merge field rewriters to reduce rewrite iterations

docs/release-notes.md

@@ -8,6 +8,7 @@
   * Added automatic save recovery when the custom farm type isn't available anymore.
   * Added the new game build number to the SMAPI console + log.
   * The installer now detects Xbox app game folders.
+  * Reduced mod loading time a bit.
   * Fixed extra newlines shown in the console in non-developer mode.
   * Fixed macOS launch issue when using some terminals (thanks to bruce2409!).
   * Fixed Linux/macOS terminal ignoring backspace in Stardew Valley 1.5.5+.

src/SMAPI/Framework/ModLoading/Framework/RewriteHelper.cs

@@ -13,7 +13,7 @@ namespace StardewModdingAPI.Framework.ModLoading.Framework
         ** Fields
         *********/
         /// <summary>The comparer which heuristically compares type definitions.</summary>
-        private static readonly TypeReferenceComparer TypeDefinitionComparer = new TypeReferenceComparer();
+        private static readonly TypeReferenceComparer TypeDefinitionComparer = new();
 
 
         /*********
@@ -28,28 +28,6 @@ namespace StardewModdingAPI.Framework.ModLoading.Framework
                 : null;
         }
 
-        /// <summary>Get whether the field is a reference to the expected type and field.</summary>
-        /// <param name="instruction">The IL instruction.</param>
-        /// <param name="fullTypeName">The full type name containing the expected field.</param>
-        /// <param name="fieldName">The name of the expected field.</param>
-        public static bool IsFieldReferenceTo(Instruction instruction, string fullTypeName, string fieldName)
-        {
-            FieldReference fieldRef = RewriteHelper.AsFieldReference(instruction);
-            return RewriteHelper.IsFieldReferenceTo(fieldRef, fullTypeName, fieldName);
-        }
-
-        /// <summary>Get whether the field is a reference to the expected type and field.</summary>
-        /// <param name="fieldRef">The field reference to check.</param>
-        /// <param name="fullTypeName">The full type name containing the expected field.</param>
-        /// <param name="fieldName">The name of the expected field.</param>
-        public static bool IsFieldReferenceTo(FieldReference fieldRef, string fullTypeName, string fieldName)
-        {
-            return
-                fieldRef != null
-                && fieldRef.DeclaringType.FullName == fullTypeName
-                && fieldRef.Name == fieldName;
-        }
-
         /// <summary>Get the method reference from an instruction if it matches.</summary>
         /// <param name="instruction">The IL instruction.</param>
         public static MethodReference AsMethodReference(Instruction instruction)

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

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Reflection;
 using Mono.Cecil;
 using Mono.Cecil.Cil;
@@ -12,54 +13,55 @@ namespace StardewModdingAPI.Framework.ModLoading.Rewriters
         /*********
         ** Fields
         *********/
-        /// <summary>The type containing the field to which references should be rewritten.</summary>
+        /// <summary>The new fields to reference indexed by the old field/type names.</summary>
-        private readonly Type Type;
+        private readonly Dictionary<string, Dictionary<string, FieldInfo>> FieldMaps = new();
-
-        /// <summary>The field name to which references should be rewritten.</summary>
-        private readonly string FromFieldName;
-
-        /// <summary>The new field to reference.</summary>
-        private readonly FieldInfo ToField;
 
 
         /*********
         ** Public methods
         *********/
         /// <summary>Construct an instance.</summary>
+        public FieldReplaceRewriter()
+            : base(defaultPhrase: "field replacement") { } // will be overridden when a field is replaced
+
+        /// <summary>Add a field to replace.</summary>
         /// <param name="fromType">The type whose field to rewrite.</param>
         /// <param name="fromFieldName">The field name to rewrite.</param>
         /// <param name="toType">The new type which will have the field.</param>
         /// <param name="toFieldName">The new field name to reference.</param>
-        public FieldReplaceRewriter(Type fromType, string fromFieldName, Type toType, string toFieldName)
+        public FieldReplaceRewriter AddField(Type fromType, string fromFieldName, Type toType, string toFieldName)
-            : base(defaultPhrase: $"{fromType.FullName}.{fromFieldName} field")
         {
-            this.Type = fromType;
+            // get full type name
-            this.FromFieldName = fromFieldName;
+            string fromTypeName = fromType?.FullName;
-            this.ToField = toType.GetField(toFieldName);
+            if (fromTypeName == null)
-            if (this.ToField == null)
+                throw new InvalidOperationException($"Can't replace field for invalid type reference {toType}.");
-                throw new InvalidOperationException($"The {toType.FullName} class doesn't have a {toFieldName} field.");
-        }
 
-        /// <summary>Construct an instance.</summary>
+            // get target field
-        /// <param name="type">The type whose field to rewrite.</param>
+            FieldInfo toField = toType.GetField(toFieldName);
-        /// <param name="fromFieldName">The field name to rewrite.</param>
+            if (toField == null)
-        /// <param name="toFieldName">The new field name to reference.</param>
+                throw new InvalidOperationException($"The {toType.FullName} class doesn't have a {toFieldName} field.");
-        public FieldReplaceRewriter(Type type, string fromFieldName, string toFieldName)
+
-            : this(type, fromFieldName, type, toFieldName)
+            // add mapping
-        {
+            if (!this.FieldMaps.TryGetValue(fromTypeName, out var fieldMap))
+                this.FieldMaps[fromTypeName] = fieldMap = new();
+            fieldMap[fromFieldName] = toField;
+
+            return this;
         }
 
         /// <inheritdoc />
         public override bool Handle(ModuleDefinition module, ILProcessor cil, Instruction instruction)
         {
-            // get field reference
             FieldReference fieldRef = RewriteHelper.AsFieldReference(instruction);
-            if (!RewriteHelper.IsFieldReferenceTo(fieldRef, this.Type.FullName, this.FromFieldName))
+            string declaringType = fieldRef?.DeclaringType?.FullName;
+
+            // get mapped field
+            if (declaringType == null || !this.FieldMaps.TryGetValue(declaringType, out var fieldMap) || !fieldMap.TryGetValue(fieldRef.Name, out FieldInfo toField))
                 return false;
 
             // replace with new field
-            instruction.Operand = module.ImportReference(this.ToField);
+            this.Phrases.Add($"{fieldRef.DeclaringType.Name}.{fieldRef.Name} field");
-
+            instruction.Operand = module.ImportReference(toField);
             return this.MarkRewritten();
         }
     }

src/SMAPI/Metadata/InstructionMetadata.cs

@@ -37,9 +37,10 @@ namespace StardewModdingAPI.Metadata
             if (rewriteMods)
             {
                 // rewrite for Stardew Valley 1.5
-                yield return new FieldReplaceRewriter(typeof(DecoratableLocation), "furniture", typeof(GameLocation), nameof(GameLocation.furniture));
+                yield return new FieldReplaceRewriter()
-                yield return new FieldReplaceRewriter(typeof(Farm), "resourceClumps", typeof(GameLocation), nameof(GameLocation.resourceClumps));
+                    .AddField(typeof(DecoratableLocation), "furniture", typeof(GameLocation), nameof(GameLocation.furniture))
-                yield return new FieldReplaceRewriter(typeof(MineShaft), "resourceClumps", typeof(GameLocation), nameof(GameLocation.resourceClumps));
+                    .AddField(typeof(Farm), "resourceClumps", typeof(GameLocation), nameof(GameLocation.resourceClumps))
+                    .AddField(typeof(MineShaft), "resourceClumps", typeof(GameLocation), nameof(GameLocation.resourceClumps));
 
                 // heuristic rewrites
                 yield return new HeuristicFieldRewriter(this.ValidateReferencesToAssemblies);
@@ -87,7 +88,7 @@ namespace StardewModdingAPI.Metadata
                         typeof(System.IO.DirectoryInfo).FullName,
                         typeof(System.IO.DriveInfo).FullName,
                         typeof(System.IO.FileSystemWatcher).FullName
-                        },
+                    },
                     InstructionHandleResult.DetectedFilesystemAccess
                 );