Add Adapt extensions with temporary TypeAdapterConfig and TypeAdapter…

src/Mapster.Tests/WhenUseTempAdapterConfig.cs

@@ -0,0 +1,75 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Shouldly;
+
+namespace Mapster.Tests
+{
+
+    public record SourceDto(string Name, int Age);
+    public record DestinationDto(long Id, string Name, int Age);
+
+    [TestClass]
+    public class WhenUseTempAdapterConfig
+    {
+        [TestMethod]
+        public void Adapt_TemporaryConfig_ShouldMapInitOnlyProperties()
+        {
+            // Arrange
+            var source = new SourceDto("Alice", 30);
+            long id = 42;
+
+            // Act
+            var result = source.Adapt<DestinationDto>(cfg =>
+            {
+                cfg.NewConfig<SourceDto, DestinationDto>()
+                   .Map(dest => dest.Id, src => id);
+            });
+
+            // Assert
+            result.Name.ShouldBe("Alice");
+            result.Age.ShouldBe(30);
+            result.Id.ShouldBe(42);
+        }
+
+        [TestMethod]
+        public void Adapt_WithSetter_ShouldMapInitOnlyProperties()
+        {
+            // Arrange
+            var source = new SourceDto("Bob", 25);
+            long id = 99;
+
+            // Act
+            var result = source.Adapt<SourceDto, DestinationDto>(setter =>
+            {
+                setter.Map(dest => dest.Id, src => id);
+            });
+
+            // Assert
+            result.Name.ShouldBe("Bob");
+            result.Age.ShouldBe(25);
+            result.Id.ShouldBe(99);
+        }
+
+        [TestMethod]
+        public void Adapt_TemporaryConfig_ShouldNotModifyGlobalSettings()
+        {
+            // Arrange
+            var source = new SourceDto("Charlie", 40);
+            long id = 123;
+
+            var globalMap = TypeAdapterConfig.GlobalSettings.GetMapFunction<SourceDto, DestinationDto>();
+
+            // Act
+            var result = source.Adapt<SourceDto, DestinationDto>(setter =>
+            {
+                setter.Map(dest => dest.Id, src => id);
+            });
+
+            // Assert
+            var original = globalMap(source); // mapping via GlobalSettings
+            original.Id.ShouldBe(default(long)); // GlobalSettings unaffected
+            original.Name.ShouldBe("Charlie");
+            original.Age.ShouldBe(40);
+        }
+
+    }
+}

src/Mapster/TypeAdapter.cs

@@ -263,6 +263,42 @@ public static TDestination ValidateAndAdapt<TSource, TDestination>(this TSource
             }
             return source.Adapt<TDestination>(config);
         }
+
+
+        /// <summary>
+        /// Adapt the source object to a destination type using a temporary configuration.
+        /// A new TypeAdapterConfig is created for this call, ensuring GlobalSettings remain unchanged.
+        /// Safe for init-only properties and record types.
+        /// </summary>
+        /// <typeparam name="TDestination">Destination type.</typeparam>
+        /// <param name="source">Source object to adapt.</param>
+        /// <param name="configAction">Action to customize the temporary config.</param>
+        /// <returns>Adapted destination object of type TDestination.</returns>
+        public static TDestination Adapt<TDestination>(this object? source, Action<TypeAdapterConfig> configAction)
+        {
+            var config = TypeAdapterConfig.GlobalSettings.Clone();
+            configAction(config);
+            return source.Adapt<TDestination>(config);
+        }
+
+        /// <summary>
+        /// Adapt the source object from TSource to TDestination using a dedicated TypeAdapterSetter.
+        /// A temporary TypeAdapterConfig is created and configured via the setter.
+        /// Safe for init-only properties and record types, without modifying GlobalSettings.
+        /// </summary>
+        /// <typeparam name="TSource">Source type.</typeparam>
+        /// <typeparam name="TDestination">Destination type.</typeparam>
+        /// <param name="source">Source object to adapt.</param>
+        /// <param name="configAction">Action to customize the TypeAdapterSetter.</param>
+        /// <returns>Adapted destination object of type TDestination.</returns>
+        public static TDestination Adapt<TSource, TDestination>(this object? source, Action<TypeAdapterSetter<TSource, TDestination>> configAction)
+        {
+            var config = TypeAdapterConfig.GlobalSettings.Clone();
+            var setter = config.ForType<TSource, TDestination>();
+            configAction(setter);
+            setter.Settings.Resolvers.Reverse();
+            return source.Adapt<TDestination>(config);
+        }
     }
 
     [System.Diagnostics.CodeAnalysis.SuppressMessage("Minor Code Smell", "S1104:Fields should not have public accessibility", Justification = "<Pending>")]