System.Text.Json Source Generator with TreatWarningsAsErrors Fails

[romfir]

Description

When project is set to treat warnings as errors and XML documentation generation is enabled the build using System.Text.Json source generator fails.

Reproduction Steps

csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
    <GenerateDocumentationFile>True</GenerateDocumentationFile>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
    <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
    <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
  </PropertyGroup>

</Project>

and when I add a public class derived from JsonSerializerContext the build fails

using System.Text.Json;
using System.Text.Json.Serialization;
namespace ConsoleApp7;

/// <summary>
/// </summary>
public class Program
{
    static void Main(string[] args)
    {
        // Display the number of command line arguments.
        Console.WriteLine(args.Length);

        Person? person = new() { FirstName = "Jane", LastName = "Doe" };
        byte[] utf8Json = JsonSerializer.SerializeToUtf8Bytes(person, MyJsonContext2.Default.Person);
        person = JsonSerializer.Deserialize(utf8Json, MyJsonContext2.Default.Person);
    }
}

/// <summary>
/// </summary>
public class Person
{
    /// <summary>
    /// </summary>
    public string? FirstName { get; set; }
    /// <summary>
    /// </summary>
    public string? LastName { get; set; }
}

/// <summary>
/// 
/// </summary>
[JsonSerializable(typeof(Person))]
public partial class MyJsonContext2 : JsonSerializerContext
{
}

Expected behavior

The build should pass, one idea is to add #pragma warning disable 1591 and possibly // <auto-generated /> to generated files

Actual behavior

The build failes

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

[ghost]

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Issue Details

---

Description

When project is set to treat warnings as errors and XML documentation generation is enabled the build using System.Text.Json source generator fails.

Reproduction Steps

csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
    <GenerateDocumentationFile>True</GenerateDocumentationFile>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
    <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
    <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
  </PropertyGroup>

</Project>

and when I add a public class derived from JsonSerializerContext the build fails

using System.Text.Json;
using System.Text.Json.Serialization;
namespace ConsoleApp7;

/// <summary>
/// </summary>
public class Program
{
    static void Main(string[] args)
    {
        // Display the number of command line arguments.
        Console.WriteLine(args.Length);

        Person? person = new() { FirstName = "Jane", LastName = "Doe" };
        byte[] utf8Json = JsonSerializer.SerializeToUtf8Bytes(person, MyJsonContext2.Default.Person);
        person = JsonSerializer.Deserialize(utf8Json, MyJsonContext2.Default.Person);
    }
}

/// <summary>
/// </summary>
public class Person
{
    /// <summary>
    /// </summary>
    public string? FirstName { get; set; }
    /// <summary>
    /// </summary>
    public string? LastName { get; set; }
}

/// <summary>
/// 
/// </summary>
[JsonSerializable(typeof(Person))]
public partial class MyJsonContext2 : JsonSerializerContext
{
}

Expected behavior

The build should pass, one idea is to add #pragma warning disable 1591 and possibly // <auto-generated /> to generated files

Actual behavior

The build failes

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

Author:	romfir
Assignees:	-
Labels:	area-System.Text.Json, untriaged
Milestone:	-

[eiriktsarpalis]

Related to #61734 and #62076.

[layomia]

Dupe of #61379.