ops 2.10 relation broken behaviour fix

README.md

@@ -419,10 +419,9 @@ state_in = State(relations=[
     PeerRelation(
         endpoint="peers",
         peers_data={1: {}, 2: {}, 42: {'foo': 'bar'}},
-    )],
-    unit_id=1)
+    )])
 
-Context(...).run("start", state_in)  # invalid: this unit's id cannot be the ID of a peer.
+Context(..., unit_id=1).run("start", state_in)  # invalid: this unit's id cannot be the ID of a peer.
 
 
 ```

pyproject.toml

@@ -8,7 +8,7 @@ build-backend = "setuptools.build_meta"
 [project]
 name = "ops-scenario"
 
-version = "6.0"
+version = "6.0.1"
 
 authors = [
     { name = "Pietro Pasotti", email = "[email protected]" }

scenario/ops_main_mock.py

@@ -109,7 +109,13 @@ def setup_framework(
         actions_metadata = None
 
     meta = CharmMeta.from_yaml(metadata, actions_metadata)
-    model = ops.model.Model(meta, model_backend)
+
+    # If we are in a RelationBroken event, we want to know which relation is
+    # broken within the model, not only in the event's `.relation` attribute.
+    broken_relation_id = (
+        event.relation.relation_id if event.name.endswith("_relation_broken") else None  # type: ignore
+    )
+    model = ops.model.Model(meta, model_backend, broken_relation_id=broken_relation_id)
 
     charm_state_path = charm_dir / CHARM_STATE_FILE
 

tests/test_e2e/test_relations.py

@@ -1,9 +1,16 @@
 from typing import Type
 
 import pytest
-from ops.charm import CharmBase, CharmEvents, CollectStatusEvent, RelationDepartedEvent
+from ops.charm import (
+    CharmBase,
+    CharmEvents,
+    CollectStatusEvent,
+    RelationDepartedEvent,
+    RelationEvent,
+)
 from ops.framework import EventBase, Framework
 
+from scenario import Context
 from scenario.state import (
     PeerRelation,
     Relation,
@@ -115,8 +122,15 @@ def test_relation_events(mycharm, evt_name, remote_app_name):
         endpoint="foo", interface="foo", remote_app_name=remote_app_name
     )
 
-    def callback(charm: CharmBase, _):
-        assert charm.model.get_relation("foo").app.name == remote_app_name
+    def callback(charm: CharmBase, e):
+        if not isinstance(e, RelationEvent):
+            return  # filter out collect status events
+
+        if evt_name == "broken":
+            assert charm.model.get_relation("foo") is None
+            assert e.relation.app.name == remote_app_name
+        else:
+            assert charm.model.get_relation("foo").app.name == remote_app_name
 
     mycharm._call = callback
 
@@ -357,3 +371,15 @@ def test_relation_ids():
     for i in range(10):
         rel = Relation("foo")
         assert rel.relation_id == initial_id + i
+
+
+def test_broken_relation_not_in_model_relations(mycharm):
+    rel = Relation("foo")
+
+    with Context(
+        mycharm, meta={"name": "local", "requires": {"foo": {"interface": "foo"}}}
+    ).manager(rel.broken_event, state=State(relations=[rel])) as mgr:
+        charm = mgr.charm
+
+        assert charm.model.get_relation("foo") is None
+        assert charm.model.relations["foo"] == []