Conform more of the codebase to strictNullChecks

src/LegacyCallHandler.tsx

@@ -652,9 +652,9 @@ export default class LegacyCallHandler extends EventEmitter {
     }
 
     private onCallStateChanged = (newState: CallState, oldState: CallState | null, call: MatrixCall): void => {
-        if (!this.matchesCallForThisRoom(call)) return;
-
         const mappedRoomId = this.roomIdForCall(call);
+        if (!mappedRoomId || !this.matchesCallForThisRoom(call)) return;
+
         this.setCallState(call, newState);
         dis.dispatch({
             action: "call_state",

src/audio/PlaybackClock.ts

@@ -60,7 +60,7 @@ export class PlaybackClock implements IDestroyable {
     private stopped = true;
     private lastCheck = 0;
     private observable = new SimpleObservable<number[]>();
-    private timerId: number;
+    private timerId?: number;
     private clipDuration = 0;
     private placeholderDuration = 0;
 

src/audio/VoiceMessageRecording.ts

@@ -33,9 +33,9 @@ export interface IUpload {
  * This class can be used to record a single voice message.
  */
 export class VoiceMessageRecording implements IDestroyable {
-    private lastUpload: IUpload;
+    private lastUpload?: IUpload;
     private buffer = new Uint8Array(0); // use this.audioBuffer to access
-    private playback: Playback;
+    private playback?: Playback;
 
     public constructor(private matrixClient: MatrixClient, private voiceRecording: VoiceRecording) {
         this.voiceRecording.onDataAvailable = this.onDataAvailable;

src/audio/VoiceRecording.ts

@@ -243,7 +243,7 @@ export class VoiceRecording extends EventEmitter implements IDestroyable {
             return;
         }
 
-        const secondsLeft = TARGET_MAX_LENGTH - this.recorderSeconds;
+        const secondsLeft = TARGET_MAX_LENGTH - this.recorderSeconds!;
         if (secondsLeft < 0) {
             // go over to make sure we definitely capture that last frame
             // noinspection JSIgnoredPromiseFromCall - we aren't concerned with it overlapping
@@ -259,7 +259,8 @@ export class VoiceRecording extends EventEmitter implements IDestroyable {
     /**
      * {@link https://github.com/chris-rudmin/opus-recorder#instance-fields ref for recorderSeconds}
      */
-    public get recorderSeconds(): number {
+    public get recorderSeconds(): number | undefined {
+        if (!this.recorder) return undefined;
         return this.recorder.encodedSamplePosition / 48000;
     }
 

src/components/structures/IndicatorScrollbar.tsx

@@ -44,7 +44,7 @@ export default class IndicatorScrollbar<T extends keyof JSX.IntrinsicElements> e
     IState
 > {
     private autoHideScrollbar = createRef<AutoHideScrollbar<any>>();
-    private scrollElement: HTMLDivElement;
+    private scrollElement?: HTMLDivElement;
     private likelyTrackpadUser: boolean | null = null;
     private checkAgainForTrackpad = 0; // ts in milliseconds to recheck this._likelyTrackpadUser
 
@@ -85,6 +85,7 @@ export default class IndicatorScrollbar<T extends keyof JSX.IntrinsicElements> e
     }
 
     private checkOverflow = (): void => {
+        if (!this.scrollElement) return;
         const hasTopOverflow = this.scrollElement.scrollTop > 0;
         const hasBottomOverflow =
             this.scrollElement.scrollHeight > this.scrollElement.scrollTop + this.scrollElement.clientHeight;

src/components/structures/LegacyCallEventGrouper.ts

@@ -73,7 +73,7 @@ export function buildLegacyCallEventGroupers(
 export default class LegacyCallEventGrouper extends EventEmitter {
     private events: Set<MatrixEvent> = new Set<MatrixEvent>();
     private call: MatrixCall | null = null;
-    public state: CallState | CustomCallState;
+    public state?: CallState | CustomCallState;
 
     public constructor() {
         super();

src/components/structures/LoggedInView.tsx

@@ -96,10 +96,10 @@ interface IProps {
     autoJoin?: boolean;
     threepidInvite?: IThreepidInvite;
     roomOobData?: IOOBData;
-    currentRoomId: string;
+    currentRoomId: string | null;
     collapseLhs: boolean;
     config: ConfigOptions;
-    currentUserId: string;
+    currentUserId: string | null;
     justRegistered?: boolean;
     roomJustCreatedOpts?: IOpts;
     forceTimeline?: boolean; // see props on MatrixChat
@@ -131,10 +131,10 @@ class LoggedInView extends React.Component<IProps, IState> {
     protected readonly _roomView: React.RefObject<RoomViewType>;
     protected readonly _resizeContainer: React.RefObject<HTMLDivElement>;
     protected readonly resizeHandler: React.RefObject<HTMLDivElement>;
-    protected layoutWatcherRef: string;
-    protected compactLayoutWatcherRef: string;
-    protected backgroundImageWatcherRef: string;
-    protected resizer: Resizer;
+    protected layoutWatcherRef?: string;
+    protected compactLayoutWatcherRef?: string;
+    protected backgroundImageWatcherRef?: string;
+    protected resizer?: Resizer;
 
     public constructor(props: IProps) {
         super(props);
@@ -200,10 +200,10 @@ class LoggedInView extends React.Component<IProps, IState> {
         this._matrixClient.removeListener(ClientEvent.Sync, this.onSync);
         this._matrixClient.removeListener(RoomStateEvent.Events, this.onRoomStateEvents);
         OwnProfileStore.instance.off(UPDATE_EVENT, this.refreshBackgroundImage);
-        SettingsStore.unwatchSetting(this.layoutWatcherRef);
-        SettingsStore.unwatchSetting(this.compactLayoutWatcherRef);
-        SettingsStore.unwatchSetting(this.backgroundImageWatcherRef);
-        this.resizer.detach();
+        if (this.layoutWatcherRef) SettingsStore.unwatchSetting(this.layoutWatcherRef);
+        if (this.compactLayoutWatcherRef) SettingsStore.unwatchSetting(this.compactLayoutWatcherRef);
+        if (this.backgroundImageWatcherRef) SettingsStore.unwatchSetting(this.backgroundImageWatcherRef);
+        this.resizer?.detach();
     }
 
     private onCallState = (): void => {
@@ -274,7 +274,7 @@ class LoggedInView extends React.Component<IProps, IState> {
         if (isNaN(lhsSize)) {
             lhsSize = 350;
         }
-        this.resizer.forHandleWithId("lp-resizer")?.resize(lhsSize);
+        this.resizer?.forHandleWithId("lp-resizer")?.resize(lhsSize);
     }
 
     private onAccountData = (event: MatrixEvent): void => {
@@ -645,7 +645,11 @@ class LoggedInView extends React.Component<IProps, IState> {
                 break;
 
             case PageTypes.UserView:
-                pageElement = <UserView userId={this.props.currentUserId} resizeNotifier={this.props.resizeNotifier} />;
+                if (!!this.props.currentUserId) {
+                    pageElement = (
+                        <UserView userId={this.props.currentUserId} resizeNotifier={this.props.resizeNotifier} />
+                    );
+                }
                 break;
         }
 

src/components/structures/MatrixChat.tsx

@@ -231,7 +231,7 @@ export default class MatrixChat extends React.PureComponent<IProps, IState> {
     private focusComposer: boolean;
     private subTitleStatus: string;
     private prevWindowWidth: number;
-    private voiceBroadcastResumer: VoiceBroadcastResumer;
+    private voiceBroadcastResumer?: VoiceBroadcastResumer;
 
     private readonly loggedInView: React.RefObject<LoggedInViewType>;
     private readonly dispatcherRef: string;
@@ -441,7 +441,7 @@ export default class MatrixChat extends React.PureComponent<IProps, IState> {
         window.removeEventListener("resize", this.onWindowResized);
 
         this.stores.accountPasswordStore.clearPassword();
-        if (this.voiceBroadcastResumer) this.voiceBroadcastResumer.destroy();
+        this.voiceBroadcastResumer?.destroy();
     }
 
     private onWindowResized = (): void => {
@@ -1935,7 +1935,7 @@ export default class MatrixChat extends React.PureComponent<IProps, IState> {
     private setPageSubtitle(subtitle = ""): void {
         if (this.state.currentRoomId) {
             const client = MatrixClientPeg.get();
-            const room = client && client.getRoom(this.state.currentRoomId);
+            const room = client?.getRoom(this.state.currentRoomId);
             if (room) {
                 subtitle = `${this.subTitleStatus} | ${room.name} ${subtitle}`;
             }

src/components/structures/ScrollPanel.tsx

@@ -179,7 +179,7 @@ export default class ScrollPanel extends React.Component<IProps> {
     };
     private readonly itemlist = createRef<HTMLOListElement>();
     private unmounted = false;
-    private scrollTimeout: Timer;
+    private scrollTimeout?: Timer;
     // Are we currently trying to backfill?
     private isFilling: boolean;
     // Is the current fill request caused by a props update?
@@ -189,8 +189,8 @@ export default class ScrollPanel extends React.Component<IProps> {
     // Is that next fill request scheduled because of a props update?
     private pendingFillDueToPropsUpdate: boolean;
     private scrollState: IScrollState;
-    private preventShrinkingState: IPreventShrinkingState | null;
-    private unfillDebouncer: number | null;
+    private preventShrinkingState: IPreventShrinkingState | null = null;
+    private unfillDebouncer: number | null = null;
     private bottomGrowth: number;
     private minListHeight: number;
     private heightUpdateInProgress: boolean;
@@ -234,7 +234,7 @@ export default class ScrollPanel extends React.Component<IProps> {
         // skip scroll events caused by resizing
         if (this.props.resizeNotifier && this.props.resizeNotifier.isResizing) return;
         debuglog("onScroll called past resize gate; scroll node top:", this.getScrollNode().scrollTop);
-        this.scrollTimeout.restart();
+        this.scrollTimeout?.restart();
         this.saveScrollState();
         this.updatePreventShrinking();
         this.props.onScroll?.(ev);
@@ -725,7 +725,7 @@ export default class ScrollPanel extends React.Component<IProps> {
     // need a better name that also indicates this will change scrollTop? Rebalance height? Reveal content?
     private async updateHeight(): Promise<void> {
         // wait until user has stopped scrolling
-        if (this.scrollTimeout.isRunning()) {
+        if (this.scrollTimeout?.isRunning()) {
             debuglog("updateHeight waiting for scrolling to end ... ");
             await this.scrollTimeout.finished();
             debuglog("updateHeight actually running now");

src/components/structures/UserMenu.tsx

@@ -88,9 +88,9 @@ export default class UserMenu extends React.Component<IProps, IState> {
     public static contextType = SDKContext;
     public context!: React.ContextType<typeof SDKContext>;
 
-    private dispatcherRef: string;
-    private themeWatcherRef: string;
-    private readonly dndWatcherRef: string;
+    private dispatcherRef?: string;
+    private themeWatcherRef?: string;
+    private readonly dndWatcherRef?: string;
     private buttonRef: React.RefObject<HTMLButtonElement> = createRef();
 
     public constructor(props: IProps, context: React.ContextType<typeof SDKContext>) {

src/components/structures/auth/Registration.tsx

@@ -125,7 +125,7 @@ interface IState {
 export default class Registration extends React.Component<IProps, IState> {
     private readonly loginLogic: Login;
     // `replaceClient` tracks latest serverConfig to spot when it changes under the async method which fetches flows
-    private latestServerConfig: ValidatedServerConfig;
+    private latestServerConfig?: ValidatedServerConfig;
 
     public constructor(props: IProps) {
         super(props);

src/components/views/auth/InteractiveAuthEntryComponents.tsx

@@ -556,8 +556,8 @@ export class MsisdnAuthEntry extends React.Component<IMsisdnAuthEntryProps, IMsi
     public static LOGIN_TYPE = AuthType.Msisdn;
 
     private submitUrl?: string;
-    private sid: string;
-    private msisdn: string;
+    private sid?: string;
+    private msisdn?: string;
 
     public constructor(props: IMsisdnAuthEntryProps) {
         super(props);
@@ -615,8 +615,8 @@ export class MsisdnAuthEntry extends React.Component<IMsisdnAuthEntryProps, IMsi
         });
 
         try {
-            let result;
-            if (this.submitUrl) {
+            let result: { success: boolean };
+            if (this.submitUrl && this.sid) {
                 result = await this.props.matrixClient.submitMsisdnTokenOtherUrl(
                     this.submitUrl,
                     this.sid,

src/components/views/dialogs/ReportEventDialog.tsx

@@ -19,7 +19,7 @@ import React, { ChangeEvent } from "react";
 import { MatrixEvent } from "matrix-js-sdk/src/models/event";
 import { logger } from "matrix-js-sdk/src/logger";
 
-import { _t } from "../../../languageHandler";
+import { _t, UserFriendlyError } from "../../../languageHandler";
 import { ensureDMExists } from "../../../createRoom";
 import { MatrixClientPeg } from "../../../MatrixClientPeg";
 import SdkConfig from "../../../SdkConfig";
@@ -245,6 +245,10 @@ export default class ReportEventDialog extends React.Component<IProps, IState> {
                 // Report to moderators through to the dedicated bot,
                 // as configured in the room's state events.
                 const dmRoomId = await ensureDMExists(client, this.moderation.moderationBotUserId);
+                if (!dmRoomId) {
+                    throw new UserFriendlyError("Unable to create room with moderation bot");
+                }
+
                 await client.sendEvent(dmRoomId, ABUSE_EVENT_TYPE, {
                     event_id: ev.getId(),
                     room_id: ev.getRoomId(),

src/components/views/dialogs/RoomSettingsDialog.tsx

@@ -62,7 +62,7 @@ interface IState {
 }
 
 class RoomSettingsDialog extends React.Component<IProps, IState> {
-    private dispatcherRef: string;
+    private dispatcherRef?: string;
 
     public constructor(props: IProps) {
         super(props);

src/components/views/dialogs/RoomUpgradeDialog.tsx

@@ -35,7 +35,7 @@ interface IState {
 }
 
 export default class RoomUpgradeDialog extends React.Component<IProps, IState> {
-    private targetVersion: string;
+    private targetVersion?: string;
 
     public state = {
         busy: true,
@@ -53,7 +53,7 @@ export default class RoomUpgradeDialog extends React.Component<IProps, IState> {
 
     private onUpgradeClick = (): void => {
         this.setState({ busy: true });
-        upgradeRoom(this.props.room, this.targetVersion, false, false)
+        upgradeRoom(this.props.room, this.targetVersion!, false, false)
             .then(() => {
                 this.props.onFinished(true);
             })
@@ -69,7 +69,7 @@ export default class RoomUpgradeDialog extends React.Component<IProps, IState> {
     };
 
     public render(): React.ReactNode {
-        let buttons;
+        let buttons: JSX.Element;
         if (this.state.busy) {
             buttons = <Spinner />;
         } else {

src/components/views/dialogs/ServerPickerDialog.tsx

@@ -44,7 +44,7 @@ interface IState {
 export default class ServerPickerDialog extends React.PureComponent<IProps, IState> {
     private readonly defaultServer: ValidatedServerConfig;
     private readonly fieldRef = createRef<Field>();
-    private validatedConf: ValidatedServerConfig;
+    private validatedConf?: ValidatedServerConfig;
 
     public constructor(props: IProps) {
         super(props);
@@ -85,7 +85,7 @@ export default class ServerPickerDialog extends React.PureComponent<IProps, ISta
     // find their homeserver without demanding they use "https://matrix.org"
     private validate = withValidation<this, { error?: string }>({
         deriveData: async ({ value }): Promise<{ error?: string }> => {
-            let hsUrl = value.trim(); // trim to account for random whitespace
+            let hsUrl = (value ?? "").trim(); // trim to account for random whitespace
 
             // if the URL has no protocol, try validate it as a serverName via well-known
             if (!hsUrl.includes("://")) {

src/components/views/dialogs/SetEmailDialog.tsx

@@ -45,7 +45,7 @@ interface IState {
  * On success, `onFinished(true)` is called.
  */
 export default class SetEmailDialog extends React.Component<IProps, IState> {
-    private addThreepid: AddThreepid;
+    private addThreepid?: AddThreepid;
 
     public constructor(props: IProps) {
         super(props);
@@ -109,7 +109,7 @@ export default class SetEmailDialog extends React.Component<IProps, IState> {
     };
 
     private verifyEmailAddress(): void {
-        this.addThreepid.checkEmailLinkClicked().then(
+        this.addThreepid?.checkEmailLinkClicked().then(
             () => {
                 this.props.onFinished(true);
             },

src/components/views/elements/AppTile.tsx

@@ -121,11 +121,11 @@ export default class AppTile extends React.Component<IProps, IState> {
     };
 
     private contextMenuButton = createRef<any>();
-    private iframe: HTMLIFrameElement; // ref to the iframe (callback style)
-    private allowedWidgetsWatchRef: string;
+    private iframe?: HTMLIFrameElement; // ref to the iframe (callback style)
+    private allowedWidgetsWatchRef?: string;
     private persistKey: string;
     private sgWidget: StopGapWidget | null;
-    private dispatcherRef: string;
+    private dispatcherRef?: string;
     private unmounted: boolean;
 
     public constructor(props: IProps) {
@@ -305,7 +305,7 @@ export default class AppTile extends React.Component<IProps, IState> {
             this.context.off(RoomEvent.MyMembership, this.onMyMembership);
         }
 
-        SettingsStore.unwatchSetting(this.allowedWidgetsWatchRef);
+        if (this.allowedWidgetsWatchRef) SettingsStore.unwatchSetting(this.allowedWidgetsWatchRef);
         OwnProfileStore.instance.removeListener(UPDATE_EVENT, this.onUserReady);
     }
 
@@ -344,7 +344,7 @@ export default class AppTile extends React.Component<IProps, IState> {
 
     private startMessaging(): void {
         try {
-            this.sgWidget?.startMessaging(this.iframe);
+            this.sgWidget?.startMessaging(this.iframe!);
         } catch (e) {
             logger.error("Failed to start widget", e);
         }

src/components/views/elements/DesktopCapturerSourcePicker.tsx

@@ -88,7 +88,7 @@ export interface PickerIProps {
 type TabId = "screen" | "window";
 
 export default class DesktopCapturerSourcePicker extends React.Component<PickerIProps, PickerIState> {
-    public interval: number;
+    public interval?: number;
 
     public constructor(props: PickerIProps) {
         super(props);