test: race coverage for list_definitions_for_child and list_active_definitions (F74-002)

Read definitions, rules, assignees and windows in one locked transaction via DAO snapshot-list methods so concurrent edits cannot interleave; re-raise edit's missing-definition error with a definition_id field prefix.

custom_components/nestquest/dao_rules.py

@@ -907,6 +907,66 @@ class QuestDefinitionsDao:
         )
         return [_definition_from_row(row) for row in rows]
 
+    async def _snapshots_for(
+        self, definitions: list[QuestDefinitionRecord]
+    ) -> list[QuestDefinitionSnapshot]:
+        """Read each definition's rule, assignees and windows.
+
+        MUST be called inside the connection lock (and ideally a
+        transaction) so the definitions handed in and the rows this
+        reads back cannot be raced by a concurrent edit between list
+        and bundle.  Each rule is read through
+        :class:`ScheduleRulesDao` on the same connection, so the
+        snapshot's rule record is the one the definition references AT
+        the moment of the locked read.
+        """
+        rules_dao = ScheduleRulesDao(self._database)
+        snapshots: list[QuestDefinitionSnapshot] = []
+        for definition in definitions:
+            rule_record = await rules_dao.get(definition.schedule_rule_id)
+            assert rule_record is not None
+            snapshots.append(
+                QuestDefinitionSnapshot(
+                    definition=definition,
+                    rule=rule_record,
+                    assignees=await self.list_assignees(definition.id),
+                    windows=await self.list_windows(definition.id),
+                )
+            )
+        return snapshots
+
+    async def list_snapshots_active(self) -> list[QuestDefinitionSnapshot]:
+        """Return every active definition with its rule, assignees and
+        windows, all read inside one locked transaction.
+
+        The definitive list and each definition's linked rows are read
+        in a single BEGIN..COMMIT span under the connection lock, so a
+        concurrent atomic edit cannot interleave between the definition
+        list and the bundle read: the caller receives a coherent
+        snapshot (each definition's rule, assignees and windows as they
+        were at one instant), never a mixed old-rule/new-windows state.
+        """
+        async with _connection_lock(self._database):
+            async with self._database.transaction():
+                definitions = await self.list_active()
+                return await self._snapshots_for(definitions)
+
+    async def list_snapshots_by_child(
+        self, child_id: int
+    ) -> list[QuestDefinitionSnapshot]:
+        """Return each definition assigned to ``child_id`` with its rule,
+        assignees and windows, all read inside one locked transaction.
+
+        Mirrors :meth:`list_snapshots_active` but selects by assignment
+        (``list_by_child`` order: newest first).  Locks read-and-bundle
+        into one transaction so the bundle never mixes one edit's
+        definition with another's windows.
+        """
+        async with _connection_lock(self._database):
+            async with self._database.transaction():
+                definitions = await self.list_by_child(child_id)
+                return await self._snapshots_for(definitions)
+
     async def update(
         self,
         definition_id: int,

custom_components/nestquest/quest_definitions.py

@@ -44,11 +44,13 @@ from dataclasses import dataclass
 from .dao_children import ChildRecord, _connection_lock
 from .dao_rules import (
     QuestDefinitionRecord,
+    QuestDefinitionSnapshot,
     QuestDefinitionWindowRecord,
     QuestDefinitionsDao,
     ScheduleRuleStorage,
     ScheduleRulesDao,
     _UNSET,
+    _validate_date,
     _validate_time,
     _validate_window,
     schedule_rule_from_storage,
@@ -56,7 +58,7 @@ from .dao_rules import (
     schedule_rule_to_storage,
 )
 from .db import NestQuestDatabase
-from .recurrence import ScheduleRule
+from .recurrence import ScheduleRule, occurs_on
 
 
 @dataclass(frozen=True)
@@ -317,6 +319,7 @@ async def edit_quest_definition(
         window_specs = _normalize_windows(windows)
 
     dao = QuestDefinitionsDao(database)
+    try:
         snapshot = await dao.edit_definition(
             definition_id,
             title=title_value,
@@ -325,6 +328,14 @@ async def edit_quest_definition(
             rule=rule_storage,
             windows=window_specs,
         )
+    except ValueError as error:
+        # The DAO's missing-definition error names only the id; re-raise
+        # so the public contract names the field the caller passed (matching
+        # assign/unassign/deactivate).
+        message = str(error)
+        if message.startswith("quest definition "):
+            raise ValueError(f"definition_id: {message}") from error
+        raise
 
     decoded_rule = schedule_rule_from_storage(
         schedule_rule_storage_from_record(snapshot.rule)
@@ -452,3 +463,89 @@ async def set_quest_definition_active(
         assignees=assignees,
         windows=windows,
     )
+
+
+def _bundle_snapshot(
+    snapshot: QuestDefinitionSnapshot,
+) -> CreatedQuestDefinition:
+    """Decode a DAO snapshot into the layer's rich view.
+
+    The rule record carried by the snapshot is the one the definition
+    referenced at read time, so decoding it here (rather than re-reading
+    through :class:`~.dao_rules.ScheduleRulesDao`) preserves the
+    coherence the DAO's locked snapshot guarantees: the rule, assignees
+    and windows all come from one atomic read, never three separate ones.
+    """
+    rule = schedule_rule_from_storage(
+        schedule_rule_storage_from_record(snapshot.rule)
+    )
+    return CreatedQuestDefinition(
+        definition=snapshot.definition,
+        rule=rule,
+        assignees=snapshot.assignees,
+        windows=snapshot.windows,
+    )
+
+
+async def list_active_definitions(
+    database: NestQuestDatabase,
+) -> list[CreatedQuestDefinition]:
+    """Return every ACTIVE definition with its decoded rule and links.
+
+    Ordered by rising definition id, matching the DAO's ``list_active``
+    order, so callers get a stable, repeatable sequence.  Each entry is
+    the same rich :class:`CreatedQuestDefinition` snapshot as the rest of
+    the layer: the stored row plus its decoded
+    :class:`~.recurrence.ScheduleRule`, assignees and windows.  The
+    definitions and their links are read by the DAO inside one locked
+    transaction, so each bundle is a coherent snapshot that a concurrent
+    edit cannot interleave.
+    """
+    dao = QuestDefinitionsDao(database)
+    snapshots = await dao.list_snapshots_active()
+    return [_bundle_snapshot(snapshot) for snapshot in snapshots]
+
+
+async def list_definitions_for_child(
+    database: NestQuestDatabase,
+    child_id: int,
+) -> list[CreatedQuestDefinition]:
+    """Return the definitions assigned to ``child_id`` (rich view).
+
+    ``child_id`` must be a plain int (bools and floats rejected, since
+    SQLite would bind ``True`` onto child 1).  Results are ordered by
+    rising definition id, matching ``list_active_definitions`` and
+    ``list_definitions_firing_on``.  Each entry is a
+    :class:`CreatedQuestDefinition` snapshot bundling the definition with
+    its decoded rule, assignees and windows, read atomically by the DAO.
+    """
+    _validate_child_id(child_id)
+    dao = QuestDefinitionsDao(database)
+    snapshots = await dao.list_snapshots_by_child(child_id)
+    bundles = [_bundle_snapshot(snapshot) for snapshot in snapshots]
+    return sorted(bundles, key=lambda bundle: bundle.definition.id)
+
+
+async def list_definitions_firing_on(
+    database: NestQuestDatabase,
+    date: str,
+) -> list[CreatedQuestDefinition]:
+    """Return the ACTIVE definitions whose rule fires on ``date``.
+
+    ``date`` must be a strict ISO calendar date (YYYY-MM-DD); a malformed
+    value raises ValueError naming the field.  Each active definition's
+    stored rule is decoded through the task-1 storage mapping and handed
+    to the recurrence engine's :func:`~.recurrence.occurs_on`; only the
+    definitions whose decoded rule fires on the date are returned, in
+    rising definition-id order, each as the same rich
+    :class:`CreatedQuestDefinition` snapshot as the rest of the layer.
+    The definitions and their rules are read inside one locked
+    transaction, so a bundle can never filter on one rule while
+    presenting another state's windows.
+    """
+    _validate_date(date, "date")
+    target = datetime.datetime.strptime(date, "%Y-%m-%d").date()
+    dao = QuestDefinitionsDao(database)
+    snapshots = await dao.list_snapshots_active()
+    bundles = [_bundle_snapshot(snapshot) for snapshot in snapshots]
+    return [bundle for bundle in bundles if occurs_on(bundle.rule, target)]

tests/test_quest_definitions.py

@@ -24,6 +24,9 @@ from custom_components.nestquest.quest_definitions import (
     assign_child,
     create_quest_definition,
     edit_quest_definition,
+    list_active_definitions,
+    list_definitions_firing_on,
+    list_definitions_for_child,
     set_quest_definition_active,
     unassign_child,
 )
@@ -783,6 +786,24 @@ def test_edit_rejects_nonexistent_definition(tmp_path) -> None:
     _with_db(tmp_path, "edit-missing-definition.db")(_body)
 
 
+def test_edit_nonexistent_definition_names_field(tmp_path) -> None:
+    """A missing definition's error names the ``definition_id`` field.
+
+    The DAO raises a bare "quest definition <id> does not exist"; the
+    business layer must re-raise it prefixed with the field the caller
+    passed, matching assign/unassign/deactivate.
+    """
+    async def _body(database, children, rules, definitions, child):
+        with pytest.raises(
+            ValueError,
+            match="definition_id: quest definition 999 does not exist",
+        ):
+            await edit_quest_definition(database, 999, title="X")
+        return None
+
+    _with_db(tmp_path, "edit-missing-definition-field.db")(_body)
+
+
 @pytest.mark.parametrize("bad", [True, 1.5, "1", None])
 def test_edit_rejects_non_int_definition_id(tmp_path, bad) -> None:
     async def _body(database, children, rules, definitions, child):
@@ -1420,3 +1441,506 @@ def test_set_quest_definition_active_concurrent_opposite_transitions_return_own(
             await database.close()
 
     _run(_main())
+
+
+# ---------------------------------------------------------------------------
+# list query helpers: list_active_definitions / list_definitions_for_child /
+# list_definitions_firing_on
+# ---------------------------------------------------------------------------
+
+
+def test_list_active_definitions_returns_only_active_in_id_order(tmp_path) -> None:
+    """Only active definitions come back, in rising id order, each rich.
+
+    Two definitions are created (ids 1 and 2), then definition 1 is
+    deactivated.  ``list_active_definitions`` must return only definition
+    2, and every bundle must carry the decoded rule, assignees and
+    windows of its own definition.
+    """
+    async def _body(database, children, rules, definitions, child):
+        bo = await children.create("Bo", NOW)
+        first = await create_quest_definition(
+            database, "Brush teeth", _daily_rule(), [child.id], ["morning"]
+        )
+        weekly = ScheduleRule(
+            rule_type=RuleType.WEEKLY,
+            weekday_set={0, 2},
+            start_date="2026-09-14",
+        )
+        second = await create_quest_definition(
+            database,
+            "Tidy room",
+            weekly,
+            [child.id, bo.id],
+            [("morning", "08:00"), ("evening", "19:00")],
+        )
+        assert [d.id for d in await definitions.list_active()] == [
+            first.definition.id,
+            second.definition.id,
+        ]
+
+        await set_quest_definition_active(database, first.definition.id, False)
+
+        result = await list_active_definitions(database)
+        assert [bundle.definition.id for bundle in result] == [second.definition.id]
+        assert isinstance(result[0], CreatedQuestDefinition)
+        assert result[0].rule == weekly
+        assert sorted(c.id for c in result[0].assignees) == sorted(
+            [child.id, bo.id]
+        )
+        by_name = {w.window: w.due_time for w in result[0].windows}
+        assert by_name == {"morning": "08:00", "evening": "19:00"}
+        return result
+
+    _with_db(tmp_path, "list-active.db")(_body)
+
+
+def test_list_definitions_for_child_returns_only_that_child(tmp_path) -> None:
+    """Only the given child's definitions come back, deterministically.
+
+    Definitions are created assigned to Ada (child), Bo, or both; the
+    helper must return exactly the definitions assigned to Ada, excluding
+    a Bo-only definition.  Inactive definitions are still assigned, so
+    they too come back (the helper filters by child, not by activity).
+    """
+    async def _body(database, children, rules, definitions, child):
+        bo = await children.create("Bo", NOW)
+        ada_only = await create_quest_definition(
+            database, "Brush teeth", _daily_rule(), [child.id], ["morning"]
+        )
+        both = await create_quest_definition(
+            database,
+            "Tidy room",
+            ScheduleRule(
+                rule_type=RuleType.WEEKLY,
+                weekday_set={1},
+                start_date="2026-09-14",
+            ),
+            [child.id, bo.id],
+            ["evening"],
+        )
+        bo_only = await create_quest_definition(
+            database, "Walk dog", _daily_rule(), [bo.id], ["afternoon"]
+        )
+
+        # The helper returns the given child's definitions in ascending
+        # id order, consistent with list_active_definitions.
+        result = await list_definitions_for_child(database, child.id)
+        assert [bundle.definition.id for bundle in result] == [
+            ada_only.definition.id,
+            both.definition.id,
+        ]
+        assert result[0].rule == _daily_rule()
+        assert [c.id for c in result[0].assignees] == [child.id]
+        assert [w.window for w in result[0].windows] == ["morning"]
+
+        bo_result = await list_definitions_for_child(database, bo.id)
+        assert [bundle.definition.id for bundle in bo_result] == [
+            both.definition.id,
+            bo_only.definition.id,
+        ]
+        return result
+
+    _with_db(tmp_path, "list-for-child.db")(_body)
+
+
+@pytest.mark.parametrize("bad", [True, False, 1.5, "1", None])
+def test_list_definitions_for_child_rejects_non_int_child_id(tmp_path, bad) -> None:
+    async def _body(database, children, rules, definitions, child):
+        with pytest.raises(ValueError, match="child_id must be an integer"):
+            await list_definitions_for_child(database, bad)
+        return None
+
+    _with_db(tmp_path, "list-for-child-bad-id.db")(_body)
+
+
+def test_list_definitions_firing_on_mixed_rules(tmp_path) -> None:
+    """A mixed daily + weekly + monthly set fires on the right dates.
+
+    Daily fires every day from its start; weekly fires on its weekdays;
+    monthly fires on its day-of-month.  Deactivated definitions never
+    fire, and the returned bundles carry the decoded rule.
+    """
+    async def _body(database, children, rules, definitions, child):
+        daily = await create_quest_definition(
+            database,
+            "Daily chore",
+            ScheduleRule(rule_type=RuleType.DAILY, start_date="2026-09-14"),
+            [child.id],
+            ["morning"],
+        )
+        weekly = await create_quest_definition(
+            database,
+            "Weekly chore",
+            ScheduleRule(
+                rule_type=RuleType.WEEKLY,
+                weekday_set={0, 2},  # Monday, Wednesday
+                start_date="2026-09-14",
+            ),
+            [child.id],
+            ["evening"],
+        )
+        monthly = await create_quest_definition(
+            database,
+            "Monthly chore",
+            ScheduleRule(
+                rule_type=RuleType.MONTHLY_DAY,
+                day_of_month=15,
+                start_date="2026-09-14",
+            ),
+            [child.id],
+            ["afternoon"],
+        )
+
+        # 2026-09-14 is a Monday (weekday 0): daily + weekly fire;
+        # monthly (the 15th) does not.
+        hits = await list_definitions_firing_on(database, "2026-09-14")
+        assert [b.definition.id for b in hits] == [
+            daily.definition.id,
+            weekly.definition.id,
+        ]
+        # 2026-09-15 is a Tuesday (weekday 1, day 15): daily + monthly.
+        hits = await list_definitions_firing_on(database, "2026-09-15")
+        assert [b.definition.id for b in hits] == [
+            daily.definition.id,
+            monthly.definition.id,
+        ]
+        # 2026-09-16 is a Wednesday (weekday 2, day 16): daily + weekly.
+        hits = await list_definitions_firing_on(database, "2026-09-16")
+        assert [b.definition.id for b in hits] == [
+            daily.definition.id,
+            weekly.definition.id,
+        ]
+
+        # Deactivating a definition removes it from every future result.
+        await set_quest_definition_active(database, weekly.definition.id, False)
+        hits = await list_definitions_firing_on(database, "2026-09-14")
+        assert [b.definition.id for b in hits] == [daily.definition.id]
+        # The returned bundle carries the decoded rule, not the raw row.
+        assert hits[0].rule == ScheduleRule(
+            rule_type=RuleType.DAILY, start_date="2026-09-14"
+        )
+        return hits
+
+    _with_db(tmp_path, "list-firing-on.db")(_body)
+
+
+@pytest.mark.parametrize(
+    "bad",
+    ["2026-9-4", "2026-13-01", "2026-02-30", "not-a-date", None, 20260914],
+)
+def test_list_definitions_firing_on_rejects_malformed_date(tmp_path, bad) -> None:
+    async def _body(database, children, rules, definitions, child):
+        await create_quest_definition(
+            database, "Brush teeth", _daily_rule(), [child.id], ["morning"]
+        )
+        with pytest.raises(ValueError, match="date must be"):
+            await list_definitions_firing_on(database, bad)
+        return None
+
+    _with_db(tmp_path, "list-firing-on-bad-date.db")(_body)
+
+
+def test_list_query_snapshot_coherent_under_racing_edit(tmp_path) -> None:
+    """A racing edit cannot mix states into a query helper's snapshot.
+
+    The query helper pauses mid-snapshot (inside its locked transaction)
+    while an edit that changes BOTH the rule and the windows is queued
+    behind the connection lock.  Because the helper reads definitions,
+    rules and windows in one locked transaction, its returned bundle is
+    either the whole old state or the whole new state — never the old
+    rule paired with the new windows (the exact interleaving the unlocked
+    reads used to allow).  The pause hook holds
+    ``list_windows`` mid-flight so the edit is deterministically queued
+    against the helper's lock.
+    """
+    async def _body(database, children, rules, definitions, child):
+        created = await create_quest_definition(
+            database, "Brush teeth", _daily_rule(), [child.id], ["morning"]
+        )
+        weekly = ScheduleRule(
+            rule_type=RuleType.WEEKLY,
+            weekday_set={2},
+            start_date="2026-09-14",
+        )
+
+        import custom_components.nestquest.dao_rules as dao_rules
+
+        original_list = dao_rules.QuestDefinitionsDao.list_windows
+        started = asyncio.Event()
+        release = asyncio.Event()
+
+        async def _pausing_list(self, definition_id):
+            if not started.is_set():
+                started.set()
+                await release.wait()
+            return await original_list(self, definition_id)
+
+        dao_rules.QuestDefinitionsDao.list_windows = _pausing_list
+        try:
+            read_task = asyncio.ensure_future(
+                list_definitions_firing_on(database, "2026-09-16")
+            )
+            await started.wait()
+            edit_task = asyncio.ensure_future(
+                edit_quest_definition(
+                    database,
+                    created.definition.id,
+                    rule=weekly,
+                    windows=["evening"],
+                )
+            )
+            await asyncio.sleep(0)
+            release.set()
+            result, edited = await asyncio.gather(read_task, edit_task)
+        finally:
+            dao_rules.QuestDefinitionsDao.list_windows = original_list
+
+        # The helper finished before the queued edit, so its snapshot is
+        # the whole OLD state: the daily rule with its morning window.
+        assert [b.definition.id for b in result] == [created.definition.id]
+        assert result[0].rule == _daily_rule()
+        assert [w.window for w in result[0].windows] == ["morning"]
+        # The edit then reported the whole NEW state, not a mix either.
+        assert edited.rule == weekly
+        assert [w.window for w in edited.windows] == ["evening"]
+        return result
+
+    _with_db(tmp_path, "list-snapshot-concurrent.db")(_body)
+
+
+def test_list_definitions_for_child_snapshot_coherent_under_racing_unassign(
+    tmp_path,
+) -> None:
+    """A racing unassign cannot strip the child from the child-scoped
+    snapshot that ``list_definitions_for_child`` returns.
+
+    The helper pauses mid-snapshot (inside its locked transaction) while
+    an unassign of the very child it is listing is queued behind the
+    connection lock.  Because the definition set and its assignees are
+    read in one locked transaction, the returned bundle still shows the
+    child assigned — the coherent pre-unassign snapshot — rather than the
+    mixed state (definition returned "for child" but with the child
+    already gone from its roster) that the unlocked reads used to allow.
+    The pause hook holds ``list_assignees`` mid-flight so the unassign is
+    deterministically queued against the helper's lock.
+    """
+    async def _body(database, children, rules, definitions, child):
+        created = await create_quest_definition(
+            database, "Brush teeth", _daily_rule(), [child.id], ["morning"]
+        )
+
+        import custom_components.nestquest.dao_rules as dao_rules
+
+        original_list = dao_rules.QuestDefinitionsDao.list_assignees
+        started = asyncio.Event()
+        release = asyncio.Event()
+
+        async def _pausing_list(self, definition_id):
+            if not started.is_set():
+                started.set()
+                await release.wait()
+            return await original_list(self, definition_id)
+
+        dao_rules.QuestDefinitionsDao.list_assignees = _pausing_list
+        try:
+            read_task = asyncio.ensure_future(
+                list_definitions_for_child(database, child.id)
+            )
+            await started.wait()
+            unassign_task = asyncio.ensure_future(
+                unassign_child(database, created.definition.id, child.id)
+            )
+            for _ in range(5):
+                await asyncio.sleep(0)
+            release.set()
+            result, removed = await asyncio.gather(read_task, unassign_task)
+        finally:
+            dao_rules.QuestDefinitionsDao.list_assignees = original_list
+
+        # The helper finished before the queued unassign, so its snapshot
+        # is the whole OLD state: the child still assigned to the
+        # definition it returned for that child.
+        assert [b.definition.id for b in result] == [created.definition.id]
+        assert [c.id for c in result[0].assignees] == [child.id]
+        assert removed is True
+        return result
+
+    _with_db(tmp_path, "list-for-child-snapshot-concurrent.db")(_body)
+
+
+def test_list_active_definitions_snapshot_coherent_under_racing_edit(
+    tmp_path,
+) -> None:
+    """A racing edit cannot mix states into ``list_active_definitions``.
+
+    The helper pauses mid-snapshot (inside its locked transaction) while
+    an edit that changes BOTH the rule and the windows is queued behind
+    the connection lock.  Because definitions, rules and windows are read
+    in one locked transaction, the returned bundle is the whole old state
+    — the daily rule with its morning window — never the old rule paired
+    with the new windows.  The pause hook holds ``list_windows``
+    mid-flight so the edit is deterministically queued against the
+    helper's lock.
+    """
+    async def _body(database, children, rules, definitions, child):
+        created = await create_quest_definition(
+            database, "Brush teeth", _daily_rule(), [child.id], ["morning"]
+        )
+        weekly = ScheduleRule(
+            rule_type=RuleType.WEEKLY,
+            weekday_set={2},
+            start_date="2026-09-14",
+        )
+
+        import custom_components.nestquest.dao_rules as dao_rules
+
+        original_list = dao_rules.QuestDefinitionsDao.list_windows
+        started = asyncio.Event()
+        release = asyncio.Event()
+
+        async def _pausing_list(self, definition_id):
+            if not started.is_set():
+                started.set()
+                await release.wait()
+            return await original_list(self, definition_id)
+
+        dao_rules.QuestDefinitionsDao.list_windows = _pausing_list
+        try:
+            read_task = asyncio.ensure_future(list_active_definitions(database))
+            await started.wait()
+            edit_task = asyncio.ensure_future(
+                edit_quest_definition(
+                    database,
+                    created.definition.id,
+                    rule=weekly,
+                    windows=["evening"],
+                )
+            )
+            await asyncio.sleep(0)
+            release.set()
+            result, edited = await asyncio.gather(read_task, edit_task)
+        finally:
+            dao_rules.QuestDefinitionsDao.list_windows = original_list
+
+        # The helper finished before the queued edit, so its snapshot is
+        # the whole OLD state: the daily rule with its morning window.
+        assert [b.definition.id for b in result] == [created.definition.id]
+        assert result[0].rule == _daily_rule()
+        assert [w.window for w in result[0].windows] == ["morning"]
+        # The edit then reported the whole NEW state, not a mix either.
+        assert edited.rule == weekly
+        assert [w.window for w in edited.windows] == ["evening"]
+        return result
+
+    _with_db(tmp_path, "list-active-snapshot-concurrent.db")(_body)
+
+
+# ---------------------------------------------------------------------------
+# full-lifecycle integration: one definition through every operation
+# ---------------------------------------------------------------------------
+
+
+def test_full_lifecycle_never_touches_instances_or_history(tmp_path) -> None:
+    """End-to-end lifecycle on one definition writes only the four
+    definition tables; ``quest_instances`` and ``completion_events`` are
+    left exactly as they were at every stage.
+
+    A real instance and completion event are seeded before the lifecycle
+    begins, so each stage is checked against pre-existing data being
+    mutated (not an empty table staying empty): create -> edit
+    rule/windows -> assign a second child -> unassign the original child
+    -> deactivate -> reactivate.
+    """
+    async def _body(database, children, rules, definitions, child):
+        created = await create_quest_definition(
+            database,
+            "Brush teeth",
+            _daily_rule(),
+            [child.id],
+            [("morning", "07:00")],
+        )
+        definition_id = created.definition.id
+
+        instances = QuestInstancesDao(database)
+        events = CompletionEventsDao(database)
+        instance = await instances.upsert(
+            definition_id, child.id, _today_iso(), NOW, window="morning"
+        )
+        event = await events.append(
+            instance.id,
+            child.id,
+            "completed",
+            "user",
+            NOW,
+            True,
+            actor_user_id="admin-1",
+        )
+        instance_count = await database.fetch_one(
+            "SELECT COUNT(*) FROM quest_instances"
+        )
+        event_count = await database.fetch_one(
+            "SELECT COUNT(*) FROM completion_events"
+        )
+
+        async def _assert_history_untouched():
+            assert await instances.get_by_id(instance.id) == instance
+            assert await events.list_by_instance(instance.id) == [event]
+            assert await database.fetch_one(
+                "SELECT COUNT(*) FROM quest_instances"
+            ) == instance_count
+            assert await database.fetch_one(
+                "SELECT COUNT(*) FROM completion_events"
+            ) == event_count
+
+        await _assert_history_untouched()
+
+        # Edit rule and windows together; the definition's rule row is
+        # rewritten in place and its window set replaced.
+        edited = await edit_quest_definition(
+            database,
+            definition_id,
+            rule=ScheduleRule(
+                rule_type=RuleType.WEEKLY,
+                weekday_set={1, 3},
+                start_date="2026-09-14",
+            ),
+            windows=[("morning", "08:00"), ("evening", "19:30")],
+        )
+        assert edited.rule == ScheduleRule(
+            rule_type=RuleType.WEEKLY,
+            weekday_set={1, 3},
+            start_date="2026-09-14",
+        )
+        by_name = {w.window: w.due_time for w in edited.windows}
+        assert by_name == {"morning": "08:00", "evening": "19:30"}
+        await _assert_history_untouched()
+
+        # Assign a second child: multi-assignee, both present.
+        bo = await children.create("Bo", NOW)
+        roster = await assign_child(database, definition_id, bo.id)
+        assert sorted(c.id for c in roster) == sorted([child.id, bo.id])
+        await _assert_history_untouched()
+
+        # Unassign the original child: only the link drops.
+        assert await unassign_child(database, definition_id, child.id) is True
+        assert [
+            c.id for c in await definitions.list_assignees(definition_id)
+        ] == [bo.id]
+        await _assert_history_untouched()
+
+        # Deactivate, then reactivate: the definition survives both.
+        deactivated = await set_quest_definition_active(
+            database, definition_id, False
+        )
+        assert deactivated.definition.is_active is False
+        await _assert_history_untouched()
+        reactivated = await set_quest_definition_active(
+            database, definition_id, True
+        )
+        assert reactivated.definition.is_active is True
+        await _assert_history_untouched()
+
+        return reactivated
+
+    _with_db(tmp_path, "full-lifecycle.db")(_body)