[DebuggerDisplay] for JsonTypeInfo does not render

[martincostello]

Description

While debugging some code using the JSON source generator in Visual Studio 2022 I found that the debugger display for a JsonSerializerContext class is broken.

Instead of showing the intended display text, instead the IDE shows a message similar to ConverterStrategy.error CS0119: 'ConverterStrategy' is a type, which is not valid in the given context, "Boolean".

Following the code through, it looks like there's an issue with the value passed to the constructor of the [DebuggerDisplay] attribute on JsonTypeInfo here:

runtime/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs

Line 17 in c41f452

[DebuggerDisplay("ConverterStrategy.{ConverterStrategy}, {Type.Name}")]

Reproduction Steps

View a derived instance of `` using the JSON source generator in an IDE with Intellisense, such as Visual Studio 2022.

using System.Text.Json.Serialization;

var context = new CustomJsonSerializerContext();

// Put a breakpoint on the line below and inspect context in the debugger
Console.ReadLine();

[JsonSerializable(typeof(bool))]
internal sealed partial class CustomJsonSerializerContext : JsonSerializerContext
{
}

Expected behavior

A compiler error is not shown in the rendered debugger display for the class' properties.

Actual behavior

The properties all show a compiler error similar to the below.

ConverterStrategy.error CS0119: 'ConverterStrategy' is a type, which is not valid in the given context, "Boolean".

Regression?

No, this functionality was new in .NET 6.

Known Workarounds

None.

Configuration

> dotnet --info
.NET SDK (reflecting any global.json):
 Version:   6.0.200
 Commit:    4c30de7899

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.22000
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\6.0.200\

Other information

No response

[ghost]

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Issue Details

---

Description

While debugging some code using the JSON source generator in Visual Studio 2022 I found that the debugger display for a JsonSerializerContext class is broken.

Instead of showing the intended display text, instead the IDE shows a message similar to ConverterStrategy.error CS0119: 'ConverterStrategy' is a type, which is not valid in the given context, "Boolean".

Following the code through, it looks like there's an issue with the value passed to the constructor of the [DebuggerDisplay] attribute on JsonTypeInfo here:

runtime/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs

Line 17 in c41f452

[DebuggerDisplay("ConverterStrategy.{ConverterStrategy}, {Type.Name}")]

Reproduction Steps

View a derived instance of `` using the JSON source generator in an IDE with Intellisense, such as Visual Studio 2022.

using System.Text.Json.Serialization;

var context = new CustomJsonSerializerContext();

// Put a breakpoint on the line below and inspect context in the debugger
Console.ReadLine();

[JsonSerializable(typeof(bool))]
internal sealed partial class CustomJsonSerializerContext : JsonSerializerContext
{
}

Expected behavior

A compiler error is not shown in the rendered debugger display for the class' properties.

Actual behavior

The properties all show a compiler error similar to the below.

ConverterStrategy.error CS0119: 'ConverterStrategy' is a type, which is not valid in the given context, "Boolean".

Regression?

No, this functionality was new in .NET 6.

Known Workarounds

None.

Configuration

> dotnet --info
.NET SDK (reflecting any global.json):
 Version:   6.0.200
 Commit:    4c30de7899

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.22000
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\6.0.200\

Other information

No response

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

[eiriktsarpalis]

Thanks, I've been seeing this as well. It seems to be impacting a few internal serializer types as well. I submitted a fix in #65971