Added overflow handling in JsonVariant::as<T>() and JsonVariant::is<T>()

test/JsonVariant/CMakeLists.txt

@@ -15,6 +15,7 @@ add_executable(JsonVariantTests
 	misc.cpp
 	nesting.cpp
 	or.cpp
+	overflow.cpp
 	remove.cpp
 	set.cpp
 	subscript.cpp

test/JsonVariant/as.cpp

@@ -6,6 +6,10 @@
 #include <stdint.h>
 #include <catch.hpp>
 
+namespace my {
+using ARDUINOJSON_NAMESPACE::isinf;
+}  // namespace my
+
 static const char* null = 0;
 
 TEST_CASE("JsonVariant::as()") {
@@ -94,7 +98,6 @@ TEST_CASE("JsonVariant::as()") {
   SECTION("set(\"42\")") {
     variant.set("42");
 
-    REQUIRE(variant.as<bool>());
     REQUIRE(variant.as<long>() == 42L);
   }
 
@@ -111,7 +114,6 @@ TEST_CASE("JsonVariant::as()") {
   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"));
@@ -121,8 +123,31 @@ TEST_CASE("JsonVariant::as()") {
   SECTION("set(\"true\")") {
     variant.set("true");
 
-    REQUIRE(variant.as<bool>());
-    REQUIRE(variant.as<long>() == 1L);
+    REQUIRE(variant.as<bool>() == true);
+    REQUIRE(variant.as<int>() == 0);
+  }
+
+  SECTION("set(-1e300)") {
+    variant.set(-1e300);
+
+    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<double>() == 1e300);
+    REQUIRE(variant.as<float>() > 0);
+    REQUIRE(my::isinf(variant.as<float>()));
+  }
+
+  SECTION("set(1e300)") {
+    variant.set(1e-300);
+
+    REQUIRE(variant.as<double>() == 1e-300);
+    REQUIRE(variant.as<float>() == 0);
   }
 
   SECTION("to<JsonObject>()") {

test/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);
+  }
+}