Apply strictNullChecks to src/components/views/rooms/* (#10875)

* fix everything except notificationbadge

* unit test ThirdPartyMemberInfo

* fix RoomPreviewBar dm tests

* lint

* test PinnedEventTile

test/components/views/rooms/ThirdPartyMemberInfo-test.tsx

@@ -0,0 +1,75 @@
+/*
+Copyright 2023 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 React from "react";
+import { render, screen } from "@testing-library/react";
+import { EventType, IEvent, MatrixEvent, Room, RoomMember } from "matrix-js-sdk/src/matrix";
+
+import ThirdPartyMemberInfo from "../../../../src/components/views/rooms/ThirdPartyMemberInfo";
+import { getMockClientWithEventEmitter, mockClientMethodsUser } from "../../../test-utils";
+
+describe("<ThirdPartyMemberInfo />", () => {
+    const userId = "@alice:server.org";
+    const roomId = "!room:server.org";
+    const mockClient = getMockClientWithEventEmitter({
+        ...mockClientMethodsUser(userId),
+        getRoom: jest.fn(),
+    });
+
+    // make invite event with defaults
+    const makeInviteEvent = (props: Partial<IEvent> = {}): MatrixEvent =>
+        new MatrixEvent({
+            type: EventType.RoomThirdPartyInvite,
+            state_key: "123456",
+            sender: userId,
+            room_id: roomId,
+            content: {
+                display_name: "bob@bob.com",
+                key_validity_url: "https://isthiskeyvalid.org",
+                public_key: "abc123",
+            },
+            ...props,
+        });
+    const defaultEvent = makeInviteEvent();
+
+    const getComponent = (event: MatrixEvent = defaultEvent) => render(<ThirdPartyMemberInfo event={event} />);
+    const room = new Room(roomId, mockClient, userId);
+    const aliceMember = new RoomMember(roomId, userId);
+    aliceMember.name = "Alice DisplayName";
+
+    beforeEach(() => {
+        jest.spyOn(room, "getMember").mockImplementation((id) => (id === userId ? aliceMember : null));
+        mockClient.getRoom.mockClear().mockReturnValue(room);
+    });
+
+    it("should render invite", () => {
+        const { container } = getComponent();
+        expect(container).toMatchSnapshot();
+    });
+
+    it("should render invite when room in not available", () => {
+        const event = makeInviteEvent({ room_id: "not_available" });
+        const { container } = getComponent(event);
+        expect(container).toMatchSnapshot();
+    });
+
+    it("should use inviter's id when room member is not available", () => {
+        const event = makeInviteEvent({ sender: "@charlie:server.org" });
+        getComponent(event);
+
+        expect(screen.getByText("Invited by @charlie:server.org")).toBeInTheDocument();
+    });
+});