From 22511c36c3b0d306418b55adbb61376796f85187 Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Fri, 25 Sep 2020 17:40:43 +0900
Subject: [PATCH] Ensure toggles are not instantiated more than once for safety

---
 .../Edit/OsuHitObjectComposer.cs              |  2 +-
 osu.Game/Rulesets/Edit/HitObjectComposer.cs   |  8 ++++++--
 .../Components/ComposeBlueprintContainer.cs   | 19 +++++++++++--------
 3 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs b/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs
index 49af80dd63..a4dd463ea5 100644
--- a/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs
+++ b/osu.Game.Rulesets.Osu/Edit/OsuHitObjectComposer.cs
@@ -44,7 +44,7 @@ namespace osu.Game.Rulesets.Osu.Edit
 
         private readonly Bindable<TernaryState> distanceSnapToggle = new Bindable<TernaryState>();
 
-        protected override IEnumerable<TernaryButton> Toggles => base.Toggles.Concat(new[]
+        protected override IEnumerable<TernaryButton> CreateToggles() => base.CreateToggles().Concat(new[]
         {
             new TernaryButton(distanceSnapToggle, "Distance Snap", () => new SpriteIcon { Icon = FontAwesome.Solid.Ruler })
         });
diff --git a/osu.Game/Rulesets/Edit/HitObjectComposer.cs b/osu.Game/Rulesets/Edit/HitObjectComposer.cs
index a592500a87..e692f8d606 100644
--- a/osu.Game/Rulesets/Edit/HitObjectComposer.cs
+++ b/osu.Game/Rulesets/Edit/HitObjectComposer.cs
@@ -133,7 +133,6 @@ namespace osu.Game.Rulesets.Edit
                                 AutoSizeAxes = Axes.Y,
                                 Direction = FillDirection.Vertical,
                                 Spacing = new Vector2(0, 5),
-                                ChildrenEnumerable = Toggles.Select(b => new DrawableTernaryButton(b))
                             },
                         }
                     }
@@ -145,6 +144,9 @@ namespace osu.Game.Rulesets.Edit
                                       .Select(t => new RadioButton(t.Name, () => toolSelected(t), t.CreateIcon))
                                       .ToList();
 
+            Toggles = CreateToggles().ToArray();
+            togglesCollection.AddRange(Toggles.Select(b => new DrawableTernaryButton(b)));
+
             setSelectTool();
 
             EditorBeatmap.SelectedHitObjects.CollectionChanged += selectionChanged;
@@ -176,7 +178,9 @@ namespace osu.Game.Rulesets.Edit
         /// A collection of toggles which will be displayed to the user.
         /// The display name will be decided by <see cref="Bindable{T}.Description"/>.
         /// </summary>
-        protected virtual IEnumerable<TernaryButton> Toggles => BlueprintContainer.Toggles;
+        public TernaryButton[] Toggles { get; private set; }
+
+        protected virtual IEnumerable<TernaryButton> CreateToggles() => BlueprintContainer.Toggles;
 
         /// <summary>
         /// Construct a relevant blueprint container. This will manage hitobject selection/placement input handling and display logic.
diff --git a/osu.Game/Screens/Edit/Compose/Components/ComposeBlueprintContainer.cs b/osu.Game/Screens/Edit/Compose/Components/ComposeBlueprintContainer.cs
index cab277f10b..0f4bab8b33 100644
--- a/osu.Game/Screens/Edit/Compose/Components/ComposeBlueprintContainer.cs
+++ b/osu.Game/Screens/Edit/Compose/Components/ComposeBlueprintContainer.cs
@@ -51,6 +51,8 @@ namespace osu.Game.Screens.Edit.Compose.Components
         [BackgroundDependencyLoader]
         private void load()
         {
+            Toggles = CreateToggles().ToArray();
+
             AddInternal(placementBlueprintContainer);
         }
 
@@ -66,21 +68,22 @@ namespace osu.Game.Screens.Edit.Compose.Components
             // we are responsible for current placement blueprint updated based on state changes.
             NewCombo.ValueChanged += combo =>
             {
-                if (currentPlacement != null)
-                {
-                    if (currentPlacement.HitObject is IHasComboInformation c)
-                        c.NewCombo = combo.NewValue == TernaryState.True;
-                }
+                if (currentPlacement == null) return;
+
+                if (currentPlacement.HitObject is IHasComboInformation c)
+                    c.NewCombo = combo.NewValue == TernaryState.True;
             };
         }
 
         public readonly Bindable<TernaryState> NewCombo = new Bindable<TernaryState> { Description = "New Combo" };
 
-        public virtual IEnumerable<TernaryButton> Toggles => new[]
+        public TernaryButton[] Toggles { get; private set; }
+
+        protected virtual IEnumerable<TernaryButton> CreateToggles()
         {
             //TODO: this should only be enabled (visible?) for rulesets that provide combo-supporting HitObjects.
-            new TernaryButton(NewCombo, "New combo", () => new SpriteIcon { Icon = FontAwesome.Regular.DotCircle })
-        };
+            yield return new TernaryButton(NewCombo, "New combo", () => new SpriteIcon { Icon = FontAwesome.Regular.DotCircle });
+        }
 
         #region Placement