data-store prune of optional break

CHANGES.md

@@ -51,6 +51,9 @@ default job runner directives for platforms.
 
 ### Fixes
 
+[#4976](https://github.com/cylc/cylc-flow/pull/4976) - Fix bug causing tasks
+to be stuck in UI due to discontinued graph of optional outputs.
+
 [#4975](https://github.com/cylc/cylc-flow/pull/4975) - Fix selection of
 platforms from `[job]` and `[remote]` configs.
 

cylc/flow/data_store_mgr.py

@@ -774,6 +774,12 @@ def remove_pool_node(self, name, point):
             self.prune_flagged_nodes.update(self.prune_trigger_nodes[tp_id])
             del self.prune_trigger_nodes[tp_id]
             self.updates_pending = True
+        elif (
+                tp_id in self.n_window_nodes and
+                self.n_window_nodes[tp_id].isdisjoint(self.all_task_pool)
+        ):
+            self.prune_flagged_nodes.add(tp_id)
+            self.updates_pending = True
 
     def add_pool_node(self, name, point):
         """Add external ID reference for internal task pool node."""

tests/functional/data-store/00-prune-optional-break.t

@@ -0,0 +1,95 @@
+#!/usr/bin/env bash
+# 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/>.
+#-------------------------------------------------------------------------------
+# Test data-store pruning
+. "$(dirname "$0")/test_header"
+#-------------------------------------------------------------------------------
+set_test_number 3
+#-------------------------------------------------------------------------------
+init_workflow "${TEST_NAME_BASE}" << __FLOW__
+[scheduling]
+    cycling mode = integer
+    initial cycle point = 1
+    final cycle point = 1
+    [[graph]]
+        P1 = """
+a? => b? => c?
+d => e
+"""
+[runtime]
+    [[a,c,e]]
+        script = true
+    [[b]]
+        script = false
+    [[d]]
+        script = """
+cylc workflow-state \$CYLC_WORKFLOW_ID --task=b --point=1 --status=failed --interval=2
+cylc pause \$CYLC_WORKFLOW_ID
+"""
+__FLOW__
+
+# run workflow
+run_ok "${TEST_NAME_BASE}-run" cylc play "${WORKFLOW_NAME}"
+
+cylc workflow-state "${WORKFLOW_NAME}" --task=d --point=1 --status=succeeded --interval=2 --max-polls=60
+
+# query workflow
+TEST_NAME="${TEST_NAME_BASE}-prune-optional-break"
+read -r -d '' optionalBreak <<_args_
+{
+  "request_string": "
+query {
+  workflows {
+    name
+    taskProxies (sort: {keys: [\"name\"]}) {
+      id
+      state
+    }
+  }
+}",
+  "variables": null
+}
+_args_
+run_graphql_ok "${TEST_NAME}" "${WORKFLOW_NAME}" "${optionalBreak}"
+
+# stop workflow
+cylc stop --max-polls=10 --interval=2 --kill "${WORKFLOW_NAME}"
+
+RESPONSE="${TEST_NAME_BASE}-prune-optional-break.stdout"
+
+# compare to expectation
+cmp_json "${TEST_NAME}-out" "$RESPONSE" << __HERE__
+{
+    "workflows": [
+        {
+            "name": "${WORKFLOW_NAME}",
+            "taskProxies": [
+                {
+                    "id": "~${USER}/${WORKFLOW_NAME}//1/d",
+                    "state": "succeeded"
+                },
+                {
+                    "id": "~${USER}/${WORKFLOW_NAME}//1/e",
+                    "state": "waiting"
+                }
+            ]
+        }
+    ]
+}
+__HERE__
+
+purge

tests/functional/data-store/test_header

@@ -0,0 +1 @@
+../lib/bash/test_header