array[0].is<int>());
+  }
+
+  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>());
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("vla") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "world");
+
+    array.add(vla);
+
+    REQUIRE(std::string("world") == array[0]);
+  }
+#endif
+
+  SECTION("nested array") {
+    DynamicJsonDocument doc2(4096);
+    JsonArray arr = doc2.to<JsonArray>();
+
+    array.add(arr);
+
+    REQUIRE(arr == array[0].as<JsonArray>());
+    REQUIRE(array[0].is<JsonArray>());
+    REQUIRE_FALSE(array[0].is<int>());
+  }
+
+  SECTION("nested object") {
+    DynamicJsonDocument doc2(4096);
+    JsonObject obj = doc2.to<JsonObject>();
+
+    array.add(obj);
+
+    REQUIRE(obj == array[0].as<JsonObject>());
+    REQUIRE(array[0].is<JsonObject>());
+    REQUIRE_FALSE(array[0].is<int>());
+  }
+
+  SECTION("array subscript") {
+    const char* str = "hello";
+    DynamicJsonDocument doc2(4096);
+    JsonArray arr = doc2.to<JsonArray>();
+    arr.add(str);
+
+    array.add(arr[0]);
+
+    REQUIRE(str == array[0]);
+  }
+
+  SECTION("object subscript") {
+    const char* str = "hello";
+    DynamicJsonDocument doc2(4096);
+    JsonObject obj = doc2.to<JsonObject>();
+    obj["x"] = str;
+
+    array.add(obj["x"]);
+
+    REQUIRE(str == array[0]);
+  }
+
+  SECTION("should not duplicate const char*") {
+    array.add("world");
+    const size_t expectedSize = JSON_ARRAY_SIZE(1);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate char*") {
+    array.add(const_cast<char*>("world"));
+    const size_t expectedSize = JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate std::string") {
+    array.add(std::string("world"));
+    const size_t expectedSize = JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should not duplicate serialized(const char*)") {
+    array.add(serialized("{}"));
+    const size_t expectedSize = JSON_ARRAY_SIZE(1);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate serialized(char*)") {
+    array.add(serialized(const_cast<char*>("{}")));
+    const size_t expectedSize = JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(2);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate serialized(std::string)") {
+    array.add(serialized(std::string("{}")));
+    const size_t expectedSize = JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(2);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate serialized(std::string)") {
+    array.add(serialized(std::string("\0XX", 3)));
+    const size_t expectedSize = JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(3);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+}

extras/tests/JsonArray/copyArray.cpp

@@ -0,0 +1,117 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("copyArray()") {
+  SECTION("1D -> JsonArray") {
+    DynamicJsonDocument doc(4096);
+    JsonArray array = doc.to<JsonArray>();
+    char json[32];
+    int source[] = {1, 2, 3};
+
+    bool ok = copyArray(source, array);
+    REQUIRE(ok);
+
+    serializeJson(array, json, sizeof(json));
+    REQUIRE(std::string("[1,2,3]") == json);
+  }
+
+  SECTION("1D -> JsonArray, but not enough memory") {
+    const size_t SIZE = JSON_ARRAY_SIZE(2);
+    StaticJsonDocument<SIZE> doc;
+    JsonArray array = doc.to<JsonArray>();
+    char json[32];
+    int source[] = {1, 2, 3};
+
+    bool ok = copyArray(source, array);
+    REQUIRE_FALSE(ok);
+
+    serializeJson(array, json, sizeof(json));
+    REQUIRE(std::string("[1,2]") == json);
+  }
+
+  SECTION("2D -> JsonArray") {
+    DynamicJsonDocument doc(4096);
+    JsonArray array = doc.to<JsonArray>();
+    char json[32];
+    int source[][3] = {{1, 2, 3}, {4, 5, 6}};
+
+    bool ok = copyArray(source, array);
+    REQUIRE(ok);
+
+    serializeJson(array, json, sizeof(json));
+    REQUIRE(std::string("[[1,2,3],[4,5,6]]") == json);
+  }
+
+  SECTION("2D -> JsonArray, but not enough memory") {
+    const size_t SIZE =
+        JSON_ARRAY_SIZE(2) + JSON_ARRAY_SIZE(3) + JSON_ARRAY_SIZE(2);
+    StaticJsonDocument<SIZE> doc;
+    JsonArray array = doc.to<JsonArray>();
+    char json[32] = "";
+    int source[][3] = {{1, 2, 3}, {4, 5, 6}};
+
+    CAPTURE(SIZE)
+
+    bool ok = copyArray(source, array);
+    CAPTURE(doc.memoryUsage());
+    CHECK_FALSE(ok);
+
+    serializeJson(array, json, sizeof(json));
+    REQUIRE(std::string("[[1,2,3],[4,5]]") == json);
+  }
+
+  SECTION("JsonArray -> 1D, with more space than needed") {
+    DynamicJsonDocument doc(4096);
+    char json[] = "[1,2,3]";
+    DeserializationError err = deserializeJson(doc, json);
+    REQUIRE(err == DeserializationError::Ok);
+    JsonArray array = doc.as<JsonArray>();
+
+    int destination[4] = {0};
+    size_t result = copyArray(array, destination);
+
+    REQUIRE(3 == result);
+    REQUIRE(1 == destination[0]);
+    REQUIRE(2 == destination[1]);
+    REQUIRE(3 == destination[2]);
+    REQUIRE(0 == destination[3]);
+  }
+
+  SECTION("JsonArray -> 1D, without enough space") {
+    DynamicJsonDocument doc(4096);
+    char json[] = "[1,2,3]";
+    DeserializationError err = deserializeJson(doc, json);
+    REQUIRE(err == DeserializationError::Ok);
+    JsonArray array = doc.as<JsonArray>();
+
+    int destination[2] = {0};
+    size_t result = copyArray(array, destination);
+
+    REQUIRE(2 == result);
+    REQUIRE(1 == destination[0]);
+    REQUIRE(2 == destination[1]);
+  }
+
+  SECTION("JsonArray -> 2D") {
+    DynamicJsonDocument doc(4096);
+    char json[] = "[[1,2],[3],[4]]";
+
+    DeserializationError err = deserializeJson(doc, json);
+    REQUIRE(err == DeserializationError::Ok);
+    JsonArray array = doc.as<JsonArray>();
+
+    int destination[3][2] = {{0}};
+    copyArray(array, destination);
+
+    REQUIRE(1 == destination[0][0]);
+    REQUIRE(2 == destination[0][1]);
+    REQUIRE(3 == destination[1][0]);
+    REQUIRE(0 == destination[1][1]);
+    REQUIRE(4 == destination[2][0]);
+    REQUIRE(0 == destination[2][1]);
+  }
+}

extras/tests/JsonArray/createNested.cpp

@@ -0,0 +1,21 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray basics") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+
+  SECTION("CreateNestedArray") {
+    JsonArray arr = array.createNestedArray();
+    REQUIRE(arr == array[0].as<JsonArray>());
+  }
+
+  SECTION("CreateNestedObject") {
+    JsonObject obj = array.createNestedObject();
+    REQUIRE(obj == array[0].as<JsonObject>());
+  }
+}

extras/tests/JsonArray/equals.cpp

@@ -0,0 +1,50 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::operator==()") {
+  DynamicJsonDocument doc1(4096);
+  JsonArray array1 = doc1.to<JsonArray>();
+  JsonArrayConst array1c = array1;
+
+  DynamicJsonDocument doc2(4096);
+  JsonArray array2 = doc2.to<JsonArray>();
+  JsonArrayConst array2c = array2;
+
+  SECTION("should return false when arrays differ") {
+    array1.add("coucou");
+    array2.add(1);
+
+    REQUIRE_FALSE(array1 == array2);
+    REQUIRE_FALSE(array1c == array2c);
+  }
+
+  SECTION("should return false when LHS has more elements") {
+    array1.add(1);
+    array1.add(2);
+    array2.add(1);
+
+    REQUIRE_FALSE(array1 == array2);
+    REQUIRE_FALSE(array1c == array2c);
+  }
+
+  SECTION("should return false when RKS has more elements") {
+    array1.add(1);
+    array2.add(1);
+    array2.add(2);
+
+    REQUIRE_FALSE(array1 == array2);
+    REQUIRE_FALSE(array1c == array2c);
+  }
+
+  SECTION("should return true when arrays equal") {
+    array1.add("coucou");
+    array2.add("coucou");
+
+    REQUIRE(array1 == array2);
+    REQUIRE(array1c == array2c);
+  }
+}

extras/tests/JsonArray/get.cpp

@@ -0,0 +1,16 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::get()") {
+  DynamicJsonDocument doc(4096);
+  deserializeJson(doc, "[1,2,3]");
+  JsonArray array = doc.as<JsonArray>();
+
+  SECTION("Overflow") {
+    REQUIRE(array.getElement(3).isNull());
+  }
+}

extras/tests/JsonArray/isNull.cpp

@@ -0,0 +1,34 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::isNull()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("returns true") {
+    JsonArray arr;
+    REQUIRE(arr.isNull() == true);
+  }
+
+  SECTION("returns false") {
+    JsonArray arr = doc.to<JsonArray>();
+    REQUIRE(arr.isNull() == false);
+  }
+}
+
+TEST_CASE("JsonArrayConst::isNull()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("returns true") {
+    JsonArrayConst arr;
+    REQUIRE(arr.isNull() == true);
+  }
+
+  SECTION("returns false") {
+    JsonArrayConst arr = doc.to<JsonArray>();
+    REQUIRE(arr.isNull() == false);
+  }
+}

extras/tests/JsonArray/iterator.cpp

@@ -0,0 +1,36 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+template <typename TArray>
+static void run_iterator_test() {
+  StaticJsonDocument<JSON_ARRAY_SIZE(2)> doc;
+  JsonArray tmp = doc.to<JsonArray>();
+  tmp.add(12);
+  tmp.add(34);
+
+  TArray array = tmp;
+  typename TArray::iterator it = array.begin();
+  typename TArray::iterator end = array.end();
+
+  REQUIRE(end != it);
+  REQUIRE(12 == it->template as<int>());
+  REQUIRE(12 == static_cast<int>(*it));
+  ++it;
+  REQUIRE(end != it);
+  REQUIRE(34 == it->template as<int>());
+  REQUIRE(34 == static_cast<int>(*it));
+  ++it;
+  REQUIRE(end == it);
+}
+
+TEST_CASE("JsonArray::begin()/end()") {
+  run_iterator_test<JsonArray>();
+}
+
+TEST_CASE("JsonArrayConst::begin()/end()") {
+  run_iterator_test<JsonArrayConst>();
+}

extras/tests/JsonArray/memoryUsage.cpp

@@ -0,0 +1,42 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::memoryUsage()") {
+  DynamicJsonDocument doc(4096);
+  JsonArray arr = doc.to<JsonArray>();
+
+  SECTION("return 0 if uninitialized") {
+    JsonArray unitialized;
+    REQUIRE(unitialized.memoryUsage() == 0);
+  }
+
+  SECTION("JSON_ARRAY_SIZE(0) if empty") {
+    REQUIRE(arr.memoryUsage() == JSON_ARRAY_SIZE(0));
+  }
+
+  SECTION("JSON_ARRAY_SIZE(1) after add") {
+    arr.add("hello");
+    REQUIRE(arr.memoryUsage() == JSON_ARRAY_SIZE(1));
+  }
+
+  SECTION("includes the size of the string") {
+    arr.add(std::string("hello"));
+    REQUIRE(arr.memoryUsage() == JSON_ARRAY_SIZE(1) + 6);
+  }
+
+  SECTION("includes the size of the nested array") {
+    JsonArray nested = arr.createNestedArray();
+    nested.add(42);
+    REQUIRE(arr.memoryUsage() == 2 * JSON_ARRAY_SIZE(1));
+  }
+
+  SECTION("includes the size of the nested arrect") {
+    JsonObject nested = arr.createNestedObject();
+    nested["hello"] = "world";
+    REQUIRE(arr.memoryUsage() == JSON_OBJECT_SIZE(1) + JSON_ARRAY_SIZE(1));
+  }
+}

extras/tests/JsonArray/nesting.cpp

@@ -0,0 +1,35 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::nesting()") {
+  DynamicJsonDocument doc(4096);
+  JsonArray arr = doc.to<JsonArray>();
+
+  SECTION("return 0 if uninitialized") {
+    JsonArray unitialized;
+    REQUIRE(unitialized.nesting() == 0);
+  }
+
+  SECTION("returns 1 for empty array") {
+    REQUIRE(arr.nesting() == 1);
+  }
+
+  SECTION("returns 1 for flat array") {
+    arr.add("hello");
+    REQUIRE(arr.nesting() == 1);
+  }
+
+  SECTION("returns 2 with nested array") {
+    arr.createNestedArray();
+    REQUIRE(arr.nesting() == 2);
+  }
+
+  SECTION("returns 2 with nested object") {
+    arr.createNestedObject();
+    REQUIRE(arr.nesting() == 2);
+  }
+}

extras/tests/JsonArray/remove.cpp

@@ -0,0 +1,68 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::remove()") {
+  DynamicJsonDocument doc(4096);
+  JsonArray _array = doc.to<JsonArray>();
+  _array.add(1);
+  _array.add(2);
+  _array.add(3);
+
+  SECTION("RemoveFirstByIndex") {
+    _array.remove(0);
+
+    REQUIRE(2 == _array.size());
+    REQUIRE(_array[0] == 2);
+    REQUIRE(_array[1] == 3);
+  }
+
+  SECTION("RemoveMiddleByIndex") {
+    _array.remove(1);
+
+    REQUIRE(2 == _array.size());
+    REQUIRE(_array[0] == 1);
+    REQUIRE(_array[1] == 3);
+  }
+
+  SECTION("RemoveLastByIndex") {
+    _array.remove(2);
+
+    REQUIRE(2 == _array.size());
+    REQUIRE(_array[0] == 1);
+    REQUIRE(_array[1] == 2);
+  }
+
+  SECTION("RemoveFirstByIterator") {
+    JsonArray::iterator it = _array.begin();
+    _array.remove(it);
+
+    REQUIRE(2 == _array.size());
+    REQUIRE(_array[0] == 2);
+    REQUIRE(_array[1] == 3);
+  }
+
+  SECTION("RemoveMiddleByIterator") {
+    JsonArray::iterator it = _array.begin();
+    ++it;
+    _array.remove(it);
+
+    REQUIRE(2 == _array.size());
+    REQUIRE(_array[0] == 1);
+    REQUIRE(_array[1] == 3);
+  }
+
+  SECTION("RemoveLastByIterator") {
+    JsonArray::iterator it = _array.begin();
+    ++it;
+    ++it;
+    _array.remove(it);
+
+    REQUIRE(2 == _array.size());
+    REQUIRE(_array[0] == 1);
+    REQUIRE(_array[1] == 2);
+  }
+}

extras/tests/JsonArray/size.cpp

@@ -0,0 +1,31 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::size()") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+
+  SECTION("returns 0 is empty") {
+    REQUIRE(0U == array.size());
+  }
+
+  SECTION("increases after add()") {
+    array.add("hello");
+    REQUIRE(1U == array.size());
+
+    array.add("world");
+    REQUIRE(2U == array.size());
+  }
+
+  SECTION("remains the same after replacing an element") {
+    array.add("hello");
+    REQUIRE(1U == array.size());
+
+    array[0] = "hello";
+    REQUIRE(1U == array.size());
+  }
+}

extras/tests/JsonArray/std_string.cpp

@@ -0,0 +1,31 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+static void eraseString(std::string &str) {
+  char *p = const_cast<char *>(str.c_str());
+  while (*p) *p++ = '*';
+}
+
+TEST_CASE("std::string") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+
+  SECTION("add()") {
+    std::string value("hello");
+    array.add(value);
+    eraseString(value);
+    REQUIRE(std::string("hello") == array[0]);
+  }
+
+  SECTION("operator[]") {
+    std::string value("world");
+    array.add("hello");
+    array[0] = value;
+    eraseString(value);
+    REQUIRE(std::string("world") == array[0]);
+  }
+}

extras/tests/JsonArray/subscript.cpp

@@ -0,0 +1,162 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonArray::operator[]") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+  array.add(0);
+
+  SECTION("int") {
+    array[0] = 123;
+    REQUIRE(123 == array[0].as<int>());
+    REQUIRE(true == array[0].is<int>());
+    REQUIRE(false == array[0].is<bool>());
+  }
+
+#if ARDUINOJSON_USE_LONG_LONG
+  SECTION("long long") {
+    array[0] = 9223372036854775807;
+    REQUIRE(9223372036854775807 == array[0].as<int64_t>());
+    REQUIRE(true == array[0].is<int64_t>());
+    REQUIRE(false == array[0].is<int32_t>());
+    REQUIRE(false == array[0].is<bool>());
+  }
+#endif
+
+  SECTION("double") {
+    array[0] = 123.45;
+    REQUIRE(123.45 == array[0].as<double>());
+    REQUIRE(true == array[0].is<double>());
+    REQUIRE(false == array[0].is<int>());
+  }
+
+  SECTION("bool") {
+    array[0] = true;
+    REQUIRE(true == array[0].as<bool>());
+    REQUIRE(true == array[0].is<bool>());
+    REQUIRE(false == array[0].is<int>());
+  }
+
+  SECTION("const char*") {
+    const char* str = "hello";
+
+    array[0] = str;
+    REQUIRE(str == array[0].as<const char*>());
+    REQUIRE(str == array[0].as<char*>());  // <- short hand
+    REQUIRE(true == array[0].is<const char*>());
+    REQUIRE(false == array[0].is<int>());
+  }
+
+  SECTION("nested array") {
+    DynamicJsonDocument doc2(4096);
+    JsonArray arr2 = doc2.to<JsonArray>();
+
+    array[0] = arr2;
+
+    REQUIRE(arr2 == array[0].as<JsonArray>());
+    REQUIRE(true == array[0].is<JsonArray>());
+    REQUIRE(false == array[0].is<int>());
+  }
+
+  SECTION("nested object") {
+    DynamicJsonDocument doc2(4096);
+    JsonObject obj = doc2.to<JsonObject>();
+
+    array[0] = obj;
+
+    REQUIRE(obj == array[0].as<JsonObject>());
+    REQUIRE(true == array[0].is<JsonObject>());
+    REQUIRE(false == array[0].is<int>());
+  }
+
+  SECTION("array subscript") {
+    DynamicJsonDocument doc2(4096);
+    JsonArray arr2 = doc2.to<JsonArray>();
+    const char* str = "hello";
+
+    arr2.add(str);
+
+    array[0] = arr2[0];
+
+    REQUIRE(str == array[0]);
+  }
+
+  SECTION("object subscript") {
+    const char* str = "hello";
+    DynamicJsonDocument doc2(4096);
+    JsonObject obj = doc2.to<JsonObject>();
+
+    obj["x"] = str;
+
+    array[0] = obj["x"];
+
+    REQUIRE(str == array[0]);
+  }
+
+  SECTION("should not duplicate const char*") {
+    array[0] = "world";
+    const size_t expectedSize = JSON_ARRAY_SIZE(1);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate char*") {
+    array[0] = const_cast<char*>("world");
+    const size_t expectedSize = JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate std::string") {
+    array[0] = std::string("world");
+    const size_t expectedSize = JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("array[0].to<JsonObject>()") {
+    JsonObject obj = array[0].to<JsonObject>();
+    REQUIRE(obj.isNull() == false);
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("set(VLA)") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "world");
+
+    array.add("hello");
+    array[0].set(vla);
+
+    REQUIRE(std::string("world") == array[0]);
+  }
+
+  SECTION("operator=(VLA)") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "world");
+
+    array.add("hello");
+    array[0] = vla;
+
+    REQUIRE(std::string("world") == array[0]);
+  }
+#endif
+}
+
+TEST_CASE("JsonArrayConst::operator[]") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+  array.add(0);
+
+  SECTION("int") {
+    array[0] = 123;
+    JsonArrayConst carr = array;
+
+    REQUIRE(123 == carr[0].as<int>());
+    REQUIRE(true == carr[0].is<int>());
+    REQUIRE(false == carr[0].is<bool>());
+  }
+}

extras/tests/JsonArray/undefined.cpp

@@ -0,0 +1,35 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace Catch::Matchers;
+
+TEST_CASE("Undefined JsonArray") {
+  JsonArray array;
+
+  SECTION("SubscriptFails") {
+    REQUIRE(array[0].isNull());
+  }
+
+  SECTION("AddFails") {
+    array.add(1);
+    REQUIRE(0 == array.size());
+  }
+
+  SECTION("CreateNestedArrayFails") {
+    REQUIRE(array.createNestedArray().isNull());
+  }
+
+  SECTION("CreateNestedObjectFails") {
+    REQUIRE(array.createNestedObject().isNull());
+  }
+
+  SECTION("PrintToWritesBrackets") {
+    char buffer[32];
+    serializeJson(array, buffer, sizeof(buffer));
+    REQUIRE_THAT(buffer, Equals("null"));
+  }
+}

extras/tests/JsonDeserializer/CMakeLists.txt

@@ -0,0 +1,21 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(JsonDeserializerTests
+	array.cpp
+	array_static.cpp
+	DeserializationError.cpp
+	incomplete_input.cpp
+	input_types.cpp
+	number.cpp
+	invalid_input.cpp
+	misc.cpp
+	nestingLimit.cpp
+	object.cpp
+	object_static.cpp
+	string.cpp
+)
+
+target_link_libraries(JsonDeserializerTests catch)
+add_test(JsonDeserializer JsonDeserializerTests)

extras/tests/JsonDeserializer/DeserializationError.cpp

@@ -0,0 +1,137 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+void testStringification(DeserializationError error, std::string expected) {
+  REQUIRE(error.c_str() == expected);
+}
+
+void testBoolification(DeserializationError error, bool expected) {
+  // DeserializationError on left-hand side
+  CHECK(error == expected);
+  CHECK(error != !expected);
+  CHECK(!error == !expected);
+
+  // DeserializationError on right-hand side
+  CHECK(expected == error);
+  CHECK(!expected != error);
+  CHECK(!expected == !error);
+}
+
+#define TEST_STRINGIFICATION(symbol) \
+  testStringification(DeserializationError::symbol, #symbol)
+
+#define TEST_BOOLIFICATION(symbol, expected) \
+  testBoolification(DeserializationError::symbol, expected)
+
+TEST_CASE("DeserializationError") {
+  SECTION("c_str()") {
+    TEST_STRINGIFICATION(Ok);
+    TEST_STRINGIFICATION(TooDeep);
+    TEST_STRINGIFICATION(NoMemory);
+    TEST_STRINGIFICATION(InvalidInput);
+    TEST_STRINGIFICATION(IncompleteInput);
+    TEST_STRINGIFICATION(NotSupported);
+  }
+
+  SECTION("as boolean") {
+    TEST_BOOLIFICATION(Ok, false);
+    TEST_BOOLIFICATION(TooDeep, true);
+    TEST_BOOLIFICATION(NoMemory, true);
+    TEST_BOOLIFICATION(InvalidInput, true);
+    TEST_BOOLIFICATION(IncompleteInput, true);
+    TEST_BOOLIFICATION(NotSupported, true);
+  }
+
+  SECTION("ostream DeserializationError") {
+    std::stringstream s;
+    s << DeserializationError(DeserializationError::InvalidInput);
+    REQUIRE(s.str() == "InvalidInput");
+  }
+
+  SECTION("ostream DeserializationError::Code") {
+    std::stringstream s;
+    s << DeserializationError::InvalidInput;
+    REQUIRE(s.str() == "InvalidInput");
+  }
+
+  SECTION("out of range") {
+    int code = 666;
+    DeserializationError err(
+        *reinterpret_cast<DeserializationError::Code*>(&code));
+    REQUIRE(err.c_str() == std::string("???"));
+  }
+
+  SECTION("switch") {
+    DeserializationError err = DeserializationError::InvalidInput;
+    switch (err.code()) {
+      case DeserializationError::InvalidInput:
+        SUCCEED();
+        break;
+      default:
+        FAIL();
+        break;
+    }
+  }
+
+  SECTION("Comparisons") {
+    DeserializationError invalidInput(DeserializationError::InvalidInput);
+    DeserializationError ok(DeserializationError::Ok);
+
+    SECTION("DeserializationError == bool") {
+      REQUIRE(invalidInput == true);
+      REQUIRE(ok == false);
+    }
+
+    SECTION("bool == DeserializationError") {
+      REQUIRE(true == invalidInput);
+      REQUIRE(false == ok);
+    }
+
+    SECTION("DeserializationError != bool") {
+      REQUIRE(invalidInput != false);
+      REQUIRE(ok != true);
+    }
+
+    SECTION("bool != DeserializationError") {
+      REQUIRE(false != invalidInput);
+      REQUIRE(true != ok);
+    }
+
+    SECTION("Negations") {
+      REQUIRE(!invalidInput == false);
+      REQUIRE(!ok == true);
+    }
+
+    SECTION("DeserializationError == Code") {
+      REQUIRE(invalidInput == DeserializationError::InvalidInput);
+      REQUIRE(ok == DeserializationError::Ok);
+    }
+
+    SECTION("Code == DeserializationError") {
+      REQUIRE(DeserializationError::InvalidInput == invalidInput);
+      REQUIRE(DeserializationError::Ok == ok);
+    }
+
+    SECTION("DeserializationError != Code") {
+      REQUIRE(invalidInput != DeserializationError::Ok);
+      REQUIRE(ok != DeserializationError::InvalidInput);
+    }
+
+    SECTION("Code != DeserializationError") {
+      REQUIRE(DeserializationError::Ok != invalidInput);
+      REQUIRE(DeserializationError::InvalidInput != ok);
+    }
+
+    SECTION("DeserializationError == DeserializationError") {
+      REQUIRE_FALSE(invalidInput == ok);
+    }
+
+    SECTION("DeserializationError != DeserializationError") {
+      REQUIRE(invalidInput != ok);
+    }
+  }
+}

extras/tests/JsonDeserializer/array.cpp

@@ -0,0 +1,402 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("deserialize JSON array") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("An empty array") {
+    DeserializationError err = deserializeJson(doc, "[]");
+    JsonArray arr = doc.as<JsonArray>();
+
+    REQUIRE(err == DeserializationError::Ok);
+    REQUIRE(0 == arr.size());
+  }
+
+  SECTION("Spaces") {
+    SECTION("Before the opening bracket") {
+      DeserializationError err = deserializeJson(doc, "  []");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(0 == arr.size());
+    }
+
+    SECTION("Before first value") {
+      DeserializationError err = deserializeJson(doc, "[ \t\r\n42]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == 42);
+    }
+
+    SECTION("After first value") {
+      DeserializationError err = deserializeJson(doc, "[42 \t\r\n]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == 42);
+    }
+  }
+
+  SECTION("Values types") {
+    SECTION("On integer") {
+      DeserializationError err = deserializeJson(doc, "[42]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == 42);
+    }
+
+    SECTION("Two integers") {
+      DeserializationError err = deserializeJson(doc, "[42,84]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == 42);
+      REQUIRE(arr[1] == 84);
+    }
+
+    SECTION("Double") {
+      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);
+    }
+
+    SECTION("Unsigned long") {
+      DeserializationError err = deserializeJson(doc, "[4294967295]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == 4294967295UL);
+    }
+
+    SECTION("Boolean") {
+      DeserializationError err = deserializeJson(doc, "[true,false]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == true);
+      REQUIRE(arr[1] == false);
+    }
+
+    SECTION("Null") {
+      DeserializationError err = deserializeJson(doc, "[null,null]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0].as<char*>() == 0);
+      REQUIRE(arr[1].as<char*>() == 0);
+    }
+  }
+
+  SECTION("Quotes") {
+    SECTION("Double quotes") {
+      DeserializationError err =
+          deserializeJson(doc, "[ \"hello\" , \"world\" ]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "hello");
+      REQUIRE(arr[1] == "world");
+    }
+
+    SECTION("Single quotes") {
+      DeserializationError err = deserializeJson(doc, "[ 'hello' , 'world' ]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "hello");
+      REQUIRE(arr[1] == "world");
+    }
+
+    SECTION("No quotes") {
+      DeserializationError err = deserializeJson(doc, "[ hello , world ]");
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("Double quotes (empty strings)") {
+      DeserializationError err = deserializeJson(doc, "[\"\",\"\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "");
+      REQUIRE(arr[1] == "");
+    }
+
+    SECTION("Single quotes (empty strings)") {
+      DeserializationError err = deserializeJson(doc, "[\'\',\'\']");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "");
+      REQUIRE(arr[1] == "");
+    }
+
+    SECTION("No quotes (empty strings)") {
+      DeserializationError err = deserializeJson(doc, "[,]");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("Closing single quotes missing") {
+      DeserializationError err = deserializeJson(doc, "[\"]");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("Closing double quotes missing") {
+      DeserializationError err = deserializeJson(doc, "[\']");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Block comments") {
+    SECTION("Before opening bracket") {
+      DeserializationError err =
+          deserializeJson(doc, "/*COMMENT*/  [\"hello\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("After opening bracket") {
+      DeserializationError err =
+          deserializeJson(doc, "[/*COMMENT*/ \"hello\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("Before closing bracket") {
+      DeserializationError err = deserializeJson(doc, "[\"hello\"/*COMMENT*/]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("After closing bracket") {
+      DeserializationError err = deserializeJson(doc, "[\"hello\"]/*COMMENT*/");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("Before comma") {
+      DeserializationError err =
+          deserializeJson(doc, "[\"hello\"/*COMMENT*/,\"world\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "hello");
+      REQUIRE(arr[1] == "world");
+    }
+
+    SECTION("After comma") {
+      DeserializationError err =
+          deserializeJson(doc, "[\"hello\",/*COMMENT*/ \"world\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "hello");
+      REQUIRE(arr[1] == "world");
+    }
+
+    SECTION("/*/") {
+      DeserializationError err = deserializeJson(doc, "[/*/\n]");
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("Unfinished comment") {
+      DeserializationError err = deserializeJson(doc, "[/*COMMENT]");
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("Final slash missing") {
+      DeserializationError err = deserializeJson(doc, "[/*COMMENT*]");
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Trailing comments") {
+    SECTION("Before opening bracket") {
+      DeserializationError err =
+          deserializeJson(doc, "//COMMENT\n\t[\"hello\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("After opening bracket") {
+      DeserializationError err = deserializeJson(doc, "[//COMMENT\n\"hello\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("Before closing bracket") {
+      DeserializationError err =
+          deserializeJson(doc, "[\"hello\"//COMMENT\r\n]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("After closing bracket") {
+      DeserializationError err = deserializeJson(doc, "[\"hello\"]//COMMENT\n");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(1 == arr.size());
+      REQUIRE(arr[0] == "hello");
+    }
+
+    SECTION("Before comma") {
+      DeserializationError err =
+          deserializeJson(doc, "[\"hello\"//COMMENT\n,\"world\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "hello");
+      REQUIRE(arr[1] == "world");
+    }
+
+    SECTION("After comma") {
+      DeserializationError err =
+          deserializeJson(doc, "[\"hello\",//COMMENT\n\"world\"]");
+      JsonArray arr = doc.as<JsonArray>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(2 == arr.size());
+      REQUIRE(arr[0] == "hello");
+      REQUIRE(arr[1] == "world");
+    }
+
+    SECTION("Invalid comment") {
+      DeserializationError err = deserializeJson(doc, "[/COMMENT\n]");
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("End document with comment") {
+      DeserializationError err = deserializeJson(doc, "[//COMMENT");
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Premature null-terminator") {
+    SECTION("After opening bracket") {
+      DeserializationError err = deserializeJson(doc, "[");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After value") {
+      DeserializationError err = deserializeJson(doc, "[1");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After comma") {
+      DeserializationError err = deserializeJson(doc, "[1,");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Premature end of input") {
+    const char* input = "[1,2]";
+
+    SECTION("After opening bracket") {
+      DeserializationError err = deserializeJson(doc, input, 1);
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After value") {
+      DeserializationError err = deserializeJson(doc, input, 2);
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After comma") {
+      DeserializationError err = deserializeJson(doc, input, 3);
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Misc") {
+    SECTION("Nested objects") {
+      char jsonString[] =
+          " [ { \"a\" : 1 , \"b\" : 2 } , { \"c\" : 3 , \"d\" : 4 } ] ";
+
+      DeserializationError err = deserializeJson(doc, jsonString);
+      JsonArray arr = doc.as<JsonArray>();
+
+      JsonObject object1 = arr[0];
+      const JsonObject object2 = arr[1];
+      JsonObject object3 = arr[2];
+
+      REQUIRE(err == DeserializationError::Ok);
+
+      REQUIRE(object1.isNull() == false);
+      REQUIRE(object2.isNull() == false);
+      REQUIRE(object3.isNull() == true);
+
+      REQUIRE(2 == object1.size());
+      REQUIRE(2 == object2.size());
+      REQUIRE(0 == object3.size());
+
+      REQUIRE(1 == object1["a"].as<int>());
+      REQUIRE(2 == object1["b"].as<int>());
+      REQUIRE(3 == object2["c"].as<int>());
+      REQUIRE(4 == object2["d"].as<int>());
+      REQUIRE(0 == object3["e"].as<int>());
+    }
+  }
+
+  SECTION("Should clear the JsonArray") {
+    deserializeJson(doc, "[1,2,3,4]");
+    deserializeJson(doc, "[]");
+    JsonArray arr = doc.as<JsonArray>();
+
+    REQUIRE(arr.size() == 0);
+    REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(0));
+  }
+}

extras/tests/JsonDeserializer/array_static.cpp

@@ -0,0 +1,89 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("deserialize JSON array with a StaticJsonDocument") {
+  SECTION("BufferOfTheRightSizeForEmptyArray") {
+    StaticJsonDocument<JSON_ARRAY_SIZE(0)> doc;
+    char input[] = "[]";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("TooSmallBufferForArrayWithOneValue") {
+    StaticJsonDocument<JSON_ARRAY_SIZE(0)> doc;
+    char input[] = "[1]";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::NoMemory);
+  }
+
+  SECTION("BufferOfTheRightSizeForArrayWithOneValue") {
+    StaticJsonDocument<JSON_ARRAY_SIZE(1)> doc;
+    char input[] = "[1]";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("TooSmallBufferForArrayWithNestedObject") {
+    StaticJsonDocument<JSON_ARRAY_SIZE(0) + JSON_OBJECT_SIZE(0)> doc;
+    char input[] = "[{}]";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::NoMemory);
+  }
+
+  SECTION("BufferOfTheRightSizeForArrayWithNestedObject") {
+    StaticJsonDocument<JSON_ARRAY_SIZE(1) + JSON_OBJECT_SIZE(0)> doc;
+    char input[] = "[{}]";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("CopyStringNotSpaces") {
+    StaticJsonDocument<100> doc;
+
+    deserializeJson(doc, "  [ \"1234567\" ] ");
+
+    REQUIRE(JSON_ARRAY_SIZE(1) + JSON_STRING_SIZE(8) == doc.memoryUsage());
+    // note: we use a string of 8 bytes to be sure that the StaticMemoryPool
+    // will not insert bytes to enforce alignement
+  }
+
+  SECTION("Should clear the JsonArray") {
+    StaticJsonDocument<JSON_ARRAY_SIZE(4)> doc;
+    char input[] = "[1,2,3,4]";
+
+    deserializeJson(doc, input);
+    deserializeJson(doc, "[]");
+
+    JsonArray arr = doc.as<JsonArray>();
+    REQUIRE(arr.size() == 0);
+    REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(0));
+  }
+
+  SECTION("Array") {
+    StaticJsonDocument<JSON_ARRAY_SIZE(2)> doc;
+    char input[] = "[1,2]";
+
+    DeserializationError err = deserializeJson(doc, input);
+    JsonArray arr = doc.as<JsonArray>();
+
+    REQUIRE(err == DeserializationError::Ok);
+    REQUIRE(doc.is<JsonArray>());
+    REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(2));
+    REQUIRE(arr[0] == 1);
+    REQUIRE(arr[1] == 2);
+  }
+}

extras/tests/JsonDeserializer/incomplete_input.cpp

@@ -0,0 +1,27 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#define ARDUINOJSON_DECODE_UNICODE 1
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("Truncated JSON input") {
+  const char* testCases[] = {"\"hello", "\'hello", "'\\u", "'\\u00", "'\\u000",
+                             // false
+                             "f", "fa", "fal", "fals",
+                             // true
+                             "t", "tr", "tru",
+                             // null
+                             "n", "nu", "nul"};
+  const size_t testCount = sizeof(testCases) / sizeof(testCases[0]);
+
+  DynamicJsonDocument doc(4096);
+
+  for (size_t i = 0; i < testCount; i++) {
+    const char* input = testCases[i];
+    CAPTURE(input);
+    REQUIRE(deserializeJson(doc, input) ==
+            DeserializationError::IncompleteInput);
+  }
+}

extras/tests/JsonDeserializer/input_types.cpp

@@ -0,0 +1,115 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <sstream>
+
+TEST_CASE("deserializeJson(const std::string&)") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("should accept const string") {
+    const std::string input("[42]");
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("should accept temporary string") {
+    DeserializationError err = deserializeJson(doc, std::string("[42]"));
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("should duplicate content") {
+    std::string input("[\"hello\"]");
+
+    DeserializationError err = deserializeJson(doc, input);
+    input[2] = 'X';  // alter the string tomake sure we made a copy
+
+    JsonArray array = doc.as<JsonArray>();
+    REQUIRE(err == DeserializationError::Ok);
+    REQUIRE(std::string("hello") == array[0]);
+  }
+}
+
+TEST_CASE("deserializeJson(std::istream&)") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("array") {
+    std::istringstream json(" [ 42 /* comment */ ] ");
+
+    DeserializationError err = deserializeJson(doc, json);
+    JsonArray arr = doc.as<JsonArray>();
+
+    REQUIRE(err == DeserializationError::Ok);
+    REQUIRE(1 == arr.size());
+    REQUIRE(42 == arr[0]);
+  }
+
+  SECTION("object") {
+    std::istringstream json(" { hello : 'world' // comment\n }");
+
+    DeserializationError err = deserializeJson(doc, json);
+    JsonObject obj = doc.as<JsonObject>();
+
+    REQUIRE(err == DeserializationError::Ok);
+    REQUIRE(1 == obj.size());
+    REQUIRE(std::string("world") == obj["hello"]);
+  }
+
+  SECTION("Should not read after the closing brace of an empty object") {
+    std::istringstream json("{}123");
+
+    deserializeJson(doc, json);
+
+    REQUIRE('1' == char(json.get()));
+  }
+
+  SECTION("Should not read after the closing brace") {
+    std::istringstream json("{\"hello\":\"world\"}123");
+
+    deserializeJson(doc, json);
+
+    REQUIRE('1' == char(json.get()));
+  }
+
+  SECTION("Should not read after the closing bracket of an empty array") {
+    std::istringstream json("[]123");
+
+    deserializeJson(doc, json);
+
+    REQUIRE('1' == char(json.get()));
+  }
+
+  SECTION("Should not read after the closing bracket") {
+    std::istringstream json("[\"hello\",\"world\"]123");
+
+    deserializeJson(doc, json);
+
+    REQUIRE('1' == char(json.get()));
+  }
+
+  SECTION("Should not read after the closing quote") {
+    std::istringstream json("\"hello\"123");
+
+    deserializeJson(doc, json);
+
+    REQUIRE('1' == char(json.get()));
+  }
+}
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+TEST_CASE("deserializeJson(VLA)") {
+  int i = 9;
+  char vla[i];
+  strcpy(vla, "{\"a\":42}");
+
+  StaticJsonDocument<JSON_OBJECT_SIZE(1)> doc;
+  DeserializationError err = deserializeJson(doc, vla);
+
+  REQUIRE(err == DeserializationError::Ok);
+}
+#endif

extras/tests/JsonDeserializer/invalid_input.cpp

@@ -0,0 +1,35 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#define ARDUINOJSON_DECODE_UNICODE 1
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("Invalid JSON input") {
+  const char* testCases[] = {"'\\u'",     "'\\u000g'", "'\\u000'", "'\\u000G'",
+                             "'\\u000/'", "\\x1234",   "6a9",      "1,",
+                             "2]",        "3}"};
+  const size_t testCount = sizeof(testCases) / sizeof(testCases[0]);
+
+  DynamicJsonDocument doc(4096);
+
+  for (size_t i = 0; i < testCount; i++) {
+    const char* input = testCases[i];
+    CAPTURE(input);
+    REQUIRE(deserializeJson(doc, input) == DeserializationError::InvalidInput);
+  }
+}
+
+TEST_CASE("Invalid JSON input that should pass") {
+  const char* testCases[] = {"nulL", "tru3", "fals3"};
+  const size_t testCount = sizeof(testCases) / sizeof(testCases[0]);
+
+  DynamicJsonDocument doc(4096);
+
+  for (size_t i = 0; i < testCount; i++) {
+    const char* input = testCases[i];
+    CAPTURE(input);
+    REQUIRE(deserializeJson(doc, input) == DeserializationError::Ok);
+  }
+}

extras/tests/JsonDeserializer/misc.cpp

@@ -0,0 +1,143 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace Catch::Matchers;
+
+TEST_CASE("deserializeJson(DynamicJsonDocument&)") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("Edge cases") {
+    SECTION("null char*") {
+      DeserializationError err = deserializeJson(doc, static_cast<char*>(0));
+
+      REQUIRE(err != DeserializationError::Ok);
+    }
+
+    SECTION("null const char*") {
+      DeserializationError err =
+          deserializeJson(doc, static_cast<const char*>(0));
+
+      REQUIRE(err != DeserializationError::Ok);
+    }
+
+    SECTION("Empty input") {
+      DeserializationError err = deserializeJson(doc, "");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("issue #628") {
+      DeserializationError err = deserializeJson(doc, "null");
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<float>() == false);
+    }
+
+    SECTION("Garbage") {
+      DeserializationError err = deserializeJson(doc, "%*$£¤");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+  }
+
+  SECTION("Booleans") {
+    SECTION("True") {
+      DeserializationError err = deserializeJson(doc, "true");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<bool>());
+      REQUIRE(doc.as<bool>() == true);
+    }
+
+    SECTION("False") {
+      DeserializationError err = deserializeJson(doc, "false");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<bool>());
+      REQUIRE(doc.as<bool>() == false);
+    }
+  }
+
+  SECTION("Comments") {
+    SECTION("Just a trailing comment") {
+      DeserializationError err = deserializeJson(doc, "// comment");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("Just a block comment") {
+      DeserializationError err = deserializeJson(doc, "/*comment*/");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("Just a slash") {
+      DeserializationError err = deserializeJson(doc, "/");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+  }
+
+  SECTION("Premature null-terminator") {
+    SECTION("In escape sequence") {
+      DeserializationError err = deserializeJson(doc, "\"\\");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("In block comment") {
+      DeserializationError err = deserializeJson(doc, "/* comment");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("In double quoted string") {
+      DeserializationError err = deserializeJson(doc, "\"hello");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("In single quoted string") {
+      DeserializationError err = deserializeJson(doc, "'hello");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Premature end of input") {
+    SECTION("In escape sequence") {
+      DeserializationError err = deserializeJson(doc, "\"\\n\"", 2);
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("In block comment") {
+      DeserializationError err = deserializeJson(doc, "/* comment */", 10);
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("In double quoted string") {
+      DeserializationError err = deserializeJson(doc, "\"hello\"", 6);
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("In single quoted string") {
+      DeserializationError err = deserializeJson(doc, "'hello'", 6);
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Should clear the JsonVariant") {
+    deserializeJson(doc, "[1,2,3]");
+    deserializeJson(doc, "{}");
+
+    REQUIRE(doc.is<JsonObject>());
+    REQUIRE(doc.memoryUsage() == JSON_OBJECT_SIZE(0));
+  }
+}

extras/tests/JsonDeserializer/nestingLimit.cpp

@@ -0,0 +1,101 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+#define SHOULD_WORK(expression) REQUIRE(DeserializationError::Ok == expression);
+#define SHOULD_FAIL(expression) \
+  REQUIRE(DeserializationError::TooDeep == expression);
+
+TEST_CASE("JsonDeserializer nesting") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("Input = const char*") {
+    SECTION("limit = 0") {
+      DeserializationOption::NestingLimit nesting(0);
+      SHOULD_WORK(deserializeJson(doc, "\"toto\"", nesting));
+      SHOULD_WORK(deserializeJson(doc, "123", nesting));
+      SHOULD_WORK(deserializeJson(doc, "true", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[]", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{}", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[\"toto\"]", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":1}", nesting));
+    }
+
+    SECTION("limit = 1") {
+      DeserializationOption::NestingLimit nesting(1);
+      SHOULD_WORK(deserializeJson(doc, "[\"toto\"]", nesting));
+      SHOULD_WORK(deserializeJson(doc, "{\"toto\":1}", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":{}}", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":[]}", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[[\"toto\"]]", nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[{\"toto\":1}]", nesting));
+    }
+  }
+
+  SECTION("char* and size_t") {
+    SECTION("limit = 0") {
+      DeserializationOption::NestingLimit nesting(0);
+      SHOULD_WORK(deserializeJson(doc, "\"toto\"", 6, nesting));
+      SHOULD_WORK(deserializeJson(doc, "123", 3, nesting));
+      SHOULD_WORK(deserializeJson(doc, "true", 4, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[]", 2, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{}", 2, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[\"toto\"]", 8, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":1}", 10, nesting));
+    }
+
+    SECTION("limit = 1") {
+      DeserializationOption::NestingLimit nesting(1);
+      SHOULD_WORK(deserializeJson(doc, "[\"toto\"]", 8, nesting));
+      SHOULD_WORK(deserializeJson(doc, "{\"toto\":1}", 10, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":{}}", 11, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":[]}", 11, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[[\"toto\"]]", 10, nesting));
+      SHOULD_FAIL(deserializeJson(doc, "[{\"toto\":1}]", 12, nesting));
+    }
+  }
+
+  SECTION("Input = std::string") {
+    SECTION("limit = 0") {
+      DeserializationOption::NestingLimit nesting(0);
+      SHOULD_WORK(deserializeJson(doc, std::string("\"toto\""), nesting));
+      SHOULD_WORK(deserializeJson(doc, std::string("123"), nesting));
+      SHOULD_WORK(deserializeJson(doc, std::string("true"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("[]"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("{}"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("[\"toto\"]"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("{\"toto\":1}"), nesting));
+    }
+
+    SECTION("limit = 1") {
+      DeserializationOption::NestingLimit nesting(1);
+      SHOULD_WORK(deserializeJson(doc, std::string("[\"toto\"]"), nesting));
+      SHOULD_WORK(deserializeJson(doc, std::string("{\"toto\":1}"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("{\"toto\":{}}"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("{\"toto\":[]}"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("[[\"toto\"]]"), nesting));
+      SHOULD_FAIL(deserializeJson(doc, std::string("[{\"toto\":1}]"), nesting));
+    }
+  }
+
+  SECTION("Input = std::istream") {
+    SECTION("limit = 0") {
+      DeserializationOption::NestingLimit nesting(0);
+      std::istringstream good("true");
+      std::istringstream bad("[]");
+      SHOULD_WORK(deserializeJson(doc, good, nesting));
+      SHOULD_FAIL(deserializeJson(doc, bad, nesting));
+    }
+
+    SECTION("limit = 1") {
+      DeserializationOption::NestingLimit nesting(1);
+      std::istringstream good("[\"toto\"]");
+      std::istringstream bad("{\"toto\":{}}");
+      SHOULD_WORK(deserializeJson(doc, good, nesting));
+      SHOULD_FAIL(deserializeJson(doc, bad, nesting));
+    }
+  }
+}

extras/tests/JsonDeserializer/number.cpp

@@ -0,0 +1,133 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#define ARDUINOJSON_USE_LONG_LONG 0
+#define ARDUINOJSON_ENABLE_NAN 1
+#define ARDUINOJSON_ENABLE_INFINITY 1
+
+#include <ArduinoJson.h>
+#include <limits.h>
+#include <catch.hpp>
+
+namespace my {
+using ARDUINOJSON_NAMESPACE::isinf;
+using ARDUINOJSON_NAMESPACE::isnan;
+}  // namespace my
+
+TEST_CASE("deserialize an integer") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("Integer") {
+    SECTION("0") {
+      DeserializationError err = deserializeJson(doc, "0");
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<int>() == true);
+      REQUIRE(doc.as<int>() == 0);
+      REQUIRE(doc.as<std::string>() == "0");  // issue #808
+    }
+
+    SECTION("Negative") {
+      DeserializationError err = deserializeJson(doc, "-42");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<int>());
+      REQUIRE_FALSE(doc.is<bool>());
+      REQUIRE(doc.as<int>() == -42);
+    }
+
+#if LONG_MAX == 2147483647
+    SECTION("LONG_MAX") {
+      DeserializationError err = deserializeJson(doc, "2147483647");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<long>() == true);
+      REQUIRE(doc.as<long>() == LONG_MAX);
+    }
+
+    SECTION("LONG_MAX + 1") {
+      DeserializationError err = deserializeJson(doc, "2147483648");
+
+      CAPTURE(LONG_MIN);
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<long>() == false);
+      REQUIRE(doc.is<float>() == true);
+    }
+#endif
+
+#if LONG_MIN == -2147483648
+    SECTION("LONG_MIN") {
+      DeserializationError err = deserializeJson(doc, "-2147483648");
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<long>() == true);
+      REQUIRE(doc.as<long>() == LONG_MIN);
+    }
+
+    SECTION("LONG_MIN - 1") {
+      DeserializationError err = deserializeJson(doc, "-2147483649");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<long>() == false);
+      REQUIRE(doc.is<float>() == true);
+    }
+#endif
+
+#if ULONG_MAX == 4294967295
+    SECTION("ULONG_MAX") {
+      DeserializationError err = deserializeJson(doc, "4294967295");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<unsigned long>() == true);
+      REQUIRE(doc.as<unsigned long>() == ULONG_MAX);
+      REQUIRE(doc.is<long>() == false);
+    }
+
+    SECTION("ULONG_MAX + 1") {
+      DeserializationError err = deserializeJson(doc, "4294967296");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<unsigned long>() == false);
+      REQUIRE(doc.is<float>() == true);
+    }
+#endif
+  }
+
+  SECTION("Floats") {
+    SECTION("Double") {
+      DeserializationError err = deserializeJson(doc, "-1.23e+4");
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE_FALSE(doc.is<int>());
+      REQUIRE(doc.is<double>());
+      REQUIRE(doc.as<double>() == Approx(-1.23e+4));
+    }
+
+    SECTION("NaN") {
+      DeserializationError err = deserializeJson(doc, "NaN");
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<float>() == true);
+      REQUIRE(my::isnan(doc.as<float>()));
+    }
+
+    SECTION("Infinity") {
+      DeserializationError err = deserializeJson(doc, "Infinity");
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<float>() == true);
+      REQUIRE(my::isinf(doc.as<float>()));
+    }
+
+    SECTION("+Infinity") {
+      DeserializationError err = deserializeJson(doc, "+Infinity");
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<float>() == true);
+      REQUIRE(my::isinf(doc.as<float>()));
+    }
+
+    SECTION("-Infinity") {
+      DeserializationError err = deserializeJson(doc, "-Infinity");
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<float>() == true);
+      REQUIRE(my::isinf(doc.as<float>()));
+    }
+  }
+}

extras/tests/JsonDeserializer/object.cpp

@@ -0,0 +1,498 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("deserialize JSON object") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("An empty object") {
+    DeserializationError err = deserializeJson(doc, "{}");
+    JsonObject obj = doc.as<JsonObject>();
+
+    REQUIRE(err == DeserializationError::Ok);
+    REQUIRE(doc.is<JsonObject>());
+    REQUIRE(obj.size() == 0);
+  }
+
+  SECTION("Quotes") {
+    SECTION("Double quotes") {
+      DeserializationError err = deserializeJson(doc, "{\"key\":\"value\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["key"] == "value");
+    }
+
+    SECTION("Single quotes") {
+      DeserializationError err = deserializeJson(doc, "{'key':'value'}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["key"] == "value");
+    }
+
+    SECTION("No quotes") {
+      DeserializationError err = deserializeJson(doc, "{key:'value'}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["key"] == "value");
+    }
+
+    SECTION("No quotes, allow underscore in key") {
+      DeserializationError err = deserializeJson(doc, "{_k_e_y_:42}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["_k_e_y_"] == 42);
+    }
+  }
+
+  SECTION("Spaces") {
+    SECTION("Before the key") {
+      DeserializationError err = deserializeJson(doc, "{ \"key\":\"value\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["key"] == "value");
+    }
+
+    SECTION("After the key") {
+      DeserializationError err = deserializeJson(doc, "{\"key\" :\"value\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["key"] == "value");
+    }
+
+    SECTION("Before the value") {
+      DeserializationError err = deserializeJson(doc, "{\"key\": \"value\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["key"] == "value");
+    }
+
+    SECTION("After the value") {
+      DeserializationError err = deserializeJson(doc, "{\"key\":\"value\" }");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 1);
+      REQUIRE(obj["key"] == "value");
+    }
+
+    SECTION("Before the colon") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"key1\":\"value1\" ,\"key2\":\"value2\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 2);
+      REQUIRE(obj["key1"] == "value1");
+      REQUIRE(obj["key2"] == "value2");
+    }
+
+    SECTION("After the colon") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"key1\":\"value1\" ,\"key2\":\"value2\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 2);
+      REQUIRE(obj["key1"] == "value1");
+      REQUIRE(obj["key2"] == "value2");
+    }
+  }
+
+  SECTION("Values types") {
+    SECTION("String") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"key1\":\"value1\",\"key2\":\"value2\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 2);
+      REQUIRE(obj["key1"] == "value1");
+      REQUIRE(obj["key2"] == "value2");
+    }
+
+    SECTION("Integer") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"key1\":42,\"key2\":-42}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 2);
+      REQUIRE(obj["key1"] == 42);
+      REQUIRE(obj["key2"] == -42);
+    }
+
+    SECTION("Double") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"key1\":12.345,\"key2\":-7E89}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 2);
+      REQUIRE(obj["key1"] == 12.345);
+      REQUIRE(obj["key2"] == -7E89);
+    }
+
+    SECTION("Booleans") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"key1\":true,\"key2\":false}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 2);
+      REQUIRE(obj["key1"] == true);
+      REQUIRE(obj["key2"] == false);
+    }
+
+    SECTION("Null") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"key1\":null,\"key2\":null}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(doc.is<JsonObject>());
+      REQUIRE(obj.size() == 2);
+      REQUIRE(obj["key1"].as<char*>() == 0);
+      REQUIRE(obj["key2"].as<char*>() == 0);
+    }
+
+    SECTION("Array") {
+      char jsonString[] = " { \"ab\" : [ 1 , 2 ] , \"cd\" : [ 3 , 4 ] } ";
+
+      DeserializationError err = deserializeJson(doc, jsonString);
+      JsonObject obj = doc.as<JsonObject>();
+
+      JsonArray array1 = obj["ab"];
+      const JsonArray array2 = obj["cd"];
+      JsonArray array3 = obj["ef"];
+
+      REQUIRE(err == DeserializationError::Ok);
+
+      REQUIRE(array1.isNull() == false);
+      REQUIRE(array2.isNull() == false);
+      REQUIRE(array3.isNull() == true);
+
+      REQUIRE(2 == array1.size());
+      REQUIRE(2 == array2.size());
+      REQUIRE(0 == array3.size());
+
+      REQUIRE(1 == array1[0].as<int>());
+      REQUIRE(2 == array1[1].as<int>());
+
+      REQUIRE(3 == array2[0].as<int>());
+      REQUIRE(4 == array2[1].as<int>());
+
+      REQUIRE(0 == array3[0].as<int>());
+    }
+  }
+
+  SECTION("Premature null terminator") {
+    SECTION("After opening brace") {
+      DeserializationError err = deserializeJson(doc, "{");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After key") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\"");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After colon") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\":");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After value") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\":\"world\"");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+
+    SECTION("After comma") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\":\"world\",");
+
+      REQUIRE(err == DeserializationError::IncompleteInput);
+    }
+  }
+
+  SECTION("Misc") {
+    SECTION("A quoted key without value") {
+      DeserializationError err = deserializeJson(doc, "{\"key\"}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("A non-quoted key without value") {
+      DeserializationError err = deserializeJson(doc, "{key}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("A dangling comma") {
+      DeserializationError err = deserializeJson(doc, "{\"key1\":\"value1\",}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("null as a key") {
+      DeserializationError err = deserializeJson(doc, "{null:\"value\"}");
+
+      REQUIRE(err == DeserializationError::Ok);
+    }
+
+    SECTION("Repeated key") {
+      DeserializationError err = deserializeJson(doc, "{a:{b:{c:1}},a:2}");
+
+      REQUIRE(err == DeserializationError::Ok);
+    }
+  }
+
+  SECTION("Block comments") {
+    SECTION("Before opening brace") {
+      DeserializationError err =
+          deserializeJson(doc, "/*COMMENT*/ {\"hello\":\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("After opening brace") {
+      DeserializationError err =
+          deserializeJson(doc, "{/*COMMENT*/\"hello\":\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("Before colon") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\"/*COMMENT*/:\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("After colon") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\":/*COMMENT*/\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("Before closing brace") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\":\"world\"/*COMMENT*/}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("After closing brace") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\":\"world\"}/*COMMENT*/");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("Before comma") {
+      DeserializationError err = deserializeJson(
+          doc, "{\"hello\":\"world\"/*COMMENT*/,\"answer\":42}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+      REQUIRE(obj["answer"] == 42);
+    }
+
+    SECTION("After comma") {
+      DeserializationError err = deserializeJson(
+          doc, "{\"hello\":\"world\",/*COMMENT*/\"answer\":42}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+      REQUIRE(obj["answer"] == 42);
+    }
+  }
+
+  SECTION("Trailing comments") {
+    SECTION("Before opening brace") {
+      DeserializationError err =
+          deserializeJson(doc, "//COMMENT\n {\"hello\":\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("After opening brace") {
+      DeserializationError err =
+          deserializeJson(doc, "{//COMMENT\n\"hello\":\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("Before colon") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\"//COMMENT\n:\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("After colon") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\"://COMMENT\n\"world\"}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("Before closing brace") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\":\"world\"//COMMENT\n}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("After closing brace") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\":\"world\"}//COMMENT\n");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("Before comma") {
+      DeserializationError err = deserializeJson(
+          doc, "{\"hello\":\"world\"//COMMENT\n,\"answer\":42}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+      REQUIRE(obj["answer"] == 42);
+    }
+
+    SECTION("After comma") {
+      DeserializationError err = deserializeJson(
+          doc, "{\"hello\":\"world\",//COMMENT\n\"answer\":42}");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+      REQUIRE(obj["answer"] == 42);
+    }
+  }
+
+  SECTION("Dangling slash") {
+    SECTION("Before opening brace") {
+      DeserializationError err = deserializeJson(doc, "/{\"hello\":\"world\"}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("After opening brace") {
+      DeserializationError err = deserializeJson(doc, "{/\"hello\":\"world\"}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("Before colon") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\"/:\"world\"}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("After colon") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\":/\"world\"}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("Before closing brace") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\":\"world\"/}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("After closing brace") {
+      DeserializationError err = deserializeJson(doc, "{\"hello\":\"world\"}/");
+      JsonObject obj = doc.as<JsonObject>();
+
+      REQUIRE(err == DeserializationError::Ok);
+      REQUIRE(obj["hello"] == "world");
+    }
+
+    SECTION("Before comma") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\":\"world\"/,\"answer\":42}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+
+    SECTION("After comma") {
+      DeserializationError err =
+          deserializeJson(doc, "{\"hello\":\"world\",/\"answer\":42}");
+
+      REQUIRE(err == DeserializationError::InvalidInput);
+    }
+  }
+
+  SECTION("Should clear the JsonObject") {
+    deserializeJson(doc, "{\"hello\":\"world\"}");
+    deserializeJson(doc, "{}");
+    JsonObject obj = doc.as<JsonObject>();
+
+    REQUIRE(doc.is<JsonObject>());
+    REQUIRE(obj.size() == 0);
+    REQUIRE(doc.memoryUsage() == JSON_OBJECT_SIZE(0));
+  }
+}

extras/tests/JsonDeserializer/object_static.cpp

@@ -0,0 +1,64 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("deserialize JSON object with StaticJsonDocument") {
+  SECTION("BufferOfTheRightSizeForEmptyObject") {
+    StaticJsonDocument<JSON_OBJECT_SIZE(0)> doc;
+    char input[] = "{}";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("TooSmallBufferForObjectWithOneValue") {
+    StaticJsonDocument<JSON_OBJECT_SIZE(0)> doc;
+    char input[] = "{\"a\":1}";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::NoMemory);
+  }
+
+  SECTION("BufferOfTheRightSizeForObjectWithOneValue") {
+    StaticJsonDocument<JSON_OBJECT_SIZE(1)> doc;
+    char input[] = "{\"a\":1}";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("TooSmallBufferForObjectWithNestedObject") {
+    StaticJsonDocument<JSON_OBJECT_SIZE(0) + JSON_ARRAY_SIZE(0)> doc;
+    char input[] = "{\"a\":[]}";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::NoMemory);
+  }
+
+  SECTION("BufferOfTheRightSizeForObjectWithNestedObject") {
+    StaticJsonDocument<JSON_OBJECT_SIZE(1) + JSON_ARRAY_SIZE(0)> doc;
+    char input[] = "{\"a\":[]}";
+
+    DeserializationError err = deserializeJson(doc, input);
+
+    REQUIRE(err == DeserializationError::Ok);
+  }
+
+  SECTION("Should clear the JsonObject") {
+    StaticJsonDocument<JSON_OBJECT_SIZE(1)> doc;
+    char input[] = "{\"hello\":\"world\"}";
+
+    deserializeJson(doc, input);
+    deserializeJson(doc, "{}");
+
+    REQUIRE(doc.as<JsonObject>().size() == 0);
+    REQUIRE(doc.memoryUsage() == JSON_OBJECT_SIZE(0));
+  }
+}

extras/tests/JsonDeserializer/string.cpp

@@ -0,0 +1,72 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#define ARDUINOJSON_DECODE_UNICODE 1
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("Valid JSON strings value") {
+  struct TestCase {
+    const char* input;
+    const char* expectedOutput;
+  };
+
+  TestCase testCases[] = {
+      {"\"hello world\"", "hello world"},
+      {"\'hello world\'", "hello world"},
+      {"\"1\\\"2\\\\3\\/4\\b5\\f6\\n7\\r8\\t9\"", "1\"2\\3/4\b5\f6\n7\r8\t9"},
+      {"'\\u0041'", "A"},
+      {"'\\u00e4'", "\xc3\xa4"},      // ä
+      {"'\\u00E4'", "\xc3\xa4"},      // ä
+      {"'\\u3042'", "\xe3\x81\x82"},  // あ
+
+  };
+  const size_t testCount = sizeof(testCases) / sizeof(testCases[0]);
+
+  DynamicJsonDocument doc(4096);
+
+  for (size_t i = 0; i < testCount; i++) {
+    const TestCase& testCase = testCases[i];
+    CAPTURE(testCase.input);
+    DeserializationError err = deserializeJson(doc, testCase.input);
+    REQUIRE(err == DeserializationError::Ok);
+    REQUIRE(doc.as<std::string>() == testCase.expectedOutput);
+  }
+}
+
+TEST_CASE("Truncated JSON string") {
+  const char* testCases[] = {"\"hello", "\'hello", "'\\u", "'\\u00", "'\\u000"};
+  const size_t testCount = sizeof(testCases) / sizeof(testCases[0]);
+
+  DynamicJsonDocument doc(4096);
+
+  for (size_t i = 0; i < testCount; i++) {
+    const char* input = testCases[i];
+    CAPTURE(input);
+    REQUIRE(deserializeJson(doc, input) ==
+            DeserializationError::IncompleteInput);
+  }
+}
+
+TEST_CASE("Invalid JSON string") {
+  const char* testCases[] = {"'\\u'",     "'\\u000g'", "'\\u000'",
+                             "'\\u000G'", "'\\u000/'", "\\x1234"};
+  const size_t testCount = sizeof(testCases) / sizeof(testCases[0]);
+
+  DynamicJsonDocument doc(4096);
+
+  for (size_t i = 0; i < testCount; i++) {
+    const char* input = testCases[i];
+    CAPTURE(input);
+    REQUIRE(deserializeJson(doc, input) == DeserializationError::InvalidInput);
+  }
+}
+
+TEST_CASE("Not enough room to duplicate the string") {
+  DynamicJsonDocument doc(4);
+
+  REQUIRE(deserializeJson(doc, "\"hello world!\"") ==
+          DeserializationError::NoMemory);
+  REQUIRE(doc.isNull() == true);
+}

extras/tests/JsonDocument/BasicJsonDocument.cpp

@@ -0,0 +1,49 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdlib.h>  // malloc, free
+#include <catch.hpp>
+#include <sstream>
+
+using ARDUINOJSON_NAMESPACE::addPadding;
+
+class SpyingAllocator {
+ public:
+  SpyingAllocator(std::ostream& log) : _log(log) {}
+
+  void* allocate(size_t n) {
+    _log << "A" << n;
+    return malloc(n);
+  }
+  void deallocate(void* p) {
+    _log << "F";
+    free(p);
+  }
+
+ private:
+  SpyingAllocator& operator=(const SpyingAllocator& src);
+
+  std::ostream& _log;
+};
+
+typedef BasicJsonDocument<SpyingAllocator> MyJsonDocument;
+
+TEST_CASE("BasicJsonDocument") {
+  std::stringstream log;
+
+  SECTION("Construct/Destruct") {
+    { MyJsonDocument doc(4096, log); }
+    REQUIRE(log.str() == "A4096F");
+  }
+
+  SECTION("Copy construct") {
+    {
+      MyJsonDocument doc1(4096, log);
+      doc1.set(std::string("The size of this string is 32!!"));
+      MyJsonDocument doc2(doc1);
+    }
+    REQUIRE(log.str() == "A4096A32FF");
+  }
+}

extras/tests/JsonDocument/CMakeLists.txt

@@ -0,0 +1,21 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(JsonDocumentTests
+	add.cpp
+	BasicJsonDocument.cpp
+	compare.cpp
+	containsKey.cpp
+	createNested.cpp
+	DynamicJsonDocument.cpp
+	isNull.cpp
+	nesting.cpp
+	remove.cpp
+	size.cpp
+	StaticJsonDocument.cpp
+	subscript.cpp
+)
+
+target_link_libraries(JsonDocumentTests catch)
+add_test(JsonDocument JsonDocumentTests)

extras/tests/JsonDocument/DynamicJsonDocument.cpp

@@ -0,0 +1,209 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using ARDUINOJSON_NAMESPACE::addPadding;
+
+static void REQUIRE_JSON(JsonDocument& doc, const std::string& expected) {
+  std::string json;
+  serializeJson(doc, json);
+  REQUIRE(json == expected);
+}
+
+TEST_CASE("DynamicJsonDocument") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("serializeJson()") {
+    JsonObject obj = doc.to<JsonObject>();
+    obj["hello"] = "world";
+
+    std::string json;
+    serializeJson(doc, json);
+
+    REQUIRE(json == "{\"hello\":\"world\"}");
+  }
+
+  SECTION("memoryUsage()") {
+    SECTION("starts at zero") {
+      REQUIRE(doc.memoryUsage() == 0);
+    }
+
+    SECTION("JSON_ARRAY_SIZE(0)") {
+      doc.to<JsonArray>();
+      REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(0));
+    }
+
+    SECTION("JSON_ARRAY_SIZE(1)") {
+      doc.to<JsonArray>().add(42);
+      REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(1));
+    }
+
+    SECTION("JSON_ARRAY_SIZE(1) + JSON_ARRAY_SIZE(0)") {
+      doc.to<JsonArray>().createNestedArray();
+      REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(1) + JSON_ARRAY_SIZE(0));
+    }
+  }
+
+  SECTION("capacity()") {
+    SECTION("matches constructor argument") {
+      DynamicJsonDocument doc2(256);
+      REQUIRE(doc2.capacity() == 256);
+    }
+
+    SECTION("rounds up constructor argument") {
+      DynamicJsonDocument doc2(253);
+      REQUIRE(doc2.capacity() == 256);
+    }
+  }
+
+  SECTION("memoryUsage()") {
+    SECTION("Increases after adding value to array") {
+      JsonArray arr = doc.to<JsonArray>();
+
+      REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(0));
+      arr.add(42);
+      REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(1));
+      arr.add(43);
+      REQUIRE(doc.memoryUsage() == JSON_ARRAY_SIZE(2));
+    }
+
+    SECTION("Increases after adding value to object") {
+      JsonObject obj = doc.to<JsonObject>();
+
+      REQUIRE(doc.memoryUsage() == JSON_OBJECT_SIZE(0));
+      obj["a"] = 1;
+      REQUIRE(doc.memoryUsage() == JSON_OBJECT_SIZE(1));
+      obj["b"] = 2;
+      REQUIRE(doc.memoryUsage() == JSON_OBJECT_SIZE(2));
+    }
+  }
+}
+
+TEST_CASE("DynamicJsonDocument constructor") {
+  SECTION("Copy constructor") {
+    DynamicJsonDocument doc1(1234);
+    deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+    DynamicJsonDocument doc2 = doc1;
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+
+    REQUIRE(doc2.capacity() == addPadding(doc1.memoryUsage()));
+  }
+
+  SECTION("Construct from StaticJsonDocument") {
+    StaticJsonDocument<200> doc1;
+    deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+    DynamicJsonDocument doc2 = doc1;
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    REQUIRE(doc2.capacity() == addPadding(doc1.memoryUsage()));
+  }
+
+  SECTION("Construct from JsonObject") {
+    StaticJsonDocument<200> doc1;
+    JsonObject obj = doc1.to<JsonObject>();
+    obj["hello"] = "world";
+
+    DynamicJsonDocument doc2 = obj;
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    REQUIRE(doc2.capacity() == addPadding(doc1.memoryUsage()));
+  }
+
+  SECTION("Construct from JsonArray") {
+    StaticJsonDocument<200> doc1;
+    JsonArray arr = doc1.to<JsonArray>();
+    arr.add("hello");
+
+    DynamicJsonDocument doc2 = arr;
+
+    REQUIRE_JSON(doc2, "[\"hello\"]");
+    REQUIRE(doc2.capacity() == addPadding(doc1.memoryUsage()));
+  }
+
+  SECTION("Construct from JsonVariant") {
+    StaticJsonDocument<200> doc1;
+    deserializeJson(doc1, "42");
+
+    DynamicJsonDocument doc2 = doc1.as<JsonVariant>();
+
+    REQUIRE_JSON(doc2, "42");
+    REQUIRE(doc2.capacity() == addPadding(doc1.memoryUsage()));
+  }
+}
+
+TEST_CASE("DynamicJsonDocument assignment") {
+  SECTION("Copy assignment preserves the buffer when capacity is sufficient") {
+    DynamicJsonDocument doc1(1234);
+    deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+    DynamicJsonDocument doc2(doc1.capacity());
+    doc2 = doc1;
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    REQUIRE(doc2.capacity() == doc1.capacity());
+  }
+
+  SECTION("Copy assignment realloc the buffer when capacity is insufficient") {
+    DynamicJsonDocument doc1(1234);
+    deserializeJson(doc1, "{\"hello\":\"world\"}");
+    DynamicJsonDocument doc2(8);
+
+    REQUIRE(doc2.capacity() < doc1.memoryUsage());
+    doc2 = doc1;
+    REQUIRE(doc2.capacity() >= doc1.memoryUsage());
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+  }
+
+  SECTION("Assign from StaticJsonDocument") {
+    StaticJsonDocument<200> doc1;
+    deserializeJson(doc1, "{\"hello\":\"world\"}");
+    DynamicJsonDocument doc2(4096);
+    doc2.to<JsonVariant>().set(666);
+
+    doc2 = doc1;
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+  }
+
+  SECTION("Assign from JsonObject") {
+    StaticJsonDocument<200> doc1;
+    JsonObject obj = doc1.to<JsonObject>();
+    obj["hello"] = "world";
+
+    DynamicJsonDocument doc2(4096);
+    doc2 = obj;
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    REQUIRE(doc2.capacity() == 4096);
+  }
+
+  SECTION("Assign from JsonArray") {
+    StaticJsonDocument<200> doc1;
+    JsonArray arr = doc1.to<JsonArray>();
+    arr.add("hello");
+
+    DynamicJsonDocument doc2(4096);
+    doc2 = arr;
+
+    REQUIRE_JSON(doc2, "[\"hello\"]");
+    REQUIRE(doc2.capacity() == 4096);
+  }
+
+  SECTION("Assign from JsonVariant") {
+    StaticJsonDocument<200> doc1;
+    deserializeJson(doc1, "42");
+
+    DynamicJsonDocument doc2(4096);
+    doc2 = doc1.as<JsonVariant>();
+
+    REQUIRE_JSON(doc2, "42");
+    REQUIRE(doc2.capacity() == 4096);
+  }
+}

extras/tests/JsonDocument/StaticJsonDocument.cpp

@@ -0,0 +1,212 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+static void REQUIRE_JSON(JsonDocument& doc, const std::string& expected) {
+  std::string json;
+  serializeJson(doc, json);
+  REQUIRE(json == expected);
+}
+
+TEST_CASE("StaticJsonDocument") {
+  SECTION("capacity()") {
+    SECTION("matches template argument") {
+      StaticJsonDocument<256> doc;
+      REQUIRE(doc.capacity() == 256);
+    }
+
+    SECTION("rounds up template argument") {
+      StaticJsonDocument<253> doc;
+      REQUIRE(doc.capacity() == 256);
+    }
+  }
+
+  SECTION("serializeJson()") {
+    StaticJsonDocument<200> doc;
+    JsonObject obj = doc.to<JsonObject>();
+    obj["hello"] = "world";
+
+    std::string json;
+    serializeJson(doc, json);
+
+    REQUIRE(json == "{\"hello\":\"world\"}");
+  }
+
+  SECTION("Copy assignment") {
+    StaticJsonDocument<200> doc1, doc2;
+    doc1.to<JsonVariant>().set(666);
+    deserializeJson(doc2, "{\"hello\":\"world\"}");
+
+    doc1 = doc2;
+
+    REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+  }
+
+  SECTION("Contructor") {
+    SECTION("Copy constructor") {
+      StaticJsonDocument<200> doc1;
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      StaticJsonDocument<200> doc2 = doc1;
+
+      deserializeJson(doc1, "{\"HELLO\":\"WORLD\"}");
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Construct from StaticJsonDocument of different size") {
+      StaticJsonDocument<300> doc1;
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      StaticJsonDocument<200> doc2 = doc1;
+
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Construct from DynamicJsonDocument") {
+      DynamicJsonDocument doc1(4096);
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      StaticJsonDocument<200> doc2 = doc1;
+
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Construct from JsonObject") {
+      DynamicJsonDocument doc1(4096);
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      StaticJsonDocument<200> doc2 = doc1.as<JsonObject>();
+
+      deserializeJson(doc1, "{\"HELLO\":\"WORLD\"}");
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Construct from JsonArray") {
+      DynamicJsonDocument doc1(4096);
+      deserializeJson(doc1, "[\"hello\",\"world\"]");
+
+      StaticJsonDocument<200> doc2 = doc1.as<JsonArray>();
+
+      deserializeJson(doc1, "[\"HELLO\",\"WORLD\"]");
+      REQUIRE_JSON(doc2, "[\"hello\",\"world\"]");
+    }
+
+    SECTION("Construct from JsonVariant") {
+      DynamicJsonDocument doc1(4096);
+      deserializeJson(doc1, "42");
+
+      StaticJsonDocument<200> doc2 = doc1.as<JsonVariant>();
+
+      REQUIRE_JSON(doc2, "42");
+    }
+  }
+
+  SECTION("Assignment") {
+    SECTION("Copy assignment") {
+      StaticJsonDocument<200> doc1, doc2;
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      doc2 = doc1;
+
+      deserializeJson(doc1, "{\"HELLO\":\"WORLD\"}");
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Assign from StaticJsonDocument of different capacity") {
+      StaticJsonDocument<200> doc1;
+      StaticJsonDocument<300> doc2;
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      doc2 = doc1;
+
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Assign from DynamicJsonDocument") {
+      StaticJsonDocument<200> doc1;
+      DynamicJsonDocument doc2(4096);
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      doc2 = doc1;
+
+      deserializeJson(doc1, "{\"HELLO\":\"WORLD\"}");
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Assign from JsonArray") {
+      StaticJsonDocument<200> doc1;
+      DynamicJsonDocument doc2(4096);
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "[\"hello\",\"world\"]");
+
+      doc2 = doc1.as<JsonArray>();
+
+      deserializeJson(doc1, "[\"HELLO\",\"WORLD\"]");
+      REQUIRE_JSON(doc2, "[\"hello\",\"world\"]");
+    }
+
+    SECTION("Assign from JsonArrayConst") {
+      StaticJsonDocument<200> doc1;
+      DynamicJsonDocument doc2(4096);
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "[\"hello\",\"world\"]");
+
+      doc2 = doc1.as<JsonArrayConst>();
+
+      deserializeJson(doc1, "[\"HELLO\",\"WORLD\"]");
+      REQUIRE_JSON(doc2, "[\"hello\",\"world\"]");
+    }
+
+    SECTION("Assign from JsonObject") {
+      StaticJsonDocument<200> doc1;
+      DynamicJsonDocument doc2(4096);
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      doc2 = doc1.as<JsonObject>();
+
+      deserializeJson(doc1, "{\"HELLO\":\"WORLD\"}");
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Assign from JsonObjectConst") {
+      StaticJsonDocument<200> doc1;
+      DynamicJsonDocument doc2(4096);
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "{\"hello\":\"world\"}");
+
+      doc2 = doc1.as<JsonObjectConst>();
+
+      deserializeJson(doc1, "{\"HELLO\":\"WORLD\"}");
+      REQUIRE_JSON(doc2, "{\"hello\":\"world\"}");
+    }
+
+    SECTION("Assign from JsonVariant") {
+      DynamicJsonDocument doc1(4096);
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "42");
+
+      StaticJsonDocument<200> doc2;
+      doc2 = doc1.as<JsonVariant>();
+
+      REQUIRE_JSON(doc2, "42");
+    }
+
+    SECTION("Assign from JsonVariantConst") {
+      DynamicJsonDocument doc1(4096);
+      doc1.to<JsonVariant>().set(666);
+      deserializeJson(doc1, "42");
+
+      StaticJsonDocument<200> doc2;
+      doc2 = doc1.as<JsonVariantConst>();
+
+      REQUIRE_JSON(doc2, "42");
+    }
+  }
+}

extras/tests/JsonDocument/add.cpp

@@ -0,0 +1,22 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::add()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("integer") {
+    doc.add(42);
+
+    REQUIRE(doc.as<std::string>() == "[42]");
+  }
+
+  SECTION("const char*") {
+    doc.add("hello");
+
+    REQUIRE(doc.as<std::string>() == "[\"hello\"]");
+  }
+}

extras/tests/JsonDocument/compare.cpp

@@ -0,0 +1,77 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("DynamicJsonDocument::operator==(const DynamicJsonDocument&)") {
+  DynamicJsonDocument doc1(4096);
+  DynamicJsonDocument doc2(4096);
+
+  SECTION("Empty") {
+    REQUIRE(doc1 == doc2);
+    REQUIRE_FALSE(doc1 != doc2);
+  }
+
+  SECTION("With same object") {
+    doc1["hello"] = "world";
+    doc2["hello"] = "world";
+    REQUIRE(doc1 == doc2);
+    REQUIRE_FALSE(doc1 != doc2);
+  }
+  SECTION("With different object") {
+    doc1["hello"] = "world";
+    doc2["world"] = "hello";
+    REQUIRE_FALSE(doc1 == doc2);
+    REQUIRE(doc1 != doc2);
+  }
+}
+
+TEST_CASE("DynamicJsonDocument::operator==(const StaticJsonDocument&)") {
+  DynamicJsonDocument doc1(4096);
+  StaticJsonDocument<256> doc2;
+
+  SECTION("Empty") {
+    REQUIRE(doc1 == doc2);
+    REQUIRE_FALSE(doc1 != doc2);
+  }
+
+  SECTION("With same object") {
+    doc1["hello"] = "world";
+    doc2["hello"] = "world";
+    REQUIRE(doc1 == doc2);
+    REQUIRE_FALSE(doc1 != doc2);
+  }
+
+  SECTION("With different object") {
+    doc1["hello"] = "world";
+    doc2["world"] = "hello";
+    REQUIRE_FALSE(doc1 == doc2);
+    REQUIRE(doc1 != doc2);
+  }
+}
+
+TEST_CASE("StaticJsonDocument::operator==(const DynamicJsonDocument&)") {
+  StaticJsonDocument<256> doc1;
+  DynamicJsonDocument doc2(4096);
+
+  SECTION("Empty") {
+    REQUIRE(doc1 == doc2);
+    REQUIRE_FALSE(doc1 != doc2);
+  }
+
+  SECTION("With same object") {
+    doc1["hello"] = "world";
+    doc2["hello"] = "world";
+    REQUIRE(doc1 == doc2);
+    REQUIRE_FALSE(doc1 != doc2);
+  }
+
+  SECTION("With different object") {
+    doc1["hello"] = "world";
+    doc2["world"] = "hello";
+    REQUIRE_FALSE(doc1 == doc2);
+    REQUIRE(doc1 != doc2);
+  }
+}

extras/tests/JsonDocument/containsKey.cpp

@@ -0,0 +1,44 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::containsKey()") {
+  DynamicJsonDocument doc(4096);
+
+  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(std::string("hello")) == 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);
+  }
+}

extras/tests/JsonDocument/createNested.cpp

@@ -0,0 +1,66 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::createNestedArray()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("promotes to array") {
+    doc.createNestedArray();
+
+    REQUIRE(doc.is<JsonArray>());
+  }
+}
+
+TEST_CASE("JsonDocument::createNestedArray(key)") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("key is const char*") {
+    SECTION("promotes to object") {
+      doc.createNestedArray("hello");
+
+      REQUIRE(doc.is<JsonObject>());
+    }
+  }
+
+  SECTION("key is std::string") {
+    SECTION("promotes to object") {
+      doc.createNestedArray(std::string("hello"));
+
+      REQUIRE(doc.is<JsonObject>());
+    }
+  }
+}
+
+TEST_CASE("JsonDocument::createNestedObject()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("promotes to array") {
+    doc.createNestedObject();
+
+    REQUIRE(doc.is<JsonArray>());
+  }
+}
+
+TEST_CASE("JsonDocument::createNestedObject(key)") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("key is const char*") {
+    SECTION("promotes to object") {
+      doc.createNestedObject("hello");
+
+      REQUIRE(doc.is<JsonObject>());
+    }
+  }
+
+  SECTION("key is std::string") {
+    SECTION("promotes to object") {
+      doc.createNestedObject(std::string("hello"));
+
+      REQUIRE(doc.is<JsonObject>());
+    }
+  }
+}

extras/tests/JsonDocument/isNull.cpp

@@ -0,0 +1,39 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::isNull()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("returns true if uninitialized") {
+    REQUIRE(doc.isNull() == true);
+  }
+
+  SECTION("returns false after to<JsonObject>()") {
+    doc.to<JsonObject>();
+    REQUIRE(doc.isNull() == false);
+  }
+
+  SECTION("returns false after to<JsonArray>()") {
+    doc.to<JsonArray>();
+    REQUIRE(doc.isNull() == false);
+  }
+
+  SECTION("returns true after to<JsonVariant>()") {
+    REQUIRE(doc.isNull() == true);
+  }
+
+  SECTION("returns false after set()") {
+    doc.to<JsonVariant>().set(42);
+    REQUIRE(doc.isNull() == false);
+  }
+
+  SECTION("returns true after clear()") {
+    doc.to<JsonObject>();
+    doc.clear();
+    REQUIRE(doc.isNull() == true);
+  }
+}

extras/tests/JsonDocument/nesting.cpp

@@ -0,0 +1,30 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::nesting()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("return 0 if uninitialized") {
+    REQUIRE(doc.nesting() == 0);
+  }
+
+  SECTION("returns 0 for string") {
+    JsonVariant var = doc.to<JsonVariant>();
+    var.set("hello");
+    REQUIRE(doc.nesting() == 0);
+  }
+
+  SECTION("returns 1 for empty object") {
+    doc.to<JsonObject>();
+    REQUIRE(doc.nesting() == 1);
+  }
+
+  SECTION("returns 1 for empty array") {
+    doc.to<JsonArray>();
+    REQUIRE(doc.nesting() == 1);
+  }
+}

extras/tests/JsonDocument/remove.cpp

@@ -0,0 +1,52 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::remove()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("remove(int)") {
+    doc.add(1);
+    doc.add(2);
+    doc.add(3);
+
+    doc.remove(1);
+
+    REQUIRE(doc.as<std::string>() == "[1,3]");
+  }
+
+  SECTION("remove(const char *)") {
+    doc["a"] = 1;
+    doc["b"] = 2;
+
+    doc.remove("a");
+
+    REQUIRE(doc.as<std::string>() == "{\"b\":2}");
+  }
+
+  SECTION("remove(std::string)") {
+    doc["a"] = 1;
+    doc["b"] = 2;
+
+    doc.remove(std::string("b"));
+
+    REQUIRE(doc.as<std::string>() == "{\"a\":1}");
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("remove(vla)") {
+    doc["a"] = 1;
+    doc["b"] = 2;
+
+    int i = 4;
+    char vla[i];
+    strcpy(vla, "b");
+    doc.remove(vla);
+
+    REQUIRE(doc.as<std::string>() == "{\"a\":1}");
+  }
+#endif
+}

extras/tests/JsonDocument/size.cpp

@@ -0,0 +1,28 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::size()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("returns 0") {
+    REQUIRE(doc.size() == 0);
+  }
+
+  SECTION("as an array, return 2") {
+    doc.add(1);
+    doc.add(2);
+
+    REQUIRE(doc.size() == 2);
+  }
+
+  SECTION("as an object, return 2") {
+    doc["a"] = 1;
+    doc["b"] = 2;
+
+    REQUIRE(doc.size() == 2);
+  }
+}

extras/tests/JsonDocument/subscript.cpp

@@ -0,0 +1,45 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonDocument::operator[]") {
+  DynamicJsonDocument doc(4096);
+  const JsonDocument& cdoc = doc;
+
+  SECTION("object") {
+    deserializeJson(doc, "{\"hello\":\"world\"}");
+
+    SECTION("const char*") {
+      REQUIRE(doc["hello"] == "world");
+      REQUIRE(cdoc["hello"] == "world");
+    }
+
+    SECTION("std::string") {
+      REQUIRE(doc[std::string("hello")] == "world");
+      REQUIRE(cdoc[std::string("hello")] == "world");
+    }
+
+    SECTION("supports operator|") {
+      REQUIRE((doc["hello"] | "nope") == std::string("world"));
+      REQUIRE((doc["world"] | "nope") == std::string("nope"));
+    }
+  }
+
+  SECTION("array") {
+    deserializeJson(doc, "[\"hello\",\"world\"]");
+
+    REQUIRE(doc[1] == "world");
+    REQUIRE(cdoc[1] == "world");
+  }
+}
+
+TEST_CASE("JsonDocument automatically promotes to object") {
+  DynamicJsonDocument doc(4096);
+
+  doc["one"]["two"]["three"] = 4;
+
+  REQUIRE(doc["one"]["two"]["three"] == 4);
+}

extras/tests/JsonObject/CMakeLists.txt

@@ -0,0 +1,23 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(JsonObjectTests 
+	containsKey.cpp
+	copy.cpp
+	createNestedArray.cpp
+	createNestedObject.cpp
+	equals.cpp
+	invalid.cpp
+	isNull.cpp
+	iterator.cpp
+	memoryUsage.cpp
+	nesting.cpp
+	remove.cpp
+	size.cpp
+	std_string.cpp
+	subscript.cpp
+)
+
+target_link_libraries(JsonObjectTests catch)
+add_test(JsonObject JsonObjectTests)

extras/tests/JsonObject/containsKey.cpp

@@ -0,0 +1,39 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::containsKey()") {
+  DynamicJsonDocument doc(4096);
+  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("works with JsonObjectConst") {
+    JsonObjectConst cobj = obj;
+    REQUIRE(false == cobj.containsKey("world"));
+    REQUIRE(true == cobj.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") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    REQUIRE(true == obj.containsKey(vla));
+  }
+#endif
+}

extras/tests/JsonObject/copy.cpp

@@ -0,0 +1,68 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::set()") {
+  DynamicJsonDocument doc1(4096);
+  DynamicJsonDocument doc2(4096);
+
+  JsonObject obj1 = doc1.to<JsonObject>();
+  JsonObject obj2 = doc2.to<JsonObject>();
+
+  SECTION("doesn't copy static string in key or value") {
+    obj1["hello"] = "world";
+
+    obj2.set(obj1);
+
+    REQUIRE(doc1.memoryUsage() == doc2.memoryUsage());
+    REQUIRE(obj2["hello"] == std::string("world"));
+  }
+
+  SECTION("copy local string value") {
+    obj1["hello"] = std::string("world");
+
+    obj2.set(obj1);
+
+    REQUIRE(doc1.memoryUsage() == doc2.memoryUsage());
+    REQUIRE(obj2["hello"] == std::string("world"));
+  }
+
+  SECTION("copy local key") {
+    obj1[std::string("hello")] = "world";
+
+    obj2.set(obj1);
+
+    REQUIRE(doc1.memoryUsage() == doc2.memoryUsage());
+    REQUIRE(obj2["hello"] == std::string("world"));
+  }
+
+  SECTION("copy string from deserializeJson()") {
+    deserializeJson(doc1, "{'hello':'world'}");
+
+    obj2.set(obj1);
+
+    REQUIRE(doc1.memoryUsage() == doc2.memoryUsage());
+    REQUIRE(obj2["hello"] == std::string("world"));
+  }
+
+  SECTION("copy string from deserializeMsgPack()") {
+    deserializeMsgPack(doc1, "\x81\xA5hello\xA5world");
+
+    obj2.set(obj1);
+
+    REQUIRE(doc1.memoryUsage() == doc2.memoryUsage());
+    REQUIRE(obj2["hello"] == std::string("world"));
+  }
+
+  SECTION("should work with JsonObjectConst") {
+    obj1["hello"] = "world";
+
+    obj2.set(static_cast<JsonObjectConst>(obj1));
+
+    REQUIRE(doc1.memoryUsage() == doc2.memoryUsage());
+    REQUIRE(obj2["hello"] == std::string("world"));
+  }
+}

extras/tests/JsonObject/createNestedArray.cpp

@@ -0,0 +1,27 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::createNestedArray()") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("key is a const char*") {
+    JsonArray arr = obj.createNestedArray("hello");
+    REQUIRE(arr.isNull() == false);
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("key is a VLA") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    JsonArray arr = obj.createNestedArray(vla);
+    REQUIRE(arr.isNull() == false);
+  }
+#endif
+}

extras/tests/JsonObject/createNestedObject.cpp

@@ -0,0 +1,25 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::createNestedObject()") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("key is a const char*") {
+    obj.createNestedObject("hello");
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("key is a VLA") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    obj.createNestedObject(vla);
+  }
+#endif
+}

extras/tests/JsonObject/equals.cpp

@@ -0,0 +1,53 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::operator==()") {
+  DynamicJsonDocument doc1(4096);
+  JsonObject obj1 = doc1.to<JsonObject>();
+  JsonObjectConst obj1c = obj1;
+
+  DynamicJsonDocument doc2(4096);
+  JsonObject obj2 = doc2.to<JsonObject>();
+  JsonObjectConst obj2c = obj2;
+
+  SECTION("should return false when objs differ") {
+    obj1["hello"] = "coucou";
+    obj2["world"] = 1;
+
+    REQUIRE_FALSE(obj1 == obj2);
+    REQUIRE_FALSE(obj1c == obj2c);
+  }
+
+  SECTION("should return false when LHS has more elements") {
+    obj1["hello"] = "coucou";
+    obj1["world"] = 666;
+    obj2["hello"] = "coucou";
+
+    REQUIRE_FALSE(obj1 == obj2);
+    REQUIRE_FALSE(obj1c == obj2c);
+  }
+
+  SECTION("should return false when RKS has more elements") {
+    obj1["hello"] = "coucou";
+    obj2["hello"] = "coucou";
+    obj2["world"] = 666;
+
+    REQUIRE_FALSE(obj1 == obj2);
+    REQUIRE_FALSE(obj1c == obj2c);
+  }
+
+  SECTION("should return true when objs equal") {
+    obj1["hello"] = "world";
+    obj1["anwser"] = 42;
+    // insert in different order
+    obj2["anwser"] = 42;
+    obj2["hello"] = "world";
+
+    REQUIRE(obj1 == obj2);
+    REQUIRE(obj1c == obj2c);
+  }
+}

extras/tests/JsonObject/invalid.cpp

@@ -0,0 +1,35 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace Catch::Matchers;
+
+TEST_CASE("JsonObject::invalid()") {
+  JsonObject obj;
+
+  SECTION("SubscriptFails") {
+    REQUIRE(obj["key"].isNull());
+  }
+
+  SECTION("AddFails") {
+    obj["hello"] = "world";
+    REQUIRE(0 == obj.size());
+  }
+
+  SECTION("CreateNestedArrayFails") {
+    REQUIRE(obj.createNestedArray("hello").isNull());
+  }
+
+  SECTION("CreateNestedObjectFails") {
+    REQUIRE(obj.createNestedObject("world").isNull());
+  }
+
+  SECTION("serialize to 'null'") {
+    char buffer[32];
+    serializeJson(obj, buffer, sizeof(buffer));
+    REQUIRE_THAT(buffer, Equals("null"));
+  }
+}

extras/tests/JsonObject/isNull.cpp

@@ -0,0 +1,34 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::isNull()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("returns true") {
+    JsonObject obj;
+    REQUIRE(obj.isNull() == true);
+  }
+
+  SECTION("returns false") {
+    JsonObject obj = doc.to<JsonObject>();
+    REQUIRE(obj.isNull() == false);
+  }
+}
+
+TEST_CASE("JsonObjectConst::isNull()") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("returns true") {
+    JsonObjectConst obj;
+    REQUIRE(obj.isNull() == true);
+  }
+
+  SECTION("returns false") {
+    JsonObjectConst obj = doc.to<JsonObject>();
+    REQUIRE(obj.isNull() == false);
+  }
+}

extras/tests/JsonObject/iterator.cpp

@@ -0,0 +1,60 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace Catch::Matchers;
+
+TEST_CASE("JsonObject::begin()/end()") {
+  StaticJsonDocument<JSON_OBJECT_SIZE(2)> doc;
+  JsonObject obj = doc.to<JsonObject>();
+  obj["ab"] = 12;
+  obj["cd"] = 34;
+
+  SECTION("NonConstIterator") {
+    JsonObject::iterator it = obj.begin();
+    REQUIRE(obj.end() != it);
+    REQUIRE(it->key() == "ab");
+    REQUIRE(12 == it->value());
+    ++it;
+    REQUIRE(obj.end() != it);
+    REQUIRE(it->key() == "cd");
+    REQUIRE(34 == it->value());
+    ++it;
+    REQUIRE(obj.end() == it);
+  }
+
+  SECTION("Dereferencing end() is safe") {
+    REQUIRE(obj.end()->key().isNull());
+    REQUIRE(obj.end()->value().isNull());
+  }
+}
+
+TEST_CASE("JsonObjectConst::begin()/end()") {
+  StaticJsonDocument<JSON_OBJECT_SIZE(2)> doc;
+  JsonObject obj = doc.to<JsonObject>();
+  obj["ab"] = 12;
+  obj["cd"] = 34;
+
+  JsonObjectConst cobj = obj;
+
+  SECTION("NonConstIterator") {
+    JsonObjectConst::iterator it = cobj.begin();
+    REQUIRE(cobj.end() != it);
+    REQUIRE(it->key() == "ab");
+    REQUIRE(12 == it->value());
+    ++it;
+    REQUIRE(cobj.end() != it);
+    REQUIRE(it->key() == "cd");
+    REQUIRE(34 == it->value());
+    ++it;
+    REQUIRE(cobj.end() == it);
+  }
+
+  SECTION("Dereferencing end() is safe") {
+    REQUIRE(cobj.end()->key().isNull());
+    REQUIRE(cobj.end()->value().isNull());
+  }
+}

extras/tests/JsonObject/memoryUsage.cpp

@@ -0,0 +1,43 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <string>
+
+TEST_CASE("JsonObject::memoryUsage()") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("return 0 if uninitialized") {
+    JsonObject unitialized;
+    REQUIRE(unitialized.memoryUsage() == 0);
+  }
+
+  SECTION("JSON_OBJECT_SIZE(0) for empty object") {
+    REQUIRE(obj.memoryUsage() == JSON_OBJECT_SIZE(0));
+  }
+
+  SECTION("JSON_OBJECT_SIZE(1) after add") {
+    obj["hello"] = 42;
+    REQUIRE(obj.memoryUsage() == JSON_OBJECT_SIZE(1));
+  }
+
+  SECTION("includes the size of the key") {
+    obj[std::string("hello")] = 42;
+    REQUIRE(obj.memoryUsage() == JSON_OBJECT_SIZE(1) + 6);
+  }
+
+  SECTION("includes the size of the nested array") {
+    JsonArray nested = obj.createNestedArray("nested");
+    nested.add(42);
+    REQUIRE(obj.memoryUsage() == JSON_OBJECT_SIZE(1) + JSON_ARRAY_SIZE(1));
+  }
+
+  SECTION("includes the size of the nested object") {
+    JsonObject nested = obj.createNestedObject("nested");
+    nested["hello"] = "world";
+    REQUIRE(obj.memoryUsage() == 2 * JSON_OBJECT_SIZE(1));
+  }
+}

extras/tests/JsonObject/nesting.cpp

@@ -0,0 +1,35 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::nesting()") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("return 0 if uninitialized") {
+    JsonObject unitialized;
+    REQUIRE(unitialized.nesting() == 0);
+  }
+
+  SECTION("returns 1 for empty object") {
+    REQUIRE(obj.nesting() == 1);
+  }
+
+  SECTION("returns 1 for flat object") {
+    obj["hello"] = "world";
+    REQUIRE(obj.nesting() == 1);
+  }
+
+  SECTION("returns 2 with nested array") {
+    obj.createNestedArray("nested");
+    REQUIRE(obj.nesting() == 2);
+  }
+
+  SECTION("returns 2 with nested object") {
+    obj.createNestedObject("nested");
+    REQUIRE(obj.nesting() == 2);
+  }
+}

extras/tests/JsonObject/remove.cpp

@@ -0,0 +1,72 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <string>
+
+TEST_CASE("JsonObject::remove()") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+  obj["a"] = 0;
+  obj["b"] = 1;
+  obj["c"] = 2;
+  std::string result;
+
+  SECTION("remove(key)") {
+    SECTION("Remove first") {
+      obj.remove("a");
+      serializeJson(obj, result);
+      REQUIRE("{\"b\":1,\"c\":2}" == result);
+    }
+
+    SECTION("Remove middle") {
+      obj.remove("b");
+      serializeJson(obj, result);
+      REQUIRE("{\"a\":0,\"c\":2}" == result);
+    }
+
+    SECTION("Remove last") {
+      obj.remove("c");
+      serializeJson(obj, result);
+      REQUIRE("{\"a\":0,\"b\":1}" == result);
+    }
+  }
+
+  SECTION("remove(iterator)") {
+    JsonObject::iterator it = obj.begin();
+
+    SECTION("Remove first") {
+      obj.remove(it);
+      serializeJson(obj, result);
+      REQUIRE("{\"b\":1,\"c\":2}" == result);
+    }
+
+    SECTION("Remove middle") {
+      ++it;
+      obj.remove(it);
+      serializeJson(obj, result);
+      REQUIRE("{\"a\":0,\"c\":2}" == result);
+    }
+
+    SECTION("Remove last") {
+      it += 2;
+      obj.remove(it);
+      serializeJson(obj, result);
+      REQUIRE("{\"a\":0,\"b\":1}" == result);
+    }
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("key is a vla") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "b");
+    obj.remove(vla);
+
+    serializeJson(obj, result);
+    REQUIRE("{\"a\":0,\"c\":2}" == result);
+  }
+#endif
+}

extras/tests/JsonObject/size.cpp

@@ -0,0 +1,39 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <string>
+
+TEST_CASE("JsonObject::size()") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("initial size is zero") {
+    REQUIRE(0 == obj.size());
+  }
+
+  SECTION("increases when values are added") {
+    obj["hello"] = 42;
+    REQUIRE(1 == obj.size());
+  }
+
+  SECTION("decreases when values are removed") {
+    obj["hello"] = 42;
+    obj.remove("hello");
+    REQUIRE(0 == obj.size());
+  }
+
+  SECTION("doesn't increase when the same key is added twice") {
+    obj["hello"] = 1;
+    obj["hello"] = 2;
+    REQUIRE(1 == obj.size());
+  }
+
+  SECTION("doesn't decrease when another key is removed") {
+    obj["hello"] = 1;
+    obj.remove("world");
+    REQUIRE(1 == obj.size());
+  }
+}

extras/tests/JsonObject/std_string.cpp

@@ -0,0 +1,109 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+static void eraseString(std::string &str) {
+  char *p = const_cast<char *>(str.c_str());
+  while (*p) *p++ = '*';
+}
+
+TEST_CASE("std::string") {
+  DynamicJsonDocument doc(4096);
+
+  SECTION("operator[]") {
+    char json[] = "{\"key\":\"value\"}";
+
+    deserializeJson(doc, json);
+    JsonObject obj = doc.as<JsonObject>();
+
+    REQUIRE(std::string("value") == obj[std::string("key")]);
+  }
+
+  SECTION("operator[] const") {
+    char json[] = "{\"key\":\"value\"}";
+
+    deserializeJson(doc, json);
+    JsonObject obj = doc.as<JsonObject>();
+
+    REQUIRE(std::string("value") == obj[std::string("key")]);
+  }
+
+  SECTION("createNestedObject()") {
+    JsonObject obj = doc.to<JsonObject>();
+    std::string key = "key";
+    char json[64];
+    obj.createNestedObject(key);
+    eraseString(key);
+    serializeJson(doc, json, sizeof(json));
+    REQUIRE(std::string("{\"key\":{}}") == json);
+  }
+
+  SECTION("createNestedArray()") {
+    JsonObject obj = doc.to<JsonObject>();
+    std::string key = "key";
+    char json[64];
+    obj.createNestedArray(key);
+    eraseString(key);
+    serializeJson(doc, json, sizeof(json));
+    REQUIRE(std::string("{\"key\":[]}") == json);
+  }
+
+  SECTION("containsKey()") {
+    char json[] = "{\"key\":\"value\"}";
+    deserializeJson(doc, json);
+    JsonObject obj = doc.as<JsonObject>();
+    REQUIRE(true == obj.containsKey(std::string("key")));
+  }
+
+  SECTION("remove()") {
+    JsonObject obj = doc.to<JsonObject>();
+    obj["key"] = "value";
+
+    obj.remove(std::string("key"));
+
+    REQUIRE(0 == obj.size());
+  }
+
+  SECTION("operator[], set key") {
+    std::string key("hello");
+    JsonObject obj = doc.to<JsonObject>();
+    obj[key] = "world";
+    eraseString(key);
+    REQUIRE(std::string("world") == obj["hello"]);
+  }
+
+  SECTION("operator[], set value") {
+    std::string value("world");
+    JsonObject obj = doc.to<JsonObject>();
+    obj["hello"] = value;
+    eraseString(value);
+    REQUIRE(std::string("world") == obj["hello"]);
+  }
+
+  SECTION("memoryUsage() increases when adding a new key") {
+    std::string key1("hello"), key2("world");
+    JsonObject obj = doc.to<JsonObject>();
+
+    obj[key1] = 1;
+    size_t sizeBefore = doc.memoryUsage();
+    obj[key2] = 2;
+    size_t sizeAfter = doc.memoryUsage();
+
+    REQUIRE(sizeAfter - sizeBefore >= key2.size());
+  }
+
+  SECTION("memoryUsage() remains when adding the same key") {
+    std::string key("hello");
+    JsonObject obj = doc.to<JsonObject>();
+
+    obj[key] = 1;
+    size_t sizeBefore = doc.memoryUsage();
+    obj[key] = 2;
+    size_t sizeAfter = doc.memoryUsage();
+
+    REQUIRE(sizeBefore == sizeAfter);
+  }
+}

extras/tests/JsonObject/subscript.cpp

@@ -0,0 +1,234 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonObject::operator[]") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("int") {
+    obj["hello"] = 123;
+
+    REQUIRE(123 == obj["hello"].as<int>());
+    REQUIRE(true == obj["hello"].is<int>());
+    REQUIRE(false == obj["hello"].is<bool>());
+  }
+
+  SECTION("volatile int") {  // issue #415
+    volatile int i = 123;
+    obj["hello"] = i;
+
+    REQUIRE(123 == obj["hello"].as<int>());
+    REQUIRE(true == obj["hello"].is<int>());
+    REQUIRE(false == obj["hello"].is<bool>());
+  }
+
+  SECTION("double") {
+    obj["hello"] = 123.45;
+
+    REQUIRE(true == obj["hello"].is<double>());
+    REQUIRE(false == obj["hello"].is<long>());
+    REQUIRE(123.45 == obj["hello"].as<double>());
+  }
+
+  SECTION("bool") {
+    obj["hello"] = true;
+
+    REQUIRE(true == obj["hello"].is<bool>());
+    REQUIRE(false == obj["hello"].is<long>());
+    REQUIRE(true == obj["hello"].as<bool>());
+  }
+
+  SECTION("const char*") {
+    obj["hello"] = "h3110";
+
+    REQUIRE(true == obj["hello"].is<const char*>());
+    REQUIRE(false == obj["hello"].is<long>());
+    REQUIRE(std::string("h3110") == obj["hello"].as<const char*>());
+    REQUIRE(std::string("h3110") == obj["hello"].as<char*>());  // <- short hand
+  }
+
+  SECTION("array") {
+    DynamicJsonDocument doc2(4096);
+    JsonArray arr = doc2.to<JsonArray>();
+
+    obj["hello"] = arr;
+
+    REQUIRE(arr == obj["hello"].as<JsonArray>());
+    REQUIRE(true == obj["hello"].is<JsonArray>());
+    REQUIRE(false == obj["hello"].is<JsonObject>());
+  }
+
+  SECTION("object") {
+    DynamicJsonDocument doc2(4096);
+    JsonObject obj2 = doc2.to<JsonObject>();
+
+    obj["hello"] = obj2;
+
+    REQUIRE(obj2 == obj["hello"].as<JsonObject>());
+    REQUIRE(true == obj["hello"].is<JsonObject>());
+    REQUIRE(false == obj["hello"].is<JsonArray>());
+  }
+
+  SECTION("array subscript") {
+    DynamicJsonDocument doc2(4096);
+    JsonArray arr = doc2.to<JsonArray>();
+    arr.add(42);
+
+    obj["a"] = arr[0];
+
+    REQUIRE(42 == obj["a"]);
+  }
+
+  SECTION("object subscript") {
+    DynamicJsonDocument doc2(4096);
+    JsonObject obj2 = doc2.to<JsonObject>();
+    obj2["x"] = 42;
+
+    obj["a"] = obj2["x"];
+
+    REQUIRE(42 == obj["a"]);
+  }
+
+  SECTION("char key[]") {  // issue #423
+    char key[] = "hello";
+    obj[key] = 42;
+    REQUIRE(42 == obj[key]);
+  }
+
+  SECTION("should not duplicate const char*") {
+    obj["hello"] = "world";
+    const size_t expectedSize = JSON_OBJECT_SIZE(1);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate char* value") {
+    obj["hello"] = const_cast<char*>("world");
+    const size_t expectedSize = JSON_OBJECT_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate char* key") {
+    obj[const_cast<char*>("hello")] = "world";
+    const size_t expectedSize = JSON_OBJECT_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate char* key&value") {
+    obj[const_cast<char*>("hello")] = const_cast<char*>("world");
+    const size_t expectedSize = JSON_OBJECT_SIZE(1) + 2 * JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize <= doc.memoryUsage());
+  }
+
+  SECTION("should duplicate std::string value") {
+    obj["hello"] = std::string("world");
+    const size_t expectedSize = JSON_OBJECT_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate std::string key") {
+    obj[std::string("hello")] = "world";
+    const size_t expectedSize = JSON_OBJECT_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should duplicate std::string key&value") {
+    obj[std::string("hello")] = std::string("world");
+    const size_t expectedSize = JSON_OBJECT_SIZE(1) + 2 * JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize <= doc.memoryUsage());
+  }
+
+  SECTION("should duplicate a non-static JsonString key") {
+    obj[JsonString("hello", false)] = "world";
+    const size_t expectedSize = JSON_OBJECT_SIZE(1) + JSON_STRING_SIZE(6);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should not duplicate a static JsonString key") {
+    obj[JsonString("hello", true)] = "world";
+    const size_t expectedSize = JSON_OBJECT_SIZE(1);
+    REQUIRE(expectedSize == doc.memoryUsage());
+  }
+
+  SECTION("should ignore null key") {
+    // object must have a value to make a call to strcmp()
+    obj["dummy"] = 42;
+
+    const char* null = 0;
+    obj[null] = 666;
+
+    REQUIRE(obj.size() == 1);
+    REQUIRE(obj[null] == null);
+  }
+
+  SECTION("obj[key].to<JsonArray>()") {
+    JsonArray arr = obj["hello"].to<JsonArray>();
+
+    REQUIRE(arr.isNull() == false);
+  }
+
+#if defined(HAS_VARIABLE_LENGTH_ARRAY) && \
+    !defined(SUBSCRIPT_CONFLICTS_WITH_BUILTIN_OPERATOR)
+  SECTION("obj[VLA] = str") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    obj[vla] = "world";
+
+    REQUIRE(std::string("world") == obj["hello"]);
+  }
+
+  SECTION("obj[str] = VLA") {  // issue #416
+    int i = 32;
+    char vla[i];
+    strcpy(vla, "world");
+
+    obj["hello"] = vla;
+
+    REQUIRE(std::string("world") == obj["hello"].as<char*>());
+  }
+
+  SECTION("obj.set(VLA, str)") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    obj[vla] = "world";
+
+    REQUIRE(std::string("world") == obj["hello"]);
+  }
+
+  SECTION("obj.set(str, VLA)") {
+    int i = 32;
+    char vla[i];
+    strcpy(vla, "world");
+
+    obj["hello"].set(vla);
+
+    REQUIRE(std::string("world") == obj["hello"].as<char*>());
+  }
+
+  SECTION("obj[VLA]") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    deserializeJson(doc, "{\"hello\":\"world\"}");
+
+    obj = doc.as<JsonObject>();
+    REQUIRE(std::string("world") == obj[vla]);
+  }
+#endif
+
+  SECTION("chain") {
+    obj.createNestedObject("hello")["world"] = 123;
+
+    REQUIRE(123 == obj["hello"]["world"].as<int>());
+    REQUIRE(true == obj["hello"]["world"].is<int>());
+    REQUIRE(false == obj["hello"]["world"].is<bool>());
+  }
+}

extras/tests/JsonSerializer/CMakeLists.txt

@@ -0,0 +1,17 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(JsonSerializerTests
+	JsonArray.cpp
+	JsonArrayPretty.cpp
+	JsonObject.cpp
+	JsonObjectPretty.cpp
+	JsonVariant.cpp
+	misc.cpp
+	std_stream.cpp
+	std_string.cpp
+)
+
+target_link_libraries(JsonSerializerTests catch)
+add_test(JsonSerializer JsonSerializerTests)

extras/tests/JsonSerializer/JsonArray.cpp

@@ -0,0 +1,129 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+static void check(JsonArray array, std::string expected) {
+  std::string actual;
+  size_t actualLen = serializeJson(array, actual);
+  REQUIRE(expected == actual);
+  REQUIRE(actualLen == expected.size());
+  size_t measuredLen = measureJson(array);
+  REQUIRE(measuredLen == expected.size());
+}
+
+TEST_CASE("serializeJson(JsonArray)") {
+  StaticJsonDocument<JSON_ARRAY_SIZE(2)> doc;
+  JsonArray array = doc.to<JsonArray>();
+
+  SECTION("Empty") {
+    check(array, "[]");
+  }
+
+  SECTION("Null") {
+    array.add(static_cast<char *>(0));
+
+    check(array, "[null]");
+  }
+
+  SECTION("OneString") {
+    array.add("hello");
+
+    check(array, "[\"hello\"]");
+  }
+
+  SECTION("TwoStrings") {
+    array.add("hello");
+    array.add("world");
+
+    check(array, "[\"hello\",\"world\"]");
+  }
+
+  SECTION("OneStringOverCapacity") {
+    array.add("hello");
+    array.add("world");
+    array.add("lost");
+
+    check(array, "[\"hello\",\"world\"]");
+  }
+
+  SECTION("One double") {
+    array.add(3.1415927);
+    check(array, "[3.1415927]");
+  }
+
+  SECTION("OneInteger") {
+    array.add(1);
+
+    check(array, "[1]");
+  }
+
+  SECTION("TwoIntegers") {
+    array.add(1);
+    array.add(2);
+
+    check(array, "[1,2]");
+  }
+
+  SECTION("serialized(const char*)") {
+    array.add(serialized("{\"key\":\"value\"}"));
+
+    check(array, "[{\"key\":\"value\"}]");
+  }
+
+  SECTION("serialized(char*)") {
+    char tmp[] = "{\"key\":\"value\"}";
+    array.add(serialized(tmp));
+
+    check(array, "[{\"key\":\"value\"}]");
+  }
+
+  SECTION("OneIntegerOverCapacity") {
+    array.add(1);
+    array.add(2);
+    array.add(3);
+
+    check(array, "[1,2]");
+  }
+
+  SECTION("OneTrue") {
+    array.add(true);
+
+    check(array, "[true]");
+  }
+
+  SECTION("OneFalse") {
+    array.add(false);
+
+    check(array, "[false]");
+  }
+
+  SECTION("TwoBooleans") {
+    array.add(false);
+    array.add(true);
+
+    check(array, "[false,true]");
+  }
+
+  SECTION("OneBooleanOverCapacity") {
+    array.add(false);
+    array.add(true);
+    array.add(false);
+
+    check(array, "[false,true]");
+  }
+
+  SECTION("OneEmptyNestedArray") {
+    array.createNestedArray();
+
+    check(array, "[[]]");
+  }
+
+  SECTION("OneEmptyNestedHash") {
+    array.createNestedObject();
+
+    check(array, "[{}]");
+  }
+}

extras/tests/JsonSerializer/JsonArrayPretty.cpp

@@ -0,0 +1,75 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+static void check(JsonArray array, std::string expected) {
+  std::string actual;
+  size_t actualLen = serializeJsonPretty(array, actual);
+  size_t measuredLen = measureJsonPretty(array);
+  CHECK(actualLen == expected.size());
+  CHECK(measuredLen == expected.size());
+  REQUIRE(expected == actual);
+}
+
+TEST_CASE("serializeJsonPretty(JsonArray)") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+
+  SECTION("Empty") {
+    check(array, "[]");
+  }
+
+  SECTION("OneElement") {
+    array.add(1);
+
+    check(array,
+          "[\r\n"
+          "  1\r\n"
+          "]");
+  }
+
+  SECTION("TwoElements") {
+    array.add(1);
+    array.add(2);
+
+    check(array,
+          "[\r\n"
+          "  1,\r\n"
+          "  2\r\n"
+          "]");
+  }
+
+  SECTION("EmptyNestedArrays") {
+    array.createNestedArray();
+    array.createNestedArray();
+
+    check(array,
+          "[\r\n"
+          "  [],\r\n"
+          "  []\r\n"
+          "]");
+  }
+
+  SECTION("NestedArrays") {
+    JsonArray nested1 = array.createNestedArray();
+    nested1.add(1);
+    nested1.add(2);
+
+    JsonObject nested2 = array.createNestedObject();
+    nested2["key"] = 3;
+
+    check(array,
+          "[\r\n"
+          "  [\r\n"
+          "    1,\r\n"
+          "    2\r\n"
+          "  ],\r\n"
+          "  {\r\n"
+          "    \"key\": 3\r\n"
+          "  }\r\n"
+          "]");
+  }
+}

extras/tests/JsonSerializer/JsonObject.cpp

@@ -0,0 +1,116 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <string>
+
+void check(const JsonObject obj, const std::string &expected) {
+  char actual[256];
+  size_t actualLen = serializeJson(obj, actual);
+  size_t measuredLen = measureJson(obj);
+
+  REQUIRE(expected == actual);
+  REQUIRE(expected.size() == actualLen);
+  REQUIRE(expected.size() == measuredLen);
+}
+
+TEST_CASE("serializeJson(JsonObject)") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("EmptyObject") {
+    check(obj, "{}");
+  }
+
+  SECTION("TwoStrings") {
+    obj["key1"] = "value1";
+    obj["key2"] = "value2";
+
+    check(obj, "{\"key1\":\"value1\",\"key2\":\"value2\"}");
+  }
+
+  SECTION("RemoveFirst") {
+    obj["key1"] = "value1";
+    obj["key2"] = "value2";
+    obj.remove("key1");
+
+    check(obj, "{\"key2\":\"value2\"}");
+  }
+
+  SECTION("RemoveLast") {
+    obj["key1"] = "value1";
+    obj["key2"] = "value2";
+    obj.remove("key2");
+
+    check(obj, "{\"key1\":\"value1\"}");
+  }
+
+  SECTION("RemoveUnexistingKey") {
+    obj["key1"] = "value1";
+    obj["key2"] = "value2";
+    obj.remove("key3");
+
+    check(obj, "{\"key1\":\"value1\",\"key2\":\"value2\"}");
+  }
+
+  SECTION("ReplaceExistingKey") {
+    obj["key"] = "value1";
+    obj["key"] = "value2";
+
+    check(obj, "{\"key\":\"value2\"}");
+  }
+
+  SECTION("TwoIntegers") {
+    obj["a"] = 1;
+    obj["b"] = 2;
+    check(obj, "{\"a\":1,\"b\":2}");
+  }
+
+  SECTION("serialized(const char*)") {
+    obj["a"] = serialized("[1,2]");
+    obj["b"] = serialized("[4,5]");
+    check(obj, "{\"a\":[1,2],\"b\":[4,5]}");
+  }
+
+  SECTION("Two doubles") {
+    obj["a"] = 12.34;
+    obj["b"] = 56.78;
+    check(obj, "{\"a\":12.34,\"b\":56.78}");
+  }
+
+  SECTION("TwoNull") {
+    obj["a"] = static_cast<char *>(0);
+    obj["b"] = static_cast<char *>(0);
+    check(obj, "{\"a\":null,\"b\":null}");
+  }
+
+  SECTION("TwoBooleans") {
+    obj["a"] = true;
+    obj["b"] = false;
+    check(obj, "{\"a\":true,\"b\":false}");
+  }
+
+  SECTION("ThreeNestedArrays") {
+    DynamicJsonDocument b(4096);
+    DynamicJsonDocument c(4096);
+
+    obj.createNestedArray("a");
+    obj["b"] = b.to<JsonArray>();
+    obj["c"] = c.to<JsonArray>();
+
+    check(obj, "{\"a\":[],\"b\":[],\"c\":[]}");
+  }
+
+  SECTION("ThreeNestedObjects") {
+    DynamicJsonDocument b(4096);
+    DynamicJsonDocument c(4096);
+
+    obj.createNestedObject("a");
+    obj["b"] = b.to<JsonObject>();
+    obj["c"] = c.to<JsonObject>();
+
+    check(obj, "{\"a\":{},\"b\":{},\"c\":{}}");
+  }
+}

extras/tests/JsonSerializer/JsonObjectPretty.cpp

@@ -0,0 +1,76 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <string>
+
+void check(const JsonObject obj, const std::string expected) {
+  char json[256];
+
+  size_t actualLen = serializeJsonPretty(obj, json);
+  size_t measuredLen = measureJsonPretty(obj);
+
+  REQUIRE(json == expected);
+  REQUIRE(expected.size() == actualLen);
+  REQUIRE(expected.size() == measuredLen);
+}
+
+TEST_CASE("serializeJsonPretty(JsonObject)") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+
+  SECTION("EmptyObject") {
+    check(obj, "{}");
+  }
+
+  SECTION("OneMember") {
+    obj["key"] = "value";
+
+    check(obj,
+          "{\r\n"
+          "  \"key\": \"value\"\r\n"
+          "}");
+  }
+
+  SECTION("TwoMembers") {
+    obj["key1"] = "value1";
+    obj["key2"] = "value2";
+
+    check(obj,
+          "{\r\n"
+          "  \"key1\": \"value1\",\r\n"
+          "  \"key2\": \"value2\"\r\n"
+          "}");
+  }
+
+  SECTION("EmptyNestedContainers") {
+    obj.createNestedObject("key1");
+    obj.createNestedArray("key2");
+
+    check(obj,
+          "{\r\n"
+          "  \"key1\": {},\r\n"
+          "  \"key2\": []\r\n"
+          "}");
+  }
+
+  SECTION("NestedContainers") {
+    JsonObject nested1 = obj.createNestedObject("key1");
+    nested1["a"] = 1;
+
+    JsonArray nested2 = obj.createNestedArray("key2");
+    nested2.add(2);
+
+    check(obj,
+          "{\r\n"
+          "  \"key1\": {\r\n"
+          "    \"a\": 1\r\n"
+          "  },\r\n"
+          "  \"key2\": [\r\n"
+          "    2\r\n"
+          "  ]\r\n"
+          "}");
+  }
+}

extras/tests/JsonSerializer/JsonVariant.cpp

@@ -0,0 +1,85 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <limits>
+
+template <typename T>
+void check(T value, const std::string &expected) {
+  DynamicJsonDocument doc(4096);
+  doc.to<JsonVariant>().set(value);
+  char buffer[256] = "";
+  size_t returnValue = serializeJson(doc, buffer, sizeof(buffer));
+  REQUIRE(expected == buffer);
+  REQUIRE(expected.size() == returnValue);
+}
+
+TEST_CASE("serializeJson(JsonVariant)") {
+  SECTION("Undefined") {
+    check(JsonVariant(), "null");
+  }
+
+  SECTION("Null string") {
+    check(static_cast<char *>(0), "null");
+  }
+
+  SECTION("const char*") {
+    check("hello", "\"hello\"");
+  }
+
+  SECTION("string") {
+    check(std::string("hello"), "\"hello\"");
+  }
+
+  SECTION("SerializedValue<const char*>") {
+    check(serialized("[1,2]"), "[1,2]");
+  }
+
+  SECTION("SerializedValue<std::string>") {
+    check(serialized(std::string("[1,2]")), "[1,2]");
+  }
+
+  SECTION("Double") {
+    check(3.1415927, "3.1415927");
+  }
+
+  SECTION("Zero") {
+    check(0, "0");
+  }
+
+  SECTION("Integer") {
+    check(42, "42");
+  }
+
+  SECTION("NegativeLong") {
+    check(-42, "-42");
+  }
+
+  SECTION("UnsignedLong") {
+    check(4294967295UL, "4294967295");
+  }
+
+  SECTION("True") {
+    check(true, "true");
+  }
+
+  SECTION("OneFalse") {
+    check(false, "false");
+  }
+
+#if ARDUINOJSON_USE_LONG_LONG
+  SECTION("NegativeInt64") {
+    check(-9223372036854775807 - 1, "-9223372036854775808");
+  }
+
+  SECTION("PositiveInt64") {
+    check(9223372036854775807, "9223372036854775807");
+  }
+
+  SECTION("UInt64") {
+    check(18446744073709551615U, "18446744073709551615");
+  }
+#endif
+}

extras/tests/JsonSerializer/misc.cpp

@@ -0,0 +1,46 @@
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <limits>
+
+template <typename T>
+void check(T value, const std::string &expected) {
+  DynamicJsonDocument doc(4096);
+  doc.to<JsonVariant>().set(value);
+  char buffer[256] = "";
+  size_t returnValue = serializeJson(doc, buffer, sizeof(buffer));
+  REQUIRE(expected == buffer);
+  REQUIRE(expected.size() == returnValue);
+}
+
+TEST_CASE("serializeJson(MemberProxy)") {
+  DynamicJsonDocument doc(4096);
+  deserializeJson(doc, "{\"hello\":42}");
+  JsonObject obj = doc.as<JsonObject>();
+  std::string result;
+
+  serializeJson(obj["hello"], result);
+
+  REQUIRE(result == "42");
+}
+
+TEST_CASE("serializeJson(ElementProxy)") {
+  DynamicJsonDocument doc(4096);
+  deserializeJson(doc, "[42]");
+  JsonArray arr = doc.as<JsonArray>();
+  std::string result;
+
+  serializeJson(arr[0], result);
+
+  REQUIRE(result == "42");
+}
+
+TEST_CASE("serializeJson(JsonVariantSubscript)") {
+  DynamicJsonDocument doc(4096);
+  deserializeJson(doc, "[42]");
+  JsonVariant var = doc.as<JsonVariant>();
+  std::string result;
+
+  serializeJson(var[0], result);
+
+  REQUIRE(result == "42");
+}

extras/tests/JsonSerializer/std_stream.cpp

@@ -0,0 +1,66 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <sstream>
+
+TEST_CASE("operator<<(std::ostream)") {
+  DynamicJsonDocument doc(4096);
+  std::ostringstream os;
+
+  SECTION("JsonVariant containing false") {
+    JsonVariant variant = doc.to<JsonVariant>();
+
+    variant.set(false);
+    os << variant;
+
+    REQUIRE("false" == os.str());
+  }
+
+  SECTION("JsonVariant containing string") {
+    JsonVariant variant = doc.to<JsonVariant>();
+
+    variant.set("coucou");
+    os << variant;
+
+    REQUIRE("\"coucou\"" == os.str());
+  }
+
+  SECTION("JsonObject") {
+    JsonObject object = doc.to<JsonObject>();
+    object["key"] = "value";
+
+    os << object;
+
+    REQUIRE("{\"key\":\"value\"}" == os.str());
+  }
+
+  SECTION("MemberProxy") {
+    JsonObject object = doc.to<JsonObject>();
+    object["key"] = "value";
+
+    os << object["key"];
+
+    REQUIRE("\"value\"" == os.str());
+  }
+
+  SECTION("JsonArray") {
+    JsonArray array = doc.to<JsonArray>();
+    array.add("value");
+
+    os << array;
+
+    REQUIRE("[\"value\"]" == os.str());
+  }
+
+  SECTION("ElementProxy") {
+    JsonArray array = doc.to<JsonArray>();
+    array.add("value");
+
+    os << array[0];
+
+    REQUIRE("\"value\"" == os.str());
+  }
+}

extras/tests/JsonSerializer/std_string.cpp

@@ -0,0 +1,47 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("serialize JsonArray to std::string") {
+  DynamicJsonDocument doc(4096);
+  JsonArray array = doc.to<JsonArray>();
+  array.add(4);
+  array.add(2);
+
+  SECTION("serializeJson()") {
+    std::string json;
+    serializeJson(array, json);
+
+    REQUIRE("[4,2]" == json);
+  }
+
+  SECTION("serializeJsonPretty") {
+    std::string json;
+    serializeJsonPretty(array, json);
+
+    REQUIRE("[\r\n  4,\r\n  2\r\n]" == json);
+  }
+}
+
+TEST_CASE("serialize JsonObject to std::string") {
+  DynamicJsonDocument doc(4096);
+  JsonObject obj = doc.to<JsonObject>();
+  obj["key"] = "value";
+
+  SECTION("object") {
+    std::string json;
+    serializeJson(doc, json);
+
+    REQUIRE("{\"key\":\"value\"}" == json);
+  }
+
+  SECTION("serializeJsonPretty") {
+    std::string json;
+    serializeJsonPretty(doc, json);
+
+    REQUIRE("{\r\n  \"key\": \"value\"\r\n}" == json);
+  }
+}

extras/tests/JsonVariant/CMakeLists.txt

@@ -0,0 +1,28 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(JsonVariantTests
+	add.cpp
+	as.cpp
+	clear.cpp
+	compare.cpp
+	containsKey.cpp
+	copy.cpp
+	createNested.cpp
+	is.cpp
+	isnull.cpp
+	memoryUsage.cpp
+	misc.cpp
+	nesting.cpp
+	or.cpp
+	overflow.cpp
+	remove.cpp
+	set.cpp
+	subscript.cpp
+	types.cpp
+	undefined.cpp
+)
+
+target_link_libraries(JsonVariantTests catch)
+add_test(JsonVariant JsonVariantTests)

extras/tests/JsonVariant/add.cpp

@@ -0,0 +1,32 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+
+static const char* null = 0;
+
+TEST_CASE("JsonVariant::add()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("integer") {
+    var.add(42);
+
+    REQUIRE(var.as<std::string>() == "[42]");
+  }
+
+  SECTION("const char*") {
+    var.add("hello");
+
+    REQUIRE(var.as<std::string>() == "[\"hello\"]");
+  }
+
+  SECTION("std::string") {
+    var.add(std::string("hello"));
+
+    REQUIRE(var.as<std::string>() == "[\"hello\"]");
+  }
+}

extras/tests/JsonVariant/as.cpp

@@ -0,0 +1,215 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+
+namespace my {
+using ARDUINOJSON_NAMESPACE::isinf;
+}  // namespace my
+
+static const char* null = 0;
+
+TEST_CASE("JsonVariant::as()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("not set") {
+    REQUIRE(false == variant.as<bool>());
+    REQUIRE(0 == variant.as<int>());
+    REQUIRE(0.0f == variant.as<float>());
+    REQUIRE(0 == variant.as<char*>());
+    REQUIRE("null" == variant.as<std::string>());
+  }
+
+  SECTION("set(4.2)") {
+    variant.set(4.2);
+
+    REQUIRE(variant.as<bool>());
+    REQUIRE(0 == variant.as<const char*>());
+    REQUIRE(variant.as<std::string>() == "4.2");
+    REQUIRE(variant.as<long>() == 4L);
+    REQUIRE(variant.as<unsigned>() == 4U);
+  }
+
+  SECTION("set(0.0)") {
+    variant.set(0.0);
+
+    REQUIRE(variant.as<bool>() == false);
+    REQUIRE(variant.as<long>() == 0L);
+  }
+
+  SECTION("set(false)") {
+    variant.set(false);
+
+    REQUIRE(false == variant.as<bool>());
+    REQUIRE(variant.as<double>() == 0.0);
+    REQUIRE(variant.as<long>() == 0L);
+    REQUIRE(variant.as<std::string>() == "false");
+  }
+
+  SECTION("set(true)") {
+    variant.set(true);
+
+    REQUIRE(variant.as<bool>());
+    REQUIRE(variant.as<double>() == 1.0);
+    REQUIRE(variant.as<long>() == 1L);
+    REQUIRE(variant.as<std::string>() == "true");
+  }
+
+  SECTION("set(42L)") {
+    variant.set(42L);
+
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<double>() == 42.0);
+    REQUIRE(variant.as<std::string>() == "42");
+  }
+
+  SECTION("set(-42L)") {
+    variant.set(-42L);
+
+    REQUIRE(variant.as<double>() == -42.0);
+    REQUIRE(variant.as<std::string>() == "-42");
+  }
+
+  SECTION("set(0L)") {
+    variant.set(0L);
+
+    REQUIRE(variant.as<bool>() == false);
+    REQUIRE(variant.as<double>() == 0.0);
+  }
+
+  SECTION("set(null)") {
+    variant.set(null);
+
+    REQUIRE(variant.as<bool>() == false);
+    REQUIRE(variant.as<double>() == 0.0);
+    REQUIRE(variant.as<long>() == 0L);
+    REQUIRE(variant.as<std::string>() == "null");
+  }
+
+  SECTION("set(\"42\")") {
+    variant.set("42");
+
+    REQUIRE(variant.as<long>() == 42L);
+  }
+
+  SECTION("set(\"hello\")") {
+    variant.set("hello");
+
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<long>() == 0L);
+    REQUIRE(variant.as<const char*>() == std::string("hello"));
+    REQUIRE(variant.as<char*>() == std::string("hello"));
+    REQUIRE(variant.as<std::string>() == std::string("hello"));
+  }
+
+  SECTION("set(std::string(\"4.2\"))") {
+    variant.set(std::string("4.2"));
+
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<long>() == 4L);
+    REQUIRE(variant.as<double>() == 4.2);
+    REQUIRE(variant.as<char*>() == std::string("4.2"));
+    REQUIRE(variant.as<std::string>() == std::string("4.2"));
+  }
+
+  SECTION("set(\"true\")") {
+    variant.set("true");
+
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<int>() == 0);
+  }
+
+  SECTION("set(-1e300)") {
+    variant.set(-1e300);
+
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<double>() == -1e300);
+    REQUIRE(variant.as<float>() < 0);
+    REQUIRE(my::isinf(variant.as<float>()));
+  }
+
+  SECTION("set(1e300)") {
+    variant.set(1e300);
+
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<double>() == 1e300);
+    REQUIRE(variant.as<float>() > 0);
+    REQUIRE(my::isinf(variant.as<float>()));
+  }
+
+  SECTION("set(1e-300)") {
+    variant.set(1e-300);
+
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<double>() == 1e-300);
+    REQUIRE(variant.as<float>() == 0);
+  }
+
+  SECTION("to<JsonObject>()") {
+    JsonObject obj = variant.to<JsonObject>();
+    obj["key"] = "value";
+
+    SECTION("as<bool>()") {
+      REQUIRE(variant.as<bool>() == true);
+    }
+
+    SECTION("as<std::string>()") {
+      REQUIRE(variant.as<std::string>() == std::string("{\"key\":\"value\"}"));
+    }
+
+    SECTION("ObjectAsJsonObject") {
+      JsonObject o = variant.as<JsonObject>();
+      REQUIRE(o.size() == 1);
+      REQUIRE(o["key"] == std::string("value"));
+    }
+  }
+
+  SECTION("to<JsonArray>()") {
+    JsonArray arr = variant.to<JsonArray>();
+    arr.add(4);
+    arr.add(2);
+
+    SECTION("as<bool>()") {
+      REQUIRE(variant.as<bool>() == true);
+    }
+
+    SECTION("as<std::string>()") {
+      REQUIRE(variant.as<std::string>() == std::string("[4,2]"));
+    }
+
+    SECTION("as<JsonArray>()") {
+      JsonArray a = variant.as<JsonArray>();
+      REQUIRE(a.size() == 2);
+      REQUIRE(a[0] == 4);
+      REQUIRE(a[1] == 2);
+    }
+  }
+
+#if ARDUINOJSON_USE_LONG_LONG
+  SECTION("Smallest int64 negative") {
+    variant.set("-9223372036854775808");
+    REQUIRE(variant.as<long long>() == -9223372036854775807 - 1);
+  }
+
+  SECTION("Biggerst int64 positive") {
+    variant.set("9223372036854775807");
+    REQUIRE(variant.as<long long>() == 9223372036854775807);
+  }
+#endif
+
+  SECTION("should work on JsonVariantConst") {
+    variant.set("hello");
+
+    JsonVariantConst cvar = variant;
+
+    REQUIRE(cvar.as<bool>() == true);
+    REQUIRE(cvar.as<long>() == 0L);
+    REQUIRE(cvar.as<const char*>() == std::string("hello"));
+    REQUIRE(cvar.as<char*>() == std::string("hello"));
+    // REQUIRE(cvar.as<std::string>() == std::string("hello"));
+  }
+}

extras/tests/JsonVariant/clear.cpp

@@ -0,0 +1,28 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+
+static const char* null = 0;
+
+TEST_CASE("JsonVariant::clear()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("size goes back to zero") {
+    var.add(42);
+    var.clear();
+
+    REQUIRE(var.size() == 0);
+  }
+
+  SECTION("isNull() return true") {
+    var.add("hello");
+    var.clear();
+
+    REQUIRE(var.isNull() == true);
+  }
+}

extras/tests/JsonVariant/compare.cpp

@@ -0,0 +1,464 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+static const char* null = 0;
+
+template <typename T>
+void checkEquals(T a, T b) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+  variant.set(a);
+
+  REQUIRE(b == variant);
+  REQUIRE(variant == b);
+  REQUIRE(b <= variant);
+  REQUIRE(variant <= b);
+  REQUIRE(b >= variant);
+  REQUIRE(variant >= b);
+
+  REQUIRE_FALSE(b != variant);
+  REQUIRE_FALSE(variant != b);
+  REQUIRE_FALSE(b > variant);
+  REQUIRE_FALSE(variant > b);
+  REQUIRE_FALSE(b < variant);
+  REQUIRE_FALSE(variant < b);
+}
+
+template <typename T>
+void checkGreater(T a, T b) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+  variant.set(a);
+
+  REQUIRE(variant > b);
+  REQUIRE(b < variant);
+  REQUIRE(variant != b);
+  REQUIRE(b != variant);
+
+  REQUIRE_FALSE(variant < b);
+  REQUIRE_FALSE(b > variant);
+  REQUIRE_FALSE(variant == b);
+  REQUIRE_FALSE(b == variant);
+}
+
+template <typename T>
+void checkLower(T a, T b) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+  variant.set(a);
+
+  REQUIRE(variant < b);
+  REQUIRE(b > variant);
+  REQUIRE(variant != b);
+  REQUIRE(b != variant);
+
+  REQUIRE_FALSE(variant > b);
+  REQUIRE_FALSE(b < variant);
+  REQUIRE_FALSE(variant == b);
+  REQUIRE_FALSE(b == variant);
+}
+
+template <typename T>
+void checkComparisons(T low, T mid, T high) {
+  checkEquals(mid, mid);
+  checkGreater(mid, low);
+  checkLower(mid, high);
+}
+
+TEST_CASE("JsonVariant comparisons") {
+  SECTION("Double") {
+    checkComparisons<double>(123.44, 123.45, 123.46);
+  }
+
+  SECTION("Float") {
+    checkComparisons<float>(123.44f, 123.45f, 123.46f);
+  }
+
+  SECTION("SChar") {
+    checkComparisons<signed char>(122, 123, 124);
+  }
+
+  SECTION("SInt") {
+    checkComparisons<signed int>(122, 123, 124);
+  }
+
+  SECTION("SLong") {
+    checkComparisons<signed long>(122L, 123L, 124L);
+  }
+
+  SECTION("SShort") {
+    checkComparisons<signed short>(122, 123, 124);
+  }
+
+  SECTION("UChar") {
+    checkComparisons<unsigned char>(122, 123, 124);
+  }
+
+  SECTION("UInt") {
+    checkComparisons<unsigned int>(122, 123, 124);
+  }
+
+  SECTION("ULong") {
+    checkComparisons<unsigned long>(122L, 123L, 124L);
+  }
+
+  SECTION("UShort") {
+    checkComparisons<unsigned short>(122, 123, 124);
+  }
+
+  SECTION("null") {
+    DynamicJsonDocument doc(4096);
+    JsonVariant variant = doc.to<JsonVariant>();
+    variant.set(null);
+
+    REQUIRE(variant == variant);
+    REQUIRE_FALSE(variant != variant);
+
+    REQUIRE(variant == null);
+    REQUIRE_FALSE(variant != null);
+
+    REQUIRE(variant != "null");
+    REQUIRE_FALSE(variant == "null");
+  }
+
+  SECTION("StringLiteral") {
+    DynamicJsonDocument doc(4096);
+    deserializeJson(doc, "\"hello\"");
+    JsonVariant variant = doc.as<JsonVariant>();
+
+    REQUIRE(variant == variant);
+    REQUIRE_FALSE(variant != variant);
+
+    REQUIRE(variant == "hello");
+    REQUIRE_FALSE(variant != "hello");
+
+    REQUIRE(variant != "world");
+    REQUIRE_FALSE(variant == "world");
+
+    REQUIRE(variant != null);
+    REQUIRE_FALSE(variant == null);
+
+    REQUIRE("hello" == variant);
+    REQUIRE_FALSE("hello" != variant);
+
+    REQUIRE("world" != variant);
+    REQUIRE_FALSE("world" == variant);
+
+    REQUIRE(null != variant);
+    REQUIRE_FALSE(null == variant);
+  }
+
+  SECTION("String") {
+    DynamicJsonDocument doc(4096);
+    JsonVariant variant = doc.to<JsonVariant>();
+    variant.set("hello");
+
+    REQUIRE(variant == variant);
+    REQUIRE_FALSE(variant != variant);
+
+    REQUIRE(variant == std::string("hello"));
+    REQUIRE_FALSE(variant != std::string("hello"));
+
+    REQUIRE(variant != std::string("world"));
+    REQUIRE_FALSE(variant == std::string("world"));
+
+    REQUIRE(variant != null);
+    REQUIRE_FALSE(variant == null);
+
+    REQUIRE(std::string("hello") == variant);
+    REQUIRE_FALSE(std::string("hello") != variant);
+
+    REQUIRE(std::string("world") != variant);
+    REQUIRE_FALSE(std::string("world") == variant);
+
+    REQUIRE(null != variant);
+    REQUIRE_FALSE(null == variant);
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("VLA equals") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    DynamicJsonDocument doc(4096);
+    JsonVariant variant = doc.to<JsonVariant>();
+    variant.set("hello");
+
+    REQUIRE((vla == variant));
+    REQUIRE((variant == vla));
+    REQUIRE_FALSE((vla != variant));
+    REQUIRE_FALSE((variant != vla));
+  }
+
+  SECTION("VLA differs") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    DynamicJsonDocument doc(4096);
+    JsonVariant variant = doc.to<JsonVariant>();
+    variant.set("world");
+
+    REQUIRE((vla != variant));
+    REQUIRE((variant != vla));
+    REQUIRE_FALSE((vla == variant));
+    REQUIRE_FALSE((variant == vla));
+  }
+#endif
+
+  DynamicJsonDocument doc1(4096), doc2(4096), doc3(4096);
+  JsonVariant variant1 = doc1.to<JsonVariant>();
+  JsonVariant variant2 = doc2.to<JsonVariant>();
+  JsonVariant variant3 = doc3.to<JsonVariant>();
+
+  SECTION("Variants containing integers") {
+    variant1.set(42);
+    variant2.set(42);
+    variant3.set(666);
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("Variants containing linked strings") {
+    // create two identical strings at different addresses
+    char hello1[] = "hello";
+    char hello2[] = "hello";
+    REQUIRE(hello1 != hello2);
+
+    variant1.set(hello1);
+    variant2.set(hello2);
+    variant3.set("world");
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("Variants containing owned strings") {
+    variant1.set(std::string("hello"));
+    variant2.set(std::string("hello"));
+    variant3.set(std::string("world"));
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("Variants containing linked raws") {
+    // create two identical strings at different addresses
+    char hello1[] = "hello";
+    char hello2[] = "hello";
+    REQUIRE(hello1 != hello2);
+
+    variant1.set(serialized(hello1));
+    variant2.set(serialized(hello2));
+    variant3.set(serialized("world"));
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("Variants containing owned raws") {
+    variant1.set(serialized(std::string("hello")));
+    variant2.set(serialized(std::string("hello")));
+    variant3.set(serialized(std::string("world")));
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("Variants containing mixed strings (issue #1051)") {
+    variant1.set("hello");
+    variant2.set(std::string("hello"));
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant2 == variant1);
+    REQUIRE_FALSE(variant2 != variant1);
+  }
+
+  SECTION("Variants containing double") {
+    variant1.set(42.0);
+    variant2.set(42.0);
+    variant3.set(666.0);
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("BoolInVariant") {
+    variant1.set(true);
+    variant2.set(true);
+    variant3.set(false);
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("ArrayInVariant") {
+    JsonArray array1 = variant1.to<JsonArray>();
+    JsonArray array2 = variant2.to<JsonArray>();
+
+    array1.add(42);
+    array2.add(42);
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+
+  SECTION("ObjectInVariant") {
+    JsonObject obj1 = variant1.to<JsonObject>();
+    JsonObject obj2 = variant2.to<JsonObject>();
+
+    obj1["hello"] = "world";
+    obj2["hello"] = "world";
+
+    REQUIRE(variant1 == variant2);
+    REQUIRE_FALSE(variant1 != variant2);
+
+    REQUIRE(variant1 != variant3);
+    REQUIRE_FALSE(variant1 == variant3);
+  }
+}
+
+class VariantComparisionFixture {
+ private:
+  StaticJsonDocument<256> doc;
+  JsonVariant variant;
+
+ public:
+  VariantComparisionFixture() : variant(doc.to<JsonVariant>()) {}
+
+ protected:
+  template <typename T>
+  void setValue(const T& value) {
+    variant.set(value);
+  }
+
+  template <typename T>
+  void assertEqualsTo(const T& value) {
+    REQUIRE(variant == value);
+    REQUIRE(value == variant);
+
+    REQUIRE_FALSE(variant != value);
+    REQUIRE_FALSE(value != variant);
+  }
+
+  template <typename T>
+  void assertDiffersFrom(const T& value) {
+    REQUIRE(variant != value);
+    REQUIRE(value != variant);
+
+    REQUIRE_FALSE(variant == value);
+    REQUIRE_FALSE(value == variant);
+  }
+
+  template <typename T>
+  void assertGreaterThan(const T& value) {
+    REQUIRE((variant > value));
+    REQUIRE((variant >= value));
+    REQUIRE(value < variant);
+    REQUIRE(value <= variant);
+
+    REQUIRE_FALSE((variant < value));
+    REQUIRE_FALSE((variant <= value));
+    REQUIRE_FALSE(value > variant);
+    REQUIRE_FALSE(value >= variant);
+  }
+
+  template <typename T>
+  void assertLowerThan(const T& value) {
+    REQUIRE(variant < value);
+    REQUIRE(variant <= value);
+    REQUIRE(value > variant);
+    REQUIRE(value >= variant);
+
+    REQUIRE_FALSE(variant > value);
+    REQUIRE_FALSE(variant >= value);
+    REQUIRE_FALSE(value < variant);
+    REQUIRE_FALSE(value <= variant);
+  }
+};
+
+TEST_CASE_METHOD(VariantComparisionFixture,
+                 "Compare variant with another type") {
+  SECTION("null") {
+    assertDiffersFrom(3);
+    assertDiffersFrom("world");
+  }
+
+  SECTION("string") {
+    setValue("hello");
+    assertEqualsTo("hello");
+    assertDiffersFrom(3);
+    assertDiffersFrom("world");
+    assertGreaterThan("helln");
+    assertLowerThan("hellp");
+  }
+
+  SECTION("positive integer") {
+    setValue(42);
+    assertEqualsTo(42);
+    assertDiffersFrom(43);
+    assertGreaterThan(41);
+    assertLowerThan(43);
+    assertDiffersFrom("world");
+  }
+
+  SECTION("negative integer") {
+    setValue(-42);
+    assertEqualsTo(-42);
+    assertDiffersFrom(42);
+    assertGreaterThan(-43);
+    assertLowerThan(-41);
+    assertDiffersFrom("world");
+  }
+
+  SECTION("double") {
+    setValue(42.0);
+    assertEqualsTo(42.0);
+    assertDiffersFrom(42.1);
+    assertGreaterThan(41.0);
+    assertLowerThan(43.0);
+    assertDiffersFrom("42.0");
+  }
+
+  SECTION("true") {
+    setValue(true);
+    assertEqualsTo(true);
+    assertDiffersFrom(false);
+    assertDiffersFrom(1);
+    assertDiffersFrom("true");
+    assertDiffersFrom(1.0);
+    assertGreaterThan(false);
+  }
+}

extras/tests/JsonVariant/containsKey.cpp

@@ -0,0 +1,28 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+
+static const char* null = 0;
+
+TEST_CASE("JsonVariant::containsKey()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("containsKey(const char*) returns true") {
+    var["hello"] = "world";
+
+    REQUIRE(var.containsKey("hello") == true);
+    REQUIRE(var.containsKey("world") == false);
+  }
+
+  SECTION("containsKey(std::string) returns true") {
+    var["hello"] = "world";
+
+    REQUIRE(var.containsKey(std::string("hello")) == true);
+    REQUIRE(var.containsKey(std::string("world")) == false);
+  }
+}

extras/tests/JsonVariant/copy.cpp

@@ -0,0 +1,86 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant::set(JsonVariant)") {
+  DynamicJsonDocument doc1(4096);
+  DynamicJsonDocument doc2(4096);
+  JsonVariant var1 = doc1.to<JsonVariant>();
+  JsonVariant var2 = doc2.to<JsonVariant>();
+
+  SECTION("stores JsonArray by copy") {
+    JsonArray arr = doc2.to<JsonArray>();
+    JsonObject obj = arr.createNestedObject();
+    obj["hello"] = "world";
+
+    var1.set(arr);
+
+    arr[0] = 666;
+    REQUIRE(var1.as<std::string>() == "[{\"hello\":\"world\"}]");
+  }
+
+  SECTION("stores JsonObject by copy") {
+    JsonObject obj = doc2.to<JsonObject>();
+    JsonArray arr = obj.createNestedArray("value");
+    arr.add(42);
+
+    var1.set(obj);
+
+    obj["value"] = 666;
+    REQUIRE(var1.as<std::string>() == "{\"value\":[42]}");
+  }
+
+  SECTION("stores const char* by reference") {
+    var1.set("hello!!");
+    var2.set(var1);
+
+    REQUIRE(doc1.memoryUsage() == 0);
+    REQUIRE(doc2.memoryUsage() == 0);
+  }
+
+  SECTION("stores char* by copy") {
+    char str[] = "hello!!";
+
+    var1.set(str);
+    var2.set(var1);
+
+    REQUIRE(doc1.memoryUsage() == JSON_STRING_SIZE(8));
+    REQUIRE(doc2.memoryUsage() == JSON_STRING_SIZE(8));
+  }
+
+  SECTION("stores std::string by copy") {
+    var1.set(std::string("hello!!"));
+    var2.set(var1);
+
+    REQUIRE(doc1.memoryUsage() == JSON_STRING_SIZE(8));
+    REQUIRE(doc2.memoryUsage() == JSON_STRING_SIZE(8));
+  }
+
+  SECTION("stores Serialized<const char*> by reference") {
+    var1.set(serialized("hello!!", JSON_STRING_SIZE(8)));
+    var2.set(var1);
+
+    REQUIRE(doc1.memoryUsage() == 0);
+    REQUIRE(doc2.memoryUsage() == 0);
+  }
+
+  SECTION("stores Serialized<char*> by copy") {
+    char str[] = "hello!!";
+    var1.set(serialized(str, 8));
+    var2.set(var1);
+
+    REQUIRE(doc1.memoryUsage() == JSON_STRING_SIZE(8));
+    REQUIRE(doc2.memoryUsage() == JSON_STRING_SIZE(8));
+  }
+
+  SECTION("stores Serialized<std::string> by copy") {
+    var1.set(serialized(std::string("hello!!!")));
+    var2.set(var1);
+
+    REQUIRE(doc1.memoryUsage() == JSON_STRING_SIZE(8));
+    REQUIRE(doc2.memoryUsage() == JSON_STRING_SIZE(8));
+  }
+}

extras/tests/JsonVariant/createNested.cpp

@@ -0,0 +1,88 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+
+static const char* null = 0;
+
+TEST_CASE("JsonVariant::createNestedObject()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("promotes to array") {
+    JsonObject obj = variant.createNestedObject();
+    obj["value"] = 42;
+
+    REQUIRE(variant.is<JsonArray>() == true);
+    REQUIRE(variant[0]["value"] == 42);
+    REQUIRE(obj.isNull() == false);
+  }
+
+  SECTION("works on MemberProxy") {
+    JsonObject obj = variant["items"].createNestedObject();
+    obj["value"] = 42;
+
+    REQUIRE(variant["items"][0]["value"] == 42);
+  }
+}
+
+TEST_CASE("JsonVariant::createNestedArray()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("promotes to array") {
+    JsonArray arr = variant.createNestedArray();
+
+    REQUIRE(variant.is<JsonArray>() == true);
+    REQUIRE(arr.isNull() == false);
+  }
+
+  SECTION("works on MemberProxy") {
+    JsonArray arr = variant["items"].createNestedArray();
+    arr.add(42);
+
+    REQUIRE(variant["items"][0][0] == 42);
+  }
+}
+
+TEST_CASE("JsonVariant::createNestedObject(key)") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("promotes to object") {
+    JsonObject obj = variant.createNestedObject("weather");
+    obj["temp"] = 42;
+
+    REQUIRE(variant.is<JsonObject>() == true);
+    REQUIRE(variant["weather"]["temp"] == 42);
+  }
+
+  SECTION("works on MemberProxy") {
+    JsonObject obj = variant["status"].createNestedObject("weather");
+    obj["temp"] = 42;
+
+    REQUIRE(variant["status"]["weather"]["temp"] == 42);
+  }
+}
+
+TEST_CASE("JsonVariant::createNestedArray(key)") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("promotes to object") {
+    JsonArray arr = variant.createNestedArray("items");
+
+    REQUIRE(variant.is<JsonObject>() == true);
+    REQUIRE(arr.isNull() == false);
+  }
+
+  SECTION("works on MemberProxy") {
+    JsonArray arr = variant["weather"].createNestedArray("temp");
+    arr.add(42);
+
+    REQUIRE(variant["weather"]["temp"][0] == 42);
+  }
+}

extras/tests/JsonVariant/is.cpp

@@ -0,0 +1,162 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+template <typename TVariant>
+void checkIsArray(TVariant var) {
+  REQUIRE(var.template is<JsonArray>());
+
+  REQUIRE_FALSE(var.template is<bool>());
+  REQUIRE_FALSE(var.template is<double>());
+  REQUIRE_FALSE(var.template is<float>());
+  REQUIRE_FALSE(var.template is<int>());
+  REQUIRE_FALSE(var.template is<long>());
+  REQUIRE_FALSE(var.template is<const char *>());
+  REQUIRE_FALSE(var.template is<JsonObject>());
+}
+
+void testArray(JsonArray value) {
+  DynamicJsonDocument doc(4096);
+
+  JsonVariant var = doc.to<JsonVariant>();
+  var.set(value);
+
+  checkIsArray(var);
+
+  JsonVariantConst cvar = var;
+  checkIsArray(cvar);
+}
+
+template <typename TVariant>
+void checkIsBool(TVariant var) {
+  REQUIRE(var.template is<bool>());
+
+  REQUIRE_FALSE(var.template is<double>());
+  REQUIRE_FALSE(var.template is<float>());
+  REQUIRE_FALSE(var.template is<int>());
+  REQUIRE_FALSE(var.template is<long>());
+  REQUIRE_FALSE(var.template is<const char *>());
+  REQUIRE_FALSE(var.template is<JsonArray>());
+  REQUIRE_FALSE(var.template is<JsonObject>());
+}
+
+void testBool(bool value) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+  var.set(value);
+
+  checkIsBool(var);
+  checkIsBool(JsonVariantConst(var));
+}
+
+template <typename TVariant>
+void checkIsFloat(TVariant var) {
+  REQUIRE(var.template is<double>());
+  REQUIRE(var.template is<float>());
+
+  REQUIRE_FALSE(var.template is<bool>());
+  REQUIRE_FALSE(var.template is<int>());
+  REQUIRE_FALSE(var.template is<long>());
+  REQUIRE_FALSE(var.template is<const char *>());
+  REQUIRE_FALSE(var.template is<JsonArray>());
+  REQUIRE_FALSE(var.template is<JsonObject>());
+}
+
+void testFloat(double value) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+  var.set(value);
+
+  checkIsFloat(var);
+  checkIsFloat(JsonVariantConst(var));
+}
+
+template <typename TVariant>
+void checkIsInteger(TVariant var) {
+  REQUIRE(var.template is<long>());
+  REQUIRE(var.template is<int>());
+  REQUIRE(var.template is<float>());
+  REQUIRE(var.template is<double>());
+
+  REQUIRE_FALSE(var.template is<bool>());
+  REQUIRE_FALSE(var.template is<const char *>());
+  REQUIRE_FALSE(var.template is<JsonArray>());
+  REQUIRE_FALSE(var.template is<JsonObject>());
+}
+
+template <typename T>
+void testInteger(T value) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+  var.set(value);
+
+  checkIsInteger(var);
+  checkIsInteger(JsonVariantConst(var));
+}
+
+template <typename TVariant>
+void checkIsString(TVariant var) {
+  REQUIRE(var.template is<const char *>());
+  REQUIRE(var.template is<std::string>());
+
+  REQUIRE_FALSE(var.template is<bool>());
+  REQUIRE_FALSE(var.template is<int>());
+  REQUIRE_FALSE(var.template is<double>());
+  REQUIRE_FALSE(var.template is<float>());
+  REQUIRE_FALSE(var.template is<long>());
+  REQUIRE_FALSE(var.template is<JsonArray>());
+  REQUIRE_FALSE(var.template is<JsonObject>());
+}
+
+void testString(const char *value) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+  var.set(value);
+
+  checkIsString(var);
+  checkIsString(JsonVariantConst(var));
+}
+
+TEST_CASE("JsonVariant::is()") {
+  SECTION("JsonArray") {
+    DynamicJsonDocument doc(4096);
+    JsonArray array = doc.to<JsonArray>();
+    testArray(array);
+  }
+
+  SECTION("bool") {
+    testBool(true);
+    testBool(false);
+  }
+
+  SECTION("double") {
+    testFloat(4.2);
+  }
+
+  SECTION("int") {
+    testInteger(42);
+  }
+
+  SECTION("long") {
+    testInteger(42L);
+  }
+
+  SECTION("string") {
+    testString("42");
+  }
+
+  SECTION("null") {
+    DynamicJsonDocument doc(4096);
+    deserializeJson(doc, "[null]");
+    JsonVariant v = doc[0];
+
+    REQUIRE(v.is<bool>() == false);
+    REQUIRE(v.is<char *>() == false);
+    REQUIRE(v.is<int>() == false);
+    REQUIRE(v.is<std::string>() == false);
+    REQUIRE(v.is<float>() == false);
+  }
+}

extras/tests/JsonVariant/isnull.cpp

@@ -0,0 +1,80 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant::isNull()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("return true when Undefined") {
+    REQUIRE(variant.isNull() == true);
+  }
+
+  SECTION("return false when Integer") {
+    variant.set(42);
+
+    REQUIRE(variant.isNull() == false);
+  }
+
+  SECTION("return false when EmptyArray") {
+    DynamicJsonDocument doc2(4096);
+    JsonArray array = doc2.to<JsonArray>();
+
+    variant.set(array);
+    REQUIRE(variant.isNull() == false);
+  }
+
+  SECTION("return false when EmptyObject") {
+    DynamicJsonDocument doc2(4096);
+    JsonObject obj = doc2.to<JsonObject>();
+
+    variant.set(obj);
+    REQUIRE(variant.isNull() == false);
+  }
+
+  SECTION("return true after set(JsonArray())") {
+    variant.set(JsonArray());
+    REQUIRE(variant.isNull() == true);
+  }
+
+  SECTION("return true after set(JsonObject())") {
+    variant.set(JsonObject());
+    REQUIRE(variant.isNull() == true);
+  }
+
+  SECTION("return false after set('hello')") {
+    variant.set("hello");
+    REQUIRE(variant.isNull() == false);
+  }
+
+  SECTION("return true after set((char*)0)") {
+    variant.set(static_cast<char*>(0));
+    REQUIRE(variant.isNull() == true);
+  }
+
+  SECTION("return true after set((const char*)0)") {
+    variant.set(static_cast<const char*>(0));
+    REQUIRE(variant.isNull() == true);
+  }
+
+  SECTION("return true after set(serialized((char*)0))") {
+    variant.set(serialized(static_cast<char*>(0)));
+    REQUIRE(variant.isNull() == true);
+  }
+
+  SECTION("return true after set(serialized((const char*)0))") {
+    variant.set(serialized(static_cast<const char*>(0)));
+    REQUIRE(variant.isNull() == true);
+  }
+
+  SECTION("works with JsonVariantConst") {
+    variant.set(42);
+
+    JsonVariantConst cvar = variant;
+
+    REQUIRE(cvar.isNull() == false);
+  }
+}

extras/tests/JsonVariant/memoryUsage.cpp

@@ -0,0 +1,39 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+#include <string>
+
+TEST_CASE("JsonVariant::memoryUsage()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("returns 0 if uninitialized") {
+    JsonVariant unitialized;
+    REQUIRE(unitialized.memoryUsage() == 0);
+  }
+
+  SECTION("returns size of object") {
+    JsonObject obj = var.to<JsonObject>();
+    obj["hello"] = 42;
+    REQUIRE(var.memoryUsage() == JSON_OBJECT_SIZE(1));
+  }
+
+  SECTION("returns size of array") {
+    JsonArray arr = var.to<JsonArray>();
+    arr.add(42);
+    REQUIRE(var.memoryUsage() == JSON_ARRAY_SIZE(1));
+  }
+
+  SECTION("returns size of owned string") {
+    var.set(std::string("hello"));
+    REQUIRE(var.memoryUsage() == 6);
+  }
+
+  SECTION("returns size of owned raw") {
+    var.set(serialized(std::string("hello")));
+    REQUIRE(var.memoryUsage() == 5);
+  }
+}

extras/tests/JsonVariant/misc.cpp

@@ -0,0 +1,50 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant from JsonArray") {
+  SECTION("JsonArray is null") {
+    JsonArray arr;
+    JsonVariant v = arr;
+    REQUIRE(v.isNull() == true);
+  }
+
+  SECTION("JsonArray is not null") {
+    DynamicJsonDocument doc(4096);
+    JsonArray arr = doc.to<JsonArray>();
+    arr.add(12);
+    arr.add(34);
+
+    JsonVariant v = arr;
+
+    REQUIRE(v.is<JsonArray>() == true);
+    REQUIRE(v.size() == 2);
+    REQUIRE(v[0] == 12);
+    REQUIRE(v[1] == 34);
+  }
+}
+
+TEST_CASE("JsonVariant from JsonObject") {
+  SECTION("JsonObject is null") {
+    JsonObject obj;
+    JsonVariant v = obj;
+    REQUIRE(v.isNull() == true);
+  }
+
+  SECTION("JsonObject is not null") {
+    DynamicJsonDocument doc(4096);
+    JsonObject obj = doc.to<JsonObject>();
+    obj["a"] = 12;
+    obj["b"] = 34;
+
+    JsonVariant v = obj;
+
+    REQUIRE(v.is<JsonObject>() == true);
+    REQUIRE(v.size() == 2);
+    REQUIRE(v["a"] == 12);
+    REQUIRE(v["b"] == 34);
+  }
+}

extras/tests/JsonVariant/nesting.cpp

@@ -0,0 +1,31 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant::nesting()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("return 0 if uninitialized") {
+    JsonVariant unitialized;
+    REQUIRE(unitialized.nesting() == 0);
+  }
+
+  SECTION("returns 0 for string") {
+    var.set("hello");
+    REQUIRE(var.nesting() == 0);
+  }
+
+  SECTION("returns 1 for empty object") {
+    var.to<JsonObject>();
+    REQUIRE(var.nesting() == 1);
+  }
+
+  SECTION("returns 1 for empty array") {
+    var.to<JsonArray>();
+    REQUIRE(var.nesting() == 1);
+  }
+}

extras/tests/JsonVariant/or.cpp

@@ -0,0 +1,96 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant::operator|()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("undefined") {
+    SECTION("undefined | const char*") {
+      std::string result = variant | "default";
+      REQUIRE(result == "default");
+    }
+
+    SECTION("undefined | int") {
+      int result = variant | 42;
+      REQUIRE(result == 42);
+    }
+
+    SECTION("undefined | bool") {
+      bool result = variant | true;
+      REQUIRE(result == true);
+    }
+  }
+
+  SECTION("null") {
+    variant.set(static_cast<const char*>(0));
+
+    SECTION("null | const char*") {
+      std::string result = variant | "default";
+      REQUIRE(result == "default");
+    }
+
+    SECTION("null | int") {
+      int result = variant | 42;
+      REQUIRE(result == 42);
+    }
+
+    SECTION("null | bool") {
+      bool result = variant | true;
+      REQUIRE(result == true);
+    }
+  }
+
+  SECTION("int | const char*") {
+    variant.set(42);
+    std::string result = variant | "default";
+    REQUIRE(result == "default");
+  }
+
+  SECTION("int | uint8_t (out of range)") {
+    variant.set(666);
+    uint8_t result = variant | static_cast<uint8_t>(42);
+    REQUIRE(result == 42);
+  }
+
+  SECTION("int | int") {
+    variant.set(0);
+    int result = variant | 666;
+    REQUIRE(result == 0);
+  }
+
+  SECTION("double | int") {
+    // NOTE: changed the behavior to fix #981
+    variant.set(666.0);
+    int result = variant | 42;
+    REQUIRE(result == 42);
+  }
+
+  SECTION("bool | bool") {
+    variant.set(false);
+    bool result = variant | true;
+    REQUIRE(result == false);
+  }
+
+  SECTION("int | bool") {
+    variant.set(0);
+    bool result = variant | true;
+    REQUIRE(result == true);
+  }
+
+  SECTION("const char* | const char*") {
+    variant.set("not default");
+    std::string result = variant | "default";
+    REQUIRE(result == "not default");
+  }
+
+  SECTION("const char* | int") {
+    variant.set("not default");
+    int result = variant | 42;
+    REQUIRE(result == 42);
+  }
+}

extras/tests/JsonVariant/overflow.cpp

@@ -0,0 +1,72 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+template <typename TOut, typename TIn>
+void shouldBeOk(TIn value) {
+  StaticJsonDocument<1> doc;
+  JsonVariant var = doc.to<JsonVariant>();
+  var.set(value);
+  REQUIRE(var.as<TOut>() == TOut(value));
+}
+
+template <typename TOut, typename TIn>
+void shouldOverflow(TIn value) {
+  StaticJsonDocument<1> doc;
+  JsonVariant var = doc.to<JsonVariant>();
+  var.set(value);
+  REQUIRE(var.as<TOut>() == 0);
+  REQUIRE(var.is<TOut>() == false);
+}
+
+TEST_CASE("Handle integer overflow in stored integer") {
+  SECTION("int8_t") {
+    // ok
+    shouldBeOk<int8_t>(-128);
+    shouldBeOk<int8_t>(42.0);
+    shouldBeOk<int8_t>(127);
+
+    // too low
+    shouldOverflow<int8_t>(-128.1);
+    shouldOverflow<int8_t>(-129);
+
+    // too high
+    shouldOverflow<int8_t>(128);
+    shouldOverflow<int8_t>(127.1);
+  }
+
+  SECTION("int16_t") {
+    // ok
+    shouldBeOk<int16_t>(-32768);
+    shouldBeOk<int16_t>(-32767.9);
+    shouldBeOk<int16_t>(32766.9);
+    shouldBeOk<int16_t>(32767);
+
+    // too low
+    shouldOverflow<int16_t>(-32768.1);
+    shouldOverflow<int16_t>(-32769);
+
+    // too high
+    shouldOverflow<int16_t>(32767.1);
+    shouldOverflow<int16_t>(32768);
+  }
+
+  SECTION("uint8_t") {
+    // ok
+    shouldBeOk<uint8_t>(1);
+    shouldBeOk<uint8_t>(42.0);
+    shouldBeOk<uint8_t>(255);
+
+    // too low
+    shouldOverflow<uint8_t>(-1);
+    shouldOverflow<uint8_t>(-0.1);
+
+    // to high
+    shouldOverflow<uint8_t>(255.1);
+    shouldOverflow<uint8_t>(256);
+    shouldOverflow<uint8_t>(257);
+  }
+}

extras/tests/JsonVariant/remove.cpp

@@ -0,0 +1,42 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+
+static const char* null = 0;
+
+TEST_CASE("JsonVariant::remove()") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("remove(int)") {
+    var.add(1);
+    var.add(2);
+    var.add(3);
+
+    var.remove(1);
+
+    REQUIRE(var.as<std::string>() == "[1,3]");
+  }
+
+  SECTION("remove(const char *)") {
+    var["a"] = 1;
+    var["b"] = 2;
+
+    var.remove("a");
+
+    REQUIRE(var.as<std::string>() == "{\"b\":2}");
+  }
+
+  SECTION("remove(std::string)") {
+    var["a"] = 1;
+    var["b"] = 2;
+
+    var.remove(std::string("b"));
+
+    REQUIRE(var.as<std::string>() == "{\"a\":1}");
+  }
+}

extras/tests/JsonVariant/set.cpp

@@ -0,0 +1,126 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant and strings") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  SECTION("stores const char* by reference") {
+    char str[16];
+
+    strcpy(str, "hello");
+    variant.set(static_cast<const char *>(str));
+    strcpy(str, "world");
+
+    REQUIRE(variant == "world");
+  }
+
+  SECTION("stores char* by copy") {
+    char str[16];
+
+    strcpy(str, "hello");
+    variant.set(str);
+    strcpy(str, "world");
+
+    REQUIRE(variant == "hello");
+  }
+
+  SECTION("stores unsigned char* by copy") {
+    char str[16];
+
+    strcpy(str, "hello");
+    variant.set(reinterpret_cast<unsigned char *>(str));
+    strcpy(str, "world");
+
+    REQUIRE(variant == "hello");
+  }
+
+  SECTION("stores signed char* by copy") {
+    char str[16];
+
+    strcpy(str, "hello");
+    variant.set(reinterpret_cast<signed char *>(str));
+    strcpy(str, "world");
+
+    REQUIRE(variant == "hello");
+  }
+
+#ifdef HAS_VARIABLE_LENGTH_ARRAY
+  SECTION("stores VLA by copy") {
+    int n = 16;
+    char str[n];
+
+    strcpy(str, "hello");
+    variant.set(str);
+    strcpy(str, "world");
+
+    REQUIRE(variant == "hello");
+  }
+#endif
+
+  SECTION("stores std::string by copy") {
+    std::string str;
+
+    str = "hello";
+    variant.set(str);
+    str.replace(0, 5, "world");
+
+    REQUIRE(variant == "hello");
+  }
+
+  SECTION("stores static JsonString by reference") {
+    char str[16];
+
+    strcpy(str, "hello");
+    variant.set(JsonString(str, true));
+    strcpy(str, "world");
+
+    REQUIRE(variant == "hello");
+  }
+
+  SECTION("stores non-static JsonString by copy") {
+    char str[16];
+
+    strcpy(str, "hello");
+    variant.set(JsonString(str, false));
+    strcpy(str, "world");
+
+    REQUIRE(variant == "hello");
+  }
+}
+
+TEST_CASE("JsonVariant with not enough memory") {
+  StaticJsonDocument<1> doc;
+
+  JsonVariant v = doc.to<JsonVariant>();
+
+  SECTION("std::string") {
+    v.set(std::string("hello world!!"));
+    REQUIRE(v.isNull());
+  }
+
+  SECTION("Serialized<std::string>") {
+    v.set(serialized(std::string("hello world!!")));
+    REQUIRE(v.isNull());
+  }
+}
+
+TEST_CASE("JsonVariant::set(DynamicJsonDocument)") {
+  DynamicJsonDocument doc1(1024);
+  doc1["hello"] = "world";
+
+  DynamicJsonDocument doc2(1024);
+  JsonVariant v = doc2.to<JsonVariant>();
+
+  // Should copy the doc
+  v.set(doc1);
+  doc1.clear();
+
+  std::string json;
+  serializeJson(doc2, json);
+  REQUIRE(json == "{\"hello\":\"world\"}");
+}

extras/tests/JsonVariant/subscript.cpp

@@ -0,0 +1,195 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant::operator[]") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+
+  SECTION("The JsonVariant is undefined") {
+    REQUIRE(0 == var.size());
+    REQUIRE(var["0"].isNull());
+    REQUIRE(var[0].isNull());
+  }
+
+  SECTION("The JsonVariant is a string") {
+    var.set("hello world");
+    REQUIRE(0 == var.size());
+    REQUIRE(var["0"].isNull());
+    REQUIRE(var[0].isNull());
+  }
+
+  SECTION("The JsonVariant is a JsonArray") {
+    JsonArray array = var.to<JsonArray>();
+
+    SECTION("get value") {
+      array.add("element at index 0");
+      array.add("element at index 1");
+
+      REQUIRE(2 == var.size());
+      var[0].as<std::string>();
+      // REQUIRE(std::string("element at index 0") == );
+      REQUIRE(std::string("element at index 1") == var[1]);
+      REQUIRE(std::string("element at index 0") ==
+              var[static_cast<unsigned char>(0)]);  // issue #381
+      REQUIRE(var[666].isNull());
+      REQUIRE(var[3].isNull());
+      REQUIRE(var["0"].isNull());
+    }
+
+    SECTION("set value") {
+      array.add("hello");
+
+      var[0] = "world";
+
+      REQUIRE(1 == var.size());
+      REQUIRE(std::string("world") == var[0]);
+    }
+
+    SECTION("set value in a nested object") {
+      array.createNestedObject();
+
+      var[0]["hello"] = "world";
+
+      REQUIRE(1 == var.size());
+      REQUIRE(1 == var[0].size());
+      REQUIRE(std::string("world") == var[0]["hello"]);
+    }
+  }
+
+  SECTION("The JsonVariant is a JsonObject") {
+    JsonObject object = var.to<JsonObject>();
+
+    SECTION("get value") {
+      object["a"] = "element at key \"a\"";
+      object["b"] = "element at key \"b\"";
+
+      REQUIRE(2 == var.size());
+      REQUIRE(std::string("element at key \"a\"") == var["a"]);
+      REQUIRE(std::string("element at key \"b\"") == var["b"]);
+      REQUIRE(var["c"].isNull());
+      REQUIRE(var[0].isNull());
+    }
+
+    SECTION("set value, key is a const char*") {
+      var["hello"] = "world";
+
+      REQUIRE(1 == var.size());
+      REQUIRE(std::string("world") == var["hello"]);
+    }
+
+    SECTION("set value, key is a char[]") {
+      char key[] = "hello";
+      var[key] = "world";
+      key[0] = '!';  // make sure the key is duplicated
+
+      REQUIRE(1 == var.size());
+      REQUIRE(std::string("world") == var["hello"]);
+    }
+
+    SECTION("var[key].to<JsonArray>()") {
+      JsonArray arr = var["hello"].to<JsonArray>();
+      REQUIRE(arr.isNull() == false);
+    }
+  }
+
+#if defined(HAS_VARIABLE_LENGTH_ARRAY) && \
+    !defined(SUBSCRIPT_CONFLICTS_WITH_BUILTIN_OPERATOR)
+  SECTION("key is a VLA") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    deserializeJson(doc, "{\"hello\":\"world\"}");
+    JsonVariant variant = doc.as<JsonVariant>();
+
+    REQUIRE(std::string("world") == variant[vla]);
+  }
+
+  SECTION("key is a VLA, const JsonVariant") {
+    int i = 16;
+    char vla[i];
+    strcpy(vla, "hello");
+
+    deserializeJson(doc, "{\"hello\":\"world\"}");
+    const JsonVariant variant = doc.as<JsonVariant>();
+
+    REQUIRE(std::string("world") == variant[vla]);
+  }
+#endif
+}
+
+TEST_CASE("JsonVariantConst::operator[]") {
+  DynamicJsonDocument doc(4096);
+  JsonVariant var = doc.to<JsonVariant>();
+  JsonVariantConst cvar = var;
+
+  SECTION("The JsonVariant is undefined") {
+    REQUIRE(0 == cvar.size());
+    REQUIRE(cvar["0"].isNull());
+    REQUIRE(cvar[0].isNull());
+  }
+
+  SECTION("The JsonVariant is a string") {
+    var.set("hello world");
+    REQUIRE(0 == cvar.size());
+    REQUIRE(cvar["0"].isNull());
+    REQUIRE(cvar[0].isNull());
+  }
+
+  SECTION("The JsonVariant is a JsonArray") {
+    JsonArray array = var.to<JsonArray>();
+
+    SECTION("get value") {
+      array.add("element at index 0");
+      array.add("element at index 1");
+
+      REQUIRE(2 == cvar.size());
+      REQUIRE(std::string("element at index 0") == cvar[0]);
+      REQUIRE(std::string("element at index 1") == cvar[1]);
+      REQUIRE(std::string("element at index 0") ==
+              var[static_cast<unsigned char>(0)]);  // issue #381
+      REQUIRE(cvar[666].isNull());
+      REQUIRE(cvar[3].isNull());
+      REQUIRE(cvar["0"].isNull());
+    }
+  }
+
+  SECTION("The JsonVariant is a JsonObject") {
+    JsonObject object = var.to<JsonObject>();
+
+    SECTION("get value") {
+      object["a"] = "element at key \"a\"";
+      object["b"] = "element at key \"b\"";
+
+      REQUIRE(2 == cvar.size());
+      REQUIRE(std::string("element at key \"a\"") == cvar["a"]);
+      REQUIRE(std::string("element at key \"b\"") == cvar["b"]);
+      REQUIRE(cvar["c"].isNull());
+      REQUIRE(cvar[0].isNull());
+    }
+  }
+
+  SECTION("Auto promote null JsonVariant to JsonObject") {
+    var["hello"] = "world";
+
+    REQUIRE(var.is<JsonObject>() == true);
+  }
+
+  SECTION("Don't auto promote non-null JsonVariant to JsonObject") {
+    var.set(42);
+    var["hello"] = "world";
+
+    REQUIRE(var.is<JsonObject>() == false);
+  }
+
+  SECTION("Don't auto promote null JsonVariant to JsonObject when reading") {
+    const char* value = var["hello"];
+
+    REQUIRE(var.is<JsonObject>() == false);
+    REQUIRE(value == 0);
+  }
+}

extras/tests/JsonVariant/types.cpp

@@ -0,0 +1,140 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <stdint.h>
+#include <catch.hpp>
+#include <limits>
+
+template <typename T>
+void checkValue(T expected) {
+  DynamicJsonDocument doc(4096);
+  JsonVariant variant = doc.to<JsonVariant>();
+
+  variant.set(expected);
+  REQUIRE(expected == variant.as<T>());
+}
+
+template <typename T>
+void checkReference(T &expected) {
+  JsonVariant variant = expected;
+  REQUIRE(expected == variant.as<T &>());
+}
+
+template <typename T>
+void checkNumericType() {
+  DynamicJsonDocument docMin(4096), docMax(4096);
+  JsonVariant variantMin = docMin.to<JsonVariant>();
+  JsonVariant variantMax = docMax.to<JsonVariant>();
+
+  T min = std::numeric_limits<T>::min();
+  T max = std::numeric_limits<T>::max();
+
+  variantMin.set(min);
+  variantMax.set(max);
+
+  REQUIRE(min == variantMin.as<T>());
+  REQUIRE(max == variantMax.as<T>());
+}
+
+TEST_CASE("JsonVariant set()/get()") {
+#if ARDUINOJSON_USE_LONG_LONG
+  SECTION("SizeOfJsonInteger") {
+    REQUIRE(8 == sizeof(JsonInteger));
+  }
+#endif
+
+  SECTION("Null") {
+    checkValue<const char *>(NULL);
+  }
+  SECTION("const char*") {
+    checkValue<const char *>("hello");
+  }
+  SECTION("std::string") {
+    checkValue<std::string>("hello");
+  }
+
+  SECTION("False") {
+    checkValue<bool>(false);
+  }
+  SECTION("True") {
+    checkValue<bool>(true);
+  }
+
+  SECTION("Double") {
+    checkNumericType<double>();
+  }
+  SECTION("Float") {
+    checkNumericType<float>();
+  }
+  SECTION("Char") {
+    checkNumericType<char>();
+  }
+  SECTION("SChar") {
+    checkNumericType<signed char>();
+  }
+  SECTION("SInt") {
+    checkNumericType<signed int>();
+  }
+  SECTION("SLong") {
+    checkNumericType<signed long>();
+  }
+  SECTION("SShort") {
+    checkNumericType<signed short>();
+  }
+  SECTION("UChar") {
+    checkNumericType<unsigned char>();
+  }
+  SECTION("UInt") {
+    checkNumericType<unsigned int>();
+  }
+  SECTION("ULong") {
+    checkNumericType<unsigned long>();
+  }
+  SECTION("UShort") {
+    checkNumericType<unsigned short>();
+  }
+#if ARDUINOJSON_USE_LONG_LONG
+  SECTION("LongLong") {
+    checkNumericType<unsigned long long>();
+  }
+  SECTION("ULongLong") {
+    checkNumericType<unsigned long long>();
+  }
+#endif
+
+  SECTION("Int8") {
+    checkNumericType<int8_t>();
+  }
+  SECTION("Uint8") {
+    checkNumericType<uint8_t>();
+  }
+  SECTION("Int16") {
+    checkNumericType<int16_t>();
+  }
+  SECTION("Uint16") {
+    checkNumericType<uint16_t>();
+  }
+  SECTION("Int32") {
+    checkNumericType<int32_t>();
+  }
+  SECTION("Uint32") {
+    checkNumericType<uint32_t>();
+  }
+#if ARDUINOJSON_USE_LONG_LONG
+  SECTION("Int64") {
+    checkNumericType<int64_t>();
+  }
+  SECTION("Uint64") {
+    checkNumericType<uint64_t>();
+  }
+#endif
+
+  SECTION("CanStoreObject") {
+    DynamicJsonDocument doc(4096);
+    JsonObject object = doc.to<JsonObject>();
+
+    checkValue<JsonObject>(object);
+  }
+}

extras/tests/JsonVariant/undefined.cpp

@@ -0,0 +1,70 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+TEST_CASE("JsonVariant undefined") {
+  JsonVariant variant;
+
+  SECTION("as<T>()") {
+    SECTION("long") {
+      REQUIRE(variant.as<long>() == 0);
+    }
+
+    SECTION("unsigned") {
+      REQUIRE(variant.as<unsigned>() == 0);
+    }
+
+    SECTION("char*") {
+      REQUIRE(variant.as<char*>() == 0);
+    }
+
+    SECTION("double") {
+      REQUIRE(variant.as<double>() == 0);
+    }
+
+    SECTION("bool") {
+      REQUIRE(variant.as<bool>() == false);
+    }
+
+    SECTION("JsonArray") {
+      REQUIRE(variant.as<JsonArray>().isNull());
+    }
+
+    SECTION("JsonObject") {
+      REQUIRE(variant.as<JsonObject>().isNull());
+    }
+  }
+
+  SECTION("is<T>()") {
+    SECTION("long") {
+      REQUIRE(variant.is<long>() == false);
+    }
+
+    SECTION("unsigned") {
+      REQUIRE(variant.is<unsigned>() == false);
+    }
+
+    SECTION("char*") {
+      REQUIRE(variant.is<char*>() == false);
+    }
+
+    SECTION("double") {
+      REQUIRE(variant.is<double>() == false);
+    }
+
+    SECTION("bool") {
+      REQUIRE(variant.is<bool>() == false);
+    }
+
+    SECTION("JsonArray") {
+      REQUIRE(variant.is<JsonArray>() == false);
+    }
+
+    SECTION("JsonObject") {
+      REQUIRE(variant.is<JsonObject>() == false);
+    }
+  }
+}

extras/tests/MemberProxy/CMakeLists.txt

@@ -0,0 +1,17 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2019
+# MIT License
+
+add_executable(MemberProxyTests
+	add.cpp
+	clear.cpp
+	compare.cpp
+	containsKey.cpp
+	remove.cpp
+	set.cpp
+	size.cpp
+	subscript.cpp
+)
+
+target_link_libraries(MemberProxyTests catch)
+add_test(MemberProxy MemberProxyTests)

extras/tests/MemberProxy/add.cpp

@@ -0,0 +1,25 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("MemberProxy::add()") {
+  DynamicJsonDocument doc(4096);
+  MemberProxy<JsonDocument&, const char*> mp = doc["hello"];
+
+  SECTION("add(int)") {
+    mp.add(42);
+
+    REQUIRE(doc.as<std::string>() == "{\"hello\":[42]}");
+  }
+
+  SECTION("add(const char*)") {
+    mp.add("world");
+
+    REQUIRE(doc.as<std::string>() == "{\"hello\":[\"world\"]}");
+  }
+}

extras/tests/MemberProxy/clear.cpp

@@ -0,0 +1,27 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2019
+// MIT License
+
+#include <ArduinoJson.h>
+#include <catch.hpp>
+
+using namespace ARDUINOJSON_NAMESPACE;
+
+TEST_CASE("MemberProxy::clear()") {
+  DynamicJsonDocument doc(4096);
+  MemberProxy<JsonDocument&, const char*> mp = doc["hello"];
+
+  SECTION("size goes back to zero") {
+    mp.add(42);
+    mp.clear();
+
+    REQUIRE(mp.size() == 0);
+  }
+
+  SECTION("isNull() return true") {
+    mp.add("hello");
+    mp.clear();
+
+    REQUIRE(mp.isNull() == true);
+  }
+}