Provide names and pools when creating MiniYaml.

- Rename the filename parameter to name and make it mandatory. Review all callers and ensure a useful string is provided as input, to ensure sufficient context is included for logging and debugging. This can be a filename, url, or any arbitrary text so include whatever context seems reasonable.
- When several MiniYamls are created that have similar content, provide a shared string pool. This allows strings that are common between all the yaml to be shared, reducing long term memory usage. We also change the pool from a dictionary to a set. Originally a Dictionary had to be used so we could call TryGetValue to get a reference to the pooled string. Now that more recent versions of dotnet provide a TryGetValue on HashSet, we can use a set directly without the memory wasted by having to store both keys and values in a dictionary.

OpenRA.Game/ExternalMods.cs

@@ -66,6 +66,7 @@ namespace OpenRA
 			// Several types of support directory types are available, depending on
 			// how the player has installed and launched the game.
 			// Read registration metadata from all of them
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			foreach (var source in GetSupportDirs(ModRegistration.User | ModRegistration.System))
 			{
 				var metadataPath = Path.Combine(source, "ModMetadata");
@@ -76,7 +77,7 @@ namespace OpenRA
 				{
 					try
 					{
-						var yaml = MiniYaml.FromStream(File.OpenRead(path), path).First().Value;
+						var yaml = MiniYaml.FromFile(path, stringPool: stringPool).First().Value;
 						LoadMod(yaml, path);
 					}
 					catch (Exception e)
@@ -205,7 +206,7 @@ namespace OpenRA
 					string modKey = null;
 					try
 					{
-						var yaml = MiniYaml.FromStream(File.OpenRead(path), path).First().Value;
+						var yaml = MiniYaml.FromFile(path).First().Value;
 						var m = FieldLoader.Load<ExternalMod>(yaml);
 						modKey = ExternalMod.MakeKey(m);
 

OpenRA.Game/Exts.cs

@@ -130,6 +130,20 @@ namespace OpenRA
 			return ret;
 		}
 
+		public static T GetOrAdd<T>(this HashSet<T> set, T value)
+		{
+			if (!set.TryGetValue(value, out var ret))
+				set.Add(ret = value);
+			return ret;
+		}
+
+		public static T GetOrAdd<T>(this HashSet<T> set, T value, Func<T, T> createFn)
+		{
+			if (!set.TryGetValue(value, out var ret))
+				set.Add(ret = createFn(value));
+			return ret;
+		}
+
 		public static int IndexOf<T>(this T[] array, T value)
 		{
 			return Array.IndexOf(array, value);

OpenRA.Game/FileFormats/ReplayMetadata.cs

@@ -48,7 +48,7 @@ namespace OpenRA.FileFormats
 
 			// Read game info (max 100K limit as a safeguard against corrupted files)
 			var data = fs.ReadLengthPrefixedString(Encoding.UTF8, 1024 * 100);
-			GameInfo = GameInformation.Deserialize(data);
+			GameInfo = GameInformation.Deserialize(data, path);
 		}
 
 		public void Write(BinaryWriter writer)

OpenRA.Game/GameInformation.cs

@@ -49,13 +49,13 @@ namespace OpenRA
 			playersByRuntime = new Dictionary<OpenRA.Player, Player>();
 		}
 
-		public static GameInformation Deserialize(string data)
+		public static GameInformation Deserialize(string data, string path)
 		{
 			try
 			{
 				var info = new GameInformation();
 
-				var nodes = MiniYaml.FromString(data);
+				var nodes = MiniYaml.FromString(data, path);
 				foreach (var node in nodes)
 				{
 					var keyParts = node.Key.Split('@');

OpenRA.Game/Graphics/ChromeProvider.cs

@@ -77,8 +77,9 @@ namespace OpenRA.Graphics
 			cachedPanelSprites = new Dictionary<string, Sprite[]>();
 			cachedCollectionSheets = new Dictionary<Collection, (Sheet, int)>();
 
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			var chrome = MiniYaml.Merge(modData.Manifest.Chrome
-				.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s)));
+				.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s, stringPool: stringPool)));
 
 			foreach (var c in chrome)
 				if (!c.Key.StartsWith('^'))

OpenRA.Game/Graphics/CursorProvider.cs

@@ -24,8 +24,9 @@ namespace OpenRA.Graphics
 		public CursorProvider(ModData modData)
 		{
 			var fileSystem = modData.DefaultFileSystem;
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			var sequenceYaml = MiniYaml.Merge(modData.Manifest.Cursors.Select(
-				s => MiniYaml.FromStream(fileSystem.Open(s), s)));
+				s => MiniYaml.FromStream(fileSystem.Open(s), s, stringPool: stringPool)));
 
 			var cursorsYaml = new MiniYaml(null, sequenceYaml).NodeWithKey("Cursors").Value;
 

OpenRA.Game/LocalPlayerProfile.cs

@@ -84,10 +84,11 @@ namespace OpenRA
 				{
 					var client = HttpClientFactory.Create();
 
-					var httpResponseMessage = await client.GetAsync(playerDatabase.Profile + Fingerprint);
+					var url = playerDatabase.Profile + Fingerprint;
+					var httpResponseMessage = await client.GetAsync(url);
 					var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-					var yaml = MiniYaml.FromStream(result).First();
+					var yaml = MiniYaml.FromStream(result, url).First();
 					if (yaml.Key == "Player")
 					{
 						innerData = FieldLoader.Load<PlayerProfile>(yaml.Value);

OpenRA.Game/Manifest.cs

@@ -94,7 +94,8 @@ namespace OpenRA
 			Id = modId;
 			Package = package;
 
-			var nodes = MiniYaml.FromStream(package.GetStream("mod.yaml"), "mod.yaml");
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
+			var nodes = MiniYaml.FromStream(package.GetStream("mod.yaml"), $"{package.Name}:mod.yaml", stringPool: stringPool);
 			for (var i = nodes.Count - 1; i >= 0; i--)
 			{
 				if (nodes[i].Key != "Include")
@@ -107,7 +108,7 @@ namespace OpenRA
 					throw new YamlException($"{nodes[i].Location}: File `{filename}` not found.");
 
 				nodes.RemoveAt(i);
-				nodes.InsertRange(i, MiniYaml.FromStream(contents, filename));
+				nodes.InsertRange(i, MiniYaml.FromStream(contents, $"{package.Name}:{filename}", stringPool: stringPool));
 			}
 
 			// Merge inherited overrides

OpenRA.Game/Map/Map.cs

@@ -361,7 +361,7 @@ namespace OpenRA
 			if (!Package.Contains("map.yaml") || !Package.Contains("map.bin"))
 				throw new InvalidDataException($"Not a valid map\n File: {package.Name}");
 
-			var yaml = new MiniYaml(null, MiniYaml.FromStream(Package.GetStream("map.yaml"), package.Name));
+			var yaml = new MiniYaml(null, MiniYaml.FromStream(Package.GetStream("map.yaml"), $"{package.Name}:map.yaml"));
 			foreach (var field in YamlFields)
 				field.Deserialize(this, yaml);
 

OpenRA.Game/Map/MapCache.cs

@@ -38,7 +38,7 @@ namespace OpenRA
 		readonly object syncRoot = new();
 		readonly Queue<MapPreview> generateMinimap = new();
 
-		public Dictionary<string, string> StringPool { get; } = new Dictionary<string, string>();
+		public HashSet<string> StringPool { get; } = new();
 
 		readonly List<MapDirectoryTracker> mapDirectoryTrackers = new();
 
@@ -238,6 +238,7 @@ namespace OpenRA
 			Task.Run(async () =>
 			{
 				var client = HttpClientFactory.Create();
+				var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 
 				// Limit each query to 50 maps at a time to avoid request size limits
 				for (var i = 0; i < queryUids.Count; i += 50)
@@ -249,7 +250,7 @@ namespace OpenRA
 						var httpResponseMessage = await client.GetAsync(url);
 						var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-						var yaml = MiniYaml.FromStream(result);
+						var yaml = MiniYaml.FromStream(result, url, stringPool: stringPool);
 						foreach (var kv in yaml)
 							previews[kv.Key].UpdateRemoteSearch(MapStatus.DownloadAvailable, kv.Value, modData.Manifest.MapCompatibility, mapDetailsReceived);
 

OpenRA.Game/Map/MapPreview.cs

@@ -140,9 +140,10 @@ namespace OpenRA
 							files = files.Append(mapFiles);
 						}
 
+						var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 						var sources =
 							modDataRules.Select(x => x.Where(IsLoadableRuleDefinition).ToList())
-							.Concat(files.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s).Where(IsLoadableRuleDefinition).ToList()));
+							.Concat(files.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s, stringPool: stringPool).Where(IsLoadableRuleDefinition).ToList()));
 						if (RuleDefinitions.Nodes.Length > 0)
 							sources = sources.Append(RuleDefinitions.Nodes.Where(IsLoadableRuleDefinition).ToList());
 
@@ -334,7 +335,7 @@ namespace OpenRA
 				if (yamlStream == null)
 					throw new FileNotFoundException("Required file map.yaml not present in this map");
 
-				yaml = new MiniYaml(null, MiniYaml.FromStream(yamlStream, "map.yaml", stringPool: cache.StringPool)).ToDictionary();
+				yaml = new MiniYaml(null, MiniYaml.FromStream(yamlStream, $"{p.Name}:map.yaml", stringPool: cache.StringPool)).ToDictionary();
 			}
 
 			Package = p;
@@ -475,10 +476,12 @@ namespace OpenRA
 					}
 
 					var playersString = Encoding.UTF8.GetString(Convert.FromBase64String(r.players_block));
-					newData.Players = new MapPlayers(MiniYaml.FromString(playersString));
+					newData.Players = new MapPlayers(MiniYaml.FromString(playersString,
+						$"{yaml.NodeWithKey(nameof(r.players_block)).Location.Name}:{nameof(r.players_block)}"));
 
 					var rulesString = Encoding.UTF8.GetString(Convert.FromBase64String(r.rules));
-					var rulesYaml = new MiniYaml("", MiniYaml.FromString(rulesString)).ToDictionary();
+					var rulesYaml = new MiniYaml("", MiniYaml.FromString(rulesString,
+						$"{yaml.NodeWithKey(nameof(r.rules)).Location.Name}:{nameof(r.rules)}")).ToDictionary();
 					newData.SetCustomRules(modData, this, rulesYaml, null);
 
 					// Map is for a different mod: update its information so it can be displayed

OpenRA.Game/MiniYaml.cs

@@ -61,16 +61,16 @@ namespace OpenRA
 	{
 		public readonly struct SourceLocation
 		{
-			public readonly string Filename;
+			public readonly string Name;
 			public readonly int Line;
 
-			public SourceLocation(string filename, int line)
+			public SourceLocation(string name, int line)
 			{
-				Filename = filename;
+				Name = name;
 				Line = line;
 			}
 
-			public override string ToString() { return $"{Filename}:{Line}"; }
+			public override string ToString() { return $"{Name}:{Line}"; }
 		}
 
 		public readonly SourceLocation Location;
@@ -203,9 +203,13 @@ namespace OpenRA
 			Nodes = ImmutableArray.CreateRange(nodes);
 		}
 
-		static List<MiniYamlNode> FromLines(IEnumerable<ReadOnlyMemory<char>> lines, string filename, bool discardCommentsAndWhitespace, Dictionary<string, string> stringPool)
+		static List<MiniYamlNode> FromLines(IEnumerable<ReadOnlyMemory<char>> lines, string name, bool discardCommentsAndWhitespace, HashSet<string> stringPool)
 		{
-			stringPool ??= new Dictionary<string, string>();
+			// YAML config often contains repeated strings for key, values, comments.
+			// Pool these strings so we only need one copy of each unique string.
+			// This saves on long-term memory usage as parsed values can often live a long time.
+			// A caller can also provide a pool as input, allowing de-duplication across multiple parses.
+			stringPool ??= new HashSet<string>();
 
 			var result = new List<List<MiniYamlNode>>
 			{
@@ -227,7 +231,7 @@ namespace OpenRA
 				ReadOnlySpan<char> key = default;
 				ReadOnlySpan<char> value = default;
 				ReadOnlySpan<char> comment = default;
-				var location = new MiniYamlNode.SourceLocation(filename, lineNo);
+				var location = new MiniYamlNode.SourceLocation(name, lineNo);
 
 				if (line.Length > 0)
 				{
@@ -330,9 +334,9 @@ namespace OpenRA
 					// (i.e. a lone # at the end of a line) can be correctly re-serialized
 					var commentString = comment == default ? null : comment.ToString();
 
-					keyString = keyString == null ? null : stringPool.GetOrAdd(keyString, keyString);
+					keyString = keyString == null ? null : stringPool.GetOrAdd(keyString);
-					valueString = valueString == null ? null : stringPool.GetOrAdd(valueString, valueString);
+					valueString = valueString == null ? null : stringPool.GetOrAdd(valueString);
-					commentString = commentString == null ? null : stringPool.GetOrAdd(commentString, commentString);
+					commentString = commentString == null ? null : stringPool.GetOrAdd(commentString);
 
 					parsedLines.Add((level, keyString, valueString, commentString, location));
 				}
@@ -376,19 +380,19 @@ namespace OpenRA
 			}
 		}
 
-		public static List<MiniYamlNode> FromFile(string path, bool discardCommentsAndWhitespace = true, Dictionary<string, string> stringPool = null)
+		public static List<MiniYamlNode> FromFile(string path, bool discardCommentsAndWhitespace = true, HashSet<string> stringPool = null)
 		{
 			return FromStream(File.OpenRead(path), path, discardCommentsAndWhitespace, stringPool);
 		}
 
-		public static List<MiniYamlNode> FromStream(Stream s, string fileName = "<no filename available>", bool discardCommentsAndWhitespace = true, Dictionary<string, string> stringPool = null)
+		public static List<MiniYamlNode> FromStream(Stream s, string name, bool discardCommentsAndWhitespace = true, HashSet<string> stringPool = null)
 		{
-			return FromLines(s.ReadAllLinesAsMemory(), fileName, discardCommentsAndWhitespace, stringPool);
+			return FromLines(s.ReadAllLinesAsMemory(), name, discardCommentsAndWhitespace, stringPool);
 		}
 
-		public static List<MiniYamlNode> FromString(string text, string fileName = "<no filename available>", bool discardCommentsAndWhitespace = true, Dictionary<string, string> stringPool = null)
+		public static List<MiniYamlNode> FromString(string text, string name, bool discardCommentsAndWhitespace = true, HashSet<string> stringPool = null)
 		{
-			return FromLines(text.Split(new[] { "\r\n", "\n" }, StringSplitOptions.None).Select(s => s.AsMemory()), fileName, discardCommentsAndWhitespace, stringPool);
+			return FromLines(text.Split(new[] { "\r\n", "\n" }, StringSplitOptions.None).Select(s => s.AsMemory()), name, discardCommentsAndWhitespace, stringPool);
 		}
 
 		public static List<MiniYamlNode> Merge(IEnumerable<IReadOnlyCollection<MiniYamlNode>> sources)
@@ -605,7 +609,8 @@ namespace OpenRA
 				files = files.Append(mapFiles);
 			}
 
-			IEnumerable<IReadOnlyCollection<MiniYamlNode>> yaml = files.Select(s => FromStream(fileSystem.Open(s), s));
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
+			IEnumerable<IReadOnlyCollection<MiniYamlNode>> yaml = files.Select(s => FromStream(fileSystem.Open(s), s, stringPool: stringPool));
 			if (mapRules != null && mapRules.Nodes.Length > 0)
 				yaml = yaml.Append(mapRules.Nodes);
 

OpenRA.Game/ModData.cs

@@ -158,7 +158,8 @@ namespace OpenRA
 
 		public List<MiniYamlNode>[] GetRulesYaml()
 		{
-			return Manifest.Rules.Select(s => MiniYaml.FromStream(DefaultFileSystem.Open(s), s)).ToArray();
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
+			return Manifest.Rules.Select(s => MiniYaml.FromStream(DefaultFileSystem.Open(s), s, stringPool: stringPool)).ToArray();
 		}
 
 		public void Dispose()

OpenRA.Game/Network/GameSave.cs

@@ -122,10 +122,10 @@ namespace OpenRA.Network
 				LastSyncFrame = rs.ReadInt32();
 				lastSyncPacket = rs.ReadBytes(Order.SyncHashOrderLength);
 
-				var globalSettings = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength));
+				var globalSettings = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:globalSettings");
 				GlobalSettings = Session.Global.Deserialize(globalSettings[0].Value);
 
-				var slots = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength));
+				var slots = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:slots");
 				Slots = new Dictionary<string, Session.Slot>();
 				foreach (var s in slots)
 				{
@@ -133,7 +133,7 @@ namespace OpenRA.Network
 					Slots.Add(slot.PlayerReference, slot);
 				}
 
-				var slotClients = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength));
+				var slotClients = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:slotClients");
 				SlotClients = new Dictionary<string, SlotClient>();
 				foreach (var s in slotClients)
 				{
@@ -144,7 +144,7 @@ namespace OpenRA.Network
 				if (rs.Position != traitDataOffset || rs.ReadInt32() != TraitDataMarker)
 					throw new InvalidDataException("Invalid orasav file");
 
-				var traitData = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength));
+				var traitData = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:traitData");
 				foreach (var td in traitData)
 					TraitData.Add(Exts.ParseInt32Invariant(td.Key), td.Value);
 

OpenRA.Game/Network/Handshake.cs

@@ -20,10 +20,10 @@ namespace OpenRA.Network
 		public string Version;
 		public string AuthToken;
 
-		public static HandshakeRequest Deserialize(string data)
+		public static HandshakeRequest Deserialize(string data, string name)
 		{
 			var handshake = new HandshakeRequest();
-			FieldLoader.Load(handshake, MiniYaml.FromString(data).First().Value);
+			FieldLoader.Load(handshake, MiniYaml.FromString(data, name).First().Value);
 			return handshake;
 		}
 
@@ -51,14 +51,14 @@ namespace OpenRA.Network
 		[FieldLoader.Ignore]
 		public Session.Client Client;
 
-		public static HandshakeResponse Deserialize(string data)
+		public static HandshakeResponse Deserialize(string data, string name)
 		{
 			var handshake = new HandshakeResponse
 			{
 				Client = new Session.Client()
 			};
 
-			var ys = MiniYaml.FromString(data);
+			var ys = MiniYaml.FromString(data, name);
 			foreach (var y in ys)
 			{
 				switch (y.Key)

OpenRA.Game/Network/ReplayConnection.cs

@@ -69,7 +69,7 @@ namespace OpenRA.Network
 								if (o.OrderString == "StartGame")
 									IsValid = true;
 								else if (o.OrderString == "SyncInfo" && !IsValid)
-									LobbyInfo = Session.Deserialize(o.TargetString);
+									LobbyInfo = Session.Deserialize(o.TargetString, o.OrderString);
 							}
 						}
 					}

OpenRA.Game/Network/Session.cs

@@ -41,13 +41,13 @@ namespace OpenRA.Network
 			return null;
 		}
 
-		public static Session Deserialize(string data)
+		public static Session Deserialize(string data, string name)
 		{
 			try
 			{
 				var session = new Session();
 
-				var nodes = MiniYaml.FromString(data);
+				var nodes = MiniYaml.FromString(data, name);
 				foreach (var node in nodes)
 				{
 					var strings = node.Key.Split('@');

OpenRA.Game/Network/UnitOrders.cs

@@ -62,7 +62,7 @@ namespace OpenRA.Network
 					if (string.IsNullOrEmpty(order.TargetString))
 						break;
 
-					var yaml = MiniYaml.FromString(order.TargetString);
+					var yaml = MiniYaml.FromString(order.TargetString, order.OrderString);
 					foreach (var node in yaml)
 					{
 						var localizedMessage = new LocalizedMessage(node.Value);
@@ -183,7 +183,7 @@ namespace OpenRA.Network
 
 					if (!string.IsNullOrEmpty(order.TargetString))
 					{
-						var data = MiniYaml.FromString(order.TargetString);
+						var data = MiniYaml.FromString(order.TargetString, order.OrderString);
 						var saveLastOrdersFrame = data.FirstOrDefault(n => n.Key == "SaveLastOrdersFrame");
 						if (saveLastOrdersFrame != null)
 							orderManager.GameSaveLastFrame =
@@ -203,7 +203,7 @@ namespace OpenRA.Network
 
 				case "SaveTraitData":
 				{
-					var data = MiniYaml.FromString(order.TargetString)[0];
+					var data = MiniYaml.FromString(order.TargetString, order.OrderString)[0];
 					var traitIndex = Exts.ParseInt32Invariant(data.Key);
 
 					world?.AddGameSaveTraitData(traitIndex, data.Value);
@@ -244,7 +244,7 @@ namespace OpenRA.Network
 				{
 					// Switch to the server's mod if we need and are able to
 					var mod = Game.ModData.Manifest;
-					var request = HandshakeRequest.Deserialize(order.TargetString);
+					var request = HandshakeRequest.Deserialize(order.TargetString, order.OrderString);
 
 					var externalKey = ExternalMod.MakeKey(request.Mod, request.Version);
 					if ((request.Mod != mod.Id || request.Version != mod.Metadata.Version) &&
@@ -312,7 +312,7 @@ namespace OpenRA.Network
 
 				case "SyncInfo":
 				{
-					orderManager.LobbyInfo = Session.Deserialize(order.TargetString);
+					orderManager.LobbyInfo = Session.Deserialize(order.TargetString, order.OrderString);
 					Game.SyncLobbyInfo();
 					break;
 				}
@@ -320,7 +320,7 @@ namespace OpenRA.Network
 				case "SyncLobbyClients":
 				{
 					var clients = new List<Session.Client>();
-					var nodes = MiniYaml.FromString(order.TargetString);
+					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
 					foreach (var node in nodes)
 					{
 						var strings = node.Key.Split('@');
@@ -336,7 +336,7 @@ namespace OpenRA.Network
 				case "SyncLobbySlots":
 				{
 					var slots = new Dictionary<string, Session.Slot>();
-					var nodes = MiniYaml.FromString(order.TargetString);
+					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
 					foreach (var node in nodes)
 					{
 						var strings = node.Key.Split('@');
@@ -354,7 +354,7 @@ namespace OpenRA.Network
 
 				case "SyncLobbyGlobalSettings":
 				{
-					var nodes = MiniYaml.FromString(order.TargetString);
+					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
 					foreach (var node in nodes)
 					{
 						var strings = node.Key.Split('@');
@@ -368,7 +368,7 @@ namespace OpenRA.Network
 
 				case "SyncConnectionQuality":
 				{
-					var nodes = MiniYaml.FromString(order.TargetString);
+					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
 					foreach (var node in nodes)
 					{
 						var strings = node.Key.Split('@');

OpenRA.Game/Server/Server.cs

@@ -463,7 +463,7 @@ namespace OpenRA.Server
 			Conns.Add(newConn);
 		}
 
-		void ValidateClient(Connection newConn, string data)
+		void ValidateClient(Connection newConn, string data, string name)
 		{
 			try
 			{
@@ -476,7 +476,7 @@ namespace OpenRA.Server
 					return;
 				}
 
-				var handshake = HandshakeResponse.Deserialize(data);
+				var handshake = HandshakeResponse.Deserialize(data, name);
 
 				if (!string.IsNullOrEmpty(Settings.Password) && handshake.Password != Settings.Password)
 				{
@@ -618,10 +618,11 @@ namespace OpenRA.Server
 						try
 						{
 							var httpClient = HttpClientFactory.Create();
-							var httpResponseMessage = await httpClient.GetAsync(playerDatabase.Profile + handshake.Fingerprint);
+							var url = playerDatabase.Profile + handshake.Fingerprint;
+							var httpResponseMessage = await httpClient.GetAsync(url);
 							var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-							var yaml = MiniYaml.FromStream(result).First();
+							var yaml = MiniYaml.FromStream(result, url).First();
 							if (yaml.Key == "Player")
 							{
 								profile = FieldLoader.Load<PlayerProfile>(yaml.Value);
@@ -980,7 +981,7 @@ namespace OpenRA.Server
 				if (!conn.Validated)
 				{
 					if (o.OrderString == "HandshakeResponse")
-						ValidateClient(conn, o.TargetString);
+						ValidateClient(conn, o.TargetString, o.OrderString);
 					else
 					{
 						Log.Write("server", $"Rejected connection from {conn.EndPoint}; Order `{o.OrderString}` is not a `HandshakeResponse`.");
@@ -1015,7 +1016,7 @@ namespace OpenRA.Server
 					{
 						if (GameSave != null)
 						{
-							var data = MiniYaml.FromString(o.TargetString)[0];
+							var data = MiniYaml.FromString(o.TargetString, o.OrderString)[0];
 							GameSave.AddTraitData(OpenRA.Exts.ParseInt32Invariant(data.Key), data.Value);
 						}
 

OpenRA.Game/Widgets/ChromeMetrics.cs

@@ -20,9 +20,10 @@ namespace OpenRA.Widgets
 
 		public static void Initialize(ModData modData)
 		{
-			data = new Dictionary<string, string>();
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			var metrics = MiniYaml.Merge(modData.Manifest.ChromeMetrics.Select(
-				y => MiniYaml.FromStream(modData.DefaultFileSystem.Open(y), y)));
+				y => MiniYaml.FromStream(modData.DefaultFileSystem.Open(y), y, stringPool: stringPool)));
+			data = new Dictionary<string, string>();
 			foreach (var m in metrics)
 				foreach (var n in m.Value.Nodes)
 					data[n.Key] = n.Value.Value;

OpenRA.Game/Widgets/WidgetLoader.cs

@@ -25,7 +25,9 @@ namespace OpenRA
 		{
 			this.modData = modData;
 
-			foreach (var file in modData.Manifest.ChromeLayout.Select(a => MiniYaml.FromStream(modData.DefaultFileSystem.Open(a), a)))
+			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
+			foreach (var file in modData.Manifest.ChromeLayout.Select(
+				a => MiniYaml.FromStream(modData.DefaultFileSystem.Open(a), a, stringPool: stringPool)))
 				foreach (var w in file)
 				{
 					var key = w.Key[(w.Key.IndexOf('@') + 1)..];

OpenRA.Mods.Common/Lint/CheckTranslationReference.cs

@@ -148,7 +148,7 @@ namespace OpenRA.Mods.Common.Lint
 
 			foreach (var filename in modData.Manifest.ChromeLayout)
 			{
-				var nodes = MiniYaml.FromStream(modData.DefaultFileSystem.Open(filename));
+				var nodes = MiniYaml.FromStream(modData.DefaultFileSystem.Open(filename), filename);
 				foreach (var node in nodes)
 					CheckChrome(node, translation, Language, emitError, emitWarning, translatableFields);
 			}

OpenRA.Mods.Common/ServerTraits/LobbyCommands.cs

@@ -1270,7 +1270,7 @@ namespace OpenRA.Mods.Common.Server
 
 				try
 				{
-					server.LobbyInfo = Session.Deserialize(s);
+					server.LobbyInfo = Session.Deserialize(s, nameof(SyncLobby));
 					server.SyncLobbyInfo();
 				}
 				catch (Exception)

OpenRA.Mods.Common/UpdateRules/Rules/20210321/RemovePlaceBuildingPalette.cs

@@ -64,7 +64,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 			}
 
 			if (removed > 0)
-				locations.Add($"{actorNode.Key} ({actorNode.Location.Filename})");
+				locations.Add($"{actorNode.Key} ({actorNode.Location.Name})");
 
 			yield break;
 		}

OpenRA.Mods.Common/UpdateRules/Rules/20210321/RemoveRenderSpritesScale.cs

@@ -23,7 +23,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 		{
 			foreach (var renderSprites in actorNode.ChildrenMatching("RenderSprites"))
 				if (renderSprites.RemoveNodes("Scale") > 0)
-					yield return $"The actor-level scaling has been removed from {actorNode.Key} ({actorNode.Location.Filename}).\n" +
+					yield return $"The actor-level scaling has been removed from {actorNode.Key} ({actorNode.Location.Name}).\n" +
 						"You must manually define Scale on its sequences instead.";
 		}
 	}

OpenRA.Mods.Common/UpdateRules/Rules/20210321/RemoveSmokeTrailWhenDamaged.cs

@@ -40,7 +40,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 
 		public override IEnumerable<string> UpdateActorNode(ModData modData, MiniYamlNodeBuilder actorNode)
 		{
-			var locationKey = $"{actorNode.Key} ({actorNode.Location.Filename})";
+			var locationKey = $"{actorNode.Key} ({actorNode.Location.Name})";
 			var anyConditionalSmokeTrail = false;
 
 			foreach (var smokeTrail in actorNode.ChildrenMatching("SmokeTrailWhenDamaged"))

OpenRA.Mods.Common/UpdateRules/Rules/20210321/ReplaceShadowPalette.cs

@@ -37,7 +37,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 		{
 			foreach (var projectileNode in weaponNode.ChildrenMatching("Projectile"))
 				if (projectileNode.RemoveNodes("ShadowPalette") > 0)
-					locations.Add($"{weaponNode.Key}: {weaponNode.Key} ({weaponNode.Location.Filename})");
+					locations.Add($"{weaponNode.Key}: {weaponNode.Key} ({weaponNode.Location.Name})");
 
 			yield break;
 		}
@@ -46,11 +46,11 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 		{
 			foreach (var node in actorNode.ChildrenMatching("WithShadow"))
 				if (node.RemoveNodes("Palette") > 0)
-					locations.Add($"{actorNode.Key}: {node.Key} ({actorNode.Location.Filename})");
+					locations.Add($"{actorNode.Key}: {node.Key} ({actorNode.Location.Name})");
 
 			foreach (var node in actorNode.ChildrenMatching("WithParachute"))
 				if (node.RemoveNodes("ShadowPalette") > 0)
-					locations.Add($"{actorNode.Key}: {node.Key} ({actorNode.Location.Filename})");
+					locations.Add($"{actorNode.Key}: {node.Key} ({actorNode.Location.Name})");
 
 			yield break;
 		}

OpenRA.Mods.Common/UpdateRules/Rules/20210321/ReplaceWithColoredOverlayPalette.cs

@@ -35,7 +35,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 		{
 			foreach (var node in actorNode.ChildrenMatching("WithColoredOverlay"))
 				if (node.RemoveNodes("Palette") > 0)
-					locations.Add($"{actorNode.Key}: {node.Key} ({actorNode.Location.Filename})");
+					locations.Add($"{actorNode.Key}: {node.Key} ({actorNode.Location.Name})");
 
 			yield break;
 		}

OpenRA.Mods.Common/UpdateRules/Rules/20210321/UnhardcodeVeteranProductionIconOverlay.cs

@@ -40,7 +40,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 			}
 
 			foreach (var producibleWithLevel in actorNode.ChildrenMatching("ProducibleWithLevel"))
-				locations.Add($"{actorNode.Key}: {producibleWithLevel.Key} ({actorNode.Location.Filename})");
+				locations.Add($"{actorNode.Key}: {producibleWithLevel.Key} ({actorNode.Location.Name})");
 
 			yield break;
 		}

OpenRA.Mods.Common/UpdateRules/Rules/20230225/ExplicitSequenceFilenames.cs

@@ -37,7 +37,8 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 		{
 			// Keep a resolved copy of the sequences so we can account for values imported through inheritance or Defaults.
 			// This will be modified during processing, so take a deep copy to avoid side-effects on other update rules.
-			this.resolvedImagesNodes = MiniYaml.FromString(resolvedImagesNodes.WriteToString()).ConvertAll(n => new MiniYamlNodeBuilder(n));
+			this.resolvedImagesNodes = MiniYaml.FromString(resolvedImagesNodes.WriteToString(), nameof(BeforeUpdateSequences))
+				.ConvertAll(n => new MiniYamlNodeBuilder(n));
 
 			var requiredMetadata = new HashSet<string>();
 			foreach (var imageNode in resolvedImagesNodes)
@@ -285,7 +286,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 						imageNode.Value.Nodes.Insert(inheritsNodeIndex, defaultsNode);
 					}
 
-					var nodes = MiniYaml.FromString(duplicateTilesetCount.First(kv => kv.Value == maxDuplicateTilesetCount).Key);
+					var nodes = MiniYaml.FromString(duplicateTilesetCount.First(kv => kv.Value == maxDuplicateTilesetCount).Key, nameof(UpdateSequenceNode));
 					defaultTilesetFilenamesNode = new MiniYamlNodeBuilder("TilesetFilenames", "", nodes);
 					defaultsNode.Value.Nodes.Insert(0, defaultTilesetFilenamesNode);
 				}

OpenRA.Mods.Common/UpdateRules/Rules/20230225/RemoveExperienceFromInfiltrates.cs

@@ -40,7 +40,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 					removed = true;
 
 			if (removed)
-				locations.Add($"{actorNode.Key} ({actorNode.Location.Filename})");
+				locations.Add($"{actorNode.Key} ({actorNode.Location.Name})");
 
 			yield break;
 		}

OpenRA.Mods.Common/UpdateRules/Rules/20230225/RemoveSequenceHasEmbeddedPalette.cs

@@ -48,7 +48,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 			{
 				traitNode.RemoveNodes("Image");
 				traitNode.RemoveNodes("Sequence");
-				locations.Add($"{actorNode.Key} ({actorNode.Location.Filename})");
+				locations.Add($"{actorNode.Key} ({actorNode.Location.Name})");
 			}
 
 			yield break;

OpenRA.Mods.Common/UpdateRules/Rules/20231010/RemoveValidRelationsFromCapturable.cs

@@ -36,7 +36,7 @@ namespace OpenRA.Mods.Common.UpdateRules.Rules
 			foreach (var capturable in actorNode.ChildrenMatching("Capturable"))
 			{
 				if (capturable.RemoveNodes("ValidRelations") > 0)
-					locations.Add($"{actorNode.Key}: {capturable.Key} ({actorNode.Location.Filename})");
+					locations.Add($"{actorNode.Key}: {capturable.Key} ({actorNode.Location.Name})");
 			}
 
 			yield break;

OpenRA.Mods.Common/UpdateRules/UpdateUtils.cs

@@ -35,7 +35,7 @@ namespace OpenRA.Mods.Common.UpdateRules
 					continue;
 				}
 
-				yaml.Add(((IReadWritePackage)package, name, MiniYaml.FromStream(package.GetStream(name), name, false).ConvertAll(n => new MiniYamlNodeBuilder(n))));
+				yaml.Add(((IReadWritePackage)package, name, MiniYaml.FromStream(package.GetStream(name), $"{package.Name}:{name}", false).ConvertAll(n => new MiniYamlNodeBuilder(n))));
 			}
 
 			return yaml;
@@ -68,7 +68,7 @@ namespace OpenRA.Mods.Common.UpdateRules
 			{
 				// Ignore any files that aren't in the map bundle
 				if (!filename.Contains('|') && mapPackage.Contains(filename))
-					fileSet.Add((mapPackage, filename, MiniYaml.FromStream(mapPackage.GetStream(filename), filename, false).ConvertAll(n => new MiniYamlNodeBuilder(n))));
+					fileSet.Add((mapPackage, filename, MiniYaml.FromStream(mapPackage.GetStream(filename), $"{mapPackage.Name}:{filename}", false).ConvertAll(n => new MiniYamlNodeBuilder(n))));
 				else if (modData.ModFiles.Exists(filename))
 					externalFilenames.Add(filename);
 			}
@@ -94,7 +94,7 @@ namespace OpenRA.Mods.Common.UpdateRules
 					return manualSteps;
 				}
 
-				var yaml = new MiniYamlBuilder(null, MiniYaml.FromStream(mapStream, mapPackage.Name, false));
+				var yaml = new MiniYamlBuilder(null, MiniYaml.FromStream(mapStream, $"{mapPackage.Name}:map.yaml", false));
 				files = new YamlFileSet() { (mapPackage, "map.yaml", yaml.Nodes) };
 
 				manualSteps.AddRange(rule.BeforeUpdate(modData));
@@ -170,9 +170,9 @@ namespace OpenRA.Mods.Common.UpdateRules
 				{
 					// Explicit package paths never refer to a map
 					if (!filename.Contains('|') && mapPackage.Contains(filename))
-						return MiniYaml.FromStream(mapPackage.GetStream(filename));
+						return MiniYaml.FromStream(mapPackage.GetStream(filename), $"{mapPackage.Name}:{filename}");
 
-					return MiniYaml.FromStream(fileSystem.Open(filename));
+					return MiniYaml.FromStream(fileSystem.Open(filename), filename);
 				}));
 			}
 
@@ -215,7 +215,7 @@ namespace OpenRA.Mods.Common.UpdateRules
 					if (mapStream == null)
 						continue;
 
-					var yaml = new MiniYamlBuilder(new MiniYaml(null, MiniYaml.FromStream(mapStream, package.Name, false)));
+					var yaml = new MiniYamlBuilder(new MiniYaml(null, MiniYaml.FromStream(mapStream, $"{package.Name}:map.yaml", false)));
 					var mapRulesNode = yaml.NodeWithKeyOrDefault("Rules");
 					if (mapRulesNode != null)
 						foreach (var f in LoadExternalMapYaml(modData, mapRulesNode.Value, externalFilenames))

OpenRA.Mods.Common/UtilityCommands/ExtractYamlStrings.cs

@@ -57,7 +57,7 @@ namespace OpenRA.Mods.Common.UtilityCommands
 					if (mapStream == null)
 						continue;
 
-					var yaml = new MiniYamlBuilder(null, MiniYaml.FromStream(mapStream, package.Name, false));
+					var yaml = new MiniYamlBuilder(null, MiniYaml.FromStream(mapStream, $"{package.Name}:map.yaml", false));
 					var mapRulesNode = yaml.NodeWithKeyOrDefault("Rules");
 					if (mapRulesNode != null)
 						modRules.AddRange(UpdateUtils.LoadExternalMapYaml(modData, mapRulesNode.Value, new HashSet<string>()));
@@ -76,7 +76,7 @@ namespace OpenRA.Mods.Common.UtilityCommands
 					if (mapStream == null)
 						continue;
 
-					var yaml = new MiniYamlBuilder(null, MiniYaml.FromStream(mapStream, package.Name, false));
+					var yaml = new MiniYamlBuilder(null, MiniYaml.FromStream(mapStream, $"{package.Name}:map.yaml", false));
 					var mapRules = new YamlFileSet() { (package, "map.yaml", yaml.Nodes) };
 
 					var mapRulesNode = yaml.NodeWithKeyOrDefault("Rules");

OpenRA.Mods.Common/Widgets/Logic/MissionBrowserLogic.cs

@@ -128,8 +128,9 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 			// Add a group for each campaign
 			if (modData.Manifest.Missions.Length > 0)
 			{
+				var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 				var yaml = MiniYaml.Merge(modData.Manifest.Missions.Select(
-					m => MiniYaml.FromStream(modData.DefaultFileSystem.Open(m), m)));
+					m => MiniYaml.FromStream(modData.DefaultFileSystem.Open(m), m, stringPool: stringPool)));
 
 				foreach (var kv in yaml)
 				{

OpenRA.Mods.Common/Widgets/Logic/PlayerProfileLogic.cs

@@ -166,10 +166,11 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				{
 					var httpClient = HttpClientFactory.Create();
 
-					var httpResponseMessage = await httpClient.GetAsync(playerDatabase.Profile + client.Fingerprint);
+					var url = playerDatabase.Profile + client.Fingerprint;
+					var httpResponseMessage = await httpClient.GetAsync(url);
 					var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-					var yaml = MiniYaml.FromStream(result).First();
+					var yaml = MiniYaml.FromStream(result, url).First();
 					if (yaml.Key == "Player")
 					{
 						profile = FieldLoader.Load<PlayerProfile>(yaml.Value);

OpenRA.Mods.Common/Widgets/Logic/ServerListLogic.cs

@@ -456,7 +456,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 					var httpResponseMessage = await client.GetAsync(queryURL);
 					var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-					var yaml = MiniYaml.FromStream(result);
+					var yaml = MiniYaml.FromStream(result, queryURL);
 					games = new List<GameServer>();
 					foreach (var node in yaml)
 					{
@@ -479,6 +479,7 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 				}
 
 				var lanGames = new List<GameServer>();
+				var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 				foreach (var bl in lanGameLocations)
 				{
 					try
@@ -486,7 +487,8 @@ namespace OpenRA.Mods.Common.Widgets.Logic
 						if (string.IsNullOrEmpty(bl.Data))
 							continue;
 
-						var game = new MiniYamlBuilder(MiniYaml.FromString(bl.Data)[0].Value);
+						var game = new MiniYamlBuilder(MiniYaml.FromString(
+							bl.Data, $"BeaconLocation_{bl.Address}_{bl.LastAdvertised:s}", stringPool: stringPool)[0].Value);
 						var idNode = game.NodeWithKeyOrDefault("Id");
 
 						// Skip beacons created by this instance and replace Id by expected int value

OpenRA.Test/OpenRA.Game/MiniYamlTest.cs

@@ -44,7 +44,7 @@ namespace OpenRA.Test
 	9.1.2: Test
 	9.1.3: # Test
 ";
-			var serialized = MiniYaml.FromString(Yaml, discardCommentsAndWhitespace: false).WriteToString();
+			var serialized = MiniYaml.FromString(Yaml, "", discardCommentsAndWhitespace: false).WriteToString();
 			Console.WriteLine();
 			Assert.That(serialized, Is.EqualTo(Yaml));
 		}
@@ -120,7 +120,7 @@ namespace OpenRA.Test
 	9.1.2: Test
 	9.1.3:
 ";
-			var serialized = MiniYaml.FromString(Yaml).WriteToString();
+			var serialized = MiniYaml.FromString(Yaml, "").WriteToString();
 			Assert.That(serialized, Is.EqualTo(ExpectedYaml));
 		}
 
@@ -152,9 +152,9 @@ Root2:
     Child1:
 		Attribute1: Test
 ";
-			var tabs = MiniYaml.FromString(YamlTabStyle, "yamlTabStyle").WriteToString();
+			var tabs = MiniYaml.FromString(YamlTabStyle, "").WriteToString();
 			Console.WriteLine(tabs);
-			var mixed = MiniYaml.FromString(YamlMixedStyle, "yamlMixedStyle").WriteToString();
+			var mixed = MiniYaml.FromString(YamlMixedStyle, "").WriteToString();
 			Console.WriteLine(mixed);
 			Assert.That(tabs, Is.EqualTo(mixed));
 		}
@@ -376,7 +376,7 @@ TestB:
 	Nothing:
 ";
 
-			var result = MiniYaml.FromString(Yaml).First(n => n.Key == "TestB");
+			var result = MiniYaml.FromString(Yaml, "").First(n => n.Key == "TestB");
 			Assert.AreEqual(5, result.Location.Line);
 		}
 
@@ -549,27 +549,27 @@ Test:
 		[TestCase(TestName = "Comments are correctly separated from values")]
 		public void TestEscapedHashInValues()
 		{
-			var trailingWhitespace = MiniYaml.FromString("key: value # comment", "trailingWhitespace", discardCommentsAndWhitespace: false)[0];
+			var trailingWhitespace = MiniYaml.FromString("key: value # comment", "", discardCommentsAndWhitespace: false)[0];
 			Assert.AreEqual("value", trailingWhitespace.Value.Value);
 			Assert.AreEqual(" comment", trailingWhitespace.Comment);
 
-			var noWhitespace = MiniYaml.FromString("key:value# comment", "noWhitespace", discardCommentsAndWhitespace: false)[0];
+			var noWhitespace = MiniYaml.FromString("key:value# comment", "", discardCommentsAndWhitespace: false)[0];
 			Assert.AreEqual("value", noWhitespace.Value.Value);
 			Assert.AreEqual(" comment", noWhitespace.Comment);
 
-			var escapedHashInValue = MiniYaml.FromString(@"key: before \# after # comment", "escapedHashInValue", discardCommentsAndWhitespace: false)[0];
+			var escapedHashInValue = MiniYaml.FromString(@"key: before \# after # comment", "", discardCommentsAndWhitespace: false)[0];
 			Assert.AreEqual("before # after", escapedHashInValue.Value.Value);
 			Assert.AreEqual(" comment", escapedHashInValue.Comment);
 
-			var emptyValueAndComment = MiniYaml.FromString("key:#", "emptyValueAndComment", discardCommentsAndWhitespace: false)[0];
+			var emptyValueAndComment = MiniYaml.FromString("key:#", "", discardCommentsAndWhitespace: false)[0];
 			Assert.AreEqual(null, emptyValueAndComment.Value.Value);
 			Assert.AreEqual("", emptyValueAndComment.Comment);
 
-			var noValue = MiniYaml.FromString("key:", "noValue", discardCommentsAndWhitespace: false)[0];
+			var noValue = MiniYaml.FromString("key:", "", discardCommentsAndWhitespace: false)[0];
 			Assert.AreEqual(null, noValue.Value.Value);
 			Assert.AreEqual(null, noValue.Comment);
 
-			var emptyKey = MiniYaml.FromString(" : value", "emptyKey", discardCommentsAndWhitespace: false)[0];
+			var emptyKey = MiniYaml.FromString(" : value", "", discardCommentsAndWhitespace: false)[0];
 			Assert.AreEqual(null, emptyKey.Key);
 			Assert.AreEqual("value", emptyKey.Value.Value);
 			Assert.AreEqual(null, emptyKey.Comment);
@@ -579,7 +579,7 @@ Test:
 		public void TestGuardedWhitespace()
 		{
 			const string TestYaml = @"key:   \      test value    \   ";
-			var nodes = MiniYaml.FromString(TestYaml, "testYaml");
+			var nodes = MiniYaml.FromString(TestYaml, "");
 			Assert.AreEqual("      test value    ", nodes[0].Value.Value);
 		}
 
@@ -594,12 +594,12 @@ TestA:
 TestB:
 	Nothing:
 ";
-			var resultDiscard = MiniYaml.FromString(Yaml);
+			var resultDiscard = MiniYaml.FromString(Yaml, "");
 			var resultDiscardLine = resultDiscard.First(n => n.Key == "TestB").Location.Line;
 			Assert.That(resultDiscardLine, Is.EqualTo(6), "Node TestB should report its location as line 6, but is not (discarding comments)");
 			Assert.That(resultDiscard[1].Key, Is.EqualTo("TestB"), "Node TestB should be the second child of the root node, but is not (discarding comments)");
 
-			var resultKeep = MiniYaml.FromString(Yaml, discardCommentsAndWhitespace: false);
+			var resultKeep = MiniYaml.FromString(Yaml, "", discardCommentsAndWhitespace: false);
 			var resultKeepLine = resultKeep.First(n => n.Key == "TestB").Location.Line;
 			Assert.That(resultKeepLine, Is.EqualTo(6), "Node TestB should report its location as line 6, but is not (parsing comments)");
 			Assert.That(resultKeep[4].Key, Is.EqualTo("TestB"), "Node TestB should be the fifth child of the root node, but is not (parsing comments)");
@@ -646,7 +646,7 @@ Parent: # comment without value
 	Seventh: # embedded comment: still a comment # more comment
 ".Replace("\r\n", "\n");
 
-			var result = MiniYaml.FromString(yaml, discardCommentsAndWhitespace: false).WriteToString();
+			var result = MiniYaml.FromString(yaml, "", discardCommentsAndWhitespace: false).WriteToString();
 			Assert.AreEqual(canonicalYaml, result);
 		}
 
@@ -682,7 +682,7 @@ Parent: # comment without value
 	Seventh:
 ".Replace("\r\n", "\n");
 
-			var result = MiniYaml.FromString(Yaml).WriteToString();
+			var result = MiniYaml.FromString(Yaml, "").WriteToString();
 			Assert.AreEqual(strippedYaml, result);
 		}
 	}