Added ValueTuple support

fix #129

src/Dahomey.Cbor.Tests/TupleTests.cs

@@ -0,0 +1,63 @@
+using Xunit;
+
+namespace Dahomey.Cbor.Tests
+{
+    public class TupleTests
+    {
+        [Fact]
+        public void ReadTuple()
+        {
+            const string hexBuffer = "82664C6F6E646F6E1907E7"; //["London", 2023]
+            (string stringValue, int intValue) = Helper.Read<(string, int)>(hexBuffer);
+
+            Assert.Equal("London", stringValue);
+            Assert.Equal(2023, intValue);
+        }
+
+        [Fact]
+        public void WriteTuple()
+        {
+            const string hexBuffer = "82664C6F6E646F6E1907E7"; //["London", 2023]
+            string hexResult = Helper.Write(("London", 2023));
+
+            Assert.Equal(hexBuffer, hexResult);
+        }
+
+        public class TupleObject
+        {
+            public int Int { get; set; }
+            public (int, string) Tuple { get; set; }
+            public string String { get; set; }
+        }
+
+        [Fact]
+        public void ReadTupleObject()
+        {
+            // {"Int":12, "Tuple":[12, "foo"], "String": "foo"}
+            const string hexBuffer = "A363496E740C655475706C65820C63666F6F66537472696E6763666F6F";
+
+            TupleObject obj = Helper.Read<TupleObject>(hexBuffer);
+            Assert.NotNull(obj);
+            Assert.Equal(12, obj.Int);
+            Assert.Equal(12, obj.Tuple.Item1);
+            Assert.Equal("foo", obj.Tuple.Item2);
+            Assert.Equal("foo", obj.String);
+        }
+
+        [Fact]
+        public void WriteTupleObject()
+        {
+            // {"Int":12, "Tuple":[12, "foo"], "String": "foo"}
+            const string hexBuffer = "A363496E740C655475706C65820C63666F6F66537472696E6763666F6F";
+
+            TupleObject obj = new TupleObject
+            {
+                Int = 12,
+                Tuple = (12, "foo"),
+                String = "foo",
+            };
+
+            Helper.TestWrite(obj, hexBuffer);
+        }
+    }
+}

src/Dahomey.Cbor/Serialization/Converters/CborConverterRegistry.cs

@@ -17,6 +17,7 @@ public CborConverterRegistry(CborOptions options)
 
             // order matters. It's in reverse order of how they'll get consumed
             RegisterConverterProvider(new ObjectConverterProvider());
+            RegisterConverterProvider(new TupleConverterProvider());
             RegisterConverterProvider(new CollectionConverterProvider());
             RegisterConverterProvider(new PrimitiveConverterProvider());
             RegisterConverterProvider(new ByAttributeConverterProvider());

src/Dahomey.Cbor/Serialization/Converters/Providers/TupleConverterProvider.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+
+namespace Dahomey.Cbor.Serialization.Converters.Providers
+{
+    public class TupleConverterProvider : CborConverterProviderBase
+    {
+        private static readonly HashSet<Type> ValueTupleTypes = new HashSet<Type>(
+        [
+            typeof(ValueTuple<>),
+            typeof(ValueTuple<,>),
+            typeof(ValueTuple<,,>),
+            typeof(ValueTuple<,,,>),
+            typeof(ValueTuple<,,,,>),
+            typeof(ValueTuple<,,,,,>),
+            typeof(ValueTuple<,,,,,,>),
+            typeof(ValueTuple<,,,,,,,>)
+        ]);
+
+        public override ICborConverter? GetConverter(Type type, CborOptions options)
+        {
+            if (type.IsGenericType && ValueTupleTypes.Contains(type.GetGenericTypeDefinition()))
+            {
+                FieldInfo[] fields = type.GetFields();
+                switch (fields.Length)
+                {
+                    case 2:
+                        return CreateGenericConverter(options, typeof(Tuple2Converter<,>), fields.Select(field => field.FieldType).ToArray());
+
+                    case 3:
+                        return CreateGenericConverter(options, typeof(Tuple3Converter<,,>), fields.Select(field => field.FieldType).ToArray());
+
+                    case 4:
+                        return CreateGenericConverter(options, typeof(Tuple4Converter<,,,>), fields.Select(field => field.FieldType).ToArray());
+
+                    case 5:
+                        return CreateGenericConverter(options, typeof(Tuple5Converter<,,,,>), fields.Select(field => field.FieldType).ToArray());
+
+                    case 6:
+                        return CreateGenericConverter(options, typeof(Tuple6Converter<,,,,,>), fields.Select(field => field.FieldType).ToArray());
+
+                    case 7:
+                        return CreateGenericConverter(options, typeof(Tuple7Converter<,,,,,,>), fields.Select(field => field.FieldType).ToArray());
+
+                    case 8:
+                        return CreateGenericConverter(options, typeof(Tuple8Converter<,,,,,,,>), fields.Select(field => field.FieldType).ToArray());
+
+                    default:
+                        throw new CborException($"Tuples of length {fields.Length} are not supported");
+                }
+            }
+
+            return null;
+        }
+    }
+}