Prevent voice message from displaying spurious errors (#30736)

* fix: avoid to render `AudioPlayerViewModel` when `MAudioBody` is inherited

* fix: avoid `Playback.prepare` to fail when called twice

* fix: add `decoding` to playback type

* refactor: fix circular deps

* refactor: extract `MockedPlayback` from `AudioPlayerViewModel`

* test: add `MAudioBody` basic test

* test: add tests for `MVoiceMessageBody`

* fix: lint

src/audio/Playback.ts

@@ -20,6 +20,7 @@ import { DEFAULT_WAVEFORM, PLAYBACK_WAVEFORM_SAMPLES } from "./consts";
 import { PlaybackEncoder } from "../PlaybackEncoder";
 
 export enum PlaybackState {
+    Preparing = "preparing", // preparing to decode
     Decoding = "decoding",
     Stopped = "stopped", // no progress on timeline
     Paused = "paused", // some progress on timeline
@@ -146,6 +147,8 @@ export class Playback extends EventEmitter implements IDestroyable, PlaybackInte
             return;
         }
 
+        this.state = PlaybackState.Preparing;
+
         // The point where we use an audio element is fairly arbitrary, though we don't want
         // it to be too low. As of writing, voice messages want to show a waveform but audio
         // messages do not. Using an audio element means we can't show a waveform preview, so

src/components/views/audio_messages/RecordingPlayback.tsx

@@ -74,7 +74,11 @@ export default class RecordingPlayback extends AudioPlayerBase<IProps> {
         }
 
         return (
-            <div className="mx_MediaBody mx_VoiceMessagePrimaryContainer" onKeyDown={this.onKeyDown}>
+            <div
+                className="mx_MediaBody mx_VoiceMessagePrimaryContainer"
+                onKeyDown={this.onKeyDown}
+                data-testid="recording-playback"
+            >
                 <PlayPauseButton
                     playback={this.props.playback}
                     playbackPhase={this.state.playbackPhase}

src/components/views/messages/MAudioBody.tsx

@@ -6,7 +6,7 @@ SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Com
 Please see LICENSE files in the repository root for full details.
 */
 
-import React from "react";
+import React, { type JSX, useEffect, useMemo } from "react";
 import { logger } from "matrix-js-sdk/src/logger";
 import { type IContent } from "matrix-js-sdk/src/matrix";
 import { type MediaEventContent } from "matrix-js-sdk/src/types";
@@ -17,8 +17,6 @@ import { _t } from "../../../languageHandler";
 import MFileBody from "./MFileBody";
 import { type IBodyProps } from "./IBodyProps";
 import { PlaybackManager } from "../../../audio/PlaybackManager";
-import { isVoiceMessage } from "../../../utils/EventUtils";
-import { PlaybackQueue } from "../../../audio/PlaybackQueue";
 import RoomContext, { TimelineRenderingType } from "../../../contexts/RoomContext";
 import MediaProcessingError from "./shared/MediaProcessingError";
 import { AudioPlayerViewModel } from "../../../viewmodels/audio/AudioPlayerViewModel";
@@ -27,7 +25,6 @@ import { AudioPlayerView } from "../../../shared-components/audio/AudioPlayerVie
 interface IState {
     error?: boolean;
     playback?: Playback;
-    audioPlayerVm?: AudioPlayerViewModel;
 }
 
 export default class MAudioBody extends React.PureComponent<IBodyProps, IState> {
@@ -38,7 +35,6 @@ export default class MAudioBody extends React.PureComponent<IBodyProps, IState>
 
     public async componentDidMount(): Promise<void> {
         let buffer: ArrayBuffer;
-
         try {
             try {
                 const blob = await this.props.mediaEventHelper!.sourceBlob.value;
@@ -63,18 +59,16 @@ export default class MAudioBody extends React.PureComponent<IBodyProps, IState>
         // We should have a buffer to work with now: let's set it up
         const playback = PlaybackManager.instance.createPlaybackInstance(buffer, waveform);
         playback.clockInfo.populatePlaceholdersFrom(this.props.mxEvent);
-        this.setState({ playback, audioPlayerVm: new AudioPlayerViewModel({ playback, mediaName: content.body }) });
+        this.setState({ playback });
 
-        if (isVoiceMessage(this.props.mxEvent)) {
+        this.onMount(playback);
-            PlaybackQueue.forRoom(this.props.mxEvent.getRoomId()!).unsortedEnqueue(this.props.mxEvent, playback);
+        // Note: the components later on will handle preparing the Playback class for us
-        }
-
-        // Note: the components later on will handle preparing the Playback class for us.
     }
 
+    protected onMount(playback: Playback): void {}
+
     public componentWillUnmount(): void {
         this.state.playback?.destroy();
-        this.state.audioPlayerVm?.dispose();
     }
 
     protected get showFileBody(): boolean {
@@ -116,9 +110,35 @@ export default class MAudioBody extends React.PureComponent<IBodyProps, IState>
         // At this point we should have a playable state
         return (
             <span className="mx_MAudioBody">
-                {this.state.audioPlayerVm && <AudioPlayerView vm={this.state.audioPlayerVm} />}
+                <AudioPlayer playback={this.state.playback} mediaName={this.props.mxEvent.getContent().body} />
                 {this.showFileBody && <MFileBody {...this.props} showGenericPlaceholder={false} />}
             </span>
         );
     }
 }
+
+interface AudioPlayerProps {
+    /**
+     * The playback instance to control audio playback.
+     */
+    playback: Playback;
+    /**
+     * The name of the media being played
+     */
+    mediaName: string;
+}
+
+/**
+ * AudioPlayer component that initializes the AudioPlayerViewModel and renders the AudioPlayerView.
+ */
+function AudioPlayer({ playback, mediaName }: AudioPlayerProps): JSX.Element {
+    const vm = useMemo(() => new AudioPlayerViewModel({ playback, mediaName }), [playback, mediaName]);
+
+    useEffect(() => {
+        return () => {
+            vm.dispose();
+        };
+    }, [vm]);
+
+    return <AudioPlayerView vm={vm} />;
+}

src/components/views/messages/MVoiceMessageBody.tsx

@@ -14,8 +14,17 @@ import RecordingPlayback from "../audio_messages/RecordingPlayback";
 import MAudioBody from "./MAudioBody";
 import MFileBody from "./MFileBody";
 import MediaProcessingError from "./shared/MediaProcessingError";
+import { isVoiceMessage } from "../../../utils/EventUtils";
+import { PlaybackQueue } from "../../../audio/PlaybackQueue";
+import { type Playback } from "../../../audio/Playback";
 
 export default class MVoiceMessageBody extends MAudioBody {
+    protected onMount(playback: Playback): void {
+        if (isVoiceMessage(this.props.mxEvent)) {
+            PlaybackQueue.forRoom(this.props.mxEvent.getRoomId()!).unsortedEnqueue(this.props.mxEvent, playback);
+        }
+    }
+
     // A voice message is an audio file but rendered in a special way.
     public render(): React.ReactNode {
         if (this.state.error) {

src/shared-components/audio/playback.ts

@@ -7,9 +7,10 @@
 
 /**
  * Represents the possible states of playback.
+ * - "preparing": The audio is being prepared for playback (e.g., loading or buffering).
  * - "decoding": The audio is being decoded and is not ready for playback.
  * - "stopped": The playback has been stopped, with no progress on the timeline.
  * - "paused": The playback is paused, with some progress on the timeline.
  * - "playing": The playback is actively progressing through the timeline.
  */
-export type PlaybackState = "decoding" | "stopped" | "paused" | "playing";
+export type PlaybackState = "decoding" | "stopped" | "paused" | "playing" | "preparing";

test/unit-tests/audio/MockedPlayback.ts

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+import EventEmitter from "events";
+import { SimpleObservable } from "matrix-widget-api";
+
+import { PlaybackState } from "../../../src/audio/Playback";
+
+/**
+ * A mocked playback implementation for testing purposes.
+ * It simulates a playback with a fixed size and allows state changes.
+ */
+export class MockedPlayback extends EventEmitter {
+    public sizeBytes = 8000;
+    private waveformObservable = new SimpleObservable<number[]>();
+    public liveData = new SimpleObservable<number[]>();
+
+    public constructor(
+        public currentState: PlaybackState,
+        public durationSeconds: number,
+        public timeSeconds: number,
+    ) {
+        super();
+    }
+
+    public setState(state: PlaybackState): void {
+        this.currentState = state;
+        this.emit("update", state);
+    }
+
+    public get isPlaying(): boolean {
+        return this.currentState === PlaybackState.Playing;
+    }
+
+    public get clockInfo() {
+        return {
+            liveData: this.liveData,
+            populatePlaceholdersFrom: () => undefined,
+        };
+    }
+
+    public get waveform(): number[] {
+        return [];
+    }
+
+    public get waveformData(): SimpleObservable<number[]> {
+        return this.waveformObservable;
+    }
+
+    public prepare = jest.fn().mockResolvedValue(undefined);
+    public skipTo = jest.fn();
+    public toggle = jest.fn();
+    public destroy = jest.fn().mockResolvedValue(undefined);
+}

test/unit-tests/components/views/messages/MAudioBody-test.tsx

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+import React from "react";
+import { EventType, MatrixEvent } from "matrix-js-sdk/src/matrix";
+import { render, screen, act } from "jest-matrix-react";
+
+import { MockedPlayback } from "../../../audio/MockedPlayback";
+import { type Playback, PlaybackState } from "../../../../../src/audio/Playback";
+import MAudioBody from "../../../../../src/components/views/messages/MAudioBody";
+import { PlaybackManager } from "../../../../../src/audio/PlaybackManager";
+import { type MediaEventHelper } from "../../../../../src/utils/MediaEventHelper";
+
+describe("<MAudioBody />", () => {
+    let event: MatrixEvent;
+    beforeEach(() => {
+        const playback = new MockedPlayback(PlaybackState.Decoding, 50, 10) as unknown as Playback;
+        jest.spyOn(PlaybackManager.instance, "createPlaybackInstance").mockReturnValue(playback);
+
+        event = new MatrixEvent({
+            room_id: "!room:server",
+            sender: "@alice.example.org",
+            type: EventType.RoomMessage,
+            content: {
+                body: "audio name ",
+                msgtype: "m.audio",
+                url: "mxc://server/audio",
+            },
+        });
+    });
+
+    it("should render", async () => {
+        const mediaEventHelper = {
+            sourceBlob: {
+                value: {
+                    arrayBuffer: () => new ArrayBuffer(8),
+                },
+            },
+        } as unknown as MediaEventHelper;
+
+        await act(() => render(<MAudioBody mxEvent={event} mediaEventHelper={mediaEventHelper} />));
+        expect(await screen.findByRole("region", { name: "Audio player" })).toBeInTheDocument();
+    });
+});

test/unit-tests/components/views/messages/MVoiceMessageBody-test.tsx

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+import { EventType, MatrixEvent, Room } from "matrix-js-sdk/src/matrix";
+import { act, render, screen } from "jest-matrix-react";
+import React from "react";
+
+import { MockedPlayback } from "../../../audio/MockedPlayback";
+import { type Playback, PlaybackState } from "../../../../../src/audio/Playback";
+import { PlaybackManager } from "../../../../../src/audio/PlaybackManager";
+import type { MediaEventHelper } from "../../../../../src/utils/MediaEventHelper";
+import MVoiceMessageBody from "../../../../../src/components/views/messages/MVoiceMessageBody";
+import { PlaybackQueue } from "../../../../../src/audio/PlaybackQueue";
+import { createTestClient } from "../../../../test-utils";
+
+describe("<MVvoiceMessageBody />", () => {
+    let event: MatrixEvent;
+    beforeEach(() => {
+        const playback = new MockedPlayback(PlaybackState.Decoding, 50, 10) as unknown as Playback;
+        jest.spyOn(PlaybackManager.instance, "createPlaybackInstance").mockReturnValue(playback);
+
+        const matrixClient = createTestClient();
+        const room = new Room("!TESTROOM", matrixClient, "@alice:example.org");
+        const playbackQueue = new PlaybackQueue(room);
+
+        jest.spyOn(PlaybackQueue, "forRoom").mockReturnValue(playbackQueue);
+        jest.spyOn(playbackQueue, "unsortedEnqueue").mockReturnValue(undefined);
+
+        event = new MatrixEvent({
+            room_id: "!room:server",
+            sender: "@alice.example.org",
+            type: EventType.RoomMessage,
+            content: {
+                "body": "audio name ",
+                "msgtype": "m.audio",
+                "url": "mxc://server/audio",
+                "org.matrix.msc3946.voice": true,
+            },
+        });
+    });
+
+    it("should render", async () => {
+        const mediaEventHelper = {
+            sourceBlob: {
+                value: {
+                    arrayBuffer: () => new ArrayBuffer(8),
+                },
+            },
+        } as unknown as MediaEventHelper;
+
+        await act(() => render(<MVoiceMessageBody mxEvent={event} mediaEventHelper={mediaEventHelper} />));
+        expect(await screen.findByTestId("recording-playback")).toBeInTheDocument();
+    });
+});

test/viewmodels/audio/AudioPlayerViewModel-test.tsx

@@ -5,18 +5,17 @@
  * Please see LICENSE files in the repository root for full details.
  */
 
-import EventEmitter from "events";
-import { SimpleObservable } from "matrix-widget-api";
 import { type ChangeEvent, type KeyboardEvent as ReactKeyboardEvent } from "react";
 import { waitFor } from "@testing-library/dom";
 
 import { type Playback, PlaybackState } from "../../../src/audio/Playback";
 import { AudioPlayerViewModel } from "../../../src/viewmodels/audio/AudioPlayerViewModel";
+import { MockedPlayback } from "../../unit-tests/audio/MockedPlayback";
 
 describe("AudioPlayerViewModel", () => {
-    let playback: MockedPlayback & Playback;
+    let playback: Playback;
     beforeEach(() => {
-        playback = new MockedPlayback(PlaybackState.Decoding, 50, 10) as unknown as MockedPlayback & Playback;
+        playback = new MockedPlayback(PlaybackState.Decoding, 50, 10) as unknown as Playback;
     });
 
     it("should return the snapshot", () => {
@@ -66,38 +65,3 @@ describe("AudioPlayerViewModel", () => {
         expect(playback.skipTo).toHaveBeenCalledWith(10 + 5); // 5 seconds forward
     });
 });
-
-/**
- * A mocked playback implementation for testing purposes.
- * It simulates a playback with a fixed size and allows state changes.
- */
-class MockedPlayback extends EventEmitter {
-    public sizeBytes = 8000;
-
-    public constructor(
-        public currentState: PlaybackState,
-        public durationSeconds: number,
-        public timeSeconds: number,
-    ) {
-        super();
-    }
-
-    public setState(state: PlaybackState): void {
-        this.currentState = state;
-        this.emit("update", state);
-    }
-
-    public get isPlaying(): boolean {
-        return this.currentState === PlaybackState.Playing;
-    }
-
-    public get clockInfo() {
-        return {
-            liveData: new SimpleObservable(),
-        };
-    }
-
-    public prepare = jest.fn().mockResolvedValue(undefined);
-    public skipTo = jest.fn();
-    public toggle = jest.fn();
-}