Add unit test of help_formatter

Modelled after help_entry's unit test.

Author: tautschnig

unit/Makefile

@@ -144,6 +144,7 @@ SRC += analyses/ai/ai.cpp \
        util/format_number_range.cpp \
        util/get_base_name.cpp \
        util/graph.cpp \
+       util/help_formatter.cpp \
        util/interval/add.cpp \
        util/interval/bitwise.cpp \
        util/interval/comparisons.cpp \

unit/util/help_formatter.cpp

@@ -0,0 +1,21 @@
+/******************************************************************\
+
+Module: help formatter unit tests
+
+Author: Michael Tautschnig
+
+\******************************************************************/
+
+#include <util/help_formatter.h>
+
+#include <testing-utils/use_catch.h>
+
+#include <sstream>
+
+TEST_CASE("help_formatter", "[core][util]")
+{
+  std::ostringstream oss;
+  oss.clear();
+  oss << help_formatter("--abc \t xyz\n");
+  REQUIRE(oss.str() == "--abc                         xyz\n");
+}