Description
Source generated JSON deserialization fails with JsonExtensionData property using init accessor:
using System.Text.Json.Serialization;
using System.Text.Json;
string json = "{\"Value\":42,\"OverflowValue\":\"42\"}";
Demo demo = JsonSerializer.Deserialize(json, DemoContext.Default.Demo)!;
string roundtrip = JsonSerializer.Serialize(demo, DemoContext.Default.Demo);
Console.WriteLine(string.Equals(json, roundtrip, StringComparison.Ordinal));
public sealed class Demo
{
public int Value { get; init; }
[JsonExtensionData]
public Dictionary<string, JsonElement>? ExtensionData { get; init; }
}
[JsonSourceGenerationOptions(GenerationMode = JsonSourceGenerationMode.Metadata)]
[JsonSerializable(typeof(Demo))]
public sealed partial class DemoContext : JsonSerializerContext { }Reproduction Steps
- Create console application from template with the sample code above
- Run application
Expected behavior
Application completes with no significant problems and prints "True".
Actual behavior
Application throws exception:
Unhandled exception. System.InvalidOperationException: The extension data property 'ExtensionData' on type 'Demo' cannot bind with a parameter in the deserialization constructor.
at System.Text.Json.ThrowHelper.ThrowInvalidOperationException_ExtensionDataCannotBindToCtorParam(String propertyName, JsonPropertyInfo jsonPropertyInfo)
at System.Text.Json.Serialization.Metadata.JsonTypeInfo.ConfigureConstructorParameters()
at System.Text.Json.Serialization.Metadata.JsonTypeInfo.Configure()
at System.Text.Json.Serialization.Metadata.JsonTypeInfo.<EnsureConfigured>g__ConfigureSynchronized|172_0()
at System.Text.Json.JsonSerializerOptions.GetTypeInfoInternal(Type type, Boolean ensureConfigured, Nullable`1 ensureNotNull, Boolean resolveIfMutable, Boolean fallBackToNearestAncestorType)
at System.Text.Json.JsonSerializerOptions.GetTypeInfo(Type type)
at DemoContext.get_Demo() in D:\repos\SourceGenJsonDemo\SourceGenJsonDemo\obj\Debug\net8.0\System.Text.Json.SourceGeneration\System.Text.Json.SourceGeneration.JsonSourceGenerator\DemoContext.Demo.g.cs:line 18
at Program.<Main>$(String[] args) in D:\repos\SourceGenJsonDemo\SourceGenJsonDemo\Program.cs:line 5
Regression?
Probably not: init property deserialization is not supported by System.Text.Json in previous .NET versions.
Known Workarounds
Change the overflow property to use a public or internal set accessor.
Configuration
.NET info:
.NET SDK:
Version: 9.0.100-rc.1.24452.12
Commit: 81a714c6d3
Workload version: 9.0.100-manifests.67cd1eb6
MSBuild version: 17.12.0-preview-24422-09+d17ec720d
Runtime Environment:
OS Name: Windows
OS Version: 10.0.22635
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\9.0.100-rc.1.24452.12\
.NET workloads installed:
Configured to use loose manifests when installing new manifests.
[aspire]
Installation Source: VS 17.11.35303.130, VS 17.12.35309.182
Manifest Version: 8.2.0/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.aspire\8.2.0\WorkloadManifest.json
Install Type: FileBased
Host:
Version: 9.0.0-rc.1.24431.7
Architecture: x64
Commit: static
.NET SDKs installed:
8.0.304 [C:\Program Files\dotnet\sdk]
8.0.400 [C:\Program Files\dotnet\sdk]
8.0.401 [C:\Program Files\dotnet\sdk]
9.0.100-rc.1.24452.12 [C:\Program Files\dotnet\sdk]
.NET runtimes installed:
Microsoft.AspNetCore.App 6.0.33 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.0-rc.1.24452.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 6.0.33 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.0-rc.1.24431.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 6.0.33 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.8 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.0-rc.1.24452.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]
Environment variables:
Not set
global.json file:
Not found
Project configuration:
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net8.0</TargetFramework>
<ImplicitUsings>enable</ImplicitUsings>
<Nullable>enable</Nullable>
</PropertyGroup>
<ItemGroup>
<PackageReference Include="System.Text.Json" Version="8.0.4" />
</ItemGroup>
</Project>
Other information
No response
Description
Source generated JSON deserialization fails with
JsonExtensionDataproperty usinginitaccessor:Reproduction Steps
Expected behavior
Application completes with no significant problems and prints "True".
Actual behavior
Application throws exception:
Regression?
Probably not:
initproperty deserialization is not supported by System.Text.Json in previous .NET versions.Known Workarounds
Change the overflow property to use a public or internal set accessor.
Configuration
.NET info:
Project configuration:
Other information
No response