MainWindow.gd

@@ -186,7 +186,6 @@ func _ready() -> void:
 	
 	get_suggestion_list()
 	fetch_song_list_at_start()
-	fetch_song()
 	search_view.get_list_of_soundtracks()
 	new_character_select.load_characters()
 	
@@ -240,14 +239,12 @@ func show_answer_pressed() -> void:
 	Playlist.song_is_answered()
 	update_song_list()
 
+# Loads the songs already in the server playlist, then starts preloading new ones.
+# Preloading waits for the list, because loading the list clears the playlist.
 func fetch_song_list_at_start() -> void:
 	print("fetch_song_list_at_start")
 	var fetch_song_list_at_start_done: Callable = func fetch_songs_at_start_done(data) -> void:
 		Playlist.clear_song_list()
-		if data == null:
-			Playlist.update_last_played_song()
-			update_song_list()
-			return
 		if typeof(data) == TYPE_ARRAY:
 			for d: Dictionary in data:
 				var new_song_object: SongObject = SongObject.new()
@@ -257,11 +254,14 @@ func fetch_song_list_at_start() -> void:
 				new_song_object.is_answered = true
 				new_song_object.has_played = true
 				Playlist.add_to_playlist(new_song_object)
-		else:
+		elif data != null:
 			print("Unexpected data")
 		Playlist.update_last_played_song()
 		update_song_list()
-	MusicServerClient.fetch_song_list(fetch_song_list_at_start_done)
+		if !Playlist.is_song_downloading:
+			fetch_song()
+	MusicServerClient.fetch_song_list(fetch_song_list_at_start_done,
+			_retry_later.bind(fetch_song_list_at_start))
 
 func play_next_song() -> void:
 	print("play_next_song ", Playlist.latest_played_song)
@@ -360,7 +360,6 @@ func reset_playlist() -> void:
 	var playlist_reset_done: Callable = func playlist_reset_done() -> void:
 		Playlist.reset_playlist()
 		fetch_song_list_at_start()
-		fetch_song()
 		
 	MusicServerClient.reset_playlist(playlist_reset_done)
 

tests/fakes/fake_http_transport.gd

@@ -13,6 +13,7 @@ var requested_methods: Array[int] = []
 
 var _responses: Dictionary = {}
 var _successes_left: Dictionary = {}
+var _held_paths: Dictionary = {}
 var _previous_transport: HttpTransport
 
 
@@ -49,6 +50,20 @@ func fail_after(path: String, successes: int) -> void:
     _successes_left[path] = successes
 
 
+## Holds back responses to [param path] until [method release] is called, like a slow
+## server.
+func hold(path: String) -> void:
+    _held_paths[path] = []
+
+
+## Delivers the responses held back for [param path] and stops holding it.
+func release(path: String) -> void:
+    var waiting: Array = _held_paths.get(path, [])
+    _held_paths.erase(path)
+    for pending: Callable in waiting:
+        pending.call()
+
+
 ## Returns how many times [param path] has been requested.
 func count(path: String) -> int:
     return requested_paths.count(path)
@@ -58,6 +73,13 @@ func request(url: String, method: int, on_complete: Callable) -> void:
     var path: String = url.trim_prefix(Settings.default_path)
     requested_paths.append(path)
     requested_methods.append(method)
+    if _held_paths.has(path):
+        _held_paths[path].append(_answer.bind(path, on_complete))
+        return
+    _answer(path, on_complete)
+
+
+func _answer(path: String, on_complete: Callable) -> void:
     if _successes_left.has(path):
         if _successes_left[path] == 0:
             on_complete.call(503, PackedByteArray())

tests/fakes/main_window_test_suite.gd

@@ -36,12 +36,19 @@ func before_test() -> void:
     _server.respond_bytes("/music/reset", PackedByteArray())
     _server.respond_bytes("/music/played?song=0", PackedByteArray())
 
+    _before_window_starts()
     _runner = scene_runner("res://MainWindow.tscn")
     _window = _runner.scene()
     # The debug build lowers the winning score on startup; keep it out of reach
     Settings.winning_score = 20
 
 
+## Override to change the fake server before the window starts and sends its first
+## requests.
+func _before_window_starts() -> void:
+    pass
+
+
 func after_test() -> void:
     # Let nodes queued for deletion by the window be freed before orphans are counted
     await await_idle_frame()

tests/integration/test_main_window_startup.gd

@@ -0,0 +1,41 @@
+extends MainWindowTestSuite
+## Startup with a slow /music/list response.
+
+
+func _before_window_starts() -> void:
+    _server.respond_json("/music/list", [
+        {"SongNo": 0, "Soundtrack": "Chrono Trigger", "Song": "Corridors of Time"},
+    ])
+    _next_song_is({"SongNo": 1, "Soundtrack": "Final Fantasy VI", "Song": "Dancing Mad"})
+    _server.hold("/music/list")
+
+
+func test_preloaded_song_survives_a_slow_song_list() -> void:
+    _server.release("/music/list")
+
+    # The song already on the server, then the preloaded one
+    assert_int(Playlist.song_object_array.size()).is_equal(2)
+    assert_str(Playlist.song_object_array[1].song_title).is_equal("Dancing Mad")
+    assert_int(Playlist.get_preloaded_songs()).is_equal(1)
+
+
+func test_next_plays_the_preloaded_song_after_a_slow_song_list() -> void:
+    _server.release("/music/list")
+
+    await _play_first_song()
+
+    assert_int(Playlist.currently_playing_song).is_equal(1)
+
+
+func test_failed_song_list_is_retried_before_preloading() -> void:
+    _window.song_fetch_retry_seconds = 0.05
+    _server.respond_json("/music/list", [], 503)
+    _server.release("/music/list")
+
+    assert_int(_server.count("/music/rand")).is_equal(0)
+
+    _server.respond_json("/music/list", [])
+    await await_millis(200)
+
+    assert_int(_server.count("/music/rand")).is_equal(1)
+    assert_int(Playlist.get_preloaded_songs()).is_equal(1)

tests/integration/test_main_window_startup.gd.uid

@@ -0,0 +1 @@
+uid://sfwrqidmuj04