Add test helper to use std::optional via CPPUNIT_ASSERT_EQUAL

CMakeLists.txt

@@ -114,8 +114,8 @@ set(META_APP_AUTHOR "Martchus")
 set(META_APP_URL "https://github.com/${META_APP_AUTHOR}/${META_PROJECT_NAME}")
 set(META_APP_DESCRIPTION "Useful C++ classes and routines such as argument parser, IO and conversion utilities")
 set(META_VERSION_MAJOR 5)
-set(META_VERSION_MINOR 14)
-set(META_VERSION_PATCH 1)
+set(META_VERSION_MINOR 15)
+set(META_VERSION_PATCH 0)
 
 # find required 3rd party libraries
 include(3rdParty)

tests/testutils.h

@@ -5,6 +5,7 @@
 #include "../misc/traits.h"
 
 #include <iomanip>
+#include <optional>
 #include <ostream>
 #include <string>
 
@@ -196,6 +197,19 @@ CPP_UTILITIES_EXPORT int execHelperAppInSearchPath(
     const char *appName, const char *const *args, std::string &output, std::string &errors, bool suppressLogging = false, int timeout = -1);
 #endif // PLATFORM_UNIX
 
+/*!
+ * \brief Allows printing std::optional objects so those can be asserted using CPPUNIT_ASSERT_EQUAL.
+ */
+template <typename Optional, Traits::EnableIf<Traits::IsSpecializationOf<Optional, std::optional>> * = nullptr>
+inline std::ostream &operator<<(std::ostream &out, const Optional &optional)
+{
+    if (optional.has_value()) {
+        return out << *optional;
+    } else {
+        return out << "[no value]";
+    }
+}
+
 /*!
  * \brief The AsHexNumber class allows printing values asserted with cppunit (or similar test framework) using the
  *        hex system in the error case.