use llarp::LogSilencer to shut up loging in unit tests

llarp/util/logging/logger.cpp

@@ -174,14 +174,17 @@ namespace llarp
     }
   }
 
-  void
-  SilenceLog(std::function<void(void)> func)
+  LogSilencer::LogSilencer() : LogSilencer(LogContext::Instance())
+  {
+  }
+
+  LogSilencer::LogSilencer(LogContext& ctx) : stream(std::move(ctx.logStream))
+  {
+  }
+
+  LogSilencer::~LogSilencer()
   {
-    auto& log = LogContext::Instance();
-    ILogStream_ptr oldStream = std::move(log.logStream);
-    log.logStream = nullptr;
-    func();
-    log.logStream = std::move(oldStream);
+    LogContext::Instance().logStream = std::move(stream);
   }
 
 }  // namespace llarp

llarp/util/logging/logger.hpp

@@ -60,9 +60,17 @@ namespace llarp
         std::shared_ptr<thread::ThreadPool> threadpool);
   };
 
-  // call a function where the logging is slienced
-  void
-  SilenceLog(std::function<void(void)> func);
+  /// RAII type to turn logging off
+  /// logging is suppressed as long as the silencer is in scope
+  struct LogSilencer
+  {
+    LogSilencer();
+    ~LogSilencer();
+    explicit LogSilencer(LogContext& ctx);
+
+   private:
+    ILogStream_ptr stream;
+  };
 
   void
   SetLogLevel(LogLevel lvl);

test/main.cpp

@@ -1,5 +1,7 @@
 #include <gtest/gtest.h>
 
+#include <util/logging/logger.hpp>
+
 #ifdef _WIN32
 #include <winsock2.h>
 int
@@ -20,6 +22,7 @@ startWinsock()
 int
 main(int argc, char** argv)
 {
+  llarp::LogSilencer shutup;
 #ifdef _WIN32
   if (startWinsock())
     return -1;

test/regress/2020-06-08-key-backup-bug.cpp

@@ -19,7 +19,7 @@ make_context(fs::path keyfile)
 
 TEST_CASE("key backup bug regression test", "[regress]")
 {
-  llarp::SilenceLog([]() {
+  llarp::LogSilencer shutup;
   for (const fs::path& path : {"regress-1.private", "regress-2.private", ""})
   {
     llarp::service::Address endpointAddress{};
@@ -59,5 +59,4 @@ TEST_CASE("key backup bug regression test", "[regress]")
     }
     fs::remove(path);
   }
-  });
 }