response to review

CHANGES.md

@@ -13,6 +13,11 @@ ones in. -->
 -------------------------------------------------------------------------------
 ## __cylc-8.1.0 (<span actions:bind='release-date'>Upcoming</span>)__
 
+### Breaking Changes
+
+* Workflows started with Cylc 8.0 which contain multiple "flows" cannot be
+  restarted with Cylc 8.1 due to database changes.
+
 ### Enhancements
 
 [#5184](https://github.com/cylc/cylc-flow/pull/5184) - scan for active
@@ -33,8 +38,6 @@ command to validate, install and play a workflow.
 [#5081](https://github.com/cylc/cylc-flow/pull/5081) - Reduced amount that
 gets logged at "INFO" level in scheduler logs.
 
-### Fixes
-
 [#5259](https://github.com/cylc/cylc-flow/pull/5259) - Add flow_nums
 to task_jobs table in the workflow database.
 

tests/unit/test_workflow_db_mgr.py

@@ -61,7 +61,7 @@ def _inner(values):
     return _inner
 
 
-def test_upgrade_pre_804_fails_on_multiple_flows(_setup_db):
+def test_upgrade_pre_810_fails_on_multiple_flows(_setup_db):
     values = (
         r'INSERT INTO task_states VALUES'
         r"    ('foo', '10050101T0000Z', '[1, 3]',"
@@ -72,12 +72,12 @@ def test_upgrade_pre_804_fails_on_multiple_flows(_setup_db):
     pri_dao = CylcWorkflowDAO(db_file_name)
     with pytest.raises(
         CylcError,
-        match='^Cannot .* 8.0.3 to 8.0.4 .* used.$'
+        match='^Cannot .* 8.0.x to 8.1.0 .* used.$'
     ):
-        WorkflowDatabaseManager.upgrade_pre_804(pri_dao)
+        WorkflowDatabaseManager.upgrade_pre_810(pri_dao)
 
 
-def test_upgrade_pre_804_pass_on_single_flow(_setup_db):
+def test_upgrade_pre_810_pass_on_single_flow(_setup_db):
     values = (
         r'INSERT INTO task_states VALUES'
         r"    ('foo', '10050101T0000Z', '[1]',"
@@ -86,7 +86,8 @@ def test_upgrade_pre_804_pass_on_single_flow(_setup_db):
     )
     db_file_name = _setup_db(values)
     pri_dao = CylcWorkflowDAO(db_file_name)
-    WorkflowDatabaseManager.upgrade_pre_804(pri_dao)
+    WorkflowDatabaseManager.upgrade_pre_810(pri_dao)
     conn = sqlite3.connect(db_file_name)
-    result = conn.execute('SELECT flow_nums FROM task_jobs;').fetchall()[0][0]
+    result = conn.execute(
+        'SELECT DISTINCT flow_nums FROM task_jobs;').fetchall()[0][0]
     assert result == '[1]'