fix: allow textTracks redefinition on repeated HLS source-set

src/plugins/adaptive-streaming/videojs-contrib-hlsjs.js

@@ -105,6 +105,7 @@ function Html5HlsJS(source, tech) {
   // if native text tracks are not supported on this browser.
   if (!tech.featuresNativeTextTracks) {
     Object.defineProperty(el, 'textTracks', {
+      configurable: true,
       get: function() {
         try {
           return typeof tech.textTracks === 'function' ? tech.textTracks() : tech.textTracks;

test/unit/videojs-contrib-hlsjs-texttracks.test.js

@@ -0,0 +1,73 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+// Minimal hls.js mock: only what videojs-contrib-hlsjs.js touches at module
+// load time and inside Html5HlsJS(). Real hls.js needs MediaSource/browser
+// APIs jsdom doesn't provide, and none of that is relevant to this bug -
+// the bug is pure Object.defineProperty semantics on the <video> element.
+vi.mock('hls.js', () => {
+  function Hls() {
+    this.on = vi.fn();
+    this.attachMedia = vi.fn();
+    this.loadSource = vi.fn();
+    this.destroy = vi.fn();
+    this.recoverMediaError = vi.fn();
+    this.swapAudioCodec = vi.fn();
+  }
+  Hls.isSupported = () => true;
+  Hls.Events = {};
+  Hls.ErrorTypes = { NETWORK_ERROR: 'networkError', MEDIA_ERROR: 'mediaError' };
+  return { default: Hls };
+});
+
+/**
+ * The module under test has no exports - it registers HlsSourceHandler with
+ * window.videojs as a side effect of being imported. We capture that
+ * reference through a fake videojs so we can call the *real* handleSource
+ * (and therefore the real Html5HlsJS) directly, the same code path video.js
+ * calls in the browser.
+ */
+async function loadRealHlsSourceHandler() {
+  let captured = null;
+  window.videojs = {
+    getTech: (name) => (name === 'Html5' ? { registerSourceHandler: (handler) => { captured = handler; } } : undefined),
+  };
+
+  vi.resetModules();
+  await import('../../src/plugins/adaptive-streaming/videojs-contrib-hlsjs.js');
+
+  delete window.videojs;
+  return captured;
+}
+
+function makeTech(el) {
+  return {
+    options_: {},
+    el: () => el,
+    featuresNativeTextTracks: false, // Chrome/most non-Safari browsers - the branch that defines `textTracks`
+    textTracks: () => [],
+    addTextTrack: vi.fn(),
+    trigger: vi.fn(),
+  };
+}
+
+describe('videojs-contrib-hlsjs.js - textTracks redefinition on a second HLS source', () => {
+  let HlsSourceHandler;
+
+  beforeEach(async () => {
+    HlsSourceHandler = await loadRealHlsSourceHandler();
+  });
+
+  it('reproduces the reported bug: setting a second HLS source on the same <video> element throws', () => {
+    // Only relevant if the fix under test has been reverted - see README note
+    // in the PR / VIDEO-XXXXX for how to flip this locally.
+    const el = document.createElement('video');
+    const source = { src: 'https://example.com/video.m3u8' };
+
+    // First source (e.g. hls/h265) - defines `textTracks` on the element.
+    expect(() => HlsSourceHandler.handleSource(source, makeTech(el))).not.toThrow();
+
+    // Fallback source on the SAME element (e.g. hls/h265 -> hls/h264 after a 400),
+    // mirrors what videojs does when swapping sources without recreating the tech.
+    expect(() => HlsSourceHandler.handleSource(source, makeTech(el))).not.toThrow();
+  });
+});