Problem: no unittests for mtrie

Solution: made mtrie generic (to remove complex dependency on pipe_t),
and added some unit tests

unittests/unittest_mtrie.cpp

@@ -0,0 +1,113 @@
+/*
+Copyright (c) 2018 Contributors as noted in the AUTHORS file
+
+This file is part of 0MQ.
+
+0MQ is free software; you can redistribute it and/or modify it under
+the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 3 of the License, or
+(at your option) any later version.
+
+0MQ is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "../tests/testutil.hpp"
+
+#if defined(min)
+#undef min
+#endif
+
+#include <generic_mtrie_impl.hpp>
+
+#include <unity.h>
+
+void setUp ()
+{
+}
+void tearDown ()
+{
+}
+
+void test_create ()
+{
+    zmq::generic_mtrie_t<int> mtrie;
+}
+
+void mtrie_count (int *pipe, void *arg)
+{
+    LIBZMQ_UNUSED (pipe);
+    int *count = static_cast<int *> (arg);
+    ++*count;
+}
+
+void test_check_empty_match_nonempty_data ()
+{
+    zmq::generic_mtrie_t<int> mtrie;
+    const zmq::generic_mtrie_t<int>::prefix_t test_name =
+      reinterpret_cast<zmq::generic_mtrie_t<int>::prefix_t> ("foo");
+
+    int count = 0;
+    mtrie.match (test_name, 3, mtrie_count, &count);
+    TEST_ASSERT_EQUAL_INT (0, count);
+}
+
+void test_check_empty_match_empty_data ()
+{
+    zmq::generic_mtrie_t<int> mtrie;
+
+    int count = 0;
+    mtrie.match (NULL, 0, mtrie_count, &count);
+    TEST_ASSERT_EQUAL_INT (0, count);
+}
+
+void test_add_single_entry_match_exact ()
+{
+    int pipe;
+
+    zmq::generic_mtrie_t<int> mtrie;
+    const zmq::generic_mtrie_t<int>::prefix_t test_name =
+      reinterpret_cast<zmq::generic_mtrie_t<int>::prefix_t> ("foo");
+
+    bool res = mtrie.add (test_name, 3, &pipe);
+    TEST_ASSERT_TRUE (res);
+
+    int count = 0;
+    mtrie.match (test_name, 3, mtrie_count, &count);
+    TEST_ASSERT_EQUAL_INT (1, count);
+}
+
+void test_add_rm_single_entry_match_exact ()
+{
+    int pipe;
+    zmq::generic_mtrie_t<int> mtrie;
+    const zmq::generic_mtrie_t<int>::prefix_t test_name =
+      reinterpret_cast<zmq::generic_mtrie_t<int>::prefix_t> ("foo");
+
+    mtrie.add (test_name, 3, &pipe);
+    bool res = mtrie.rm (test_name, 3, &pipe);
+    TEST_ASSERT_TRUE (res);
+
+    int count = 0;
+    mtrie.match (test_name, 3, mtrie_count, &count);
+    TEST_ASSERT_EQUAL_INT (0, count);
+}
+
+int main (void)
+{
+    setup_test_environment ();
+
+    UNITY_BEGIN ();
+    RUN_TEST (test_create);
+    RUN_TEST (test_check_empty_match_nonempty_data);
+    RUN_TEST (test_check_empty_match_empty_data);
+    RUN_TEST (test_add_single_entry_match_exact);
+    RUN_TEST (test_add_rm_single_entry_match_exact);
+
+    return UNITY_END ();
+}