Tests to ensure simulation mode is conserved across restarts of the s…

…cheduler.

tests/integration/test_mode_on_restart.py

@@ -0,0 +1,47 @@
+# THIS FILE IS PART OF THE CYLC WORKFLOW ENGINE.
+# Copyright (C) NIWA & British Crown (Met Office) & Contributors.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"""What happens to the mode on restart?
+
++--------------------+--------+-------+-------+
+| ↓restart \ start → | live   | sim   | dummy |
++====================+========+=======+=======+
+| live               | live   | sim * | ???   |
+| sim                | live * | sim   | ???   |
+| dummy              | ???    | ???   | dummy |
++--------------------+--------+-------+-------+
+
+* A warning ought to be emitted, since the user doesn't otherwise know
+  what's happening.
+"""
+
+import pytest
+
+
+@pytest.mark.parametrize('mode_before', (('live'), ('simulation')))
+@pytest.mark.parametrize('mode_after', (('live'), ('simulation')))
+async def test_restart_mode(
+    flow, scheduler, start, one_conf, mode_before, mode_after
+):
+    """Restarting a workflow in live mode leads to workflow in live mode
+    """
+    id_ = flow(one_conf)
+    schd = scheduler(id_, run_mode=mode_before)
+    async with start(schd):
+        assert schd.config.run_mode() == mode_before
+
+    schd.options.run_mode = mode_after
+    async with start(schd):
+        assert schd.config.run_mode() == mode_before