Implement ClosedCaption unit tests and fix closed captions api.

lib/src/reverse_engineering/responses/closed_caption_track_response.dart

@@ -9,7 +9,7 @@ class ClosedCaptionTrackResponse {
   ClosedCaptionTrackResponse(this._root);
 
   Iterable<ClosedCaption> get closedCaptions =>
-      _root.findElements('p').map((e) => ClosedCaption._(e));
+      _root.findAllElements('p').map((e) => ClosedCaption._(e));
 
   ClosedCaptionTrackResponse.parse(String raw) : _root = xml.parse(raw);
 
@@ -37,7 +37,7 @@ class ClosedCaption {
 
   ClosedCaption._(this._root);
 
-  String get text => _root.toXmlString();
+  String get text => _root.text;
 
   Duration get offset =>
       Duration(milliseconds: int.parse(_root.getAttribute('t') ?? 0));
@@ -48,7 +48,7 @@ class ClosedCaption {
   Duration get end => offset + duration;
 
   Iterable<ClosedCaptionPart> getParts() =>
-      _root.findElements('s').map((e) => ClosedCaptionPart._(e));
+      _root.findAllElements('s').map((e) => ClosedCaptionPart._(e));
 }
 
 class ClosedCaptionPart {
@@ -56,8 +56,8 @@ class ClosedCaptionPart {
 
   ClosedCaptionPart._(this._root);
 
-  String get text => _root.toXmlString();
+  String get text => _root.text;
 
   Duration get offset =>
-      Duration(milliseconds: int.parse(_root.getAttribute('t') ?? 0));
+      Duration(milliseconds: int.parse(_root.getAttribute('t') ?? '0'));
 }

lib/src/reverse_engineering/responses/player_response.dart

@@ -85,7 +85,8 @@ class PlayerResponse {
           .get('captions')
           ?.get('playerCaptionsTracklistRenderer')
           ?.getValue('captionTracks')
-          ?.map((e) => ClosedCaptionTrack(e)) ??
+          ?.map((e) => ClosedCaptionTrack(e))
+          ?.cast<ClosedCaptionTrack>() ??
       const [];
 
   String getVideoPlayabilityError() =>

lib/src/videos/closed_captions/closed_caption.dart

@@ -14,6 +14,9 @@ class ClosedCaption {
   /// Duration this caption is displayed.
   final Duration duration;
 
+  /// Time at which this caption ends being displayed.
+  Duration get end => offset + duration;
+
   /// Caption parts (usually individual words).
   /// May be empty because not all captions contain parts.
   final UnmodifiableListView<ClosedCaptionPart> parts;

lib/src/videos/closed_captions/closed_caption_client.dart

@@ -28,7 +28,8 @@ class ClosedCaptionClient {
 
     var tracks = playerResponse.closedCaptionTrack.map((track) =>
         ClosedCaptionTrackInfo(Uri.parse(track.url),
-            Language(track.languageCode, track.languageName)));
+            Language(track.languageCode, track.languageName),
+            isAutoGenerated: track.autoGenerated));
     return ClosedCaptionManifest(tracks);
   }
 

lib/src/videos/closed_captions/closed_caption_track.dart

@@ -10,4 +10,9 @@ class ClosedCaptionTrack {
   /// Initializes an instance of [ClosedCaptionTrack].
   ClosedCaptionTrack(Iterable<ClosedCaption> captions)
       : captions = UnmodifiableListView(captions);
+
+  /// Gets the caption displayed at the specified point in time.
+  /// Returns null if not found.
+  ClosedCaption getByTime(Duration time) => captions
+      .firstWhere((e) => time >= e.offset && time <= e.end, orElse: () => null);
 }

test/closed_caption_test.dart

@@ -1 +1,42 @@
-//TODO: Implement this
+import 'package:test/test.dart';
+import 'package:youtube_explode_dart/youtube_explode_dart.dart';
+
+void main() {
+  group('Search', () {
+    YoutubeExplode yt;
+    setUp(() {
+      yt = YoutubeExplode();
+    });
+
+    tearDown(() {
+      yt.close();
+    });
+
+    test('GetClosedCaptionTracksOfAnyVideo', () async {
+      var manifest = await yt.videos.closedCaptions.getManifest('_QdPW8JrYzQ');
+      expect(manifest.tracks, isNotEmpty);
+    });
+    test('GetClosedCaptionTrackOfAnyVideoSpecific', () async {
+      var manifest = await yt.videos.closedCaptions.getManifest('_QdPW8JrYzQ');
+      var trackInfo = manifest.tracks.first;
+      var track = await yt.videos.closedCaptions.get(trackInfo);
+
+      expect(track, isNotEmpty);
+    });
+    test('GetClosedCaptionTrackAtSpecificTime', () async {
+      var manifest = await yt.videos.closedCaptions
+          .getManifest('https://www.youtube.com/watch?v=YltHGKX80Y8');
+      var trackInfo = manifest.getByLanguage('en');
+      var track = await yt.videos.closedCaptions.get(trackInfo);
+      var caption =
+          track.getByTime(const Duration(hours: 0, minutes: 10, seconds: 41));
+      var captionPart =
+          caption.getPartByTime(const Duration(milliseconds: 650));
+
+      expect(caption, isNotNull);
+      expect(captionPart, isNotNull);
+      expect(caption.text, 'know I worked really hard on not doing');
+      expect(captionPart.text, ' hard');
+    });
+  });
+}