JsonSourceGenerationOptionsAttribute constructor is out of sync with the JsonSerializerOptions constructor

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Description

As the title suggests, JsonSourceGenerationOptionsAttribute(JsonSerializerDefaults defaults) is out of sync with JsonSerializerOptions(JsonSerializerDefaults defaults), despite the comment suggesting otherwise.
This leads to an ArgumentOutOfRangeException when the type is annotated with [JsonSourceGenerationOptionsAttribute(JsonSerializerDefaults.Strict)].

Reproduction Steps

using System.Text.Json;
using System.Text.Json.Serialization;

internal static class Reproduction
{
    public static void Main()
    {
        // Crash at runtime
        _ = typeof(SourceGenerationContext).GetCustomAttributes(true);
    }
}

[JsonSourceGenerationOptions(JsonSerializerDefaults.Strict)]
[JsonSerializable(typeof(Example))]
internal partial class SourceGenerationContext : JsonSerializerContext;

internal class Example;

Expected behavior

The returned array contains the JsonSourceGenerationOptions attribute with its properties configured analogously to a new JsonSerializerOptions(JsonSerializerDefaults.Strict).

Actual behavior

The program crashes with the following message, despite the enum value being valid:

System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values. (Parameter 'defaults')

Regression?

No

Known Workarounds

Assign the attribute properties manually, referencing the JsonSerializerOptions(JsonSerializerDefaults defaults) constructor.

Configuration

• .NET 10.0.101
• Windows 11 24H2 (build 26100.7462)
• x64 architecture

The issue is specific to versions of .NET 10 past and including .NET 10 Preview 6.

Other information

The JsonSerializerDefaults.Strict enum value was implemented by #116271. The lack of support in the JsonSourceGenerationOptionsAttribute is likely an oversight.

Relevant code

runtime/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/JsonSerializerOptions.cs

Lines 170 to 191 in 2c8bf45

	public JsonSerializerOptions(JsonSerializerDefaults defaults) : this()
	{
	// Should be kept in sync with equivalent overload in JsonSourceGenerationOptionsAttribute
	if (defaults == JsonSerializerDefaults.Web)
	{
	_propertyNameCaseInsensitive = true;
	_jsonPropertyNamingPolicy = JsonNamingPolicy.CamelCase;
	_numberHandling = JsonNumberHandling.AllowReadingFromString;
	}
	else if (defaults == JsonSerializerDefaults.Strict)
	{
	_unmappedMemberHandling = JsonUnmappedMemberHandling.Disallow;
	_allowDuplicateProperties = false;
	_respectNullableAnnotations = true;
	_respectRequiredConstructorParameters = true;
	}
	else if (defaults != JsonSerializerDefaults.General)
	{
	throw new ArgumentOutOfRangeException(nameof(defaults));
	}
	}

runtime/src/libraries/System.Text.Json/Common/JsonSourceGenerationOptionsAttribute.cs

Lines 27 to 41 in 84d9854

	public JsonSourceGenerationOptionsAttribute(JsonSerializerDefaults defaults)
	{
	// Constructor kept in sync with equivalent overload in JsonSerializerOptions
	if (defaults is JsonSerializerDefaults.Web)
	{
	PropertyNameCaseInsensitive = true;
	PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase;
	NumberHandling = JsonNumberHandling.AllowReadingFromString;
	}
	else if (defaults is not JsonSerializerDefaults.General)
	{
	throw new ArgumentOutOfRangeException(nameof(defaults));
	}
	}

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