encoding: provide FormattedOutputFunction for Block

refs #2225

Change-Id: Ie38539ff93293b3919789043b01e09b573fb619a
diff --git a/tests/unit-tests/security/signature-sha256-with-ecdsa.t.cpp b/tests/unit-tests/security/signature-sha256-with-ecdsa.t.cpp
index 658b1c2..a819279 100644
--- a/tests/unit-tests/security/signature-sha256-with-ecdsa.t.cpp
+++ b/tests/unit-tests/security/signature-sha256-with-ecdsa.t.cpp
@@ -102,7 +102,7 @@
   sig.setKeyLocator(Name("/test/another/key/locator"));
 
   const Block& encodeSigInfoBlock2 = sig.getInfo();
-  BOOST_CHECK(sigInfoBlock != encodeSigInfoBlock2);
+  BOOST_CHECK_NE(sigInfoBlock, encodeSigInfoBlock2);
 }
 
 BOOST_AUTO_TEST_CASE(DataSignature)