Add support for Well Known Types

src/Protobuf.System.Text.Json/ProtobufConverter.cs

@@ -3,7 +3,9 @@
 using System.Text.Json.Serialization;
 using Google.Protobuf;
 using Google.Protobuf.Reflection;
+using Google.Protobuf.WellKnownTypes;
 using Protobuf.System.Text.Json.InternalConverters;
+using Type = System.Type;
 
 namespace Protobuf.System.Text.Json;
 
@@ -167,8 +169,24 @@ private Type GetFieldType(FieldDescriptor fieldDescriptor, Dictionary<string, Ty
                 return typeof(bool);
             case FieldType.String:
                 return typeof(string);
-            case FieldType.Message when fieldDescriptor.MessageType.ClrType != null:
-                return fieldDescriptor.MessageType.ClrType;
+            case FieldType.Message when fieldDescriptor.MessageType.ClrType is { } clrType:
+                if (clrType == typeof(DoubleValue))
+                    return typeof(double?);
+                if (clrType == typeof(FloatValue))
+                    return typeof(float?);
+                if (clrType == typeof(Int64Value))
+                    return typeof(long?);
+                if (clrType == typeof(UInt64Value))
+                    return typeof(ulong?);
+                if (clrType == typeof(Int32Value))
+                    return typeof(int?);
+                if (clrType == typeof(UInt32Value))
+                    return typeof(uint?);
+                if (clrType == typeof(BoolValue))
+                    return typeof(bool?);
+                if (clrType == typeof(StringValue))
+                    return typeof(string);
+                return clrType;
             case FieldType.Enum when fieldDescriptor.IsRepeated:
                 var fieldType = propertyTypeLookup[fieldDescriptor.PropertyName];
                 return fieldType.GenericTypeArguments[0];

test/Protobuf.System.Text.Json.Tests/MessageWithWellKnownTypesTests.Should_serialize_message_with_well_known_types_when_values_are_not_set.approved.json

@@ -0,0 +1,10 @@
+{
+  "doubleValue": null,
+  "floatValue": null,
+  "int64Value": null,
+  "uint64Value": null,
+  "int32Value": null,
+  "uint32Value": null,
+  "boolValue": null,
+  "stringValue": null
+}

test/Protobuf.System.Text.Json.Tests/MessageWithWellKnownTypesTests.Should_serialize_message_with_well_known_types_when_values_are_set.approved.json

@@ -0,0 +1,10 @@
+{
+  "doubleValue": 1.7976931348623157E+308,
+  "floatValue": 3.4028235E+38,
+  "int64Value": 9223372036854775807,
+  "uint64Value": 18446744073709551615,
+  "int32Value": 2147483647,
+  "uint32Value": 4294967295,
+  "boolValue": true,
+  "stringValue": "some_string_value"
+}

test/Protobuf.System.Text.Json.Tests/MessageWithWellKnownTypesTests.cs

@@ -0,0 +1,94 @@
+using System.Text.Json;
+using System.Text.Json.Protobuf.Tests;
+using System.Text.Json.Serialization;
+using Protobuf.System.Text.Json.Tests.Utils;
+using Shouldly;
+using SmartAnalyzers.ApprovalTestsExtensions;
+using Xunit;
+
+namespace Protobuf.System.Text.Json.Tests;
+
+public class MessageWithWellKnownTypesTests
+{
+    [Fact]
+    public void Should_serialize_message_with_well_known_types_when_values_are_set()
+    {
+        // Arrange
+        var msg = new MessageWithWellKnownTypes
+        {
+            DoubleValue = double.MaxValue,
+            FloatValue = float.MaxValue,
+            Int64Value = long.MaxValue,
+            Uint64Value = ulong.MaxValue,
+            Int32Value = int.MaxValue,
+            Uint32Value = uint.MaxValue,
+            BoolValue = true,
+            StringValue = "some_string_value",
+        };
+        var jsonSerializerOptions = TestHelper.CreateJsonSerializerOptions();
+
+        // Act
+        var serialized = JsonSerializer.Serialize(msg, jsonSerializerOptions);
+
+        // Assert
+        var approver = new ExplicitApprover();
+        approver.VerifyJson(serialized);
+    }
+
+    [Fact]
+    public void Should_serialize_message_with_well_known_types_when_values_are_not_set()
+    {
+        // Arrange
+        var msg = new MessageWithWellKnownTypes();
+        var jsonSerializerOptions = TestHelper.CreateJsonSerializerOptions();
+        jsonSerializerOptions.DefaultIgnoreCondition = JsonIgnoreCondition.Never;
+
+        // Act
+        var serialized = JsonSerializer.Serialize(msg, jsonSerializerOptions);
+
+        // Assert
+        var approver = new ExplicitApprover();
+        approver.VerifyJson(serialized);
+    }
+
+    [Fact]
+    public void Should_serialize_and_deserialize_message_with_well_known_types_when_values_are_set()
+    {
+        // Arrange
+        var msg = new MessageWithWellKnownTypes
+        {
+            DoubleValue = double.MaxValue,
+            FloatValue = float.MaxValue,
+            Int64Value = long.MaxValue,
+            Uint64Value = ulong.MaxValue,
+            Int32Value = int.MaxValue,
+            Uint32Value = uint.MaxValue,
+            BoolValue = true,
+            StringValue = "some_string_value"
+        };
+        var jsonSerializerOptions = TestHelper.CreateJsonSerializerOptions();
+        var serialized = JsonSerializer.Serialize(msg, jsonSerializerOptions);
+
+        // Act
+        var deserialized = JsonSerializer.Deserialize<MessageWithWellKnownTypes>(serialized, jsonSerializerOptions);
+
+
+        // Assert
+        deserialized.ShouldBe(msg);
+    }
+
+    [Fact]
+    public void Should_serialize_and_deserialize_message_with_well_known_types_when_values_are_not_set()
+    {
+        // Arrange
+        var msg = new MessageWithWellKnownTypes();
+        var jsonSerializerOptions = TestHelper.CreateJsonSerializerOptions();
+        var serialized = JsonSerializer.Serialize(msg, jsonSerializerOptions);
+
+        // Act
+        var deserialized = JsonSerializer.Deserialize<MessageWithWellKnownTypes>(serialized, jsonSerializerOptions);
+
+        // Assert
+        deserialized.ShouldBe(msg);
+    }
+}

test/Protobuf.System.Text.Json.Tests/Protos/message_with_well_known_types.proto

@@ -0,0 +1,23 @@
+syntax = "proto3";
+
+option csharp_namespace = "System.Text.Json.Protobuf.Tests";
+
+import "google/protobuf/wrappers.proto";
+
+message MessageWithWellKnownTypes {
+  google.protobuf.DoubleValue double_value = 1;
+
+  google.protobuf.FloatValue float_value = 2;
+
+  google.protobuf.Int64Value int_64_value = 3;
+
+  google.protobuf.UInt64Value uint_64_value = 4;
+
+  google.protobuf.Int32Value int_32_Value = 5;
+
+  google.protobuf.UInt32Value uint_32_Value = 6;
+
+  google.protobuf.BoolValue bool_value = 7;
+
+  google.protobuf.StringValue string_value = 8;
+}