Fix IDE0028, IDE0300, IDE0301, IDE0302, IDE0303, IDE0304.

Silence IDE0305.

.editorconfig

@@ -138,7 +138,7 @@ dotnet_diagnostic.IDE0017.severity = warning
 
 # IDE0028 Use collection initializers
 #dotnet_style_collection_initializer = true
-dotnet_diagnostic.IDE0028.severity = suggestion # TODO: Consider enabling
+dotnet_diagnostic.IDE0028.severity = warning
 
 # IDE0029/IDE0030/IDE0270 Use coalesce expression (non-nullable types)/Use coalesce expression (nullable types)/Use coalesce expression (if null)
 #dotnet_style_coalesce_expression = true
@@ -308,27 +308,27 @@ dotnet_diagnostic.IDE0241.severity = warning
 
 # IDE0300 Use collection expression for array
 # From above, uses dotnet_style_prefer_collection_expression
-dotnet_diagnostic.IDE0300.severity = suggestion # TODO: Consider enabling
+dotnet_diagnostic.IDE0300.severity = warning
 
 # IDE0301 Use collection expression for empty
 # From above, uses dotnet_style_prefer_collection_expression
-dotnet_diagnostic.IDE0301.severity = suggestion # TODO: Consider enabling
+dotnet_diagnostic.IDE0301.severity = warning
 
 # IDE0302 Use collection expression for stackalloc
 # From above, uses dotnet_style_prefer_collection_expression
-dotnet_diagnostic.IDE0302.severity = suggestion # TODO: Consider enabling
+dotnet_diagnostic.IDE0302.severity = warning
 
 # IDE0303 Use collection expression for 'Create()'
 # From above, uses dotnet_style_prefer_collection_expression
-dotnet_diagnostic.IDE0303.severity = suggestion # TODO: Consider enabling
+dotnet_diagnostic.IDE0303.severity = warning
 
 # IDE0304 Use collection expression for builder
 # From above, uses dotnet_style_prefer_collection_expression
-dotnet_diagnostic.IDE0304.severity = suggestion # TODO: Consider enabling
+dotnet_diagnostic.IDE0304.severity = warning
 
 # IDE0305 Use collection expression for fluent
 # From above, uses dotnet_style_prefer_collection_expression
-dotnet_diagnostic.IDE0305.severity = suggestion # TODO: Consider enabling
+dotnet_diagnostic.IDE0305.severity = silent
 
 ## Field preferences
 

OpenRA.Game/Actor.cs

@@ -89,21 +89,21 @@ namespace OpenRA
 		sealed class ConditionState
 		{
 			/// <summary>Delegates that have registered to be notified when this condition changes.</summary>
-			public readonly List<VariableObserverNotifier> Notifiers = new();
+			public readonly List<VariableObserverNotifier> Notifiers = [];
 
 			/// <summary>Unique integers identifying granted instances of the condition.</summary>
-			public readonly HashSet<int> Tokens = new();
+			public readonly HashSet<int> Tokens = [];
 		}
 
-		readonly Dictionary<string, ConditionState> conditionStates = new();
+		readonly Dictionary<string, ConditionState> conditionStates = [];
 
 		/// <summary>Each granted condition receives a unique token that is used when revoking.</summary>
-		readonly Dictionary<int, string> conditionTokens = new();
+		readonly Dictionary<int, string> conditionTokens = [];
 
 		int nextConditionToken = 1;
 
 		/// <summary>Cache of condition -> enabled state for quick evaluation of token counter conditions.</summary>
-		readonly Dictionary<string, int> conditionCache = new();
+		readonly Dictionary<string, int> conditionCache = [];
 
 		/// <summary>Read-only version of conditionCache that is passed to IConditionConsumers.</summary>
 		readonly IReadOnlyDictionary<string, int> readOnlyConditionCache;
@@ -541,7 +541,7 @@ namespace OpenRA
 			if (EnabledTargetablePositions.Any())
 				return enabledTargetableWorldPositions;
 
-			return new[] { CenterPosition };
+			return [CenterPosition];
 		}
 
 		#region Conditions

OpenRA.Game/CVec.cs

@@ -62,7 +62,7 @@ namespace OpenRA
 		public override string ToString() { return X + "," + Y; }
 
 		public static readonly CVec[] Directions =
-		{
+		[
 			new(-1, -1),
 			new(-1,  0),
 			new(-1,  1),
@@ -71,7 +71,7 @@ namespace OpenRA
 			new(1, -1),
 			new(1,  0),
 			new(1,  1),
-		};
+		];
 
 		#region Scripting interface
 

OpenRA.Game/CryptoUtil.cs

@@ -20,7 +20,7 @@ namespace OpenRA
 	public static class CryptoUtil
 	{
 		// Fixed byte pattern for the OID header
-		static readonly byte[] OIDHeader = { 0x30, 0xD, 0x6, 0x9, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0xD, 0x1, 0x1, 0x1, 0x5, 0x0 };
+		static readonly byte[] OIDHeader = [0x30, 0xD, 0x6, 0x9, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0xD, 0x1, 0x1, 0x1, 0x5, 0x0];
 
 		static readonly char[] HexUpperAlphabet = "0123456789ABCDEF".ToArray();
 		static readonly char[] HexLowerAlphabet = "0123456789abcdef".ToArray();

OpenRA.Game/ExternalMods.cs

@@ -40,7 +40,7 @@ namespace OpenRA
 
 	public class ExternalMods : IReadOnlyDictionary<string, ExternalMod>
 	{
-		readonly Dictionary<string, ExternalMod> mods = new();
+		readonly Dictionary<string, ExternalMod> mods = [];
 		readonly SheetBuilder sheetBuilder;
 
 		Sheet CreateSheet()
@@ -122,13 +122,13 @@ namespace OpenRA
 				return;
 
 			var key = ExternalMod.MakeKey(mod);
-			var yaml = new MiniYamlNode("Registration", new MiniYaml("", new[]
-			{
+			var yaml = new MiniYamlNode("Registration", new MiniYaml("",
+			[
 				new MiniYamlNode("Id", mod.Id),
 				new MiniYamlNode("Version", mod.Metadata.Version),
 				new MiniYamlNode("LaunchPath", launchPath),
 				new MiniYamlNode("LaunchArgs", new[] { "Game.Mod=" + mod.Id }.Concat(launchArgs).JoinWith(", "))
-			}));
+			]));
 
 			var iconNodes = new List<MiniYamlNode>();
 

OpenRA.Game/Exts.cs

@@ -413,11 +413,6 @@ namespace OpenRA
 			return ts.Except(exclusions);
 		}
 
-		public static HashSet<T> ToHashSet<T>(this IEnumerable<T> source)
-		{
-			return new HashSet<T>(source);
-		}
-
 		public static Dictionary<TKey, TSource> ToDictionaryWithConflictLog<TSource, TKey>(
 			this IEnumerable<TSource> source, Func<TSource, TKey> keySelector,
 			string debugName, Func<TKey, string> logKey, Func<TSource, string> logValue)
@@ -460,14 +455,14 @@ namespace OpenRA
 				// Check for a key conflict:
 				if (!output.TryAdd(key, element))
 				{
-					dupKeys ??= new Dictionary<TKey, List<string>>();
+					dupKeys ??= [];
 					if (!dupKeys.TryGetValue(key, out var dupKeyMessages))
 					{
 						// Log the initial conflicting value already inserted:
-						dupKeyMessages = new List<string>
-						{
+						dupKeyMessages =
+						[
 							logValue(output[key])
-						};
+						];
 						dupKeys.Add(key, dupKeyMessages);
 					}
 
@@ -664,7 +659,7 @@ namespace OpenRA
 			if (index == -1)
 			{
 				// The remaining string is an empty string
-				str = ReadOnlySpan<char>.Empty;
+				str = [];
 				Current = span;
 				return true;
 			}

OpenRA.Game/FieldLoader.cs

@@ -530,8 +530,8 @@ namespace OpenRA
 			if (value != null)
 			{
 				var parts = value.Split(SplitComma, StringSplitOptions.RemoveEmptyEntries);
-				var ctor = fieldType.GetConstructor(new[] { typeof(string[]) });
-				return ctor.Invoke(new object[] { parts.Select(p => p.Trim()).ToArray() });
+				var ctor = fieldType.GetConstructor([typeof(string[])]);
+				return ctor.Invoke([parts.Select(p => p.Trim()).ToArray()]);
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -544,7 +544,7 @@ namespace OpenRA
 
 			var innerType = fieldType.GetGenericArguments()[0];
 			var innerValue = GetValue("Nullable<T>", innerType, value, field);
-			return fieldType.GetConstructor(new[] { innerType }).Invoke(new[] { innerValue });
+			return fieldType.GetConstructor([innerType]).Invoke([innerValue]);
 		}
 
 		public static void Load(object self, MiniYaml my)
@@ -565,7 +565,7 @@ namespace OpenRA
 						val = fli.Loader(my);
 					else
 					{
-						missing ??= new List<string>();
+						missing ??= [];
 						missing.Add(fli.YamlName);
 						continue;
 					}
@@ -576,7 +576,7 @@ namespace OpenRA
 					{
 						if (fli.Attribute.Required)
 						{
-							missing ??= new List<string>();
+							missing ??= [];
 							missing.Add(fli.YamlName);
 						}
 

OpenRA.Game/FileFormats/Png.cs

@@ -25,14 +25,14 @@ namespace OpenRA.FileFormats
 {
 	public class Png
 	{
-		static readonly byte[] Signature = { 0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a };
+		static readonly byte[] Signature = [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a];
 
 		public int Width { get; }
 		public int Height { get; }
 		public Color[] Palette { get; }
 		public byte[] Data { get; }
 		public SpriteFrameType Type { get; }
-		public Dictionary<string, string> EmbeddedData = new();
+		public Dictionary<string, string> EmbeddedData = [];
 
 		public int PixelStride => Type == SpriteFrameType.Indexed8 ? 1 : Type == SpriteFrameType.Rgb24 ? 3 : 4;
 

OpenRA.Game/FileSystem/FileSystem.cs

@@ -29,16 +29,16 @@ namespace OpenRA.FileSystem
 	public class FileSystem : IReadOnlyFileSystem
 	{
 		public IEnumerable<IReadOnlyPackage> MountedPackages => mountedPackages.Keys;
-		readonly Dictionary<IReadOnlyPackage, int> mountedPackages = new();
-		readonly Dictionary<string, IReadOnlyPackage> explicitMounts = new();
+		readonly Dictionary<IReadOnlyPackage, int> mountedPackages = [];
+		readonly Dictionary<string, IReadOnlyPackage> explicitMounts = [];
 		readonly string modID;
 
 		// Mod packages that should not be disposed
-		readonly List<IReadOnlyPackage> modPackages = new();
+		readonly List<IReadOnlyPackage> modPackages = [];
 		readonly IReadOnlyDictionary<string, Manifest> installedMods;
 		readonly IPackageLoader[] packageLoaders;
 
-		Cache<string, List<IReadOnlyPackage>> fileIndex = new(_ => new List<IReadOnlyPackage>());
+		Cache<string, List<IReadOnlyPackage>> fileIndex = new(_ => []);
 
 		public FileSystem(string modID, IReadOnlyDictionary<string, Manifest> installedMods, IPackageLoader[] packageLoaders)
 		{
@@ -178,7 +178,7 @@ namespace OpenRA.FileSystem
 			explicitMounts.Clear();
 			modPackages.Clear();
 
-			fileIndex = new Cache<string, List<IReadOnlyPackage>>(_ => new List<IReadOnlyPackage>());
+			fileIndex = new Cache<string, List<IReadOnlyPackage>>(_ => []);
 		}
 
 		public void TrimExcess()

OpenRA.Game/FluentBundle.cs

@@ -128,7 +128,7 @@ namespace OpenRA
 						throw new ArgumentException("Expected a comma separated list of name, value arguments " +
 							"but the number of arguments is not a multiple of two", nameof(args));
 
-					fluentArgs = new Dictionary<string, IFluentType>();
+					fluentArgs = [];
 					for (var i = 0; i < args.Length; i += 2)
 					{
 						var argKey = args[i] as string;

OpenRA.Game/Game.cs

@@ -356,7 +356,7 @@ namespace OpenRA
 			var explicitModPaths = Array.Empty<string>();
 			if (modID != null && (File.Exists(modID) || Directory.Exists(modID)))
 			{
-				explicitModPaths = new[] { modID };
+				explicitModPaths = [modID];
 				modID = Path.GetFileNameWithoutExtension(modID);
 			}
 
@@ -402,7 +402,7 @@ namespace OpenRA
 			var modSearchArg = args.GetValue("Engine.ModSearchPaths", null);
 			var modSearchPaths = modSearchArg != null ?
 				FieldLoader.GetValue<string[]>("Engine.ModsPath", modSearchArg) :
-				new[] { Path.Combine(Platform.EngineDir, "mods") };
+				[Path.Combine(Platform.EngineDir, "mods")];
 
 			Mods = new InstalledMods(modSearchPaths, explicitModPaths);
 			Console.WriteLine("Internal mods:");

OpenRA.Game/GameInformation.cs

@@ -39,7 +39,7 @@ namespace OpenRA
 		public TimeSpan Duration => EndTimeUtc > StartTimeUtc ? EndTimeUtc - StartTimeUtc : TimeSpan.Zero;
 
 		public IList<Player> Players { get; }
-		public HashSet<int> DisabledSpawnPoints = new();
+		public HashSet<int> DisabledSpawnPoints = [];
 		public MapPreview MapPreview => Game.ModData.MapCache[MapUid];
 		public IEnumerable<Player> HumanPlayers { get { return Players.Where(p => p.IsHuman); } }
 		public bool IsSinglePlayer => HumanPlayers.Count() == 1;
@@ -48,8 +48,8 @@ namespace OpenRA
 
 		public GameInformation()
 		{
-			Players = new List<Player>();
-			playersByRuntime = new Dictionary<OpenRA.Player, Player>();
+			Players = [];
+			playersByRuntime = [];
 		}
 
 		public static GameInformation Deserialize(string data, string path)

OpenRA.Game/GameRules/ActorInfo.cs

@@ -32,7 +32,7 @@ namespace OpenRA
 		/// You can remove inherited traits by adding a - in front of them as in -TraitName: to inherit everything, but this trait.
 		/// </summary>
 		public readonly string Name;
-		readonly TypeDictionary traits = new();
+		readonly TypeDictionary traits = [];
 		TraitInfo[] constructOrderCache = null;
 
 		public ActorInfo(ObjectCreator creator, string name, MiniYaml node)

OpenRA.Game/GameRules/SoundInfo.cs

@@ -17,14 +17,14 @@ namespace OpenRA.GameRules
 {
 	public class SoundInfo
 	{
-		public readonly Dictionary<string, string[]> Variants = new();
-		public readonly Dictionary<string, string[]> Prefixes = new();
-		public readonly Dictionary<string, string[]> Voices = new();
-		public readonly Dictionary<string, string[]> Notifications = new();
+		public readonly Dictionary<string, string[]> Variants = [];
+		public readonly Dictionary<string, string[]> Prefixes = [];
+		public readonly Dictionary<string, string[]> Voices = [];
+		public readonly Dictionary<string, string[]> Notifications = [];
 		public readonly string DefaultVariant = ".aud";
 		public readonly string DefaultPrefix = "";
-		public readonly HashSet<string> DisableVariants = new();
-		public readonly HashSet<string> DisablePrefixes = new();
+		public readonly HashSet<string> DisableVariants = [];
+		public readonly HashSet<string> DisablePrefixes = [];
 
 		public readonly Lazy<Dictionary<string, SoundPool>> VoicePools;
 		public readonly Lazy<Dictionary<string, SoundPool>> NotificationsPools;
@@ -69,7 +69,7 @@ namespace OpenRA.GameRules
 		public readonly float VolumeModifier;
 		public readonly InterruptType Type;
 		readonly string[] clips;
-		readonly List<string> liveclips = new();
+		readonly List<string> liveclips = [];
 
 		public SoundPool(float volumeModifier, InterruptType interruptType, params string[] clips)
 		{

OpenRA.Game/GameRules/WeaponInfo.cs

@@ -36,7 +36,7 @@ namespace OpenRA.GameRules
 	public class WarheadArgs
 	{
 		public WeaponInfo Weapon;
-		public int[] DamageModifiers = Array.Empty<int>();
+		public int[] DamageModifiers = [];
 		public WPos? Source;
 		public WRot ImpactOrientation;
 		public WPos ImpactPosition;
@@ -116,7 +116,7 @@ namespace OpenRA.GameRules
 
 		[Desc("Delay in ticks between firing shots from the same ammo magazine. If one entry, it will be used for all bursts.",
 			"If multiple entries, their number needs to match Burst - 1.")]
-		public readonly int[] BurstDelays = { 5 };
+		public readonly int[] BurstDelays = [5];
 
 		[Desc("The minimum range the weapon can fire.")]
 		public readonly WDist MinRange = WDist.Zero;
@@ -128,7 +128,7 @@ namespace OpenRA.GameRules
 		public readonly IProjectileInfo Projectile;
 
 		[FieldLoader.LoadUsing(nameof(LoadWarheads))]
-		public readonly List<IWarhead> Warheads = new();
+		public readonly List<IWarhead> Warheads = [];
 
 		/// <summary>
 		/// This constructor is used solely for documentation generation.
@@ -139,7 +139,7 @@ namespace OpenRA.GameRules
 		{
 			// Resolve any weapon-level yaml inheritance or removals
 			// HACK: The "Defaults" sequence syntax prevents us from doing this generally during yaml parsing
-			content = content.WithNodes(MiniYaml.Merge(new IReadOnlyCollection<MiniYamlNode>[] { content.Nodes }));
+			content = content.WithNodes(MiniYaml.Merge([content.Nodes]));
 			FieldLoader.Load(this, content);
 		}
 

OpenRA.Game/Graphics/Animation.cs

@@ -73,10 +73,10 @@ namespace OpenRA.Graphics
 					shadow, pos, offset - new WVec(0, 0, height), CurrentSequence.ShadowZOffset + zOffset + height, palette,
 					CurrentSequence.Scale, 1f, float3.Ones, tintModifiers,
 					true, rotation);
-				return new IRenderable[] { shadowRenderable, imageRenderable };
+				return [shadowRenderable, imageRenderable];
 			}
 
-			return new IRenderable[] { imageRenderable };
+			return [imageRenderable];
 		}
 
 		public IRenderable[] RenderUI(WorldRenderer wr, int2 pos, in WVec offset, int zOffset, PaletteReference palette, float scale = 1f, float rotation = 0f)
@@ -92,10 +92,10 @@ namespace OpenRA.Graphics
 			{
 				var shadowPos = pos - new int2((int)(scale * shadow.Size.X / 2), (int)(scale * shadow.Size.Y / 2));
 				var shadowRenderable = new UISpriteRenderable(shadow, WPos.Zero + offset, shadowPos, CurrentSequence.ShadowZOffset + zOffset, palette, scale, 1f, rotation);
-				return new IRenderable[] { shadowRenderable, imageRenderable };
+				return [shadowRenderable, imageRenderable];
 			}
 
-			return new IRenderable[] { imageRenderable };
+			return [imageRenderable];
 		}
 
 		public Rectangle ScreenBounds(WorldRenderer wr, WPos pos, in WVec offset)

OpenRA.Game/Graphics/ChromeProvider.cs

@@ -49,7 +49,7 @@ namespace OpenRA.Graphics
 
 			public readonly int[] PanelRegion = null;
 			public readonly PanelSides PanelSides = PanelSides.All;
-			public readonly Dictionary<string, Rectangle> Regions = new();
+			public readonly Dictionary<string, Rectangle> Regions = [];
 		}
 
 		public static IReadOnlyDictionary<string, Collection> Collections => collections;
@@ -71,11 +71,11 @@ namespace OpenRA.Graphics
 				dpiScale = Game.Renderer.WindowScale;
 
 			fileSystem = modData.DefaultFileSystem;
-			collections = new Dictionary<string, Collection>();
-			cachedSheets = new Dictionary<string, (Sheet, int)>();
-			cachedSprites = new Dictionary<string, Dictionary<string, Sprite>>();
-			cachedPanelSprites = new Dictionary<string, Sprite[]>();
-			cachedCollectionSheets = new Dictionary<Collection, (Sheet, int)>();
+			collections = [];
+			cachedSheets = [];
+			cachedSprites = [];
+			cachedPanelSprites = [];
+			cachedCollectionSheets = [];
 
 			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			var chrome = MiniYaml.Merge(modData.Manifest.Chrome
@@ -170,7 +170,7 @@ namespace OpenRA.Graphics
 			var sheetDensity = SheetForCollection(collection);
 			if (cachedCollection == null)
 			{
-				cachedCollection = new Dictionary<string, Sprite>();
+				cachedCollection = [];
 				cachedSprites.Add(collectionName, cachedCollection);
 			}
 
@@ -240,11 +240,11 @@ namespace OpenRA.Graphics
 				// PERF: We don't need to search for images if there are no definitions.
 				// PERF: It's more efficient to send an empty array rather than an array of 9 nulls.
 				if (collection.Regions.Count == 0)
-					return Array.Empty<Sprite>();
+					return [];
 
 				// Support manual definitions for unusual dialog layouts
-				sprites = new[]
-				{
+				sprites =
+				[
 					TryGetImage(collectionName, "corner-tl"),
 					TryGetImage(collectionName, "border-t"),
 					TryGetImage(collectionName, "corner-tr"),
@@ -254,7 +254,7 @@ namespace OpenRA.Graphics
 					TryGetImage(collectionName, "corner-bl"),
 					TryGetImage(collectionName, "border-b"),
 					TryGetImage(collectionName, "corner-br")
-				};
+				];
 			}
 
 			cachedPanelSprites.Add(collectionName, sprites);

OpenRA.Game/Graphics/CursorManager.cs

@@ -29,7 +29,7 @@ namespace OpenRA.Graphics
 			public IHardwareCursor[] Cursors;
 		}
 
-		readonly Dictionary<string, Cursor> cursors = new();
+		readonly Dictionary<string, Cursor> cursors = [];
 		readonly SheetBuilder sheetBuilder;
 		readonly GraphicSettings graphicSettings;
 
@@ -233,7 +233,7 @@ namespace OpenRA.Graphics
 			var height = frame.Size.Height;
 
 			if (width == 0 || height == 0)
-				return Array.Empty<byte>();
+				return [];
 
 			var data = new byte[4 * width * height];
 			unsafe

OpenRA.Game/Graphics/HardwarePalette.cs

@@ -21,11 +21,11 @@ namespace OpenRA.Graphics
 		public ITexture ColorShifts { get; }
 
 		public int Height { get; private set; }
-		readonly Dictionary<string, ImmutablePalette> palettes = new();
-		readonly Dictionary<string, MutablePalette> mutablePalettes = new();
-		readonly Dictionary<string, int> indices = new();
-		byte[] buffer = Array.Empty<byte>();
-		float[] colorShiftBuffer = Array.Empty<float>();
+		readonly Dictionary<string, ImmutablePalette> palettes = [];
+		readonly Dictionary<string, MutablePalette> mutablePalettes = [];
+		readonly Dictionary<string, int> indices = [];
+		byte[] buffer = [];
+		float[] colorShiftBuffer = [];
 
 		public HardwarePalette()
 		{

OpenRA.Game/Graphics/ModelVertex.cs

@@ -43,11 +43,11 @@ namespace OpenRA.Graphics
 			: base("model")
 		{ }
 
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
+		public override ShaderVertexAttribute[] Attributes { get; } =
+		[
 			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 3, 0),
 			new ShaderVertexAttribute("aVertexTexCoord", ShaderVertexAttributeType.Float, 4, 12),
 			new ShaderVertexAttribute("aVertexTexMetadata", ShaderVertexAttributeType.Float, 2, 28),
-		};
+		];
 	}
 }

OpenRA.Game/Graphics/RenderPostProcessPassVertex.cs

@@ -43,10 +43,10 @@ namespace OpenRA.Graphics
 		public RenderPostProcessPassShaderBindings(string name)
 			: base("postprocess", "postprocess_" + name) { }
 
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
+		public override ShaderVertexAttribute[] Attributes { get; } =
+		[
 			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 2, 0)
-		};
+		];
 	}
 
 	public sealed class RenderPostProcessPassTexturedShaderBindings : ShaderBindings
@@ -55,10 +55,10 @@ namespace OpenRA.Graphics
 			: base("postprocess_textured", "postprocess_textured_" + name)
 		{ }
 
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
+		public override ShaderVertexAttribute[] Attributes { get; } =
+		[
 			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 2, 0),
 			new ShaderVertexAttribute("aVertexTexCoord", ShaderVertexAttributeType.Float, 2, 8),
-		};
+		];
 	}
 }

OpenRA.Game/Graphics/RgbaColorRenderer.cs

@@ -191,7 +191,7 @@ namespace OpenRA.Graphics
 		{
 			var tr = new float3(br.X, tl.Y, tl.Z);
 			var bl = new float3(tl.X, br.Y, br.Z);
-			DrawPolygon(new[] { tl, tr, br, bl }, width, color, blendMode);
+			DrawPolygon([tl, tr, br, bl], width, color, blendMode);
 		}
 
 		public void FillRect(in float3 tl, in float3 br, Color color, BlendMode blendMode = BlendMode.Alpha)

OpenRA.Game/Graphics/SheetBuilder.cs

@@ -33,7 +33,7 @@ namespace OpenRA.Graphics
 	public sealed class SheetBuilder : IDisposable
 	{
 		public readonly SheetType Type;
-		readonly List<Sheet> sheets = new();
+		readonly List<Sheet> sheets = [];
 		readonly Func<Sheet> allocateSheet;
 		readonly int margin;
 		int rowHeight = 0;

OpenRA.Game/Graphics/SpriteCache.cs

@@ -27,12 +27,12 @@ namespace OpenRA.Graphics
 
 		readonly Dictionary<
 			int,
-			(int[] Frames, MiniYamlNode.SourceLocation Location, AdjustFrame AdjustFrame, bool Premultiplied)> spriteReservations = new();
-		readonly Dictionary<string, List<int>> reservationsByFilename = new();
+			(int[] Frames, MiniYamlNode.SourceLocation Location, AdjustFrame AdjustFrame, bool Premultiplied)> spriteReservations = [];
+		readonly Dictionary<string, List<int>> reservationsByFilename = [];
 
-		readonly Dictionary<int, Sprite[]> resolvedSprites = new();
+		readonly Dictionary<int, Sprite[]> resolvedSprites = [];
 
-		readonly Dictionary<int, (string Filename, MiniYamlNode.SourceLocation Location)> missingFiles = new();
+		readonly Dictionary<int, (string Filename, MiniYamlNode.SourceLocation Location)> missingFiles = [];
 
 		int nextReservationToken = 1;
 
@@ -54,7 +54,7 @@ namespace OpenRA.Graphics
 		{
 			var token = nextReservationToken++;
 			spriteReservations[token] = (frames?.ToArray(), location, adjustFrame, premultiplied);
-			reservationsByFilename.GetOrAdd(filename, _ => new List<int>()).Add(token);
+			reservationsByFilename.GetOrAdd(filename, _ => []).Add(token);
 			return token;
 		}
 

OpenRA.Game/Graphics/SpriteRenderable.cs

@@ -9,7 +9,6 @@
  */
 #endregion
 
-using System;
 using System.Collections.Generic;
 using OpenRA.Primitives;
 
@@ -17,7 +16,7 @@ namespace OpenRA.Graphics
 {
 	public class SpriteRenderable : IPalettedRenderable, IModifyableRenderable, IFinalizedRenderable
 	{
-		public static readonly IEnumerable<IRenderable> None = Array.Empty<IRenderable>();
+		public static readonly IEnumerable<IRenderable> None = [];
 
 		readonly Sprite sprite;
 		readonly WPos pos;

OpenRA.Game/Graphics/TerrainSpriteLayer.cs

@@ -19,7 +19,7 @@ namespace OpenRA.Graphics
 	public sealed class TerrainSpriteLayer : IDisposable
 	{
 		// PERF: we can reuse the IndexBuffer as all layers have the same size.
-		static readonly ConditionalWeakTable<World, IndexBufferRc> IndexBuffers = new();
+		static readonly ConditionalWeakTable<World, IndexBufferRc> IndexBuffers = [];
 		readonly IndexBufferRc indexBufferWrapper;
 
 		public readonly BlendMode BlendMode;
@@ -30,7 +30,7 @@ namespace OpenRA.Graphics
 		readonly IVertexBuffer<Vertex> vertexBuffer;
 		readonly Vertex[] vertices;
 		readonly bool[] ignoreTint;
-		readonly HashSet<int> dirtyRows = new();
+		readonly HashSet<int> dirtyRows = [];
 		readonly int indexRowStride;
 		readonly int vertexRowStride;
 		readonly bool restrictToBounds;

OpenRA.Game/Graphics/Util.cs

@@ -19,12 +19,12 @@ namespace OpenRA.Graphics
 	public static class Util
 	{
 		// yes, our channel order is nuts.
-		static readonly int[] ChannelMasks = { 2, 1, 0, 3 };
+		static readonly int[] ChannelMasks = [2, 1, 0, 3];
 
 		public static uint[] CreateQuadIndices(int quads)
 		{
 			var indices = new uint[quads * 6];
-			ReadOnlySpan<uint> cornerVertexMap = stackalloc uint[] { 0, 1, 2, 2, 3, 0 };
+			ReadOnlySpan<uint> cornerVertexMap = [0, 1, 2, 2, 3, 0];
 			for (var i = 0; i < indices.Length; i++)
 				indices[i] = cornerVertexMap[i % 6] + (uint)(4 * (i / 6));
 
@@ -277,13 +277,13 @@ namespace OpenRA.Graphics
 				size.X * angleSin - size.Y * angleCos,
 				(size.X * angleSin - size.Y * angleCos) * size.Z / size.Y);
 
-			return new float3[]
-			{
+			return
+			[
 				center - ra,
 				center + rb,
 				center + ra,
 				center - rb
-			};
+			];
 		}
 
 		/// <summary>

OpenRA.Game/Graphics/Vertex.cs

@@ -53,12 +53,12 @@ namespace OpenRA.Graphics
 			: base("combined")
 		{ }
 
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
+		public override ShaderVertexAttribute[] Attributes { get; } =
+		[
 			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 3, 0),
 			new ShaderVertexAttribute("aVertexTexCoord", ShaderVertexAttributeType.Float, 4, 12),
 			new ShaderVertexAttribute("aVertexAttributes", ShaderVertexAttributeType.UInt, 1, 28),
 			new ShaderVertexAttribute("aVertexTint", ShaderVertexAttributeType.Float, 4, 32)
-		};
+		];
 	}
 }

OpenRA.Game/Graphics/WorldRenderer.cs

@@ -31,19 +31,19 @@ namespace OpenRA.Graphics
 
 		public event Action PaletteInvalidated = null;
 
-		readonly HashSet<Actor> onScreenActors = new();
+		readonly HashSet<Actor> onScreenActors = [];
 		readonly HardwarePalette palette = new();
-		readonly Dictionary<string, PaletteReference> palettes = new();
+		readonly Dictionary<string, PaletteReference> palettes = [];
 		readonly IRenderTerrain terrainRenderer;
 		readonly Lazy<DebugVisualizations> debugVis;
 		readonly Func<string, PaletteReference> createPaletteReference;
 		readonly bool enableDepthBuffer;
 
-		readonly List<IFinalizedRenderable> preparedRenderables = new();
-		readonly List<IFinalizedRenderable> preparedOverlayRenderables = new();
-		readonly List<IFinalizedRenderable> preparedAnnotationRenderables = new();
+		readonly List<IFinalizedRenderable> preparedRenderables = [];
+		readonly List<IFinalizedRenderable> preparedOverlayRenderables = [];
+		readonly List<IFinalizedRenderable> preparedAnnotationRenderables = [];
 
-		readonly List<IRenderable> renderablesBuffer = new();
+		readonly List<IRenderable> renderablesBuffer = [];
 		readonly IRenderer[] renderers;
 		readonly IRenderPostProcessPass[] postProcessPasses;
 
@@ -429,7 +429,7 @@ namespace OpenRA.Graphics
 		public float[] ScreenVector(in WVec vec)
 		{
 			var xyz = ScreenVectorComponents(vec);
-			return new[] { xyz.X, xyz.Y, xyz.Z, 1f };
+			return [xyz.X, xyz.Y, xyz.Z, 1f];
 		}
 
 		public int2 ScreenPxOffset(in WVec vec)

OpenRA.Game/HotkeyDefinition.cs

@@ -24,10 +24,10 @@ namespace OpenRA
 		[FluentReference]
 		public readonly string Description = "";
 
-		public readonly HashSet<string> Types = new();
+		public readonly HashSet<string> Types = [];
 
 		[FluentReference]
-		public readonly HashSet<string> Contexts = new();
+		public readonly HashSet<string> Contexts = [];
 
 		public readonly bool Readonly = false;
 		public bool HasDuplicates { get; internal set; }

OpenRA.Game/HotkeyManager.cs

@@ -18,8 +18,8 @@ namespace OpenRA
 	public sealed class HotkeyManager
 	{
 		readonly Dictionary<string, Hotkey> settings;
-		readonly Dictionary<string, HotkeyDefinition> definitions = new();
-		readonly Dictionary<string, Hotkey> keys = new();
+		readonly Dictionary<string, HotkeyDefinition> definitions = [];
+		readonly Dictionary<string, Hotkey> keys = [];
 
 		public HotkeyManager(IReadOnlyFileSystem fileSystem, Dictionary<string, Hotkey> settings, Manifest manifest)
 		{

OpenRA.Game/Manifest.cs

@@ -78,11 +78,11 @@ namespace OpenRA
 		public readonly MiniYaml LoadScreen;
 		public readonly string DefaultOrderGenerator;
 
-		public readonly string[] Assemblies = Array.Empty<string>();
-		public readonly string[] SoundFormats = Array.Empty<string>();
-		public readonly string[] SpriteFormats = Array.Empty<string>();
-		public readonly string[] PackageFormats = Array.Empty<string>();
-		public readonly string[] VideoFormats = Array.Empty<string>();
+		public readonly string[] Assemblies = [];
+		public readonly string[] SoundFormats = [];
+		public readonly string[] SpriteFormats = [];
+		public readonly string[] PackageFormats = [];
+		public readonly string[] VideoFormats = [];
 		public readonly int FontSheetSize = 512;
 		public readonly int CursorSheetSize = 512;
 
@@ -91,15 +91,15 @@ namespace OpenRA
 		public readonly bool AllowUnusedFluentMessagesInExternalPackages = true;
 
 		readonly string[] reservedModuleNames =
-		{
+		[
 			"Include", "Metadata", "FileSystem", "MapFolders", "Rules",
 			"Sequences", "ModelSequences", "Cursors", "Chrome", "Assemblies", "ChromeLayout", "Weapons",
 			"Voices", "Notifications", "Music", "FluentMessages", "TileSets", "ChromeMetrics", "Missions", "Hotkeys",
 			"ServerTraits", "LoadScreen", "DefaultOrderGenerator", "SupportsMapsFrom", "SoundFormats", "SpriteFormats", "VideoFormats",
 			"RequiresMods", "PackageFormats", "AllowUnusedFluentMessagesInExternalPackages", "FontSheetSize", "CursorSheetSize"
-		};
+		];
 
-		readonly TypeDictionary modules = new();
+		readonly TypeDictionary modules = [];
 		readonly Dictionary<string, MiniYaml> yaml;
 
 		bool customDataLoaded;
@@ -127,7 +127,7 @@ namespace OpenRA
 			}
 
 			// Merge inherited overrides
-			yaml = new MiniYaml(null, MiniYaml.Merge(new[] { nodes })).ToDictionary();
+			yaml = new MiniYaml(null, MiniYaml.Merge([nodes])).ToDictionary();
 
 			Metadata = FieldLoader.Load<ModMetadata>(yaml["Metadata"]);
 
@@ -207,11 +207,11 @@ namespace OpenRA
 					throw new InvalidDataException($"`{kv.Key}` is not a valid mod manifest entry.");
 
 				IGlobalModData module;
-				var ctor = t.GetConstructor(new[] { typeof(MiniYaml) });
+				var ctor = t.GetConstructor([typeof(MiniYaml)]);
 				if (ctor != null)
 				{
 					// Class has opted-in to DIY initialization
-					module = (IGlobalModData)ctor.Invoke(new object[] { kv.Value });
+					module = (IGlobalModData)ctor.Invoke([kv.Value]);
 				}
 				else
 				{
@@ -229,7 +229,7 @@ namespace OpenRA
 		static string[] YamlList(Dictionary<string, MiniYaml> yaml, string key)
 		{
 			if (!yaml.TryGetValue(key, out var value))
-				return Array.Empty<string>();
+				return [];
 
 			return value.Nodes.Select(n => n.Key).ToArray();
 		}
@@ -279,11 +279,11 @@ namespace OpenRA
 			}
 
 			IGlobalModData module;
-			var ctor = t.GetConstructor(new[] { typeof(MiniYaml) });
+			var ctor = t.GetConstructor([typeof(MiniYaml)]);
 			if (ctor != null)
 			{
 				// Class has opted-in to DIY initialization
-				module = (IGlobalModData)ctor.Invoke(new object[] { data.Value });
+				module = (IGlobalModData)ctor.Invoke([data.Value]);
 			}
 			else
 			{

OpenRA.Game/Map/ActorReference.cs

@@ -74,11 +74,11 @@ namespace OpenRA
 			if (initInstance.Length > 1)
 				type.GetField(nameof(ActorInit.InstanceName)).SetValue(init, initInstance[1]);
 
-			var loader = type.GetMethod("Initialize", new[] { typeof(MiniYaml) });
+			var loader = type.GetMethod("Initialize", [typeof(MiniYaml)]);
 			if (loader == null)
 				throw new InvalidDataException($"{initInstance[0]}Init does not define a yaml-assignable type.");
 
-			loader.Invoke(init, new[] { initYaml });
+			loader.Invoke(init, [initYaml]);
 			return init;
 		}
 

OpenRA.Game/Map/Map.cs

@@ -11,7 +11,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Collections.Immutable;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -158,7 +157,7 @@ namespace OpenRA
 
 		/// <summary>Defines the order of the fields in map.yaml.</summary>
 		static readonly MapField[] YamlFields =
-		{
+		[
 			new("MapFormat"),
 			new("RequiresMod"),
 			new("Title"),
@@ -179,7 +178,7 @@ namespace OpenRA
 			new("Voices", nameof(VoiceDefinitions), required: false),
 			new("Music", nameof(MusicDefinitions), required: false),
 			new("Notifications", nameof(NotificationDefinitions), required: false),
-		};
+		];
 
 		// Format versions
 		public int MapFormat { get; private set; }
@@ -193,13 +192,13 @@ namespace OpenRA
 		public bool LockPreview;
 		public Rectangle Bounds;
 		public MapVisibility Visibility = MapVisibility.Lobby;
-		public string[] Categories = { "Conquest" };
+		public string[] Categories = ["Conquest"];
 
 		public int2 MapSize { get; private set; }
 
 		// Player and actor yaml. Public for access by the map importers and lint checks.
-		public IReadOnlyCollection<MiniYamlNode> PlayerDefinitions = ImmutableArray<MiniYamlNode>.Empty;
-		public IReadOnlyCollection<MiniYamlNode> ActorDefinitions = ImmutableArray<MiniYamlNode>.Empty;
+		public IReadOnlyCollection<MiniYamlNode> PlayerDefinitions = [];
+		public IReadOnlyCollection<MiniYamlNode> ActorDefinitions = [];
 
 		// Custom map yaml. Public for access by the map importers and lint checks
 		public MiniYaml RuleDefinitions;
@@ -211,7 +210,7 @@ namespace OpenRA
 		public MiniYaml MusicDefinitions;
 		public MiniYaml NotificationDefinitions;
 
-		public readonly Dictionary<CPos, TerrainTile> ReplacedInvalidTerrainTiles = new();
+		public readonly Dictionary<CPos, TerrainTile> ReplacedInvalidTerrainTiles = [];
 
 		// Generated data
 		public readonly MapGrid Grid;
@@ -283,7 +282,7 @@ namespace OpenRA
 
 				// Take the SHA1
 				if (streams.Count == 0)
-					return CryptoUtil.SHA1Hash(Array.Empty<byte>());
+					return CryptoUtil.SHA1Hash([]);
 
 				var merged = streams[0];
 				for (var i = 1; i < streams.Count; i++)
@@ -368,8 +367,8 @@ namespace OpenRA
 			if (MapFormat < SupportedMapFormat)
 				throw new InvalidDataException($"Map format {MapFormat} is not supported.\n File: {package.Name}");
 
-			PlayerDefinitions = yaml.NodeWithKeyOrDefault("Players")?.Value.Nodes ?? ImmutableArray<MiniYamlNode>.Empty;
-			ActorDefinitions = yaml.NodeWithKeyOrDefault("Actors")?.Value.Nodes ?? ImmutableArray<MiniYamlNode>.Empty;
+			PlayerDefinitions = yaml.NodeWithKeyOrDefault("Players")?.Value.Nodes ?? [];
+			ActorDefinitions = yaml.NodeWithKeyOrDefault("Actors")?.Value.Nodes ?? [];
 
 			Grid = modData.Manifest.Get<MapGrid>();
 
@@ -516,7 +515,7 @@ namespace OpenRA
 			foreach (var cell in AllCells)
 			{
 				var uv = cell.ToMPos(Grid.Type);
-				cellProjection[uv] = Array.Empty<PPos>();
+				cellProjection[uv] = [];
 				inverseCellProjection[uv] = new List<MPos>(1);
 			}
 
@@ -532,7 +531,7 @@ namespace OpenRA
 			if (Grid.MaximumTerrainHeight == 0)
 			{
 				uv = cell.ToMPos(Grid.Type);
-				cellProjection[cell] = new[] { (PPos)uv };
+				cellProjection[cell] = [(PPos)uv];
 				var inverse = inverseCellProjection[uv];
 				inverse.Clear();
 				inverse.Add(uv);
@@ -607,7 +606,7 @@ namespace OpenRA
 			// Any changes to this function should be reflected when setting projectionSafeBounds.
 			var height = mapHeight[uv];
 			if (height == 0)
-				return new[] { (PPos)uv };
+				return [(PPos)uv];
 
 			// Odd-height ramps get bumped up a level to the next even height layer
 			if ((height & 1) == 1 && Ramp[uv] != 0)
@@ -1044,7 +1043,7 @@ namespace OpenRA
 			return (PPos)CellContaining(projectedPos).ToMPos(Grid.Type);
 		}
 
-		static readonly PPos[] NoProjectedCells = Array.Empty<PPos>();
+		static readonly PPos[] NoProjectedCells = [];
 		public PPos[] ProjectedCellsCovering(MPos uv)
 		{
 			if (!initializedCellProjection)
@@ -1064,7 +1063,7 @@ namespace OpenRA
 				InitializeCellProjection();
 
 			if (!inverseCellProjection.Contains(uv))
-				return new List<MPos>();
+				return [];
 
 			return inverseCellProjection[uv];
 		}

OpenRA.Game/Map/MapCache.cs

@@ -28,7 +28,7 @@ namespace OpenRA
 	{
 		public static readonly MapPreview UnknownMap = new(null, null, MapGridType.Rectangular, null);
 		public IReadOnlyDictionary<IReadOnlyPackage, MapClassification> MapLocations => mapLocations;
-		readonly Dictionary<IReadOnlyPackage, MapClassification> mapLocations = new();
+		readonly Dictionary<IReadOnlyPackage, MapClassification> mapLocations = [];
 		public bool LoadPreviewImages = true;
 
 		readonly Cache<string, MapPreview> previews;
@@ -37,17 +37,17 @@ namespace OpenRA
 		Thread previewLoaderThread;
 		bool previewLoaderThreadShutDown = true;
 		readonly object syncRoot = new();
-		readonly Queue<MapPreview> generateMinimap = new();
+		readonly Queue<MapPreview> generateMinimap = [];
 
-		public HashSet<string> StringPool { get; } = new();
+		public HashSet<string> StringPool { get; } = [];
 
-		readonly List<MapDirectoryTracker> mapDirectoryTrackers = new();
+		readonly List<MapDirectoryTracker> mapDirectoryTrackers = [];
 
 		/// <summary>
 		/// The most recently modified or loaded map at runtime.
 		/// </summary>
 		public string LastModifiedMap { get; private set; } = null;
-		readonly Dictionary<string, string> mapUpdates = new();
+		readonly Dictionary<string, string> mapUpdates = [];
 
 		string lastLoadedLastModifiedMap;
 

OpenRA.Game/Map/MapDirectoryTracker.cs

@@ -24,7 +24,7 @@ namespace OpenRA
 		readonly MapClassification classification;
 
 		enum MapAction { Add, Delete, Update }
-		readonly Dictionary<string, MapAction> mapActionQueue = new();
+		readonly Dictionary<string, MapAction> mapActionQueue = [];
 
 		bool dirty = false;
 

OpenRA.Game/Map/MapGrid.cs

@@ -37,43 +37,43 @@ namespace OpenRA
 			Orientation = orientation;
 			if (type == MapGridType.RectangularIsometric)
 			{
-				Corners = new[]
-				{
+				Corners =
+				[
 					new WVec(0, -724, 724 * (int)tl),
 					new WVec(724, 0, 724 * (int)tr),
 					new WVec(0, 724, 724 * (int)br),
 					new WVec(-724, 0, 724 * (int)bl),
-				};
+				];
 			}
 			else
 			{
-				Corners = new[]
-				{
+				Corners =
+				[
 					new WVec(-512, -512, 512 * (int)tl),
 					new WVec(512, -512, 512 * (int)tr),
 					new WVec(512, 512, 512 * (int)br),
 					new WVec(-512, 512, 512 * (int)bl)
-				};
+				];
 			}
 
 			if (split == RampSplit.X)
 			{
-				Polygons = new[]
-				{
-					new[] { Corners[0], Corners[1], Corners[3] },
-					new[] { Corners[1], Corners[2], Corners[3] }
-				};
+				Polygons =
+				[
+					[Corners[0], Corners[1], Corners[3]],
+					[Corners[1], Corners[2], Corners[3]]
+				];
 			}
 			else if (split == RampSplit.Y)
 			{
-				Polygons = new[]
-				{
-					new[] { Corners[0], Corners[1], Corners[2] },
-					new[] { Corners[0], Corners[2], Corners[3] }
-				};
+				Polygons =
+				[
+					[Corners[0], Corners[1], Corners[2]],
+					[Corners[0], Corners[2], Corners[3]]
+				];
 			}
 			else
-				Polygons = new[] { Corners };
+				Polygons = [Corners];
 
 			// Initial value must be assigned before HeightOffset can be called
 			CenterHeightOffset = 0;
@@ -115,14 +115,14 @@ namespace OpenRA
 		public readonly bool EnableDepthBuffer = false;
 
 		public readonly WVec[] SubCellOffsets =
-		{
+		[
 			new(0, 0, 0),       // full cell - index 0
 			new(-299, -256, 0), // top left - index 1
 			new(256, -256, 0),  // top right - index 2
 			new(0, 0, 0),       // center - index 3
 			new(-299, 256, 0),  // bottom left - index 4
 			new(256, 256, 0),   // bottom right - index 5
-		};
+		];
 
 		public CellRamp[] Ramps { get; }
 
@@ -159,8 +159,9 @@ namespace OpenRA
 			var halfBackward = -halfForward;
 
 			// Slope types are hardcoded following the convention from the TS and RA2 map format
-			Ramps = new[]
-			{
+			Ramps =
+			[
+
 				// Flat
 				new CellRamp(Type, WRot.None),
 
@@ -193,7 +194,7 @@ namespace OpenRA
 				new CellRamp(Type, WRot.None, tl: RampCornerHeight.Half, br: RampCornerHeight.Half, split: RampSplit.Y),
 				new CellRamp(Type, WRot.None, tr: RampCornerHeight.Half, bl: RampCornerHeight.Half, split: RampSplit.X),
 				new CellRamp(Type, WRot.None, tl: RampCornerHeight.Half, br: RampCornerHeight.Half, split: RampSplit.X),
-			};
+			];
 
 			TilesByDistance = CreateTilesByDistance();
 		}
@@ -202,7 +203,7 @@ namespace OpenRA
 		{
 			var ts = new List<CVec>[MaximumTileSearchRange + 1];
 			for (var i = 0; i < MaximumTileSearchRange + 1; i++)
-				ts[i] = new List<CVec>();
+				ts[i] = [];
 
 			for (var j = -MaximumTileSearchRange; j <= MaximumTileSearchRange; j++)
 				for (var i = -MaximumTileSearchRange; i <= MaximumTileSearchRange; i++)

OpenRA.Game/Map/MapPlayers.cs

@@ -24,7 +24,7 @@ namespace OpenRA
 		public readonly Dictionary<string, PlayerReference> Players;
 
 		public MapPlayers()
-			: this(new List<MiniYamlNode>()) { }
+			: this([]) { }
 
 		public MapPlayers(IEnumerable<MiniYamlNode> playerDefinitions)
 		{
@@ -66,7 +66,7 @@ namespace OpenRA
 					Name = $"Multi{index}",
 					Faction = "Random",
 					Playable = true,
-					Enemies = new[] { "Creeps" }
+					Enemies = ["Creeps"]
 				};
 				Players.Add(p.Name, p);
 			}

OpenRA.Game/Map/MapPreview.cs

@@ -51,7 +51,7 @@ namespace OpenRA
 		public readonly string[] categories;
 		public readonly int players;
 		public readonly Rectangle bounds;
-		public readonly short[] spawnpoints = Array.Empty<short>();
+		public readonly short[] spawnpoints = [];
 		public readonly MapGridType map_grid_type;
 		public readonly string minimap;
 		public readonly bool downloading;
@@ -195,7 +195,7 @@ namespace OpenRA
 			}
 		}
 
-		static readonly CPos[] NoSpawns = Array.Empty<CPos>();
+		static readonly CPos[] NoSpawns = [];
 		readonly MapCache cache;
 		readonly ModData modData;
 		IReadOnlyPackage package;
@@ -321,7 +321,7 @@ namespace OpenRA
 			{
 				MapFormat = 0,
 				Title = "Unknown Map",
-				Categories = new[] { "Unknown" },
+				Categories = ["Unknown"],
 				Author = "Unknown Author",
 				TileSet = "unknown",
 				Players = null,
@@ -421,11 +421,11 @@ namespace OpenRA
 					newData.SpawnPoints = spawns.ToArray();
 				}
 				else
-					newData.SpawnPoints = Array.Empty<CPos>();
+					newData.SpawnPoints = [];
 			}
 			catch (Exception)
 			{
-				newData.SpawnPoints = Array.Empty<CPos>();
+				newData.SpawnPoints = [];
 				newData.Status = MapStatus.Unavailable;
 			}
 

OpenRA.Game/Map/PlayerReference.cs

@@ -9,7 +9,6 @@
  */
 #endregion
 
-using System;
 using OpenRA.Primitives;
 
 namespace OpenRA
@@ -54,8 +53,8 @@ namespace OpenRA
 		public bool LockHandicap = false;
 		public int Handicap = 0;
 
-		public string[] Allies = Array.Empty<string>();
-		public string[] Enemies = Array.Empty<string>();
+		public string[] Allies = [];
+		public string[] Enemies = [];
 
 		public PlayerReference() { }
 		public PlayerReference(MiniYaml my) { FieldLoader.Load(this, my); }

OpenRA.Game/Map/TerrainInfo.cs

@@ -60,7 +60,7 @@ namespace OpenRA
 	{
 		public readonly string Type;
 		public readonly BitSet<TargetableType> TargetTypes;
-		public readonly HashSet<string> AcceptsSmudgeType = new();
+		public readonly HashSet<string> AcceptsSmudgeType = [];
 		public readonly Color Color;
 		public readonly bool RestrictPlayerColor = false;
 

OpenRA.Game/MiniYaml.cs

@@ -99,7 +99,7 @@ namespace OpenRA
 		}
 
 		public MiniYamlNode(string k, string v, string c = null)
-			: this(k, new MiniYaml(v, Enumerable.Empty<MiniYamlNode>()), c) { }
+			: this(k, new MiniYaml(v, []), c) { }
 
 		public MiniYamlNode(string k, string v, IEnumerable<MiniYamlNode> n)
 			: this(k, new MiniYaml(v, n), null) { }
@@ -115,7 +115,7 @@ namespace OpenRA
 		const int SpacesPerLevel = 4;
 		static readonly Func<string, string> StringIdentity = s => s;
 		static readonly Func<MiniYaml, MiniYaml> MiniYamlIdentity = my => my;
-		static readonly Dictionary<string, MiniYamlNode> ConflictScratch = new();
+		static readonly Dictionary<string, MiniYamlNode> ConflictScratch = [];
 
 		public readonly string Value;
 		public readonly ImmutableArray<MiniYamlNode> Nodes;
@@ -196,12 +196,12 @@ namespace OpenRA
 		}
 
 		public MiniYaml(string value)
-			: this(value, Enumerable.Empty<MiniYamlNode>()) { }
+			: this(value, []) { }
 
 		public MiniYaml(string value, IEnumerable<MiniYamlNode> nodes)
 		{
 			Value = value;
-			Nodes = ImmutableArray.CreateRange(nodes);
+			Nodes = nodes.ToImmutableArray();
 		}
 
 		static List<MiniYamlNode> FromLines(IEnumerable<ReadOnlyMemory<char>> lines, string name, bool discardCommentsAndWhitespace, HashSet<string> stringPool)
@@ -210,7 +210,7 @@ namespace OpenRA
 			// 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>();
+			stringPool ??= [];
 
 			var result = new List<List<MiniYamlNode>>
 			{
@@ -352,7 +352,7 @@ namespace OpenRA
 			{
 				var lastLevel = parsedLines[^1].Level;
 				while (lastLevel >= result.Count)
-					result.Add(new List<MiniYamlNode>());
+					result.Add([]);
 
 				while (parsedLines.Count > 0 && parsedLines[^1].Level >= level)
 				{
@@ -393,14 +393,14 @@ namespace OpenRA
 
 		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()), name, discardCommentsAndWhitespace, stringPool);
+			return FromLines(text.Split(["\r\n", "\n"], StringSplitOptions.None).Select(s => s.AsMemory()), name, discardCommentsAndWhitespace, stringPool);
 		}
 
 		public static List<MiniYamlNode> Merge(IEnumerable<IReadOnlyCollection<MiniYamlNode>> sources)
 		{
 			var sourcesList = sources.ToList();
 			if (sourcesList.Count == 0)
-				return new List<MiniYamlNode>();
+				return [];
 
 			var tree = sourcesList
 				.Where(s => s != null)
@@ -696,7 +696,7 @@ namespace OpenRA
 		public MiniYamlBuilder(string value, List<MiniYamlNode> nodes)
 		{
 			Value = value;
-			Nodes = nodes == null ? new List<MiniYamlNodeBuilder>() : nodes.ConvertAll(x => new MiniYamlNodeBuilder(x));
+			Nodes = nodes == null ? [] : nodes.ConvertAll(x => new MiniYamlNodeBuilder(x));
 		}
 
 		public MiniYaml Build()

OpenRA.Game/ModData.cs

@@ -49,7 +49,7 @@ namespace OpenRA
 
 		public ModData(Manifest mod, InstalledMods mods, bool useLoadScreen = false)
 		{
-			Languages = Array.Empty<string>();
+			Languages = [];
 
 			// Take a local copy of the manifest
 			Manifest = new Manifest(mod.Id, mod.Package);
@@ -82,19 +82,19 @@ namespace OpenRA
 
 			var terrainFormat = Manifest.Get<TerrainFormat>();
 			var terrainLoader = ObjectCreator.FindType(terrainFormat.Type + "Loader");
-			var terrainCtor = terrainLoader?.GetConstructor(new[] { typeof(ModData) });
+			var terrainCtor = terrainLoader?.GetConstructor([typeof(ModData)]);
 			if (terrainLoader == null || !terrainLoader.GetInterfaces().Contains(typeof(ITerrainLoader)) || terrainCtor == null)
 				throw new InvalidOperationException($"Unable to find a terrain loader for type '{terrainFormat.Type}'.");
 
-			TerrainLoader = (ITerrainLoader)terrainCtor.Invoke(new[] { this });
+			TerrainLoader = (ITerrainLoader)terrainCtor.Invoke([this]);
 
 			var sequenceFormat = Manifest.Get<SpriteSequenceFormat>();
 			var sequenceLoader = ObjectCreator.FindType(sequenceFormat.Type + "Loader");
-			var sequenceCtor = sequenceLoader?.GetConstructor(new[] { typeof(ModData) });
+			var sequenceCtor = sequenceLoader?.GetConstructor([typeof(ModData)]);
 			if (sequenceLoader == null || !sequenceLoader.GetInterfaces().Contains(typeof(ISpriteSequenceLoader)) || sequenceCtor == null)
 				throw new InvalidOperationException($"Unable to find a sequence loader for type '{sequenceFormat.Type}'.");
 
-			SpriteSequenceLoader = (ISpriteSequenceLoader)sequenceCtor.Invoke(new[] { this });
+			SpriteSequenceLoader = (ISpriteSequenceLoader)sequenceCtor.Invoke([this]);
 
 			Hotkeys = new HotkeyManager(ModFiles, Game.Settings.Keys, Manifest);
 

OpenRA.Game/Network/Connection.cs

@@ -42,9 +42,9 @@ namespace OpenRA.Network
 	public sealed class EchoConnection : IConnection
 	{
 		const int LocalClientId = 1;
-		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> sync = new();
-		readonly Queue<(int Frame, OrderPacket Orders)> orders = new();
-		readonly Queue<OrderPacket> immediateOrders = new();
+		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> sync = [];
+		readonly Queue<(int Frame, OrderPacket Orders)> orders = [];
+		readonly Queue<OrderPacket> immediateOrders = [];
 		bool disposed;
 
 		int IConnection.LocalClientId => LocalClientId;
@@ -52,7 +52,7 @@ namespace OpenRA.Network
 		void IConnection.StartGame()
 		{
 			// Inject an empty frame to fill the gap we are making by projecting forward orders
-			orders.Enqueue((0, new OrderPacket(Array.Empty<Order>())));
+			orders.Enqueue((0, new OrderPacket([])));
 		}
 
 		void IConnection.Send(int frame, IEnumerable<Order> o)
@@ -100,12 +100,12 @@ namespace OpenRA.Network
 	{
 		public readonly ConnectionTarget Target;
 		internal ReplayRecorder Recorder { get; private set; }
-		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> sentSync = new();
-		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> queuedSyncPackets = new();
+		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> sentSync = [];
+		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> queuedSyncPackets = [];
 
-		readonly Queue<(int Frame, OrderPacket Orders)> sentOrders = new();
-		readonly Queue<OrderPacket> sentImmediateOrders = new();
-		readonly ConcurrentQueue<(int FromClient, byte[] Data)> receivedPackets = new();
+		readonly Queue<(int Frame, OrderPacket Orders)> sentOrders = [];
+		readonly Queue<OrderPacket> sentImmediateOrders = [];
+		readonly ConcurrentQueue<(int FromClient, byte[] Data)> receivedPackets = [];
 		TcpClient tcp;
 		volatile ConnectionState connectionState = ConnectionState.Connecting;
 		volatile int clientId;

OpenRA.Game/Network/ConnectionTarget.cs

@@ -22,12 +22,12 @@ namespace OpenRA.Network
 
 		public ConnectionTarget()
 		{
-			endpoints = new[] { new DnsEndPoint("invalid", 0) };
+			endpoints = [new DnsEndPoint("invalid", 0)];
 		}
 
 		public ConnectionTarget(string host, int port)
 		{
-			endpoints = new[] { new DnsEndPoint(host, port) };
+			endpoints = [new DnsEndPoint(host, port)];
 		}
 
 		public ConnectionTarget(IEnumerable<DnsEndPoint> endpoints)
@@ -48,7 +48,7 @@ namespace OpenRA.Network
 				}
 				catch (Exception)
 				{
-					return Enumerable.Empty<IPEndPoint>();
+					return [];
 				}
 			}).ToList();
 		}

OpenRA.Game/Network/GameSave.cs

@@ -86,22 +86,22 @@ namespace OpenRA.Network
 		// Loaded from file and updated during gameplay
 		public int LastOrdersFrame { get; private set; }
 		public int LastSyncFrame { get; private set; }
-		byte[] lastSyncPacket = Array.Empty<byte>();
+		byte[] lastSyncPacket = [];
 
 		// Loaded from file or set on game start
 		public Session.Global GlobalSettings { get; private set; }
 		public Dictionary<string, Session.Slot> Slots { get; private set; }
 		public Dictionary<string, SlotClient> SlotClients { get; private set; }
-		public Dictionary<int, MiniYaml> TraitData = new();
+		public Dictionary<int, MiniYaml> TraitData = [];
 
 		// Set on game start
-		int[] clientsBySlotIndex = Array.Empty<int>();
+		int[] clientsBySlotIndex = [];
 		int firstBotSlotIndex = -1;
 
 		public GameSave()
 		{
 			LastOrdersFrame = -1;
-			Slots = new Dictionary<string, Session.Slot>();
+			Slots = [];
 		}
 
 		public GameSave(string filepath)
@@ -126,7 +126,7 @@ namespace OpenRA.Network
 				GlobalSettings = Session.Global.Deserialize(globalSettings[0].Value);
 
 				var slots = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:slots");
-				Slots = new Dictionary<string, Session.Slot>();
+				Slots = [];
 				foreach (var s in slots)
 				{
 					var slot = Session.Slot.Deserialize(s.Value);
@@ -134,7 +134,7 @@ namespace OpenRA.Network
 				}
 
 				var slotClients = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:slotClients");
-				SlotClients = new Dictionary<string, SlotClient>();
+				SlotClients = [];
 				foreach (var s in slotClients)
 				{
 					var slotClient = SlotClient.Deserialize(s.Value);
@@ -166,8 +166,8 @@ namespace OpenRA.Network
 
 			// Perform a deep clone by round-tripping the data
 			GlobalSettings = Session.Global.Deserialize(lobbyInfo.GlobalSettings.Serialize().Value);
-			Slots = new Dictionary<string, Session.Slot>();
-			SlotClients = new Dictionary<string, SlotClient>();
+			Slots = [];
+			SlotClients = [];
 			foreach (var s in lobbyInfo.Slots)
 			{
 				Slots[s.Key] = Session.Slot.Deserialize(s.Value.Serialize().Value);

OpenRA.Game/Network/GameServer.cs

@@ -48,7 +48,8 @@ namespace OpenRA.Network
 	public class GameServer
 	{
 		static readonly string[] SerializeFields =
-		{
+		[
+
 			// Server information
 			"Name", "Address",
 
@@ -57,7 +58,7 @@ namespace OpenRA.Network
 
 			// Current server state
 			"Map", "State", "MaxPlayers", "Protected", "Authentication", "DisabledSpawnPoints"
-		};
+		];
 
 		public const int ProtocolVersion = 2;
 
@@ -133,7 +134,7 @@ namespace OpenRA.Network
 		public readonly GameClient[] Clients;
 
 		/// <summary>The list of spawnpoints that are disabled for this game.</summary>
-		public readonly int[] DisabledSpawnPoints = Array.Empty<int>();
+		public readonly int[] DisabledSpawnPoints = [];
 
 		public string ModLabel => $"{ModTitle} ({Version})";
 
@@ -228,7 +229,7 @@ namespace OpenRA.Network
 			Protected = !string.IsNullOrEmpty(server.Settings.Password);
 			Authentication = server.Settings.RequireAuthentication || server.Settings.ProfileIDWhitelist.Length > 0;
 			Clients = server.LobbyInfo.Clients.Select(c => new GameClient(c)).ToArray();
-			DisabledSpawnPoints = server.LobbyInfo.DisabledSpawnPoints?.ToArray() ?? Array.Empty<int>();
+			DisabledSpawnPoints = server.LobbyInfo.DisabledSpawnPoints?.ToArray() ?? [];
 		}
 
 		public string ToPOSTData(bool lanGame)

OpenRA.Game/Network/OrderIO.cs

@@ -78,7 +78,7 @@ namespace OpenRA.Network
 
 	public static class OrderIO
 	{
-		static readonly OrderPacket NoOrders = new(Array.Empty<Order>());
+		static readonly OrderPacket NoOrders = new([]);
 
 		public static byte[] SerializeSync((int Frame, int SyncHash, ulong DefeatState) data)
 		{

OpenRA.Game/Network/OrderManager.cs

@@ -26,8 +26,8 @@ namespace OpenRA.Network
 		const string DesyncCompareLogs = "notification-desync-compare-logs";
 
 		readonly SyncReport syncReport;
-		readonly Dictionary<int, Queue<(int Frame, OrderPacket Orders)>> pendingOrders = new();
-		readonly Dictionary<int, (int SyncHash, ulong DefeatState)> syncForFrame = new();
+		readonly Dictionary<int, Queue<(int Frame, OrderPacket Orders)>> pendingOrders = [];
+		readonly Dictionary<int, (int SyncHash, ulong DefeatState)> syncForFrame = [];
 
 		public Session LobbyInfo = new();
 
@@ -53,11 +53,11 @@ namespace OpenRA.Network
 		internal int GameSaveLastFrame = -1;
 		internal int GameSaveLastSyncFrame = -1;
 
-		readonly List<Order> localOrders = new();
-		readonly List<Order> localImmediateOrders = new();
+		readonly List<Order> localOrders = [];
+		readonly List<Order> localImmediateOrders = [];
 
-		readonly List<ClientOrder> processClientOrders = new();
-		readonly List<int> processClientsToRemove = new();
+		readonly List<ClientOrder> processClientOrders = [];
+		readonly List<int> processClientsToRemove = [];
 
 		bool disposed;
 		bool generateSyncReport = false;

OpenRA.Game/Network/ReplayConnection.cs

@@ -24,8 +24,8 @@ namespace OpenRA.Network
 			public (int ClientId, byte[] Packet)[] Packets;
 		}
 
-		readonly Queue<Chunk> chunks = new();
-		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> sync = new();
+		readonly Queue<Chunk> chunks = [];
+		readonly Queue<(int Frame, int SyncHash, ulong DefeatState)> sync = [];
 		readonly int orderLatency;
 
 		public readonly int TickCount;

OpenRA.Game/Network/Session.cs

@@ -20,12 +20,12 @@ namespace OpenRA.Network
 {
 	public class Session
 	{
-		public List<Client> Clients = new();
+		public List<Client> Clients = [];
 
 		// Keyed by the PlayerReference id that the slot corresponds to
-		public Dictionary<string, Slot> Slots = new();
+		public Dictionary<string, Slot> Slots = [];
 
-		public HashSet<int> DisabledSpawnPoints = new();
+		public HashSet<int> DisabledSpawnPoints = [];
 
 		public Global GlobalSettings = new();
 
@@ -221,7 +221,7 @@ namespace OpenRA.Network
 			public int NetFrameInterval = 3;
 
 			[FieldLoader.Ignore]
-			public Dictionary<string, LobbyOptionState> LobbyOptions = new();
+			public Dictionary<string, LobbyOptionState> LobbyOptions = [];
 
 			public static Global Deserialize(MiniYaml data)
 			{
@@ -240,7 +240,7 @@ namespace OpenRA.Network
 				var data = new MiniYamlNode("GlobalSettings", FieldSaver.Save(this));
 				var options = LobbyOptions.Select(kv => new MiniYamlNode(kv.Key, FieldSaver.Save(kv.Value)));
 				data = data.WithValue(data.Value.WithNodesAppended(
-					new[] { new MiniYamlNode("Options", new MiniYaml(null, options)) }));
+					[new MiniYamlNode("Options", new MiniYaml(null, options))]));
 				return data;
 			}
 

OpenRA.Game/Network/SyncReport.cs

@@ -166,9 +166,9 @@ namespace OpenRA.Network
 			public int Frame;
 			public int SyncedRandom;
 			public int TotalCount;
-			public readonly List<TraitReport> Traits = new();
-			public readonly List<EffectReport> Effects = new();
-			public readonly List<OrderManager.ClientOrder> Orders = new();
+			public readonly List<TraitReport> Traits = [];
+			public readonly List<EffectReport> Effects = [];
+			public readonly List<OrderManager.ClientOrder> Orders = [];
 		}
 
 		struct TraitReport
@@ -238,11 +238,11 @@ namespace OpenRA.Network
 						// PERF: If the member is a Boolean, we can also avoid the allocation caused by boxing it.
 						// Instead, we can just return the resulting strings directly.
 						var getBoolString = Expression.Condition(getMember, TrueString, FalseString);
-						return Expression.Lambda<Func<ISync, string>>(getBoolString, name, new[] { SyncParam }).Compile();
+						return Expression.Lambda<Func<ISync, string>>(getBoolString, name, [SyncParam]).Compile();
 					}
 
 					var boxedCopy = Expression.Convert(getMember, typeof(object));
-					return Expression.Lambda<Func<ISync, object>>(boxedCopy, name, new[] { SyncParam }).Compile();
+					return Expression.Lambda<Func<ISync, object>>(boxedCopy, name, [SyncParam]).Compile();
 				}
 
 				// For reference types, we have to call ToString right away to get a snapshot of the value. We cannot
@@ -266,13 +266,13 @@ namespace OpenRA.Network
 					// (ISync sync) => { var foo = ((TSync)sync).Foo; return foo == null ? null : foo.ToString(); }
 					var memberVariable = Expression.Variable(memberType, getMember.Member.Name);
 					var assignMemberVariable = Expression.Assign(memberVariable, getMember);
-					var member = Expression.Block(new[] { memberVariable }, assignMemberVariable);
+					var member = Expression.Block([memberVariable], assignMemberVariable);
 					getString = Expression.Call(member, toString);
 					var nullMember = Expression.Constant(null, memberType);
 					getString = Expression.Condition(Expression.Equal(member, nullMember), NullString, getString);
 				}
 
-				return Expression.Lambda<Func<ISync, string>>(getString, name, new[] { SyncParam }).Compile();
+				return Expression.Lambda<Func<ISync, string>>(getString, name, [SyncParam]).Compile();
 			}
 		}
 

OpenRA.Game/ObjectCreator.cs

@@ -22,7 +22,7 @@ namespace OpenRA
 	{
 		// .NET does not support unloading assemblies, so mod libraries will leak across mod changes.
 		// This tracks the assemblies that have been loaded since game start so that we don't load multiple copies
-		static readonly Dictionary<string, Assembly> ResolvedAssemblies = new();
+		static readonly Dictionary<string, Assembly> ResolvedAssemblies = [];
 
 		readonly Cache<string, Type> typeCache;
 		readonly Cache<Type, ConstructorInfo> ctorCache;
@@ -77,7 +77,7 @@ namespace OpenRA
 
 		public T CreateObject<T>(string className)
 		{
-			return CreateObject<T>(className, new Dictionary<string, object>());
+			return CreateObject<T>(className, []);
 		}
 
 		public T CreateObject<T>(string className, Dictionary<string, object> args)
@@ -119,7 +119,7 @@ namespace OpenRA
 
 		public object CreateBasic(Type type)
 		{
-			return type.GetConstructor(Array.Empty<Type>()).Invoke(Array.Empty<object>());
+			return type.GetConstructor([]).Invoke([]);
 		}
 
 		public object CreateUsingArgs(ConstructorInfo ctor, Dictionary<string, object> args)

OpenRA.Game/Player.cs

@@ -207,7 +207,7 @@ namespace OpenRA
 			// Therefore assign the uninitialized actor and run the Created callbacks
 			// by calling Initialize ourselves.
 			var playerActorType = world.Type == WorldType.Editor ? SystemActors.EditorPlayer : SystemActors.Player;
-			PlayerActor = new Actor(world, playerActorType.ToString(), new TypeDictionary { new OwnerInit(this) });
+			PlayerActor = new Actor(world, playerActorType.ToString(), [new OwnerInit(this)]);
 			PlayerActor.Initialize(true);
 
 			Shroud = PlayerActor.Trait<Shroud>();

OpenRA.Game/Primitives/ActionQueue.cs

@@ -19,7 +19,7 @@ namespace OpenRA.Primitives
 	/// </summary>
 	public class ActionQueue
 	{
-		readonly List<DelayedAction> actions = new();
+		readonly List<DelayedAction> actions = [];
 
 		public void Add(Action a, long desiredTime)
 		{

OpenRA.Game/Primitives/Color.cs

@@ -219,9 +219,9 @@ namespace OpenRA.Primitives
 		public override string ToString()
 		{
 			if (A == 255)
-				return CryptoUtil.ToHex(stackalloc byte[3] { R, G, B });
+				return CryptoUtil.ToHex([R, G, B]);
 
-			return CryptoUtil.ToHex(stackalloc byte[4] { R, G, B, A });
+			return CryptoUtil.ToHex([R, G, B, A]);
 		}
 
 		public static Color Transparent => FromArgb(0x00FFFFFF);

OpenRA.Game/Primitives/ObservableList.cs

@@ -33,7 +33,7 @@ namespace OpenRA.Primitives
 
 		public ObservableList()
 		{
-			innerList = new List<T>();
+			innerList = [];
 		}
 
 		public virtual void Add(T item)

OpenRA.Game/Primitives/Polygon.cs

@@ -25,7 +25,7 @@ namespace OpenRA.Primitives
 		public Polygon(Rectangle bounds)
 		{
 			BoundingRect = bounds;
-			Vertices = new[] { bounds.TopLeft, bounds.BottomLeft, bounds.BottomRight, bounds.TopRight };
+			Vertices = [bounds.TopLeft, bounds.BottomLeft, bounds.BottomRight, bounds.TopRight];
 			isRectangle = true;
 		}
 

OpenRA.Game/Primitives/SpatiallyPartitioned.cs

@@ -23,7 +23,7 @@ namespace OpenRA.Primitives
 
 		readonly int rows, cols, binSize;
 		readonly Dictionary<T, Rectangle>[] itemBoundsBins;
-		readonly Dictionary<T, Rectangle> itemBounds = new();
+		readonly Dictionary<T, Rectangle> itemBounds = [];
 
 		public SpatiallyPartitioned(int width, int height, int binSize)
 		{

OpenRA.Game/Primitives/TypeDictionary.cs

@@ -20,7 +20,7 @@ namespace OpenRA.Primitives
 		static readonly Func<Type, ITypeContainer> CreateTypeContainer = t =>
 			(ITypeContainer)typeof(TypeContainer<>).MakeGenericType(t).GetConstructor(Type.EmptyTypes).Invoke(null);
 
-		readonly Dictionary<Type, ITypeContainer> data = new();
+		readonly Dictionary<Type, ITypeContainer> data = [];
 
 		ITypeContainer InnerGet(Type t)
 		{
@@ -81,7 +81,7 @@ namespace OpenRA.Primitives
 		{
 			if (data.TryGetValue(typeof(T), out var container))
 				return ((TypeContainer<T>)container).Objects;
-			return Array.Empty<T>();
+			return [];
 		}
 
 		public void Remove<T>(T val)
@@ -131,7 +131,7 @@ namespace OpenRA.Primitives
 
 		sealed class TypeContainer<T> : ITypeContainer
 		{
-			public List<T> Objects { get; } = new List<T>();
+			public List<T> Objects { get; } = [];
 
 			public int Count => Objects.Count;
 

OpenRA.Game/Renderer.cs

@@ -27,7 +27,7 @@ namespace OpenRA
 		public SpriteRenderer WorldSpriteRenderer { get; }
 		public RgbaSpriteRenderer WorldRgbaSpriteRenderer { get; }
 		public RgbaColorRenderer WorldRgbaColorRenderer { get; }
-		public IRenderer[] WorldRenderers = Array.Empty<IRenderer>();
+		public IRenderer[] WorldRenderers = [];
 		public RgbaColorRenderer RgbaColorRenderer { get; }
 		public SpriteRenderer SpriteRenderer { get; }
 		public RgbaSpriteRenderer RgbaSpriteRenderer { get; }
@@ -46,7 +46,7 @@ namespace OpenRA
 
 		readonly IVertexBuffer<Vertex> tempVertexBuffer;
 		readonly IIndexBuffer quadIndexBuffer;
-		readonly Stack<Rectangle> scissorState = new();
+		readonly Stack<Rectangle> scissorState = [];
 		readonly ITexture worldBufferSnapshot;
 
 		IFrameBuffer screenBuffer;

OpenRA.Game/Scripting/ScriptActorInterface.cs

@@ -43,7 +43,7 @@ namespace OpenRA.Scripting
 			if (actor.Disposed)
 				commandClasses = commandClasses.Where(c => c.HasAttribute<ExposedForDestroyedActors>()).ToArray();
 
-			Bind(CreateObjects(commandClasses, new object[] { Context, actor }));
+			Bind(CreateObjects(commandClasses, [Context, actor]));
 		}
 
 		public void OnActorDestroyed()

OpenRA.Game/Scripting/ScriptContext.cs

@@ -103,7 +103,7 @@ namespace OpenRA.Scripting
 				throw new InvalidOperationException($"[ScriptGlobal] attribute not found for global table '{type}'");
 
 			Name = names[0].Name;
-			Bind(new[] { this });
+			Bind([this]);
 		}
 
 		protected IEnumerable<T> FilteredObjects<T>(IEnumerable<T> objects, LuaFunction filter)
@@ -220,7 +220,7 @@ namespace OpenRA.Scripting
 				if (ctor == null)
 					throw new InvalidOperationException($"{b.Name} must define a constructor that takes a {nameof(ScriptContext)} context parameter");
 
-				var binding = (ScriptGlobal)ctor.Invoke(new[] { this });
+				var binding = (ScriptGlobal)ctor.Invoke([this]);
 				using (var obj = binding.ToLuaValue(this))
 					runtime.Globals.Add(binding.Name, obj);
 			}
@@ -341,7 +341,7 @@ namespace OpenRA.Scripting
 			return outer.SelectMany(i => i.GetGenericArguments());
 		}
 
-		static readonly object[] NoArguments = Array.Empty<object>();
+		static readonly object[] NoArguments = [];
 		Type[] FilterActorCommands(ActorInfo ai)
 		{
 			return FilterCommands(ai, knownActorCommands);

OpenRA.Game/Scripting/ScriptObjectWrapper.cs

@@ -22,7 +22,7 @@ namespace OpenRA.Scripting
 		protected abstract string MemberNotFoundError(string memberName);
 
 		protected readonly ScriptContext Context;
-		readonly Dictionary<string, ScriptMemberWrapper> members = new();
+		readonly Dictionary<string, ScriptMemberWrapper> members = [];
 
 		protected ScriptObjectWrapper(ScriptContext context)
 		{

OpenRA.Game/Scripting/ScriptPlayerInterface.cs

@@ -24,7 +24,7 @@ namespace OpenRA.Scripting
 			: base(context)
 		{
 			this.player = player;
-			Bind(CreateObjects(context.PlayerCommands, new object[] { context, player }));
+			Bind(CreateObjects(context.PlayerCommands, [context, player]));
 		}
 	}
 }

OpenRA.Game/SelectableExts.cs

@@ -87,7 +87,7 @@ namespace OpenRA.Traits
 			return info.SelectionPriority(modifiers) - (long)pixelDistance << 16;
 		}
 
-		static readonly Actor[] NoActors = Array.Empty<Actor>();
+		static readonly Actor[] NoActors = [];
 
 		public static IEnumerable<Actor> SubsetWithHighestSelectionPriority(this IEnumerable<Actor> actors, Modifiers modifiers)
 		{

OpenRA.Game/Server/Connection.cs

@@ -41,8 +41,8 @@ namespace OpenRA.Server
 
 		long lastReceivedTime = 0;
 
-		readonly BlockingCollection<byte[]> sendQueue = new();
-		readonly Queue<int> pingHistory = new();
+		readonly BlockingCollection<byte[]> sendQueue = [];
+		readonly Queue<int> pingHistory = [];
 
 		public Connection(Server server, Socket socket, string authToken)
 		{

OpenRA.Game/Server/Exts.cs

@@ -18,7 +18,7 @@ namespace OpenRA.Server
 	{
 		public static IEnumerable<T> Except<T>(this IEnumerable<T> ts, T t)
 		{
-			return ts.Except(new[] { t });
+			return ts.Except([t]);
 		}
 	}
 }

OpenRA.Game/Server/MapStatusCache.cs

@@ -20,7 +20,7 @@ namespace OpenRA.Server
 
 	public class MapStatusCache
 	{
-		readonly Dictionary<MapPreview, Session.MapStatus> cache = new();
+		readonly Dictionary<MapPreview, Session.MapStatus> cache = [];
 		readonly Action<string, Session.MapStatus> onStatusChanged;
 		readonly bool enableRemoteLinting;
 		readonly ModData modData;

OpenRA.Game/Server/OrderBuffer.cs

@@ -31,8 +31,8 @@ namespace OpenRA.Server
 		Stopwatch gameTimer;
 		long nextUpdate = 0;
 
-		readonly ConcurrentDictionary<int, long> timestamps = new();
-		readonly ConcurrentDictionary<int, Queue<long>> deltas = new();
+		readonly ConcurrentDictionary<int, long> timestamps = [];
+		readonly ConcurrentDictionary<int, Queue<long>> deltas = [];
 
 		int timestep;
 		int ticksPerInterval;

OpenRA.Game/Server/PlayerMessageTracker.cs

@@ -19,7 +19,7 @@ namespace OpenRA.Server
 		[FluentReference("remaining")]
 		const string ChatTemporaryDisabled = "notification-chat-temp-disabled";
 
-		readonly Dictionary<int, List<long>> messageTracker = new();
+		readonly Dictionary<int, List<long>> messageTracker = [];
 		readonly Server server;
 		readonly Action<Connection, int, int, byte[]> dispatchOrdersToClient;
 		readonly Action<Connection, string, object[]> sendFluentMessageTo;
@@ -42,7 +42,7 @@ namespace OpenRA.Server
 		public bool IsPlayerAtFloodLimit(Connection conn)
 		{
 			if (!messageTracker.ContainsKey(conn.PlayerIndex))
-				messageTracker.Add(conn.PlayerIndex, new List<long>());
+				messageTracker.Add(conn.PlayerIndex, []);
 
 			var isAdmin = server.GetClient(conn)?.IsAdmin ?? false;
 			var settings = server.Settings;
@@ -56,7 +56,7 @@ namespace OpenRA.Server
 			if (!isAdmin && time < settings.FloodLimitJoinCooldown)
 			{
 				var remaining = CalculateRemaining(settings.FloodLimitJoinCooldown);
-				sendFluentMessageTo(conn, ChatTemporaryDisabled, new object[] { "remaining", remaining });
+				sendFluentMessageTo(conn, ChatTemporaryDisabled, ["remaining", remaining]);
 				return true;
 			}
 
@@ -64,7 +64,7 @@ namespace OpenRA.Server
 			if (tracker.Count >= settings.FloodLimitMessageCount)
 			{
 				var remaining = CalculateRemaining(tracker[0] + settings.FloodLimitInterval);
-				sendFluentMessageTo(conn, ChatTemporaryDisabled, new object[] { "remaining", remaining });
+				sendFluentMessageTo(conn, ChatTemporaryDisabled, ["remaining", remaining]);
 				return true;
 			}
 

OpenRA.Game/Server/Server.cs

@@ -120,12 +120,12 @@ namespace OpenRA.Server
 		public readonly ServerType Type;
 		public bool IsMultiplayer => Type == ServerType.Dedicated || Type == ServerType.Multiplayer;
 
-		public readonly List<Connection> Conns = new();
+		public readonly List<Connection> Conns = [];
 
 		public Session LobbyInfo;
 		public ServerSettings Settings;
 		public ModData ModData;
-		public List<string> TempBans = new();
+		public List<string> TempBans = [];
 
 		// Managed by LobbyCommands
 		public MapPreview Map;
@@ -137,19 +137,19 @@ namespace OpenRA.Server
 		public int OrderLatency = 1;
 
 		readonly int randomSeed;
-		readonly List<TcpListener> listeners = new();
-		readonly TypeDictionary serverTraits = new();
+		readonly List<TcpListener> listeners = [];
+		readonly TypeDictionary serverTraits = [];
 		readonly PlayerDatabase playerDatabase;
 
 		OrderBuffer orderBuffer;
 
 		volatile ServerState internalState = ServerState.WaitingPlayers;
 
-		readonly BlockingCollection<IServerEvent> events = new();
+		readonly BlockingCollection<IServerEvent> events = [];
 
 		ReplayRecorder recorder;
 		GameInformation gameInfo;
-		readonly List<GameInformation.Player> worldPlayers = new();
+		readonly List<GameInformation.Player> worldPlayers = [];
 		readonly Stopwatch pingUpdated = Stopwatch.StartNew();
 
 		public readonly VoteKickTracker VoteKickTracker;
@@ -802,7 +802,7 @@ namespace OpenRA.Server
 			recorder = null;
 		}
 
-		readonly Dictionary<int, byte[]> syncForFrame = new();
+		readonly Dictionary<int, byte[]> syncForFrame = [];
 		int lastDefeatStateFrame;
 		ulong lastDefeatState;
 
@@ -998,7 +998,7 @@ namespace OpenRA.Server
 						if (!InterpretCommand(o.TargetString, conn))
 						{
 							Log.Write("server", $"Unknown server command: {o.TargetString}");
-							SendFluentMessageTo(conn, UnknownServerCommand, new object[] { "command", o.TargetString });
+							SendFluentMessageTo(conn, UnknownServerCommand, ["command", o.TargetString]);
 						}
 
 						break;
@@ -1401,12 +1401,12 @@ namespace OpenRA.Server
 					for (var i = 0; i < OrderLatency; i++)
 					{
 						from.LastOrdersFrame = firstFrame + i;
-						var frameData = CreateFrame(from.PlayerIndex, from.LastOrdersFrame, Array.Empty<byte>());
+						var frameData = CreateFrame(from.PlayerIndex, from.LastOrdersFrame, []);
 						foreach (var to in conns)
 							DispatchFrameToClient(to, from.PlayerIndex, frameData);
 
-						RecordOrder(from.LastOrdersFrame, Array.Empty<byte>(), from.PlayerIndex);
-						GameSave?.DispatchOrders(from, from.LastOrdersFrame, Array.Empty<byte>());
+						RecordOrder(from.LastOrdersFrame, [], from.PlayerIndex);
+						GameSave?.DispatchOrders(from, from.LastOrdersFrame, []);
 					}
 				}
 			}

OpenRA.Game/Server/VoteKickTracker.cs

@@ -35,8 +35,8 @@ namespace OpenRA.Server
 		[FluentReference("kickee")]
 		const string VoteKickEnded = "notification-vote-kick-ended";
 
-		readonly Dictionary<int, bool> voteTracker = new();
-		readonly Dictionary<Session.Client, long> failedVoteKickers = new();
+		readonly Dictionary<int, bool> voteTracker = [];
+		readonly Dictionary<Session.Client, long> failedVoteKickers = [];
 		readonly Server server;
 
 		Stopwatch voteKickTimer;
@@ -107,7 +107,7 @@ namespace OpenRA.Server
 				if (!kickee.IsObserver && !server.HasClientWonOrLost(kickee))
 				{
 					// Vote kick cannot be the sole deciding factor for a game.
-					server.SendFluentMessageTo(conn, InsufficientVotes, new object[] { "kickee", kickee.Name });
+					server.SendFluentMessageTo(conn, InsufficientVotes, ["kickee", kickee.Name]);
 					EndKickVote();
 					return false;
 				}

OpenRA.Game/Settings.cs

@@ -66,16 +66,16 @@ namespace OpenRA
 		public string Map = null;
 
 		[Desc("Takes a comma separated list of IP addresses that are not allowed to join.")]
-		public string[] Ban = Array.Empty<string>();
+		public string[] Ban = [];
 
 		[Desc("For dedicated servers only, allow anonymous clients to join.")]
 		public bool RequireAuthentication = false;
 
 		[Desc("For dedicated servers only, if non-empty, only allow authenticated players with these profile IDs to join.")]
-		public int[] ProfileIDWhitelist = Array.Empty<int>();
+		public int[] ProfileIDWhitelist = [];
 
 		[Desc("For dedicated servers only, if non-empty, always reject players with these user IDs from joining.")]
-		public int[] ProfileIDBlacklist = Array.Empty<int>();
+		public int[] ProfileIDBlacklist = [];
 
 		[Desc("For dedicated servers only, controls whether a game can be started with just one human player in the lobby.")]
 		public bool EnableSingleplayer = false;
@@ -102,7 +102,7 @@ namespace OpenRA
 		public bool EnableLintChecks = true;
 
 		[Desc("For dedicated servers only, a comma separated list of map uids that are allowed to be used.")]
-		public string[] MapPool = Array.Empty<string>();
+		public string[] MapPool = [];
 
 		[Desc("Delay in milliseconds before newly joined players can send chat messages.")]
 		public int FloodLimitJoinCooldown = 5000;
@@ -248,7 +248,7 @@ namespace OpenRA
 		public string Name = "Commander";
 		public Color Color = Color.FromArgb(200, 32, 32);
 		public string LastServer = "localhost:1234";
-		public Color[] CustomColors = Array.Empty<Color>();
+		public Color[] CustomColors = [];
 	}
 
 	public class SinglePlayerGameSettings
@@ -317,13 +317,13 @@ namespace OpenRA
 		public readonly ServerSettings Server = new();
 		public readonly DebugSettings Debug = new();
 		public readonly SinglePlayerGameSettings SinglePlayerSettings = new();
-		internal Dictionary<string, Hotkey> Keys = new();
+		internal Dictionary<string, Hotkey> Keys = [];
 		public readonly Dictionary<string, object> Sections;
 
 		// A direct clone of the file loaded from disk.
 		// Any changed settings will be merged over this on save,
 		// allowing us to persist any unknown configuration keys
-		readonly List<MiniYamlNode> yamlCache = new();
+		readonly List<MiniYamlNode> yamlCache = [];
 
 		public Settings(string file, Arguments args)
 		{

OpenRA.Game/Sound/Sound.cs

@@ -43,8 +43,8 @@ namespace OpenRA
 		ISoundSource videoSource;
 		ISound music;
 		ISound video;
-		readonly Dictionary<uint, ISound> currentSounds = new();
-		readonly Dictionary<string, ISound> currentNotifications = new();
+		readonly Dictionary<uint, ISound> currentSounds = [];
+		readonly Dictionary<string, ISound> currentNotifications = [];
 		public bool DummyEngine { get; }
 
 		public Sound(IPlatform platform, SoundSettings soundSettings)

OpenRA.Game/StreamExts.cs

@@ -278,7 +278,7 @@ namespace OpenRA
 			if (!string.IsNullOrEmpty(text))
 				bytes = encoding.GetBytes(text);
 			else
-				bytes = Array.Empty<byte>();
+				bytes = [];
 
 			s.Write(bytes.Length);
 			s.Write(bytes);

OpenRA.Game/Support/Arguments.cs

@@ -16,7 +16,7 @@ namespace OpenRA
 {
 	public class Arguments
 	{
-		readonly Dictionary<string, string> args = new();
+		readonly Dictionary<string, string> args = [];
 
 		public static Arguments Empty => new();
 

OpenRA.Game/Support/AssemblyLoader.cs

@@ -105,34 +105,34 @@ namespace OpenRA.Support
 		static readonly string[] NativeLibraryPrefixes;
 
 		static readonly string[] ManagedAssemblyExtensions =
-		{
+		[
 			".dll",
 			".ni.dll",
 			".exe",
 			".ni.exe"
-		};
+		];
 
 		static ManagedLoadContext()
 		{
 			if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
 			{
-				NativeLibraryPrefixes = new[] { "" };
-				NativeLibraryExtensions = new[] { ".dll" };
+				NativeLibraryPrefixes = [""];
+				NativeLibraryExtensions = [".dll"];
 			}
 			else if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
 			{
-				NativeLibraryPrefixes = new[] { "", "lib", };
-				NativeLibraryExtensions = new[] { ".dylib" };
+				NativeLibraryPrefixes = ["", "lib",];
+				NativeLibraryExtensions = [".dylib"];
 			}
 			else if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
 			{
-				NativeLibraryPrefixes = new[] { "", "lib" };
-				NativeLibraryExtensions = new[] { ".so", ".so.1" };
+				NativeLibraryPrefixes = ["", "lib"];
+				NativeLibraryExtensions = [".so", ".so.1"];
 			}
 			else
 			{
-				NativeLibraryPrefixes = Array.Empty<string>();
-				NativeLibraryExtensions = Array.Empty<string>();
+				NativeLibraryPrefixes = [];
+				NativeLibraryExtensions = [];
 			}
 		}
 
@@ -344,7 +344,7 @@ namespace OpenRA.Support
 
 		static IEnumerable<string> GetRids(RuntimeFallbacks runtimeGraph)
 		{
-			return Enumerable.Concat(new[] { runtimeGraph.Runtime }, runtimeGraph?.Fallbacks ?? Enumerable.Empty<string>());
+			return Enumerable.Concat([runtimeGraph.Runtime], runtimeGraph?.Fallbacks ?? Enumerable.Empty<string>());
 		}
 
 		static IEnumerable<string> SelectAssets(IEnumerable<string> rids, IReadOnlyCollection<RuntimeAssetGroup> groups)

OpenRA.Game/Support/Benchmark.cs

@@ -17,7 +17,7 @@ namespace OpenRA.Support
 	sealed class Benchmark
 	{
 		readonly string prefix;
-		readonly Dictionary<string, List<BenchmarkPoint>> samples = new();
+		readonly Dictionary<string, List<BenchmarkPoint>> samples = [];
 
 		public Benchmark(string prefix)
 		{

OpenRA.Game/Support/HttpQueryBuilder.cs

@@ -20,7 +20,7 @@ namespace OpenRA.Support
 	public class HttpQueryBuilder : IEnumerable<KeyValuePair<string, string>>
 	{
 		readonly string url;
-		readonly List<KeyValuePair<string, string>> parameters = new();
+		readonly List<KeyValuePair<string, string>> parameters = [];
 
 		public HttpQueryBuilder(string url)
 		{

OpenRA.Game/Support/Log.cs

@@ -42,7 +42,7 @@ namespace OpenRA
 	{
 		const int CreateLogFileMaxRetryCount = 128;
 
-		static readonly ConcurrentDictionary<string, ChannelInfo> Channels = new();
+		static readonly ConcurrentDictionary<string, ChannelInfo> Channels = [];
 		static readonly Channel<ChannelData> Channel;
 		static readonly ChannelWriter<ChannelData> ChannelWriter;
 		static readonly CancellationTokenSource CancellationToken = new();

OpenRA.Game/Support/PerfHistory.cs

@@ -16,7 +16,7 @@ namespace OpenRA.Support
 	public static class PerfHistory
 	{
 		static readonly Color[] Colors =
-		{
+		[
 			Color.Red, Color.Green,
 			Color.Orange, Color.Yellow,
 			Color.Fuchsia, Color.Lime,
@@ -24,7 +24,7 @@ namespace OpenRA.Support
 			Color.White, Color.Teal,
 			Color.Pink, Color.MediumPurple,
 			Color.Olive, Color.CornflowerBlue
-		};
+		];
 
 		static int nextColor;
 

OpenRA.Game/Support/PerfTimer.cs

@@ -56,7 +56,7 @@ namespace OpenRA.Support
 				Write();
 			else if (ticks > thresholdTicks)
 			{
-				parent.children ??= new List<PerfTimer>();
+				parent.children ??= [];
 				parent.children.Add(this);
 			}
 		}

OpenRA.Game/Support/VariableExpression.cs

@@ -24,7 +24,7 @@ namespace OpenRA.Support
 		public static readonly IReadOnlyDictionary<string, int> NoVariables = new ReadOnlyDictionary<string, int>(new Dictionary<string, int>());
 
 		public readonly string Expression;
-		readonly HashSet<string> variables = new();
+		readonly HashSet<string> variables = [];
 		public IEnumerable<string> Variables => variables;
 
 		enum CharClass { Whitespace, Operator, Mixed, Id, Digit }
@@ -717,8 +717,8 @@ namespace OpenRA.Support
 
 		sealed class AstStack
 		{
-			readonly List<Expression> expressions = new();
-			readonly List<ExpressionType> types = new();
+			readonly List<Expression> expressions = [];
+			readonly List<ExpressionType> types = [];
 
 			public ExpressionType PeekType() { return types[^1]; }
 

OpenRA.Game/Sync.cs

@@ -76,7 +76,7 @@ namespace OpenRA
 
 		static Func<object, int> GenerateHashFunc(Type t)
 		{
-			var d = new DynamicMethod($"hash_{t.Name}", typeof(int), new Type[] { typeof(object) }, t);
+			var d = new DynamicMethod($"hash_{t.Name}", typeof(int), [typeof(object)], t);
 			var il = d.GetILGenerator();
 			var this_ = il.DeclareLocal(t).LocalIndex;
 			il.Emit(OpCodes.Ldarg_0);

OpenRA.Game/TextNotificationsManager.cs

@@ -21,9 +21,9 @@ namespace OpenRA
 		static readonly string SystemMessageLabel;
 
 		public static long ChatDisabledUntil { get; internal set; }
-		public static readonly Dictionary<int, bool> MutedPlayers = new();
+		public static readonly Dictionary<int, bool> MutedPlayers = [];
 
-		static readonly List<TextNotification> NotificationsCache = new();
+		static readonly List<TextNotification> NotificationsCache = [];
 		public static IReadOnlyList<TextNotification> Notifications => NotificationsCache;
 
 		static TextNotificationsManager()

OpenRA.Game/TraitDictionary.cs

@@ -44,7 +44,7 @@ namespace OpenRA
 		static readonly Func<Type, ITraitContainer> CreateTraitContainer = t =>
 			(ITraitContainer)typeof(TraitContainer<>).MakeGenericType(t).GetConstructor(Type.EmptyTypes).Invoke(null);
 
-		readonly Dictionary<Type, ITraitContainer> traits = new();
+		readonly Dictionary<Type, ITraitContainer> traits = [];
 
 		ITraitContainer InnerGet(Type t)
 		{
@@ -143,8 +143,8 @@ namespace OpenRA
 
 		sealed class TraitContainer<T> : ITraitContainer
 		{
-			readonly List<Actor> actors = new();
-			readonly List<T> traits = new();
+			readonly List<Actor> actors = [];
+			readonly List<T> traits = [];
 
 			public int Queries { get; private set; }
 

OpenRA.Game/Traits/LintAttributes.cs

@@ -37,7 +37,7 @@ namespace OpenRA.Traits
 		public ActorReferenceAttribute(Type requiredTrait = null,
 			LintDictionaryReference dictionaryReference = LintDictionaryReference.None)
 		{
-			RequiredTraits = requiredTrait != null ? new[] { requiredTrait } : Array.Empty<Type>();
+			RequiredTraits = requiredTrait != null ? [requiredTrait] : [];
 			DictionaryReference = dictionaryReference;
 		}
 	}

OpenRA.Game/Traits/Player/FrozenActorLayer.cs

@@ -39,7 +39,7 @@ namespace OpenRA.Traits
 		readonly Actor actor;
 		readonly ICreatesFrozenActors frozenTrait;
 		readonly Shroud shroud;
-		readonly List<WPos> targetablePositions = new();
+		readonly List<WPos> targetablePositions = [];
 
 		public Player Viewer { get; }
 		public Player Owner { get; private set; }
@@ -75,8 +75,8 @@ namespace OpenRA.Traits
 
 		public Polygon MouseBounds = Polygon.Empty;
 
-		static readonly IRenderable[] NoRenderables = Array.Empty<IRenderable>();
-		static readonly Rectangle[] NoBounds = Array.Empty<Rectangle>();
+		static readonly IRenderable[] NoRenderables = [];
+		static readonly Rectangle[] NoBounds = [];
 
 		int flashTicks;
 		TintModifiers flashModifiers;
@@ -261,7 +261,7 @@ namespace OpenRA.Traits
 			binSize = info.BinSize;
 			world = self.World;
 			owner = self.Owner;
-			frozenActorsById = new Dictionary<uint, FrozenActor>();
+			frozenActorsById = [];
 
 			partitionedFrozenActors = new SpatiallyPartitioned<FrozenActor>(
 				world.Map.MapSize.X, world.Map.MapSize.Y, binSize);
@@ -329,7 +329,7 @@ namespace OpenRA.Traits
 					VisibilityHash += hash;
 				else if (frozenActor.Actor == null)
 				{
-					frozenActorsToRemove ??= new List<FrozenActor>();
+					frozenActorsToRemove ??= [];
 					frozenActorsToRemove.Add(frozenActor);
 				}
 			}

OpenRA.Game/Traits/Player/Shroud.cs

@@ -96,7 +96,7 @@ namespace OpenRA.Traits
 		readonly Map map;
 
 		// Individual shroud modifier sources (type and area)
-		readonly Dictionary<object, ShroudSource> sources = new();
+		readonly Dictionary<object, ShroudSource> sources = [];
 
 		// Per-cell count of each source type, used to resolve the final cell type
 		readonly ProjectedCellLayer<short> passiveVisibleCount;

OpenRA.Game/Traits/Target.cs

@@ -18,7 +18,7 @@ namespace OpenRA.Traits
 	public enum TargetType : byte { Invalid, Actor, Terrain, FrozenActor }
 	public readonly struct Target : IEquatable<Target>
 	{
-		public static readonly Target[] None = Array.Empty<Target>();
+		public static readonly Target[] None = [];
 		public static readonly Target Invalid = default;
 		public Actor Actor { get; }
 		public FrozenActor FrozenActor { get; }
@@ -34,7 +34,7 @@ namespace OpenRA.Traits
 		{
 			type = TargetType.Terrain;
 			this.terrainCenterPosition = terrainCenterPosition;
-			this.terrainPositions = terrainPositions ?? new[] { terrainCenterPosition };
+			this.terrainPositions = terrainPositions ?? [terrainCenterPosition];
 
 			Actor = null;
 			FrozenActor = null;
@@ -47,7 +47,7 @@ namespace OpenRA.Traits
 		{
 			type = TargetType.Terrain;
 			terrainCenterPosition = w.Map.CenterOfSubCell(c, subCell);
-			terrainPositions = new[] { terrainCenterPosition };
+			terrainPositions = [terrainCenterPosition];
 			cell = c;
 			this.subCell = subCell;
 
@@ -172,7 +172,7 @@ namespace OpenRA.Traits
 		}
 
 		// Positions available to target for range checks
-		static readonly WPos[] NoPositions = Array.Empty<WPos>();
+		static readonly WPos[] NoPositions = [];
 		public IEnumerable<WPos> Positions
 		{
 			get

OpenRA.Game/Traits/World/Faction.cs

@@ -25,7 +25,7 @@ namespace OpenRA.Traits
 		public readonly string InternalName = null;
 
 		[Desc("Pick a random faction as the player's faction out of this list.")]
-		public readonly HashSet<string> RandomFactionMembers = new();
+		public readonly HashSet<string> RandomFactionMembers = [];
 
 		[Desc("The side that the faction belongs to. For example, England belongs to the 'Allies' side.")]
 		public readonly string Side = null;

OpenRA.Game/Traits/World/ScreenMap.cs

@@ -41,21 +41,21 @@ namespace OpenRA.Traits
 
 	public class ScreenMap : IWorldLoaded
 	{
-		static readonly IEnumerable<FrozenActor> NoFrozenActors = Array.Empty<FrozenActor>();
+		static readonly IEnumerable<FrozenActor> NoFrozenActors = [];
 		readonly Func<FrozenActor, bool> frozenActorIsValid = fa => fa.IsValid;
 		readonly Func<Actor, bool> actorIsInWorld = a => a.IsInWorld;
 		readonly Func<Actor, ActorBoundsPair> selectActorAndBounds;
 		readonly Cache<Player, SpatiallyPartitioned<FrozenActor>> partitionedMouseFrozenActors;
 		readonly SpatiallyPartitioned<Actor> partitionedMouseActors;
-		readonly Dictionary<Actor, ActorBoundsPair> partitionedMouseActorBounds = new();
+		readonly Dictionary<Actor, ActorBoundsPair> partitionedMouseActorBounds = [];
 
 		readonly Cache<Player, SpatiallyPartitioned<FrozenActor>> partitionedRenderableFrozenActors;
 		readonly SpatiallyPartitioned<Actor> partitionedRenderableActors;
 		readonly SpatiallyPartitioned<IEffect> partitionedRenderableEffects;
 
 		// Updates are done in one pass to ensure all bound changes have been applied
-		readonly HashSet<Actor> addOrUpdateActors = new();
-		readonly HashSet<Actor> removeActors = new();
+		readonly HashSet<Actor> addOrUpdateActors = [];
+		readonly HashSet<Actor> removeActors = [];
 		readonly Cache<Player, HashSet<FrozenActor>> addOrUpdateFrozenActors;
 		readonly Cache<Player, HashSet<FrozenActor>> removeFrozenActors;
 
@@ -77,8 +77,8 @@ namespace OpenRA.Traits
 			partitionedRenderableActors = new SpatiallyPartitioned<Actor>(width, height, info.BinSize);
 			partitionedRenderableEffects = new SpatiallyPartitioned<IEffect>(width, height, info.BinSize);
 
-			addOrUpdateFrozenActors = new Cache<Player, HashSet<FrozenActor>>(_ => new HashSet<FrozenActor>());
-			removeFrozenActors = new Cache<Player, HashSet<FrozenActor>>(_ => new HashSet<FrozenActor>());
+			addOrUpdateFrozenActors = new Cache<Player, HashSet<FrozenActor>>(_ => []);
+			removeFrozenActors = new Cache<Player, HashSet<FrozenActor>>(_ => []);
 		}
 
 		public void WorldLoaded(World w, WorldRenderer wr) { worldRenderer = wr; }

OpenRA.Game/Traits/World/ScreenShaker.cs

@@ -29,7 +29,7 @@ namespace OpenRA.Traits
 	{
 		readonly ScreenShakerInfo info;
 		WorldRenderer worldRenderer;
-		readonly List<ShakeEffect> shakeEffects = new();
+		readonly List<ShakeEffect> shakeEffects = [];
 		int ticks = 0;
 
 		public ScreenShaker(ScreenShakerInfo info)

OpenRA.Game/UtilityCommands/RegisterModCommand.cs

@@ -32,7 +32,7 @@ namespace OpenRA.UtilityCommands
 			if (args[2] == "user" || args[2] == "both")
 				type |= ModRegistration.User;
 
-			new ExternalMods().Register(utility.ModData.Manifest, args[1], Enumerable.Empty<string>(), type);
+			new ExternalMods().Register(utility.ModData.Manifest, args[1], [], type);
 		}
 	}
 }

OpenRA.Game/WAngle.cs

@@ -172,7 +172,7 @@ namespace OpenRA
 		public override string ToString() { return Angle.ToStringInvariant(); }
 
 		static readonly int[] CosineTable =
-		{
+		[
 			1024, 1023, 1023, 1023, 1023, 1023, 1023, 1023, 1022, 1022, 1022, 1021,
 			1021, 1020, 1020, 1019, 1019, 1018, 1017, 1017, 1016, 1015, 1014, 1013,
 			1012, 1011, 1010, 1009, 1008, 1007, 1006, 1005, 1004, 1003, 1001, 1000,
@@ -192,10 +192,10 @@ namespace OpenRA
 			236, 230, 224, 218, 212, 205, 199, 193, 187, 181, 175, 168, 162, 156,
 			150, 144, 137, 131, 125, 119, 112, 106, 100, 94, 87, 81, 75, 69, 62,
 			56, 50, 43, 37, 31, 25, 18, 12, 6, 0
-		};
+		];
 
 		static readonly int[] TanTable =
-		{
+		[
 			0, 6, 12, 18, 25, 31, 37, 44, 50, 56, 62, 69, 75, 81, 88, 94, 100, 107,
 			113, 119, 126, 132, 139, 145, 151, 158, 164, 171, 177, 184, 190, 197,
 			203, 210, 216, 223, 229, 236, 243, 249, 256, 263, 269, 276, 283, 290,
@@ -216,7 +216,7 @@ namespace OpenRA
 			5499, 5693, 5901, 6124, 6364, 6622, 6903, 7207, 7539, 7902, 8302, 8743,
 			9233, 9781, 10396, 11094, 11891, 12810, 13882, 15148, 16667, 18524, 20843,
 			23826, 27801, 33366, 41713, 55622, 83438, 166883, int.MaxValue
-		};
+		];
 
 		#region Scripting interface
 

OpenRA.Game/Widgets/ChromeMetrics.cs

@@ -16,14 +16,14 @@ namespace OpenRA.Widgets
 {
 	public static class ChromeMetrics
 	{
-		static Dictionary<string, string> data = new();
+		static Dictionary<string, string> data = [];
 
 		public static void Initialize(ModData modData)
 		{
 			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, stringPool: stringPool)));
-			data = new Dictionary<string, string>();
+			data = [];
 			foreach (var m in metrics)
 				foreach (var n in m.Value.Nodes)
 					data[n.Key] = n.Value.Value;

OpenRA.Game/Widgets/Widget.cs

@@ -28,7 +28,7 @@ namespace OpenRA.Widgets
 
 		public static TickTime LastTickTime = new(() => Timestep, Game.RunTime);
 
-		static readonly Stack<Widget> WindowList = new();
+		static readonly Stack<Widget> WindowList = [];
 
 		public static Widget MouseFocusWidget;
 		public static Widget KeyboardFocusWidget;
@@ -60,7 +60,7 @@ namespace OpenRA.Widgets
 
 		public static Widget OpenWindow(string id)
 		{
-			return OpenWindow(id, new WidgetArgs());
+			return OpenWindow(id, []);
 		}
 
 		public static Widget OpenWindow(string id, WidgetArgs args)
@@ -208,7 +208,7 @@ namespace OpenRA.Widgets
 	{
 		string defaultCursor = null;
 
-		public readonly List<Widget> Children = new();
+		public readonly List<Widget> Children = [];
 
 		// Info defined in YAML
 		public string Id = null;
@@ -216,7 +216,7 @@ namespace OpenRA.Widgets
 		public IntegerExpression Y;
 		public IntegerExpression Width;
 		public IntegerExpression Height;
-		public string[] Logic = Array.Empty<string>();
+		public string[] Logic = [];
 		public ChromeLogic[] LogicObjects { get; private set; }
 		public bool Visible = true;
 		public bool IgnoreMouseOver;
@@ -288,7 +288,7 @@ namespace OpenRA.Widgets
 
 			var substitutions = args.TryGetValue("substitutions", out var subs) ?
 				new Dictionary<string, int>((Dictionary<string, int>)subs) :
-				new Dictionary<string, int>();
+				[];
 
 			substitutions.Add("WINDOW_WIDTH", Game.Renderer.Resolution.Width);
 			substitutions.Add("WINDOW_HEIGHT", Game.Renderer.Resolution.Height);
@@ -668,7 +668,7 @@ namespace OpenRA.Widgets
 
 	public sealed class Mediator
 	{
-		readonly TypeDictionary types = new();
+		readonly TypeDictionary types = [];
 
 		public void Subscribe<T>(T instance)
 		{

OpenRA.Game/Widgets/WidgetLoader.cs

@@ -18,7 +18,7 @@ namespace OpenRA
 {
 	public class WidgetLoader
 	{
-		readonly Dictionary<string, MiniYamlNode> widgets = new();
+		readonly Dictionary<string, MiniYamlNode> widgets = [];
 		readonly ModData modData;
 
 		public WidgetLoader(ModData modData)

OpenRA.Game/World.cs

@@ -29,14 +29,14 @@ namespace OpenRA
 	public sealed class World : IDisposable
 	{
 		internal readonly TraitDictionary TraitDict = new();
-		readonly SortedDictionary<uint, Actor> actors = new();
-		readonly List<IEffect> effects = new();
-		readonly List<IEffect> unpartitionedEffects = new();
-		readonly List<ISync> syncedEffects = new();
+		readonly SortedDictionary<uint, Actor> actors = [];
+		readonly List<IEffect> effects = [];
+		readonly List<IEffect> unpartitionedEffects = [];
+		readonly List<ISync> syncedEffects = [];
 		readonly GameSettings gameSettings;
 		readonly ModData modData;
 
-		readonly Queue<Action<World>> frameEndActions = new();
+		readonly Queue<Action<World>> frameEndActions = [];
 
 		public readonly GameSpeed GameSpeed;
 
@@ -52,7 +52,7 @@ namespace OpenRA
 		public LongBitSet<PlayerBitMask> AllPlayersMask = default;
 		public readonly LongBitSet<PlayerBitMask> NoPlayersMask = default;
 
-		public Player[] Players = Array.Empty<Player>();
+		public Player[] Players = [];
 
 		public event Action<Player> RenderPlayerChanged;
 
@@ -213,7 +213,7 @@ namespace OpenRA
 			LocalRandom = new MersenneTwister();
 
 			var worldActorType = type == WorldType.Editor ? SystemActors.EditorWorld : SystemActors.World;
-			WorldActor = CreateActor(worldActorType.ToString(), new TypeDictionary());
+			WorldActor = CreateActor(worldActorType.ToString(), []);
 			ActorMap = WorldActor.Trait<IActorMap>();
 			ScreenMap = WorldActor.Trait<ScreenMap>();
 			Selection = WorldActor.Trait<ISelection>();
@@ -399,7 +399,7 @@ namespace OpenRA
 
 		public int WorldTick { get; private set; }
 
-		readonly Dictionary<int, MiniYaml> gameSaveTraitData = new();
+		readonly Dictionary<int, MiniYaml> gameSaveTraitData = [];
 		internal void AddGameSaveTraitData(int traitIndex, MiniYaml yaml)
 		{
 			gameSaveTraitData[traitIndex] = yaml;