Update relations after every decryption attempt (#2387)

* Update relations after every decryption attempt

If an event is encrypted the aggregation cannot pick up the relation types.
Before this change there was exactly one aggregation retry after decryption.
If the events are being decrypted afterwards (for example on restore
from key backup) the aggregation was not aware of that.
This change adds relation updates after every decryption event if there
has been a decryption error.

Signed-off-by: Michael Weimann <michaelw@matrix.org>

spec/unit/event-timeline-set.spec.ts

@@ -0,0 +1,154 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import * as utils from "../test-utils/test-utils";
+import {
+    EventTimeline,
+    EventTimelineSet,
+    EventType,
+    MatrixClient,
+    MatrixEvent,
+    MatrixEventEvent,
+    Room,
+} from '../../src';
+
+describe('EventTimelineSet', () => {
+    const roomId = '!foo:bar';
+    const userA = "@alice:bar";
+
+    let room: Room;
+    let eventTimeline: EventTimeline;
+    let eventTimelineSet: EventTimelineSet;
+    let client: MatrixClient;
+
+    let messageEvent: MatrixEvent;
+    let replyEvent: MatrixEvent;
+
+    const itShouldReturnTheRelatedEvents = () => {
+        it('should return the related events', () => {
+            eventTimelineSet.aggregateRelations(messageEvent);
+            const relations = eventTimelineSet.getRelationsForEvent(
+                messageEvent.getId(),
+                "m.in_reply_to",
+                EventType.RoomMessage,
+            );
+            expect(relations).toBeDefined();
+            expect(relations.getRelations().length).toBe(1);
+            expect(relations.getRelations()[0].getId()).toBe(replyEvent.getId());
+        });
+    };
+
+    beforeEach(() => {
+        client = utils.mock(MatrixClient, 'MatrixClient');
+        room = new Room(roomId, client, userA);
+        eventTimelineSet = new EventTimelineSet(room, {
+            unstableClientRelationAggregation: true,
+        });
+        eventTimeline = new EventTimeline(eventTimelineSet);
+        messageEvent = utils.mkMessage({
+            room: roomId,
+            user: userA,
+            msg: 'Hi!',
+            event: true,
+        }) as MatrixEvent;
+        replyEvent = utils.mkReplyMessage({
+            room: roomId,
+            user: userA,
+            msg: 'Hoo!',
+            event: true,
+            replyToMessage: messageEvent,
+        }) as MatrixEvent;
+    });
+
+    describe('aggregateRelations', () => {
+        describe('with unencrypted events', () => {
+            beforeEach(() => {
+                eventTimelineSet.addEventsToTimeline(
+                    [
+                        messageEvent,
+                        replyEvent,
+                    ],
+                    true,
+                    eventTimeline,
+                    'foo',
+                );
+            });
+
+            itShouldReturnTheRelatedEvents();
+        });
+
+        describe('with events to be decrypted', () => {
+            let messageEventShouldAttemptDecryptionSpy: jest.SpyInstance;
+            let messageEventIsDecryptionFailureSpy: jest.SpyInstance;
+
+            let replyEventShouldAttemptDecryptionSpy: jest.SpyInstance;
+            let replyEventIsDecryptionFailureSpy: jest.SpyInstance;
+
+            beforeEach(() => {
+                messageEventShouldAttemptDecryptionSpy = jest.spyOn(messageEvent, 'shouldAttemptDecryption');
+                messageEventShouldAttemptDecryptionSpy.mockReturnValue(true);
+                messageEventIsDecryptionFailureSpy = jest.spyOn(messageEvent, 'isDecryptionFailure');
+
+                replyEventShouldAttemptDecryptionSpy = jest.spyOn(replyEvent, 'shouldAttemptDecryption');
+                replyEventShouldAttemptDecryptionSpy.mockReturnValue(true);
+                replyEventIsDecryptionFailureSpy = jest.spyOn(messageEvent, 'isDecryptionFailure');
+
+                eventTimelineSet.addEventsToTimeline(
+                    [
+                        messageEvent,
+                        replyEvent,
+                    ],
+                    true,
+                    eventTimeline,
+                    'foo',
+                );
+            });
+
+            it('should not return the related events', () => {
+                eventTimelineSet.aggregateRelations(messageEvent);
+                const relations = eventTimelineSet.getRelationsForEvent(
+                    messageEvent.getId(),
+                    "m.in_reply_to",
+                    EventType.RoomMessage,
+                );
+                expect(relations).toBeUndefined();
+            });
+
+            describe('after decryption', () => {
+                beforeEach(() => {
+                    // simulate decryption failure once
+                    messageEventIsDecryptionFailureSpy.mockReturnValue(true);
+                    replyEventIsDecryptionFailureSpy.mockReturnValue(true);
+
+                    messageEvent.emit(MatrixEventEvent.Decrypted, messageEvent);
+                    replyEvent.emit(MatrixEventEvent.Decrypted, replyEvent);
+
+                    // simulate decryption
+                    messageEventIsDecryptionFailureSpy.mockReturnValue(false);
+                    replyEventIsDecryptionFailureSpy.mockReturnValue(false);
+
+                    messageEventShouldAttemptDecryptionSpy.mockReturnValue(false);
+                    replyEventShouldAttemptDecryptionSpy.mockReturnValue(false);
+
+                    messageEvent.emit(MatrixEventEvent.Decrypted, messageEvent);
+                    replyEvent.emit(MatrixEventEvent.Decrypted, replyEvent);
+                });
+
+                itShouldReturnTheRelatedEvents();
+            });
+        });
+    });
+});