Add writeOnChange testcase

extras/test/CMakeLists.txt

@@ -42,6 +42,7 @@ set(TEST_SRCS
   src/test_readOnly.cpp
   src/test_writeOnly.cpp
   src/test_writeOnDemand.cpp
+  src/test_writeOnChange.cpp
 )
 
 set(TEST_UTIL_SRCS

extras/test/src/test_writeOnChange.cpp

@@ -0,0 +1,33 @@
+/*
+   Copyright (c) 2019 Arduino.  All rights reserved.
+*/
+
+/**************************************************************************************
+   INCLUDE
+ **************************************************************************************/
+
+#include <catch.hpp>
+
+#include <util/CBORTestUtil.h>
+
+#include <CBORDecoder.h>
+#include <PropertyContainer.h>
+
+/**************************************************************************************
+   TEST CODE
+ **************************************************************************************/
+
+SCENARIO("An Arduino cloud property is marked 'write on change'", "[ArduinoCloudThing::decode]")
+{
+  PropertyContainer property_container;
+
+  CloudInt test = 0;
+  addPropertyToContainer(property_container, test, "test", Permission::ReadWrite).writeOnChange();
+
+  /* [{0: "test", 2: 7}] = 81 A2 00 64 74 65 73 74 02 07 */
+  uint8_t const payload[] = {0x81, 0xA2, 0x00, 0x64, 0x74, 0x65, 0x73, 0x74, 0x02, 0x07};
+  int const payload_length = sizeof(payload) / sizeof(uint8_t);
+  CBORDecoder::decode(property_container, payload, payload_length);
+
+  REQUIRE(test == 7);
+}