From 7fa0ac6ed720b32bcb3c52b05f3cf8352c69927a Mon Sep 17 00:00:00 2001
From: smoogipoo <smoogipoo@smgi.me>
Date: Tue, 8 Jun 2021 17:03:46 +0900
Subject: [PATCH] Fix possible nullref when exiting song select too fast

---
 .../Visual/Navigation/TestSceneScreenNavigation.cs        | 8 ++++++++
 osu.Game/Screens/Select/SongSelect.cs                     | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/osu.Game.Tests/Visual/Navigation/TestSceneScreenNavigation.cs b/osu.Game.Tests/Visual/Navigation/TestSceneScreenNavigation.cs
index 0308d74aa4..3694d3afce 100644
--- a/osu.Game.Tests/Visual/Navigation/TestSceneScreenNavigation.cs
+++ b/osu.Game.Tests/Visual/Navigation/TestSceneScreenNavigation.cs
@@ -152,6 +152,14 @@ namespace osu.Game.Tests.Visual.Navigation
             AddUntilStep("wait for track", () => !Game.MusicController.CurrentTrack.IsDummyDevice && Game.MusicController.IsPlaying);
         }
 
+        [Test]
+        public void TestPushSongSelectAndPressBackButtonImmediately()
+        {
+            AddStep("push song select", () => Game.ScreenStack.Push(new TestPlaySongSelect()));
+            AddStep("press back button", () => Game.ChildrenOfType<BackButton>().First().Action());
+            AddWaitStep("wait two frame", 2);
+        }
+
         [Test]
         public void TestExitSongSelectWithClick()
         {
diff --git a/osu.Game/Screens/Select/SongSelect.cs b/osu.Game/Screens/Select/SongSelect.cs
index 270addc8e6..c697c64c3f 100644
--- a/osu.Game/Screens/Select/SongSelect.cs
+++ b/osu.Game/Screens/Select/SongSelect.cs
@@ -665,7 +665,7 @@ namespace osu.Game.Screens.Select
 
         public override bool OnBackButton()
         {
-            if (ModSelect.State.Value == Visibility.Visible)
+            if (ModSelect?.State.Value == Visibility.Visible)
             {
                 ModSelect.Hide();
                 return true;