From ac0e5c36b4e9e7123469766e11c0db9d4033ad7c Mon Sep 17 00:00:00 2001
From: willdharris <will.harris@paramount.com>
Date: Mon, 10 Apr 2023 10:11:23 -0400
Subject: [PATCH] Add test to verify a single text stream loads

---
 CONTRIBUTORS                       |  1 +
 test/player_integration.js         | 39 ++++++++++++++++++
 test/test/assets/text-clip-alt.vtt | 63 ++++++++++++++++++++++++++++++
 3 files changed, 103 insertions(+)
 create mode 100644 test/test/assets/text-clip-alt.vtt

diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 2e42b38a4d..83df12b5bb 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -131,6 +131,7 @@ Vincent Valot <valot.vince@gmail.com>
 Vinod Balakrishnan <vinod.balakrishnan@v-nova.com>
 Wayne Morgan <wayne.morgan.dev@gmail.com>
 Wen Ren <renwen0615@gmail.com>
+Will Harris <will3harris@gmail.com>
 Yohann Connell <robinconnell@google.com>
 Raymond Cheng <raycheng100@gmail.com>
 Janroel Koppen <j.koppen@bluebillywig.com>
diff --git a/test/player_integration.js b/test/player_integration.js
index 41a04205c1..e0a3832bd1 100644
--- a/test/player_integration.js
+++ b/test/player_integration.js
@@ -319,6 +319,45 @@ describe('Player', () => {
       player.setTextTrackVisibility(true);
       expect(getTracksActive()).toEqual([false, true]);
     });
+
+    // https://github.com/shaka-project/shaka-player/issues/4821
+    it('loads a single text stream', async () => {
+      player.configure({preferredTextLanguage: 'en'});
+      await player.load('test:sintel_no_text_compiled');
+
+      // Add preferred language text track.
+      const locationUri = new goog.Uri(location.href);
+      const partialUri = new goog.Uri('/base/test/test/assets/text-clip.vtt');
+      const absoluteUri = locationUri.resolve(partialUri);
+      await player.addTextTrackAsync(
+          absoluteUri.toString(), 'en', 'subtitles', 'text/vtt');
+
+      // Add alternate language text track.
+      // Two text tracks with same timings but different text
+      // are necessary for test.
+      const partialUri2 =
+      new goog.Uri('/base/test/test/assets/text-clip-alt.vtt');
+      const absoluteUri2 = locationUri.resolve(partialUri2);
+      await player.addTextTrackAsync(
+          absoluteUri2.toString(), 'fr', 'subtitles', 'text/vtt');
+
+      const textTracks = player.getTextTracks();
+      expect(textTracks.length).toBe(2);
+      expect(textTracks[0].language).toBe('en');
+      expect(textTracks[1].language).toBe('fr');
+
+      // Enable text visibilty and immediately change language.
+      // Only one set of cues should be active.
+      // Cues should be of the selected language track.
+      player.setTextTrackVisibility(true);
+      player.selectTextLanguage('fr');
+      video.currentTime = 5;
+      video.play();
+      await waiter.waitForMovementOrFailOnTimeout(video, 10);
+
+      expect(video.textTracks[0].activeCues.length).toBe(1);
+      expect(player.getTextTracks()[1].active).toBe(true);
+    });
   });  // describe('setTextTrackVisibility')
 
   describe('autoShowText', () => {
diff --git a/test/test/assets/text-clip-alt.vtt b/test/test/assets/text-clip-alt.vtt
new file mode 100644
index 0000000000..92b922a603
--- /dev/null
+++ b/test/test/assets/text-clip-alt.vtt
@@ -0,0 +1,63 @@
+WEBVTT
+
+00:04.000 --> 00:07.300
+Journal de bord du capitaine.
+Date stellaire 41636.9.
+
+00:07.500 --> 00:11.800
+Comme nous le craignions, l'épave
+du cargo Odin de la Fédération,
+
+00:12.100 --> 00:16.400
+percuté par un astéroïde,
+ne révèle aucun signe de vie.
+
+00:16.700 --> 00:19.000
+Mais trois nacelles
+de sauvetage manquaient,
+
+00:19.300 --> 00:21.900
+laissant supposer
+qu'il y aurait des survivants.
+
+00:22.700 --> 00:27.700
+- Mise sur orbite Angel One, paré.
+- Quel genre d'endroit, Data ?
+
+00:28.200 --> 00:31.600
+Planète de Classe-M.
+Faune et flore à base de carbone.
+
+00:31.900 --> 00:34.300
+Population éparse
+et forme de vie intelligente.
+
+00:34.600 --> 00:38.400
+Développement technique équivalent
+au milieu du 20ème siècle terrien.
+
+00:38.800 --> 00:41.000
+C'est presque un retour aux sources.
+
+00:41.300 --> 00:43.600
+Si jamais des survivants
+ont pu aller si loin,
+
+00:43.800 --> 00:49.000
+c'était la planète la plus proche.
+La distance qui nous a pris 2 jours
+
+00:49.500 --> 00:52.400
+aurait pris 5 mois aux nacelles
+de sauvetage du Odin.
+
+00:52.600 --> 00:54.700
+Cinq mois, six jours, onze heures,
+deux min...
+
+00:54.900 --> 00:58.400
+- Merci, Data.
+- ..et 57 secondes.
+
+00:58.600 --> 01:01.300
+Signal audio provenant d'Angel One.