Prepare utils for local rooms (#9084)

* Prepare utils for local rooms

* Split up direct-messages module

test/utils/dm/createDmLocalRoom-test.ts

@@ -0,0 +1,114 @@
+/*
+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 { mocked } from "jest-mock";
+import { EventType, KNOWN_SAFE_ROOM_VERSION, MatrixClient } from "matrix-js-sdk/src/matrix";
+
+import { canEncryptToAllUsers } from "../../../src/createRoom";
+import { LocalRoom, LOCAL_ROOM_ID_PREFIX } from "../../../src/models/LocalRoom";
+import { DirectoryMember, Member, ThreepidMember } from "../../../src/utils/direct-messages";
+import { createDmLocalRoom } from "../../../src/utils/dm/createDmLocalRoom";
+import { privateShouldBeEncrypted } from "../../../src/utils/rooms";
+import { createTestClient } from "../../test-utils";
+
+jest.mock("../../../src/utils/rooms", () => ({
+    privateShouldBeEncrypted: jest.fn(),
+}));
+
+jest.mock("../../../src/createRoom", () => ({
+    canEncryptToAllUsers: jest.fn(),
+}));
+
+function assertLocalRoom(room: LocalRoom, targets: Member[], encrypted: boolean) {
+    expect(room.roomId).toBe(LOCAL_ROOM_ID_PREFIX + "t1");
+    expect(room.name).toBe(targets.length ? targets[0].name : "Empty Room");
+    expect(room.encrypted).toBe(encrypted);
+    expect(room.targets).toEqual(targets);
+    expect(room.getMyMembership()).toBe("join");
+
+    const roomCreateEvent = room.currentState.getStateEvents(EventType.RoomCreate)[0];
+    expect(roomCreateEvent).toBeDefined();
+    expect(roomCreateEvent.getContent()["room_version"]).toBe(KNOWN_SAFE_ROOM_VERSION);
+
+    // check that the user and all targets are joined
+    expect(room.getMember("@userId:matrix.org").membership).toBe("join");
+    targets.forEach((target: Member) => {
+        expect(room.getMember(target.userId).membership).toBe("join");
+    });
+
+    if (encrypted) {
+        const encryptionEvent = room.currentState.getStateEvents(EventType.RoomEncryption)[0];
+        expect(encryptionEvent).toBeDefined();
+    }
+}
+
+describe("createDmLocalRoom", () => {
+    let mockClient: MatrixClient;
+    const userId1 = "@user1:example.com";
+    const member1 = new DirectoryMember({ user_id: userId1 });
+    const member2 = new ThreepidMember("user2");
+
+    beforeEach(() => {
+        mockClient = createTestClient();
+    });
+
+    describe("when rooms should be encrypted", () => {
+        beforeEach(() => {
+            mocked(privateShouldBeEncrypted).mockReturnValue(true);
+        });
+
+        it("should create an unencrypted room for 3PID targets", async () => {
+            const room = await createDmLocalRoom(mockClient, [member2]);
+            expect(mockClient.store.storeRoom).toHaveBeenCalledWith(room);
+            assertLocalRoom(room, [member2], false);
+        });
+
+        describe("for MXID targets with encryption available", () => {
+            beforeEach(() => {
+                mocked(canEncryptToAllUsers).mockResolvedValue(true);
+            });
+
+            it("should create an encrypted room", async () => {
+                const room = await createDmLocalRoom(mockClient, [member1]);
+                expect(mockClient.store.storeRoom).toHaveBeenCalledWith(room);
+                assertLocalRoom(room, [member1], true);
+            });
+        });
+
+        describe("for MXID targets with encryption unavailable", () => {
+            beforeEach(() => {
+                mocked(canEncryptToAllUsers).mockResolvedValue(false);
+            });
+
+            it("should create an unencrypted room", async () => {
+                const room = await createDmLocalRoom(mockClient, [member1]);
+                expect(mockClient.store.storeRoom).toHaveBeenCalledWith(room);
+                assertLocalRoom(room, [member1], false);
+            });
+        });
+    });
+
+    describe("if rooms should not be encrypted", () => {
+        beforeEach(() => {
+            mocked(privateShouldBeEncrypted).mockReturnValue(false);
+        });
+
+        it("should create an unencrypted room", async () => {
+            const room = await createDmLocalRoom(mockClient, [member1]);
+            assertLocalRoom(room, [member1], false);
+        });
+    });
+});