tests: add threadutil tests

Author: jamesob

src/Makefile.test.include

@@ -138,6 +138,7 @@ BITCOIN_TESTS =\
   test/skiplist_tests.cpp \
   test/streams_tests.cpp \
   test/sync_tests.cpp \
+  test/util_threadnames_tests.cpp \
   test/timedata_tests.cpp \
   test/torcontrol_tests.cpp \
   test/transaction_tests.cpp \

src/test/util_threadnames_tests.cpp

@@ -0,0 +1,73 @@
+// Copyright (c) 2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <util/threadnames.h>
+#include <test/setup_common.h>
+
+#include <thread>
+#include <vector>
+#include <set>
+#include <mutex>
+
+#if defined(HAVE_CONFIG_H)
+#include <config/bitcoin-config.h>
+#endif
+
+#include <boost/test/unit_test.hpp>
+
+BOOST_FIXTURE_TEST_SUITE(util_threadnames_tests, BasicTestingSetup)
+
+const std::string TEST_THREAD_NAME_BASE = "test_thread.";
+
+/**
+ * Run a bunch of threads to all call util::ThreadRename.
+ *
+ * @return the set of name each thread has after attempted renaming.
+ */
+std::set<std::string> RenameEnMasse(int num_threads)
+{
+    std::vector<std::thread> threads;
+    std::set<std::string> names;
+    std::mutex lock;
+
+    auto RenameThisThread = [&](int i) {
+        util::ThreadRename(TEST_THREAD_NAME_BASE + std::to_string(i));
+        std::lock_guard<std::mutex> guard(lock);
+        names.insert(util::ThreadGetInternalName());
+    };
+
+    for (int i = 0; i < num_threads; ++i) {
+        threads.push_back(std::thread(RenameThisThread, i));
+    }
+
+    for (std::thread& thread : threads) thread.join();
+
+    return names;
+}
+
+/**
+ * Rename a bunch of threads with the same basename (expect_multiple=true), ensuring suffixes are
+ * applied properly.
+ */
+BOOST_AUTO_TEST_CASE(util_threadnames_test_rename_threaded)
+{
+    BOOST_CHECK_EQUAL(util::ThreadGetInternalName(), "");
+
+#if !defined(HAVE_THREAD_LOCAL)
+    // This test doesn't apply to platforms where we don't have thread_local.
+    return;
+#endif
+
+    std::set<std::string> names = RenameEnMasse(100);
+
+    BOOST_CHECK_EQUAL(names.size(), 100);
+
+    // Names "test_thread.[n]" should exist for n = [0, 99]
+    for (int i = 0; i < 100; ++i) {
+        BOOST_CHECK(names.find(TEST_THREAD_NAME_BASE + std::to_string(i)) != names.end());
+    }
+
+}
+
+BOOST_AUTO_TEST_SUITE_END()