Better visibility for C tests:

 - turn on output-on-failure by default
 - explain how to run tests in README

Author: vmallet

CMakeLists.txt

@@ -184,6 +184,7 @@ ENDIF ()
 
 IF (MSGPACK_BUILD_TESTS)
     ENABLE_TESTING ()
+    list(APPEND CMAKE_CTEST_ARGUMENTS "--output-on-failure")
     # MEMORYCHECK_COMMAND_OPTIONS needs to place prior to CTEST_MEMORYCHECK_COMMAND
     SET (MEMORYCHECK_COMMAND_OPTIONS "--leak-check=full --show-leak-kinds=definite,possible --error-exitcode=1")
     FIND_PROGRAM(CTEST_MEMORYCHECK_COMMAND NAMES valgrind)

README.md

@@ -82,6 +82,10 @@ How to build:
     $ make
     $ sudo make install
 
+How to run tests:
+
+    $ make test
+
 When you use the C part of `msgpack-c`, you need to build and link the library. By default, both static/shared libraries are built. If you want to build only static library, set `BUILD_SHARED_LIBS=OFF` to cmake. If you want to build only shared library, set `BUILD_SHARED_LIBS=ON`.
 
 #### GUI on Windows