fix: No output from failed asserts in tests

src/util/Assert.cpp

@@ -54,10 +54,10 @@ OnAssert::resetAction()
 void
 OnAssert::defaultAction(std::string_view message)
 {
-    if (LogServiceState::initialized()) {
+    if (LogServiceState::initialized() and LogServiceState::hasSinks()) {
         LOG(LogService::fatal()) << message;
     } else {
-        std::cerr << message;
+        std::cerr << message << std::endl;
     }
     std::exit(EXIT_FAILURE);  // std::abort does not flush gcovr output and causes uncovered lines
 }

src/util/log/Logger.cpp

@@ -271,6 +271,12 @@ LogServiceState::initialized()
     return initialized_;
 }
 
+bool
+LogServiceState::hasSinks()
+{
+    return not sinks_.empty();
+}
+
 void
 LogServiceState::reset()
 {

src/util/log/Logger.hpp

@@ -267,6 +267,14 @@ class LogServiceState {
     [[nodiscard]] static bool
     initialized();
 
+    /**
+     * @brief Whether the LogService has any sink. If there is no sink, logger will not log messages anywhere.
+     *
+     * @return true if the LogService has at least one sink
+     */
+    [[nodiscard]] static bool
+    hasSinks();
+
     /**
      * @brief Reset the logging service to uninitialized state.
      */