chore: release version v2.2.0

* test: add Variant move test

* fix: provide signature_of<_T&&>

Provide signature_of specialization for rvalue references resp.
allow when forwarding references resolve to rvalue references

signature_of<_T&&> is needed e.g. for std::map::try_emplace() when the
emplaced sdbus:: type is passed as rvalue reference, otherwise the
static_assert "Unsupported D-Bus type ..." would trigger

See https://github.com/Kistler-Group/sdbus-cpp/issues/513#issuecomment-3429733769
for an elaborate explanation

Signed-off-by: Simon Braunschmidt <simon.braunschmidt@iba-group.com>

---------

Signed-off-by: Simon Braunschmidt <simon.braunschmidt@iba-group.com>
Co-authored-by: Stanislav Angelovic <stanislav.angelovic.ext@siemens.com>

CMakeLists.txt

@@ -4,7 +4,7 @@
 
 cmake_minimum_required(VERSION 3.14)
 
-project(sdbus-c++ VERSION 2.1.0 LANGUAGES CXX C)
+project(sdbus-c++ VERSION 2.2.0 LANGUAGES CXX C)
 
 include(GNUInstallDirs) # Installation directories for `install` command and pkgconfig file
 

ChangeLog

@@ -301,3 +301,13 @@ v2.1.0
 - Change googletest to default version 1.14.0
 - Add version parameter to the xml2cpp codegen tool
 - A few other internal refactorings and improvements
+
+v2.2.0
+- Add createLightWeightProxy() overload for convenience
+- Add cookie-related API to Message class
+- Add async overloads of GetManagedObjects() function
+- Add signature_of specialization for r-value references
+- Create a valid sdbus::Error even when errno is invalid or zero
+- Fix the return type of some slot-returning functions
+- Fix annotation generation in xml2cpp tool
+- A few other, mainly CI related updates

include/sdbus-c++/Error.h

@@ -64,7 +64,7 @@ namespace sdbus {
         }
 
         Error(Name name, std::string message)
-            : std::runtime_error("[" + name + "] " + message)
+            : std::runtime_error(!message.empty() ? "[" + name + "] " + message : "[" + name + "]")
             , name_(std::move(name))
             , message_(std::move(message))
         {
@@ -90,7 +90,7 @@ namespace sdbus {
         std::string message_;
     };
 
-    Error createError(int errNo, std::string customMsg);
+    Error createError(int errNo, std::string customMsg = {});
 
     inline const Error::Name SDBUSCPP_ERROR_NAME{"org.sdbuscpp.Error"};
 }

include/sdbus-c++/TypeTraits.h

@@ -151,6 +151,10 @@ namespace sdbus {
     struct signature_of<_T&> : signature_of<_T>
     {};
 
+    template <typename _T>
+    struct signature_of<_T&&> : signature_of<_T>
+    {};
+
     template <>
     struct signature_of<void>
     {

src/Error.cpp

@@ -32,17 +32,24 @@
 
 namespace sdbus
 {
-    sdbus::Error createError(int errNo, std::string customMsg)
+    Error createError(int errNo, std::string customMsg)
     {
         sd_bus_error sdbusError = SD_BUS_ERROR_NULL;
         sd_bus_error_set_errno(&sdbusError, errNo);
         SCOPE_EXIT{ sd_bus_error_free(&sdbusError); };
 
-        Error::Name name(sdbusError.name);
+        Error::Name name(sd_bus_error_is_set(&sdbusError) ? sdbusError.name : "");
         std::string message(std::move(customMsg));
-        message.append(" (");
-        message.append(sdbusError.message);
-        message.append(")");
+        if (!message.empty() && sdbusError.message != nullptr)
+        {
+            message.append(" (");
+            message.append(sdbusError.message);
+            message.append(")");
+        }
+        else if (sdbusError.message != nullptr)
+        {
+            message = sdbusError.message;
+        }
 
         return Error(std::move(name), std::move(message));
     }

tests/unittests/Types_test.cpp

@@ -97,6 +97,29 @@ TEST(AVariant, CanBeCopied)
     ASSERT_THAT(variantCopy2.get<std::string>(), Eq(value));
 }
 
+TEST(AVariant, CanBeMoved)
+{
+    auto value = "hello"s;
+    sdbus::Variant variant(value);
+
+    auto movedVariant{std::move(variant)};
+
+    ASSERT_THAT(movedVariant.get<std::string>(), Eq(value));
+    ASSERT_TRUE(variant.isEmpty());
+}
+
+TEST(AVariant, CanBeMovedIntoAMap)
+{
+    auto value = "hello"s;
+    sdbus::Variant variant(value);
+
+    std::map<std::string, sdbus::Variant> mymap;
+    mymap.try_emplace("payload", std::move(variant));
+
+    ASSERT_THAT(mymap["payload"].get<std::string>(), Eq(value));
+    ASSERT_TRUE(variant.isEmpty());
+}
+
 TEST(AVariant, IsNotEmptyWhenContainsAValue)
 {
     sdbus::Variant v("hello");
@@ -430,6 +453,7 @@ TEST(AnError, CanBeConstructedFromANameAndAMessage)
     auto error = sdbus::Error(sdbus::Error::Name{"org.sdbuscpp.error"}, "message");
     EXPECT_THAT(error.getName(), Eq<std::string>("org.sdbuscpp.error"));
     EXPECT_THAT(error.getMessage(), Eq<std::string>("message"));
+    EXPECT_TRUE(error.isValid());
 }
 
 TEST(AnError, CanBeConstructedFromANameOnly)
@@ -439,6 +463,47 @@ TEST(AnError, CanBeConstructedFromANameOnly)
     EXPECT_THAT(error1.getName(), Eq<std::string>("org.sdbuscpp.error"));
     EXPECT_THAT(error2.getName(), Eq<std::string>("org.sdbuscpp.error"));
 
-    EXPECT_THAT(error1.getMessage(), Eq<std::string>(""));
-    EXPECT_THAT(error2.getMessage(), Eq<std::string>(""));
+    EXPECT_TRUE(error1.getMessage().empty());
+    EXPECT_TRUE(error2.getMessage().empty());
+
+    EXPECT_TRUE(error1.isValid());
+    EXPECT_TRUE(error2.isValid());
+}
+
+TEST(AnError, IsInvalidWhenConstructedWithAnEmptyName)
+{
+    auto error = sdbus::Error({});
+
+    EXPECT_TRUE(error.getName().empty());
+    EXPECT_TRUE(error.getMessage().empty());
+    EXPECT_FALSE(error.isValid());
+}
+
+TEST(AnErrorFactory, CanCreateAnErrorFromErrno)
+{
+    auto error = sdbus::createError(ENOENT, "custom message");
+
+    EXPECT_THAT(error.getName(), Eq<std::string>("org.freedesktop.DBus.Error.FileNotFound"));
+    EXPECT_THAT(error.getMessage(), Eq<std::string>("custom message (No such file or directory)"));
+    EXPECT_TRUE(error.isValid());
+}
+
+#ifndef SDBUS_basu // Creating error from invalid errno is not supported on basu backend
+TEST(AnErrorFactory, CreatesGenericErrorWhenErrnoIsUnknown)
+{
+    auto error = sdbus::createError(123456, "custom message");
+
+    EXPECT_THAT(error.getName(), Eq<std::string>("org.freedesktop.DBus.Error.Failed"));
+    EXPECT_THAT(error.getMessage(), Eq<std::string>("custom message (Unknown error 123456)"));
+    EXPECT_TRUE(error.isValid());
+}
+#endif // SDBUS_basu
+
+TEST(AnErrorFactory, CreatesEmptyInvalidErrorWhenErrnoIsZero)
+{
+    auto error = sdbus::createError(0, "custom message");
+
+    EXPECT_TRUE(error.getName().empty());
+    EXPECT_THAT(error.getMessage(), Eq<std::string>("custom message"));
+    EXPECT_FALSE(error.isValid());
 }

tools/CMakeLists.txt

@@ -4,7 +4,7 @@
 
 cmake_minimum_required(VERSION 3.5)
 
-project(sdbus-c++-tools VERSION 2.1.0)
+project(sdbus-c++-tools VERSION 2.2.0)
 
 include(GNUInstallDirs)