Add tests

osu.Game.Tests/Visual/TestCaseLoaderAnimation.cs

@@ -0,0 +1,101 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using System.Threading;
+using NUnit.Framework;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Shapes;
+using osu.Game.Screens;
+using osu.Game.Screens.Menu;
+using OpenTK.Graphics;
+
+namespace osu.Game.Tests.Visual
+{
+    [TestFixture]
+    public class TestCaseLoaderAnimation : OsuTestCase
+    {
+        private TestLoader loader;
+
+        public TestCaseLoaderAnimation()
+        {
+            bool logoVisible = false;
+
+            AddStep("almost instant display", () => Child = loader = new TestLoader(0.25f));
+            AddUntilStep(() =>
+            {
+                logoVisible = loader.Logo.Alpha > 0;
+                return !loader.IsCurrentScreen;
+            }, "loaded");
+            AddAssert("logo not visible", () => !logoVisible);
+
+            AddStep("short load", () => Child = loader = new TestLoader(0.8f));
+            AddUntilStep(() =>
+            {
+                logoVisible = loader.Logo.Alpha > 0;
+                return !loader.IsCurrentScreen;
+            }, "loaded");
+            AddAssert("logo visible", () => logoVisible);
+            AddUntilStep(() => loader.Logo.Alpha == 0, "logo gone");
+
+            AddStep("longer load", () => Child = loader = new TestLoader(1.4f));
+            AddUntilStep(() =>
+            {
+                logoVisible = loader.Logo.Alpha > 0;
+                return !loader.IsCurrentScreen;
+            }, "loaded");
+            AddAssert("logo visible", () => logoVisible);
+            AddUntilStep(() => loader.Logo.Alpha == 0, "logo gone");
+        }
+
+        private class TestLoader : Loader
+        {
+            private readonly float secondsDelay;
+
+            public OsuLogo Logo;
+
+            public TestLoader(float secondsDelay)
+            {
+                this.secondsDelay = secondsDelay;
+            }
+
+            protected override void LogoArriving(OsuLogo logo, bool resuming)
+            {
+                Logo = logo;
+                base.LogoArriving(logo, resuming);
+            }
+
+            protected override OsuScreen CreateLoadableScreen() => new TestScreen(secondsDelay);
+
+            private class TestScreen : OsuScreen
+            {
+                private readonly float secondsDelay;
+
+                public TestScreen(float secondsDelay)
+                {
+                    this.secondsDelay = secondsDelay;
+
+                    Child = new Box
+                    {
+                        RelativeSizeAxes = Axes.Both,
+                        Colour = Color4.DarkSlateGray,
+                        Alpha = 0,
+                    };
+                }
+
+                [BackgroundDependencyLoader]
+                private void load()
+                {
+                    Thread.Sleep((int)(secondsDelay * 1000));
+                }
+
+                protected override void LogoArriving(OsuLogo logo, bool resuming)
+                {
+                    base.LogoArriving(logo, resuming);
+
+                    Child.FadeInFromZero(200);
+                }
+            }
+        }
+    }
+}

osu.Game/Screens/Loader.cs

@@ -49,12 +49,14 @@ namespace osu.Game.Screens
         private OsuScreen loadScreen;
         private ShaderPrecompiler precompiler;
 
+        protected virtual OsuScreen CreateLoadableScreen() => showDisclaimer ? (OsuScreen)new Disclaimer() : new Intro();
+
         protected override void OnEntering(Screen last)
         {
             base.OnEntering(last);
 
             LoadComponentAsync(precompiler = new ShaderPrecompiler(loadIfReady), Add);
-            LoadComponentAsync(loadScreen = showDisclaimer ? (OsuScreen)new Disclaimer() : new Intro(), s => loadIfReady());
+            LoadComponentAsync(loadScreen = CreateLoadableScreen(), s => loadIfReady());
         }
 
         private void loadIfReady()