Description
If using a subtype of JsonConverterAttribute which overrides the CreateConverter method but has no constructor parameters, JsonSourceGenerator.Parser.cs#L1234 produces an IndexOutOfRangeException instead of failing with an error diagnostic, which leads to errors involving unimplemented abstracts rather than expected information on the actual source of the error.
Reproduction Steps
public class MyJsonConverterAttribute : JsonConverterAttribute {
public override JsonConverter? CreateConverter(Type typeToConvert) => null; // actual converter logic would go here
}
public class MyType {
[MyJsonConverter]
public int Foo { get; init; }
}
[JsonSerializable(typeof(MyType))]
public partial class MyJsonContext : JsonSerializerContext;Expected behavior
An error diagnostic on the attribute usage.
Actual behavior
Several unimplemented abstract method errors on the context class declaration and no generated code.
Regression?
No response
Known Workarounds
Using a JsonConverterFactory implementation with the default JsonConverterAttribute sidesteps the issue neatly while also just working rather than being a compiler error, but with third party libraries that may not be easy or possible.
Configuration
.net 8 preview; I do not believe it to be specific to that configuration.
Other information
Related issue: nodatime.serialization#97
Description
If using a subtype of
JsonConverterAttributewhich overrides theCreateConvertermethod but has no constructor parameters, JsonSourceGenerator.Parser.cs#L1234 produces anIndexOutOfRangeExceptioninstead of failing with an error diagnostic, which leads to errors involving unimplemented abstracts rather than expected information on the actual source of the error.Reproduction Steps
Expected behavior
An error diagnostic on the attribute usage.
Actual behavior
Several unimplemented abstract method errors on the context class declaration and no generated code.
Regression?
No response
Known Workarounds
Using a
JsonConverterFactoryimplementation with the defaultJsonConverterAttributesidesteps the issue neatly while also just working rather than being a compiler error, but with third party libraries that may not be easy or possible.Configuration
.net 8 preview; I do not believe it to be specific to that configuration.
Other information
Related issue: nodatime.serialization#97