Conform more of the code base to strict null checking (#10147)

* Conform more of the code base to strict null checking

* More strict fixes

* More strict work

* Fix missing optional type

* Iterate

src/hooks/room/useTopic.ts

@@ -26,11 +26,11 @@ import { Optional } from "matrix-events-sdk";
 import { useTypedEventEmitter } from "../useEventEmitter";
 
 export const getTopic = (room: Room): Optional<TopicState> => {
-    const content: MRoomTopicEventContent = room?.currentState?.getStateEvents(EventType.RoomTopic, "")?.getContent();
+    const content = room?.currentState?.getStateEvents(EventType.RoomTopic, "")?.getContent<MRoomTopicEventContent>();
     return !!content ? parseTopicContent(content) : null;
 };
 
-export function useTopic(room: Room): TopicState {
+export function useTopic(room: Room): Optional<TopicState> {
     const [topic, setTopic] = useState(getTopic(room));
     useTypedEventEmitter(room.currentState, RoomStateEvent.Events, (ev: MatrixEvent) => {
         if (ev.getType() !== EventType.RoomTopic) return;

src/hooks/spotlight/useRecentSearches.ts

@@ -25,7 +25,7 @@ export const useRecentSearches = (): [Room[], () => void] => {
     const [rooms, setRooms] = useState(() => {
         const cli = MatrixClientPeg.get();
         const recents = SettingsStore.getValue<string[]>("SpotlightSearch.recentSearches", null);
-        return recents.map((r) => cli.getRoom(r)).filter(Boolean);
+        return recents.map((r) => cli.getRoom(r)).filter(Boolean) as Room[];
     });
 
     return [

src/hooks/useAccountData.ts

@@ -21,11 +21,11 @@ import { Room, RoomEvent } from "matrix-js-sdk/src/models/room";
 
 import { useTypedEventEmitter } from "./useEventEmitter";
 
-const tryGetContent = <T extends {}>(ev?: MatrixEvent): T => (ev ? ev.getContent<T>() : undefined);
+const tryGetContent = <T extends {}>(ev?: MatrixEvent): T | undefined => ev?.getContent<T>();
 
 // Hook to simplify listening to Matrix account data
 export const useAccountData = <T extends {}>(cli: MatrixClient, eventType: string): T => {
-    const [value, setValue] = useState<T>(() => tryGetContent<T>(cli.getAccountData(eventType)));
+    const [value, setValue] = useState<T | undefined>(() => tryGetContent<T>(cli.getAccountData(eventType)));
 
     const handler = useCallback(
         (event) => {
@@ -41,7 +41,7 @@ export const useAccountData = <T extends {}>(cli: MatrixClient, eventType: strin
 
 // Hook to simplify listening to Matrix room account data
 export const useRoomAccountData = <T extends {}>(room: Room, eventType: string): T => {
-    const [value, setValue] = useState<T>(() => tryGetContent<T>(room.getAccountData(eventType)));
+    const [value, setValue] = useState<T | undefined>(() => tryGetContent<T>(room.getAccountData(eventType)));
 
     const handler = useCallback(
         (event) => {

src/hooks/useAsyncMemo.ts

@@ -18,8 +18,8 @@ import { useState, useEffect, DependencyList } from "react";
 
 type Fn<T> = () => Promise<T>;
 
-export const useAsyncMemo = <T>(fn: Fn<T>, deps: DependencyList, initialValue?: T): T => {
-    const [value, setValue] = useState<T>(initialValue);
+export const useAsyncMemo = <T>(fn: Fn<T>, deps: DependencyList, initialValue?: T): T | undefined => {
+    const [value, setValue] = useState<T | undefined>(initialValue);
     useEffect(() => {
         let discard = false;
         fn().then((v) => {

src/hooks/useAudioDeviceSelection.ts

@@ -28,7 +28,7 @@ interface State {
 export const useAudioDeviceSelection = (
     onDeviceChanged?: (device: MediaDeviceInfo) => void,
 ): {
-    currentDevice: MediaDeviceInfo;
+    currentDevice: MediaDeviceInfo | null;
     currentDeviceLabel: string;
     devices: MediaDeviceInfo[];
     setDevice(device: MediaDeviceInfo): void;

src/hooks/useEventEmitter.ts

@@ -22,7 +22,7 @@ import type { EventEmitter } from "events";
 type Handler = (...args: any[]) => void;
 
 export function useTypedEventEmitter<Events extends string, Arguments extends ListenerMap<Events>>(
-    emitter: TypedEventEmitter<Events, Arguments>,
+    emitter: TypedEventEmitter<Events, Arguments> | undefined,
     eventName: Events,
     handler: Handler,
 ): void {

src/hooks/useHover.ts

@@ -17,7 +17,7 @@ limitations under the License.
 import { useState } from "react";
 
 export default function useHover(
-    ignoreHover?: (ev: React.MouseEvent) => boolean,
+    ignoreHover: (ev: React.MouseEvent) => boolean,
 ): [boolean, { onMouseOver: () => void; onMouseLeave: () => void; onMouseMove: (ev: React.MouseEvent) => void }] {
     const [hovered, setHoverState] = useState(false);
 

src/hooks/useProfileInfo.ts

@@ -39,7 +39,7 @@ export const useProfileInfo = (): {
 
     const [loading, setLoading] = useState(false);
 
-    const [updateQuery, updateResult] = useLatestResult<string, IProfileInfo | null>(setProfile);
+    const [updateQuery, updateResult] = useLatestResult<string | undefined, IProfileInfo | null>(setProfile);
 
     const search = useCallback(
         async ({ query: term }: IProfileInfoOpts): Promise<boolean> => {

src/hooks/useRoomState.ts

@@ -28,8 +28,8 @@ const defaultMapper: Mapper<RoomState> = (roomState: RoomState) => roomState;
 export const useRoomState = <T extends any = RoomState>(
     room?: Room,
     mapper: Mapper<T> = defaultMapper as Mapper<T>,
-): T => {
-    const [value, setValue] = useState<T>(room ? mapper(room.currentState) : undefined);
+): T | undefined => {
+    const [value, setValue] = useState<T | undefined>(room ? mapper(room.currentState) : undefined);
 
     const update = useCallback(() => {
         if (!room) return;