Reimplement constant acceleration groups

[alexxy/gromacs.git] / src / testutils / testmatchers.cpp

diff --git a/src/testutils/testmatchers.cpp b/src/testutils/testmatchers.cpp
index 782d0bd162468fb04f748f717b946a77d2fda5ce..1e7f5bd9fa1ab2ac4e3ccad71a77583ca14c2a9b 100644 (file)
--- a/src/testutils/testmatchers.cpp
+++ b/src/testutils/testmatchers.cpp
@@ -1,7 +1,7 @@
 /*
  * This file is part of the GROMACS molecular simulation package.
  *
- * Copyright (c) 2018,2019,2020, by the GROMACS development team, led by
+ * Copyright (c) 2018,2019,2020,2021, by the GROMACS development team, led by
  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
  * and including many others, as listed in the AUTHORS file in the
  * top-level source directory and at http://www.gromacs.org.
@@ -80,10 +80,14 @@ public:
         {
             return true;
         }
-        *listener->stream() << "  Actual value: " << value2 << std::endl
-                            << "Expected value: " << value1 << std::endl
-                            << "    Difference: " << diff.toString() << std::endl
-                            << "     Tolerance: " << tolerance_.toString(diff);
+        if (listener->stream())
+        {
+            *listener->stream() << "  Actual value: " << value2 << std::endl
+                                << "Expected value: " << value1 << std::endl
+                                << "    Difference: " << diff.toString() << std::endl
+                                << "     Tolerance: " << tolerance_.toString(diff);
+        }
+
         return false;
     }
     //! Describe to a human what matching means.