reduce remaining uses of LINQ on warmer paths

src/SMAPI/Framework/Content/ContentCache.cs

@@ -2,7 +2,6 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Diagnostics.Contracts;
-using System.Linq;
 using StardewModdingAPI.Toolkit.Utilities;
 
 namespace StardewModdingAPI.Framework.Content;
@@ -117,7 +116,7 @@ internal class ContentCache
             this.Remove(key, dispose);
 
         return removed.Count == 0
-            ? Enumerable.Empty<string>() // let GC collect the list in gen0 instead of potentially living longer
+            ? Array.Empty<string>() // let GC collect the list in gen0 instead of potentially living longer
             : removed;
     }
 }

src/SMAPI/Framework/ContentManagers/GameContentManager.cs

@@ -170,7 +170,7 @@ internal class GameContentManager : BaseContentManager
                 return null;
             }
 
-            loader = loadOperations.OrderByDescending(p => p.Priority).FirstOrDefault();
+            loader = loadOperations.MaxBy(p => p.Priority);
         }
         if (loader == null)
             return null;

src/SMAPI/Framework/Extensions/ClickableMenuExtensions.cs

@@ -1,5 +1,4 @@
 using System.Collections.Generic;
-using System.Linq;
 using StardewValley.Menus;
 
 namespace StardewModdingAPI.Framework.Extensions;
@@ -13,13 +12,12 @@ internal static class ClickableMenuExtensions
         /// <summary>Get a string representation of the menu chain to the given menu (including the specified menu), in parent to child order.</summary>
         public string GetMenuChainLabel()
         {
-            static IEnumerable<IClickableMenu> GetAncestors(IClickableMenu menu)
-            {
-                for (; menu != null; menu = menu.GetParentMenu())
-                    yield return menu;
-            }
+            Stack<string> chain = [];
 
-            return string.Join(" > ", GetAncestors(menu).Reverse().Select(p => p.GetType().FullName));
+            for (; menu != null; menu = menu.GetParentMenu())
+                chain.Push(menu.GetType().FullName!);
+
+            return string.Join(" > ", chain);
         }
     }
 }

src/SMAPI/Framework/ModHelpers/GameContentHelper.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Linq;
 using StardewModdingAPI.Framework.Content;
 using StardewModdingAPI.Framework.ContentManagers;
 using StardewModdingAPI.Framework.Exceptions;

src/SMAPI/Framework/ModLoading/AssemblyLoader.cs

@@ -114,12 +114,14 @@ internal class AssemblyLoader : IDisposable
         // get referenced local assemblies
         AssemblyParseResult[] assemblies;
         {
-            HashSet<string> visitedAssemblyNames = new( // don't try loading assemblies that are already loaded
-                from assembly in AppDomain.CurrentDomain.GetAssemblies()
-                let name = assembly.GetName().Name
-                where name != null
-                select name
-            );
+            // don't try loading assemblies that are already loaded
+            HashSet<string> visitedAssemblyNames = [];
+            foreach (Assembly assembly in AppDomain.CurrentDomain.GetAssemblies())
+            {
+                string? name = assembly.GetName().Name;
+                if (name != null)
+                    visitedAssemblyNames.Add(name);
+            }
             assemblies = this.GetReferencedLocalAssemblies(assemblyFile, visitedAssemblyNames, this.AssemblyDefinitionResolver).ToArray();
         }
 

src/SMAPI/Framework/ModLoading/Finders/ReferenceToInvalidMemberFinder.cs

@@ -1,6 +1,5 @@
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
-using System.Linq;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
 using StardewModdingAPI.Framework.ModLoading.Framework;
@@ -41,13 +40,25 @@ internal class ReferenceToInvalidMemberFinder : BaseInstructionHandler
         FieldReference? fieldRef = RewriteHelper.AsFieldReference(instruction);
         if (fieldRef != null && this.ShouldValidate(fieldRef.DeclaringType))
         {
-            FieldDefinition? targetField = fieldRef.DeclaringType.Resolve()?.Fields.FirstOrDefault(p => p.Name == fieldRef.Name);
+            // resolve field
+            FieldDefinition? targetField = null;
+            if (fieldRef.DeclaringType.Resolve() is { } declaringType)
+            {
+                foreach (FieldDefinition field in declaringType.Fields)
+                {
+                    if (field.Name == fieldRef.Name)
+                    {
+                        targetField = field;
+                        break;
+                    }
+                }
+            }
 
-            // wrong return type
+            // detect wrong return type
             if (targetField != null && !RewriteHelper.LooksLikeSameType(fieldRef.FieldType, targetField.FieldType))
                 this.MarkFlag(InstructionHandleResult.NotCompatible, $"reference to {this.GetMemberDisplayName(fieldRef)} (field returns {this.GetFriendlyTypeName(targetField.FieldType)}, not {this.GetFriendlyTypeName(fieldRef.FieldType)})");
 
-            // missing
+            // detect missing
             else if (targetField == null || targetField.HasConstant || !RewriteHelper.HasSameNamespaceAndName(fieldRef.DeclaringType, targetField.DeclaringType))
                 this.MarkFlag(InstructionHandleResult.NotCompatible, $"reference to {this.GetMemberDisplayName(fieldRef)} (no such field)");
 

src/SMAPI/Framework/ModLoading/Framework/RecursiveRewriter.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
-using System.Linq;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
 using Mono.Collections.Generic;
@@ -292,10 +291,18 @@ internal class RecursiveRewriter
             if (curChanged)
             {
                 // get constructor
-                MethodDefinition? constructor = (newAttrType ?? attribute.AttributeType)
-                    .Resolve()
-                    ?.Methods
-                    .FirstOrDefault(method => method.IsConstructor && RewriteHelper.HasMatchingSignature(method, attribute.Constructor));
+                MethodDefinition? constructor = null;
+                if ((newAttrType ?? attribute.AttributeType).Resolve() is { } typeDef)
+                {
+                    foreach (MethodDefinition method in typeDef.Methods)
+                    {
+                        if (method.IsConstructor && RewriteHelper.HasMatchingSignature(method, attribute.Constructor))
+                        {
+                            constructor = method;
+                            break;
+                        }
+                    }
+                }
                 if (constructor == null)
                     throw new InvalidOperationException($"Can't rewrite attribute type '{attribute.AttributeType.FullName}' to '{newAttrType?.FullName}', no equivalent constructor found.");
 

src/SMAPI/Framework/ModLoading/Rewriters/HeuristicFieldRewriter.cs

@@ -1,6 +1,5 @@
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
-using System.Linq;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
 using StardewModdingAPI.Framework.ModLoading.Framework;
@@ -67,17 +66,30 @@ internal class HeuristicFieldRewriter : BaseInstructionHandler
     /// <param name="fieldRef">The field reference.</param>
     /// <param name="declaringType">The type on which the field was defined.</param>
     /// <param name="isRead">Whether the field is being read; else it's being written to.</param>
-    private bool TryRewriteToProperty(ModuleDefinition module, Instruction instruction, FieldReference fieldRef, TypeDefinition declaringType, bool isRead)
+    private bool TryRewriteToProperty(ModuleDefinition module, Instruction instruction, FieldReference fieldRef, TypeDefinition? declaringType, bool isRead)
     {
         // get equivalent property
-        PropertyDefinition? property = declaringType?.Properties.FirstOrDefault(p => p.Name == fieldRef.Name);
-        MethodDefinition? method = isRead ? property?.GetMethod : property?.SetMethod;
-        if (method == null)
+        MethodDefinition? accessor = null;
+        if (declaringType is not null)
+        {
+            PropertyDefinition? targetProperty = null;
+            foreach (PropertyDefinition property in declaringType.Properties)
+            {
+                if (property.Name == fieldRef.Name)
+                {
+                    targetProperty = property;
+                    break;
+                }
+            }
+
+            accessor = isRead ? targetProperty?.GetMethod : targetProperty?.SetMethod;
+        }
+        if (accessor is null)
             return false;
 
         // rewrite field to property
         instruction.OpCode = OpCodes.Call;
-        instruction.Operand = module.ImportReference(method);
+        instruction.Operand = module.ImportReference(accessor);
 
         this.Phrases.Add($"{fieldRef.DeclaringType.Name}.{fieldRef.Name} (field => property)");
         return this.MarkRewritten();

src/SMAPI/Framework/ModLoading/Rewriters/HeuristicMethodRewriter.cs

@@ -1,8 +1,8 @@
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
-using System.Linq;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
+using Mono.Collections.Generic;
 using StardewModdingAPI.Framework.ModLoading.Framework;
 
 namespace StardewModdingAPI.Framework.ModLoading.Rewriters;
@@ -46,6 +46,7 @@ internal class HeuristicMethodRewriter : BaseInstructionHandler
             return false;
 
         // get method definition
+        int firstMissingIndex = methodRef.Parameters.Count;
         MethodDefinition? method = null;
         foreach (MethodDefinition match in type.Methods)
         {
@@ -53,11 +54,11 @@ internal class HeuristicMethodRewriter : BaseInstructionHandler
                 continue;
 
             // reference matches initial parameters of definition
-            if (methodRef.Parameters.Count >= match.Parameters.Count || !this.InitialParametersMatch(methodRef, match))
+            if (firstMissingIndex >= match.Parameters.Count || !this.InitialParametersMatch(methodRef, match))
                 continue;
 
             // all remaining parameters in definition are optional
-            if (!match.Parameters.Skip(methodRef.Parameters.Count).All(p => p.IsOptional))
+            if (!this.RemainingParametersAreOptional(match.Parameters, startAt: firstMissingIndex))
                 continue;
 
             method = match;
@@ -67,15 +68,14 @@ internal class HeuristicMethodRewriter : BaseInstructionHandler
             return false;
 
         // get instructions to inject parameter values
-        var loadInstructions = method.Parameters.Skip(methodRef.Parameters.Count)
-            .Select(p => RewriteHelper.GetLoadValueInstruction(p.Constant))
-            .ToArray();
-
-        // skip if invalid
-        foreach (Instruction? loadInstruction in loadInstructions)
+        Instruction[] loadInstructions = new Instruction[method.Parameters.Count - firstMissingIndex];
+        for (int i = 0; i + firstMissingIndex < method.Parameters.Count; i++)
         {
+            Instruction? loadInstruction = RewriteHelper.GetLoadValueInstruction(method.Parameters[i + firstMissingIndex].Constant);
             if (loadInstruction is null)
                 return false; // SMAPI needs to load the value onto the stack before the method call, but the optional parameter type wasn't recognized
+
+            loadInstructions[i] = loadInstruction;
         }
 
         // rewrite method reference
@@ -114,4 +114,18 @@ internal class HeuristicMethodRewriter : BaseInstructionHandler
 
         return true;
     }
+
+    /// <summary>Get whether all parameters starting from the given index are marked optional.</summary>
+    /// <param name="parameters">The parameters to check.</param>
+    /// <param name="startAt">The index of the first parameter to check.</param>
+    private bool RemainingParametersAreOptional(Collection<ParameterDefinition> parameters, int startAt)
+    {
+        for (int i = startAt; i < parameters.Count; i++)
+        {
+            if (!parameters[i].IsOptional)
+                return false;
+        }
+
+        return true;
+    }
 }

src/SMAPI/Framework/ModLoading/TypeReferenceComparer.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using Mono.Cecil;
 
 namespace StardewModdingAPI.Framework.ModLoading;
@@ -73,12 +72,12 @@ internal class TypeReferenceComparer : IEqualityComparer<TypeReference?>
                 typeNameB = this.MapPlaceholder(placeholder: typeNameB, type: typeNameA, map: tokenMap);
 
             // compare inner tokens
-            string[] symbolsA = this.GetTypeSymbols(typeNameA).ToArray();
-            string[] symbolsB = this.GetTypeSymbols(typeNameB).ToArray();
-            if (symbolsA.Length != symbolsB.Length)
+            IReadOnlyList<string> symbolsA = this.GetTypeSymbols(typeNameA);
+            IReadOnlyList<string> symbolsB = this.GetTypeSymbols(typeNameB);
+            if (symbolsA.Count != symbolsB.Count)
                 return false;
 
-            for (int i = 0; i < symbolsA.Length; i++)
+            for (int i = 0; i < symbolsA.Count; i++)
             {
                 if (!HeuristicallyEqualsImpl(symbolsA[i], symbolsB[i], tokenMap))
                     return false;
@@ -106,10 +105,11 @@ internal class TypeReferenceComparer : IEqualityComparer<TypeReference?>
 
     /// <summary>Get the top-level type symbols in a type name (e.g. <code>List</code> and <code>NetRef&lt;T&gt;</code> in <code>List&lt;NetRef&lt;T&gt;&gt;</code>)</summary>
     /// <param name="typeName">The full type name.</param>
-    private IEnumerable<string> GetTypeSymbols(string typeName)
+    private IReadOnlyList<string> GetTypeSymbols(string typeName)
     {
-        int openGenerics = 0;
+        List<string> symbols = [];
 
+        int openGenerics = 0;
         Queue<char> queue = new(typeName);
         string symbol = "";
         while (queue.Count > 0)
@@ -129,7 +129,7 @@ internal class TypeReferenceComparer : IEqualityComparer<TypeReference?>
                     {
                         // start new generic symbol
                         case 0:
-                            yield return symbol;
+                            symbols.Add(symbol);
                             symbol = "";
                             openGenerics++;
                             break;
@@ -152,7 +152,7 @@ internal class TypeReferenceComparer : IEqualityComparer<TypeReference?>
 
                         // start next generic symbol
                         case 1:
-                            yield return symbol;
+                            symbols.Add(symbol);
                             symbol = "";
                             break;
 
@@ -174,7 +174,7 @@ internal class TypeReferenceComparer : IEqualityComparer<TypeReference?>
 
                         // end generic symbol
                         case 1:
-                            yield return symbol;
+                            symbols.Add(symbol);
                             symbol = "";
                             openGenerics--;
                             break;
@@ -195,6 +195,8 @@ internal class TypeReferenceComparer : IEqualityComparer<TypeReference?>
         }
 
         if (symbol != "")
-            yield return symbol;
+            symbols.Add(symbol);
+
+        return symbols;
     }
 }

src/SMAPI/Framework/SCore.cs

@@ -883,7 +883,7 @@ internal class SCore : IDisposable
                     string context = $"Context: loaded save '{Constants.SaveFolderName}', starting {Game1.currentSeason} {Game1.dayOfMonth} Y{Game1.year}, locale set to {this.ContentCore.GetLocale()}.";
                     if (Context.IsMultiplayer)
                     {
-                        int onlineCount = Game1.getOnlineFarmers().Count();
+                        int onlineCount = Game1.getOnlineFarmers().Count;
                         context += $" {(Context.IsMainPlayer ? "Main player" : "Farmhand")} with {onlineCount} {(onlineCount == 1 ? "player" : "players")} online.";
                     }
                     else

src/SMAPI/Framework/SGameRunner.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using Microsoft.Xna.Framework;
 using Microsoft.Xna.Framework.Graphics;
 using StardewModdingAPI.Enums;
@@ -145,9 +144,13 @@ internal class SGameRunner : GameRunner
     /// <param name="playerId">The player ID to check.</param>
     public int? GetScreenId(long playerId)
     {
-        return this.gameInstances
-            .FirstOrDefault(p => ((SGame)p).PlayerId == playerId)
-            ?.instanceId;
+        foreach (Game1 gameInstance in this.gameInstances)
+        {
+            if (((SGame)gameInstance).PlayerId == playerId)
+                return gameInstance.instanceId;
+        }
+
+        return null;
     }
 
 

src/SMAPI/Framework/StateTracking/FieldWatchers/ComparableListWatcher.cs

@@ -1,5 +1,4 @@
 using System.Collections.Generic;
-using System.Linq;
 
 namespace StardewModdingAPI.Framework.StateTracking.FieldWatchers;
 
@@ -71,8 +70,16 @@ internal class ComparableListWatcher<TValue> : BaseDisposableWatcher, ICollectio
 
         // detect changes
         HashSet<TValue> curValues = new HashSet<TValue>(this.CurrentValues, this.LastValues.Comparer);
-        this.RemovedImpl.AddRange(from value in this.LastValues where !curValues.Contains(value) select value);
-        this.AddedImpl.AddRange(from value in curValues where !this.LastValues.Contains(value) select value);
+        foreach (TValue value in this.LastValues)
+        {
+            if (!curValues.Contains(value))
+                this.RemovedImpl.Add(value);
+        }
+        foreach (TValue value in curValues)
+        {
+            if (!this.LastValues.Contains(value))
+                this.AddedImpl.Add(value);
+        }
         this.LastValues = curValues;
     }
 

src/SMAPI/Framework/StateTracking/FieldWatchers/ObservableCollectionWatcher.cs

@@ -1,7 +1,6 @@
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Collections.Specialized;
-using System.Linq;
 
 namespace StardewModdingAPI.Framework.StateTracking.FieldWatchers;
 
@@ -86,25 +85,31 @@ internal class ObservableCollectionWatcher<TValue> : BaseDisposableWatcher, ICol
     /// <param name="e">The event arguments.</param>
     private void OnCollectionChanged(object? sender, NotifyCollectionChangedEventArgs e)
     {
+        // clear
         if (e.Action == NotifyCollectionChangedAction.Reset)
         {
             this.RemovedImpl.AddRange(this.PreviousValues);
             this.PreviousValues.Clear();
+            return;
         }
-        else
-        {
-            TValue[]? added = e.NewItems?.Cast<TValue>().ToArray();
-            TValue[]? removed = e.OldItems?.Cast<TValue>().ToArray();
 
-            if (removed != null)
+        // removed items
+        if (e.OldItems != null)
+        {
+            foreach (TValue value in e.OldItems)
+                this.RemovedImpl.Add(value);
+            this.PreviousValues.RemoveRange(e.OldStartingIndex, e.OldItems.Count);
+        }
+
+        // added items
+        if (e.NewItems != null)
+        {
+            int insertAt = e.NewStartingIndex;
+            foreach (TValue value in e.NewItems)
             {
-                this.RemovedImpl.AddRange(removed);
-                this.PreviousValues.RemoveRange(e.OldStartingIndex, removed.Length);
-            }
-            if (added != null)
-            {
-                this.AddedImpl.AddRange(added);
-                this.PreviousValues.InsertRange(e.NewStartingIndex, added);
+                this.AddedImpl.Add(value);
+                this.PreviousValues.Insert(insertAt, value);
+                insertAt++;
             }
         }
     }

src/SMAPI/Framework/StateTracking/Snapshots/PlayerSnapshot.cs

@@ -28,8 +28,7 @@ internal class PlayerSnapshot
     /// <summary>Tracks changes to the player's skill levels.</summary>
     public IDictionary<SkillType, SnapshotDiff<int>> Skills { get; } =
         Enum
-            .GetValues(typeof(SkillType))
-            .Cast<SkillType>()
+            .GetValues<SkillType>()
             .ToDictionary(skill => skill, _ => new SnapshotDiff<int>());
 
     /// <summary>Get a list of inventory changes.</summary>

src/SMAPI/Integrations/GenericModConfigMenu/JsonSettingsWrapper.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Linq;
 using System.Text;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
@@ -163,7 +162,7 @@ internal class JsonSettingsWrapper
         {
             oldSet = new HashSet<string>(oldSet, StringComparer.OrdinalIgnoreCase);
 
-            bool changed = newValue.Count != oldSet.Count || !oldSet.All(newValue.Contains);
+            bool changed = newValue.Count != oldSet.Count || !oldSet.IsSubsetOf(newValue);
             if (changed)
             {
                 this.Properties[fieldName] = JToken.FromObject(newValue);

src/SMAPI/Metadata/CoreAssetPropagator.cs

@@ -754,8 +754,11 @@ internal class CoreAssetPropagator
             {
                 List<NPC> characters = [];
 
-                foreach (NPC character in this.GetLocations().SelectMany(p => p.characters))
-                    characters.Add(character);
+                foreach (GameLocation location in this.GetLocations())
+                {
+                    foreach (NPC character in location.characters)
+                        characters.Add(character);
+                }
 
                 if (Game1.CurrentEvent?.actors != null)
                 {
@@ -823,9 +826,9 @@ internal class CoreAssetPropagator
                 // get child locations
                 if (buildingInteriors)
                 {
-                    foreach (GameLocation location in locations.Select(p => p.Location).ToArray())
+                    foreach (LocationInfo location in locations.ToArray())
                     {
-                        foreach (Building building in location.buildings)
+                        foreach (Building building in location.Location.buildings)
                         {
                             GameLocation indoors = building.indoors.Value;
                             if (indoors is not null)

src/SMAPI/Program.cs

@@ -2,7 +2,6 @@ using System;
 using System.Collections.Generic;
 using System.Globalization;
 using System.IO;
-using System.Linq;
 using System.Reflection;
 using System.Threading;
 using StardewModdingAPI.Framework;

src/SMAPI/Utilities/KeybindList.cs

@@ -152,7 +152,13 @@ public class KeybindList
     /// <summary>Get the keybind which is currently down, if any. If there are multiple keybinds down, the first one is returned.</summary>
     public Keybind? GetKeybindCurrentlyDown()
     {
-        return this.Keybinds.FirstOrDefault(p => p.GetState().IsDown());
+        foreach (Keybind keybind in this.Keybinds)
+        {
+            if (keybind.GetState().IsDown())
+                return keybind;
+        }
+
+        return null;
     }
 
     /// <summary>Get a string representation of the input binding.</summary>
@@ -161,6 +167,6 @@ public class KeybindList
     {
         return this.Keybinds.Length > 0
             ? string.Join(", ", this.Keybinds.Select(p => p.ToString()))
-            : SButton.None.ToString();
+            : nameof(SButton.None);
     }
 }