diff --git a/extras/tests/Helpers/Allocators.hpp b/extras/tests/Helpers/Allocators.hpp
index ab4bbea1..ba648794 100644
--- a/extras/tests/Helpers/Allocators.hpp
+++ b/extras/tests/Helpers/Allocators.hpp
@@ -120,6 +120,7 @@ class SpyingAllocator : public ArduinoJson::Allocator {
         _upstream->reallocate(block, sizeof(AllocatedBlock) + n - 1));
     if (block) {
       _log << AllocatorLog::Reallocate(oldSize, n);
+      ARDUINOJSON_ASSERT(block->size == oldSize);
       block->size = n;
       return block->payload;
     } else {
@@ -128,6 +129,10 @@ class SpyingAllocator : public ArduinoJson::Allocator {
     }
   }
 
+  void clearLog() {
+    _log = AllocatorLog();
+  }
+
   const AllocatorLog& log() const {
     return _log;
   }