From 51d6db1bca65a02f1d66675f2e766125364d7f1e Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Wed, 12 Jan 2022 12:39:40 +0900
Subject: [PATCH] Add equatable support to `IUser` and `RealmUser`

Not sure this will stick, but let's add it for now to make testing
detach support work nicely.
---
 osu.Game/Beatmaps/IBeatmapMetadataInfo.cs |  2 +-
 osu.Game/Models/RealmUser.cs              | 11 ++++++++++-
 osu.Game/Users/IUser.cs                   | 13 ++++++++++++-
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/osu.Game/Beatmaps/IBeatmapMetadataInfo.cs b/osu.Game/Beatmaps/IBeatmapMetadataInfo.cs
index 968ad14928..61adc0ac34 100644
--- a/osu.Game/Beatmaps/IBeatmapMetadataInfo.cs
+++ b/osu.Game/Beatmaps/IBeatmapMetadataInfo.cs
@@ -73,7 +73,7 @@ namespace osu.Game.Beatmaps
                    && TitleUnicode == other.TitleUnicode
                    && Artist == other.Artist
                    && ArtistUnicode == other.ArtistUnicode
-                   && Author == other.Author
+                   && Author.Equals(other.Author)
                    && Source == other.Source
                    && Tags == other.Tags
                    && PreviewTime == other.PreviewTime
diff --git a/osu.Game/Models/RealmUser.cs b/osu.Game/Models/RealmUser.cs
index 154ece502f..ff35528827 100644
--- a/osu.Game/Models/RealmUser.cs
+++ b/osu.Game/Models/RealmUser.cs
@@ -1,17 +1,26 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using osu.Game.Users;
 using Realms;
 
 namespace osu.Game.Models
 {
-    public class RealmUser : EmbeddedObject, IUser
+    public class RealmUser : EmbeddedObject, IUser, IEquatable<RealmUser>
     {
         public int OnlineID { get; set; } = 1;
 
         public string Username { get; set; }
 
         public bool IsBot => false;
+
+        public bool Equals(RealmUser other)
+        {
+            if (ReferenceEquals(null, other)) return false;
+            if (ReferenceEquals(this, other)) return true;
+
+            return OnlineID == other.OnlineID && Username == other.Username;
+        }
     }
 }
diff --git a/osu.Game/Users/IUser.cs b/osu.Game/Users/IUser.cs
index 3995531fd9..d9a352872f 100644
--- a/osu.Game/Users/IUser.cs
+++ b/osu.Game/Users/IUser.cs
@@ -1,14 +1,25 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using osu.Game.Database;
 
+#nullable enable
+
 namespace osu.Game.Users
 {
-    public interface IUser : IHasOnlineID<int>
+    public interface IUser : IHasOnlineID<int>, IEquatable<IUser>
     {
         string Username { get; }
 
         bool IsBot { get; }
+
+        bool IEquatable<IUser>.Equals(IUser? other)
+        {
+            if (other == null)
+                return false;
+
+            return OnlineID == other.OnlineID && Username == other.Username;
+        }
     }
 }