Introduce support for some common D-Bus annotations (#30)

* Add ability to declare property behavior on PropertyChanged signal

* Add support for Method.NoReply annotation (WIP)

* Add support for common annotations/flags

test/integrationtests/TestingAdaptor.h

@@ -29,6 +29,7 @@
 #include "adaptor-glue.h"
 #include <thread>
 #include <chrono>
+#include <atomic>
 
 class TestingAdaptor : public sdbus::Interfaces<testing_adaptor>
 {
@@ -38,6 +39,10 @@ public:
 
     virtual ~TestingAdaptor() { }
 
+    bool wasMultiplyCalled() const { return m_multiplyCalled; }
+    double getMultiplyResult() const { return m_multiplyResult; }
+    bool wasThrowErrorCalled() const { return m_throwErrorCalled; }
+
 protected:
 
     void noArgNoReturn() const { }
@@ -48,6 +53,12 @@ protected:
 
     double multiply(const int64_t& a, const double& b) const { return a * b; }
 
+    void multiplyWithNoReply(const int64_t& a, const double& b) const
+    {
+        m_multiplyResult = a * b;
+        m_multiplyCalled = true;
+    }
+
     std::vector<int16_t> getInts16FromStruct(const sdbus::Struct<uint8_t, int16_t, double, std::string, std::vector<int16_t>>& x) const
     {
         std::vector<int16_t> res{x.get<1>()};
@@ -154,6 +165,12 @@ protected:
         };
     }
 
+    void throwError() const
+    {
+        m_throwErrorCalled = true;
+        throw sdbus::createError(1, "A test error occurred");
+    }
+
     std::string state() { return STRING_VALUE; }
     uint32_t action() { return m_action; }
     void action(const uint32_t& value) { m_action = value; }
@@ -164,6 +181,10 @@ private:
     uint32_t m_action;
     bool m_blocking;
 
+    // For dont-expect-reply method call verifications
+    mutable std::atomic<bool> m_multiplyCalled{};
+    mutable double m_multiplyResult{};
+    mutable std::atomic<bool> m_throwErrorCalled{};
 };