From 224de9cc1ea9d911b1718f200ae5b3c4b8b10ec5 Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Sat, 5 Aug 2017 11:59:58 +0900
Subject: [PATCH] Implement NoFail mod

---
 osu.Game/Rulesets/Mods/Mod.cs               | 5 +++++
 osu.Game/Rulesets/Mods/ModNoFail.cs         | 5 +++++
 osu.Game/Rulesets/Scoring/ScoreProcessor.cs | 7 ++++---
 osu.Game/Screens/Play/Player.cs             | 6 +++++-
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/osu.Game/Rulesets/Mods/Mod.cs b/osu.Game/Rulesets/Mods/Mod.cs
index c00847b7d8..69daedb7a7 100644
--- a/osu.Game/Rulesets/Mods/Mod.cs
+++ b/osu.Game/Rulesets/Mods/Mod.cs
@@ -45,5 +45,10 @@ namespace osu.Game.Rulesets.Mods
         /// The mods this mod cannot be enabled with.
         /// </summary>
         public virtual Type[] IncompatibleMods => new Type[] { };
+
+        /// <summary>
+        /// Whether we should allow fails at the 
+        /// </summary>
+        public virtual bool AllowFail => true;
     }
 }
diff --git a/osu.Game/Rulesets/Mods/ModNoFail.cs b/osu.Game/Rulesets/Mods/ModNoFail.cs
index 613e1e1d4d..d41c4e3956 100644
--- a/osu.Game/Rulesets/Mods/ModNoFail.cs
+++ b/osu.Game/Rulesets/Mods/ModNoFail.cs
@@ -15,5 +15,10 @@ namespace osu.Game.Rulesets.Mods
         public override double ScoreMultiplier => 0.5;
         public override bool Ranked => true;
         public override Type[] IncompatibleMods => new[] { typeof(ModRelax), typeof(ModSuddenDeath), typeof(ModAutoplay) };
+
+        /// <summary>
+        /// We never fail, 'yo.
+        /// </summary>
+        public override bool AllowFail => false;
     }
 }
\ No newline at end of file
diff --git a/osu.Game/Rulesets/Scoring/ScoreProcessor.cs b/osu.Game/Rulesets/Scoring/ScoreProcessor.cs
index 79fb34a523..cd9089c859 100644
--- a/osu.Game/Rulesets/Scoring/ScoreProcessor.cs
+++ b/osu.Game/Rulesets/Scoring/ScoreProcessor.cs
@@ -16,8 +16,9 @@ namespace osu.Game.Rulesets.Scoring
     {
         /// <summary>
         /// Invoked when the ScoreProcessor is in a failed state.
+        /// Return true if the fail was permitted.
         /// </summary>
-        public event Action Failed;
+        public event Func<bool> Failed;
 
         /// <summary>
         /// Invoked when a new judgement has occurred. This occurs after the judgement has been processed by the <see cref="ScoreProcessor"/>.
@@ -106,8 +107,8 @@ namespace osu.Game.Rulesets.Scoring
             if (alreadyFailed || !HasFailed)
                 return;
 
-            alreadyFailed = true;
-            Failed?.Invoke();
+            if (Failed?.Invoke() != false)
+                alreadyFailed = true;
         }
 
         /// <summary>
diff --git a/osu.Game/Screens/Play/Player.cs b/osu.Game/Screens/Play/Player.cs
index 39128eb85e..345ad60d47 100644
--- a/osu.Game/Screens/Play/Player.cs
+++ b/osu.Game/Screens/Play/Player.cs
@@ -238,13 +238,17 @@ namespace osu.Game.Screens.Play
             }
         }
 
-        private void onFail()
+        private bool onFail()
         {
+            if (Beatmap.Value.Mods.Value.Any(m => !m.AllowFail))
+                return false;
+
             decoupledClock.Stop();
 
             HasFailed = true;
             failOverlay.Retries = RestartCount;
             failOverlay.Show();
+            return true;
         }
 
         protected override void OnEntering(Screen last)