tests: Add some trivial tests for g_thread_init()

It’s deprecated, but the big red 0/0/0 line for the `glib/gthread`
directory in the lcov output for GLib is driving me nuts.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>

gthread/meson.build

@@ -36,3 +36,7 @@ pkg.generate(libgthread,
 
 libgthread_dep = declare_dependency(link_with : libgthread)
 meson.override_dependency('gthread-2.0', libgthread_dep)
+
+if build_tests
+  subdir('tests')
+endif

gthread/tests/init.c

@@ -0,0 +1,68 @@
+/* GLib testing framework examples and tests
+ *
+ * Copyright © 2022 Endless OS Foundation, LLC
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
+ * This library 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 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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 library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Philip Withnall <pwithnall@endlessos.org>
+ */
+
+#include <glib.h>
+#include <locale.h>
+
+
+/* All of GThread is deprecated, but that’s OK */
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+
+static void
+test_thread_deprecated_init (void)
+{
+  const GThreadFunctions functions = { NULL, };
+
+  /* Should be a no-op. */
+  g_thread_init (NULL);
+
+  /* Should emit a warning. */
+  g_test_expect_message ("GThread", G_LOG_LEVEL_WARNING,
+                         "GThread system no longer supports custom thread implementations.");
+  g_thread_init ((gpointer) &functions);
+  g_test_assert_expected_messages ();
+}
+
+static void
+test_thread_deprecated_init_with_errorcheck_mutexes (void)
+{
+  /* Should warn. */
+  g_test_expect_message ("GThread", G_LOG_LEVEL_WARNING,
+                         "GThread system no longer supports errorcheck mutexes.");
+  g_thread_init_with_errorcheck_mutexes (NULL);
+  g_test_assert_expected_messages ();
+}
+
+int
+main (int   argc,
+      char *argv[])
+{
+  setlocale (LC_ALL, "");
+  g_test_init (&argc, &argv, G_TEST_OPTION_ISOLATE_DIRS, NULL);
+
+  g_test_add_func ("/thread/deprecated/init", test_thread_deprecated_init);
+  g_test_add_func ("/thread/deprecated/init-with-errorcheck-mutexes", test_thread_deprecated_init_with_errorcheck_mutexes);
+
+  return g_test_run ();
+}
+
+G_GNUC_END_IGNORE_DEPRECATIONS

gthread/tests/meson.build

@@ -0,0 +1,48 @@
+gthread_tests = {
+  'init' : {},
+}
+
+test_env = environment()
+test_env.set('G_TEST_SRCDIR', meson.current_source_dir())
+test_env.set('G_TEST_BUILDDIR', meson.current_build_dir())
+
+test_deps = [thread_dep, libglib_dep, libgthread_dep]
+test_cargs = ['-DG_LOG_DOMAIN="GLib-GThread"', '-UG_DISABLE_ASSERT']
+test_cpp_args = test_cargs
+
+foreach test_name, extra_args : gthread_tests
+  source = extra_args.get('source', test_name + '.c')
+  install = installed_tests_enabled and extra_args.get('install', true)
+
+  if install
+    test_conf = configuration_data()
+    test_conf.set('installed_tests_dir', installed_tests_execdir)
+    test_conf.set('program', test_name)
+    test_conf.set('env', '')
+    configure_file(
+      input: installed_tests_template_tap,
+      output: test_name + '.test',
+      install_dir: installed_tests_metadir,
+      install_tag: 'tests',
+      configuration: test_conf
+    )
+  endif
+
+  exe = executable(test_name, source,
+    c_args : test_cargs + extra_args.get('c_args', []),
+    cpp_args : test_cpp_args + extra_args.get('cpp_args', []),
+    dependencies : test_deps + extra_args.get('dependencies', []),
+    install_dir: installed_tests_execdir,
+    install_tag: 'tests',
+    install: install,
+  )
+
+  suite = ['gthread'] + extra_args.get('suite', [])
+  timeout = suite.contains('slow') ? test_timeout_slow : test_timeout
+
+  if extra_args.get('can_fail', false)
+    suite += 'failing'
+  endif
+
+  test(test_name, exe, env : test_env, timeout : timeout, suite : suite)
+endforeach