Strip comments from everything except metadata

osu.Game/Beatmaps/Formats/LegacyBeatmapDecoder.cs

@@ -62,32 +62,34 @@ protected override void ParseStreamInto(StreamReader stream, Beatmap beatmap)
 
         protected override void ParseLine(Beatmap beatmap, Section section, string line)
         {
+            var stripped_line = StripComments(line);
+
             switch (section)
             {
                 case Section.General:
-                    handleGeneral(line);
+                    handleGeneral(stripped_line);
                     return;
                 case Section.Editor:
-                    handleEditor(line);
+                    handleEditor(stripped_line);
                     return;
                 case Section.Metadata:
                     handleMetadata(line);
                     return;
                 case Section.Difficulty:
-                    handleDifficulty(line);
+                    handleDifficulty(stripped_line);
                     return;
                 case Section.Events:
-                    handleEvent(line);
+                    handleEvent(stripped_line);
                     return;
                 case Section.TimingPoints:
-                    handleTimingPoint(line);
+                    handleTimingPoint(stripped_line);
                     return;
                 case Section.HitObjects:
-                    handleHitObject(line);
+                    handleHitObject(stripped_line);
                     return;
             }
 
-            base.ParseLine(beatmap, section, line);
+            base.ParseLine(beatmap, section, stripped_line);
         }
 
         private void handleGeneral(string line)

osu.Game/Beatmaps/Formats/LegacyDecoder.cs

@@ -58,6 +58,8 @@ protected override void ParseStreamInto(StreamReader stream, T output)
 
         protected virtual void ParseLine(T output, Section section, string line)
         {
+            line = StripComments(line);
+
             switch (section)
             {
                 case Section.Colours:
@@ -65,6 +67,13 @@ protected virtual void ParseLine(T output, Section section, string line)
                     return;
             }
         }
+        internal string StripComments(string line)
+        {
+            var index = line.IndexOf("//");
+            if (index > 0)
+                return line.Substring(0, index);
+            return line;
+        }
 
         private bool hasComboColours;
 
@@ -74,12 +83,10 @@ private void handleColours(T output, string line)
 
             bool isCombo = pair.Key.StartsWith(@"Combo");
 
-            line = Regex.Replace(pair.Value, "[^0-9,]", "");
-
-            string[] split = line.Split(',');
+            string[] split = pair.Value.Split(',');
 
             if (split.Length != 3)
-                throw new InvalidOperationException($@"Color specified in incorrect format (should be R,G,B): {line}");
+                throw new InvalidOperationException($@"Color specified in incorrect format (should be R,G,B): {pair.Value}");
 
             if (!byte.TryParse(split[0], out var r) || !byte.TryParse(split[1], out var g) || !byte.TryParse(split[2], out var b))
                 throw new InvalidOperationException(@"Color must be specified with 8-bit integer components");

osu.Game/Beatmaps/Formats/LegacyStoryboardDecoder.cs

@@ -42,6 +42,8 @@ protected override void ParseStreamInto(StreamReader stream, Storyboard storyboa
 
         protected override void ParseLine(Storyboard storyboard, Section section, string line)
         {
+            line = StripComments(line);
+
             switch (section)
             {
                 case Section.Events:

osu.Game/Skinning/LegacySkinDecoder.cs

@@ -14,6 +14,8 @@ public LegacySkinDecoder()
 
         protected override void ParseLine(SkinConfiguration skin, Section section, string line)
         {
+            line = StripComments(line);
+
             switch (section)
             {
                 case Section.General: