Enable @typescript-eslint/explicit-function-return-type in /src (#9788)

* Enable `@typescript-eslint/explicit-member-accessibility` on /src

* Prettier

* Enable `@typescript-eslint/explicit-function-return-type` in /src

* Fix types

* tsc strict fixes

* Delint

* Fix test

* Fix bad merge

src/components/views/avatars/BaseAvatar.tsx

@@ -99,7 +99,7 @@ const useImageUrl = ({ url, urls }): [string, () => void] => {
     return [imageUrl, onError];
 };
 
-const BaseAvatar = (props: IProps) => {
+const BaseAvatar: React.FC<IProps> = (props) => {
     const {
         name,
         idName,

src/components/views/avatars/DecoratedRoomAvatar.tsx

@@ -62,7 +62,7 @@ enum Icon {
     PresenceBusy = "BUSY",
 }
 
-function tooltipText(variant: Icon) {
+function tooltipText(variant: Icon): string {
     switch (variant) {
         case Icon.Globe:
             return _t("This room is public");
@@ -91,7 +91,7 @@ export default class DecoratedRoomAvatar extends React.PureComponent<IProps, ISt
         };
     }
 
-    public componentWillUnmount() {
+    public componentWillUnmount(): void {
         this.isUnmounted = true;
         if (this.isWatchingTimeline) this.props.room.off(RoomEvent.Timeline, this.onRoomTimeline);
         this.dmUser = null; // clear listeners, if any
@@ -120,7 +120,7 @@ export default class DecoratedRoomAvatar extends React.PureComponent<IProps, ISt
         }
     }
 
-    private onRoomTimeline = (ev: MatrixEvent, room: Room | null) => {
+    private onRoomTimeline = (ev: MatrixEvent, room: Room | null): void => {
         if (this.isUnmounted) return;
         if (this.props.room.roomId !== room?.roomId) return;
 
@@ -132,7 +132,7 @@ export default class DecoratedRoomAvatar extends React.PureComponent<IProps, ISt
         }
     };
 
-    private onPresenceUpdate = () => {
+    private onPresenceUpdate = (): void => {
         if (this.isUnmounted) return;
 
         const newIcon = this.getPresenceIcon();

src/components/views/avatars/MemberAvatar.tsx

@@ -54,7 +54,7 @@ export default function MemberAvatar({
     hideTitle,
     member: propsMember,
     ...props
-}: IProps) {
+}: IProps): JSX.Element {
     const card = useContext(CardContext);
 
     const member = useRoomMemberProfile({

src/components/views/avatars/RoomAvatar.tsx

@@ -63,11 +63,11 @@ export default class RoomAvatar extends React.Component<IProps, IState> {
         };
     }
 
-    public componentDidMount() {
+    public componentDidMount(): void {
         MatrixClientPeg.get().on(RoomStateEvent.Events, this.onRoomStateEvents);
     }
 
-    public componentWillUnmount() {
+    public componentWillUnmount(): void {
         MatrixClientPeg.get()?.removeListener(RoomStateEvent.Events, this.onRoomStateEvents);
     }
 
@@ -77,7 +77,7 @@ export default class RoomAvatar extends React.Component<IProps, IState> {
         };
     }
 
-    private onRoomStateEvents = (ev: MatrixEvent) => {
+    private onRoomStateEvents = (ev: MatrixEvent): void => {
         if (ev.getRoomId() !== this.props.room?.roomId || ev.getType() !== EventType.RoomAvatar) return;
 
         this.setState({
@@ -108,7 +108,7 @@ export default class RoomAvatar extends React.Component<IProps, IState> {
         return Avatar.avatarUrlForRoom(props.room, props.width, props.height, props.resizeMethod);
     }
 
-    private onRoomAvatarClick = () => {
+    private onRoomAvatarClick = (): void => {
         const avatarUrl = Avatar.avatarUrlForRoom(this.props.room, null, null, null);
         const params = {
             src: avatarUrl,
@@ -135,7 +135,7 @@ export default class RoomAvatar extends React.Component<IProps, IState> {
         return this.props.room?.roomId || this.props.oobData?.roomId;
     }
 
-    public render() {
+    public render(): JSX.Element {
         const { room, oobData, viewAvatarOnClick, onClick, className, ...otherProps } = this.props;
         const roomName = room?.name ?? oobData.name;