diff --git a/src/core/unit_tests/EspressoSystemStandAlone_test.cpp b/src/core/unit_tests/EspressoSystemStandAlone_test.cpp
index ab489668f0e..d7ef406464f 100644
--- a/src/core/unit_tests/EspressoSystemStandAlone_test.cpp
+++ b/src/core/unit_tests/EspressoSystemStandAlone_test.cpp
@@ -97,7 +97,7 @@ BOOST_FIXTURE_TEST_CASE(espresso_system_stand_alone, ParticleFactory) {
   auto const comm = boost::mpi::communicator();
   auto const rank = comm.rank();
   auto const n_nodes = comm.size();
-#if defined(FPE) and not defined (__APPLE__)
+#if defined(FPE) and not defined(__APPLE__)
   auto const trap = fe_trap::make_unique_scoped();
 #endif