tests: threads: Test if 1st child message promotes its thread

lib/tests/testdir3/sort/1st-child-promotes-thread/cur/A

@@ -0,0 +1,7 @@
+From: testfrom@example.com
+To: testto@example.com
+Subject: A
+Message-Id: <A@msg.id>
+Date: Sat, 17 May 2014 10:00:00 +0000
+
+A

lib/tests/testdir3/sort/1st-child-promotes-thread/cur/B

@@ -0,0 +1,7 @@
+From: testfrom@example.com
+To: testto@example.com
+Subject: B
+Message-Id: <B@msg.id>
+Date: Sat, 17 May 2014 10:00:00 +0000
+
+B

lib/tests/testdir3/sort/1st-child-promotes-thread/cur/C

@@ -0,0 +1,7 @@
+From: testfrom@example.com
+To: testto@example.com
+Subject: C
+Message-Id: <C@msg.id>
+Date: Sat, 17 May 2014 10:00:00 +0000
+
+C

lib/tests/testdir3/sort/1st-child-promotes-thread/cur/D

@@ -0,0 +1,9 @@
+From: testfrom@example.com
+To: testto@example.com
+Subject: D
+Message-Id: <D@msg.id>
+References: <B@msg.id>
+In-reply-to: <B@msg.id>
+Date: Sat, 17 May 2014 10:00:00 +0000
+
+D

mu/tests/test-mu-threads.c

@@ -117,7 +117,8 @@ fill_database (const char *testdir)
 
 /* note: this also *moves the iter* */
 static MuMsgIter*
-run_and_get_iter (const char *xpath, const char *query)
+run_and_get_iter_full (const char *xpath, const char *query,
+		       MuMsgFieldId sort_field, MuQueryFlags flags)
 {
 	MuQuery  *mquery;
 	MuStore *store;
@@ -130,14 +131,21 @@ run_and_get_iter (const char *xpath, const char *query)
 	mu_store_unref (store);
 	g_assert (query);
 
-	iter = mu_query_run (mquery, query, MU_MSG_FIELD_ID_DATE,
-			     -1, MU_QUERY_FLAG_THREADS, NULL);
+	flags |= MU_QUERY_FLAG_THREADS;
+	iter = mu_query_run (mquery, query, sort_field, -1, flags, NULL);
 	mu_query_destroy (mquery);
 	g_assert (iter);
 
 	return iter;
 }
 
+static MuMsgIter*
+run_and_get_iter (const char *xpath, const char *query)
+{
+	return run_and_get_iter_full (xpath, query, MU_MSG_FIELD_ID_DATE,
+				      MU_QUERY_FLAG_NONE);
+}
+
 static void
 test_mu_threads_01 (void)
 {
@@ -216,6 +224,76 @@ test_mu_threads_rogue (void)
 	mu_msg_iter_destroy (iter);
 }
 
+static MuMsgIter*
+query_testdir (const char *query, MuMsgFieldId sort_field,  gboolean descending)
+{
+	MuMsgIter *iter;
+	gchar *xpath;
+	MuQueryFlags flags;
+
+	flags = MU_QUERY_FLAG_NONE;
+	if (descending)
+		flags |= MU_QUERY_FLAG_DESCENDING;
+
+	xpath = fill_database (MU_TESTMAILDIR3);
+	g_assert (xpath != NULL);
+
+	iter = run_and_get_iter_full (xpath, query, sort_field, flags);
+	g_assert (iter != NULL);
+	g_assert (!mu_msg_iter_is_done (iter));
+
+	g_free (xpath);
+	return iter;
+}
+
+static void
+check_sort_by_subject (const char *query, const tinfo expected[],
+		       guint n_expected, gboolean descending)
+{
+	MuMsgIter *iter;
+
+	iter = query_testdir (query, MU_MSG_FIELD_ID_SUBJECT, descending);
+	foreach_assert_tinfo_equal (iter, expected, n_expected);
+	mu_msg_iter_destroy (iter);
+}
+
+static void
+check_sort_by_subject_asc (const char *query, const tinfo expected[],
+			   guint n_expected)
+{
+	check_sort_by_subject (query, expected, n_expected, FALSE);
+}
+
+static void
+check_sort_by_subject_desc (const char *query, const tinfo expected[],
+			    guint n_expected)
+{
+	check_sort_by_subject (query, expected, n_expected, TRUE);
+}
+
+static void
+test_mu_threads_sort_1st_child_promotes_thread (void)
+{
+	const char *query = "maildir:/sort/1st-child-promotes-thread";
+
+	const tinfo expected_asc [] = {
+		{ "0", "A@msg.id", "A"},
+		{ "1", "C@msg.id", "C"},
+		{ "2", "B@msg.id", "B"},
+		{ "2:0", "D@msg.id", "D"},
+	};
+	const tinfo expected_desc [] = {
+		{ "0", "B@msg.id", "B"},
+		{ "0:0", "D@msg.id", "D"},
+		{ "1", "C@msg.id", "C"},
+		{ "2", "A@msg.id", "A"},
+	};
+
+	check_sort_by_subject_asc (query, expected_asc,
+				   G_N_ELEMENTS (expected_asc));
+	check_sort_by_subject_desc (query, expected_desc,
+				    G_N_ELEMENTS (expected_desc));
+}
 
 
 int
@@ -227,6 +305,8 @@ main (int argc, char *argv[])
 
 	g_test_add_func ("/mu-query/test-mu-threads-01", test_mu_threads_01);
 	g_test_add_func ("/mu-query/test-mu-threads-rogue", test_mu_threads_rogue);
+	g_test_add_func ("/mu-query/test-mu-threads-sort-1st-child-promotes-thread",
+			 test_mu_threads_sort_1st_child_promotes_thread);
 
 	g_log_set_handler (NULL,
 			   G_LOG_LEVEL_MASK | G_LOG_FLAG_FATAL| G_LOG_FLAG_RECURSION,