Rename type name TestEnum so that it does not end in 'Enum' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1711)

In externally visible method 'void TestEnumNewtonsoftJsonStringEnumConverter.WriteJson(JsonWriter writer, TestEnum value, JsonSerializer serializer)', validate parameter 'writer' is non-null before using it. If appropriate, throw an 'ArgumentNullException' when the argument is 'null'. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1062)

In externally visible method 'TestEnum TestEnumNewtonsoftJsonStringEnumConverter.ReadJson(JsonReader reader, Type objectType, TestEnum existingValue, bool hasExistingValue, JsonSerializer serializer)', validate parameter 'reader' is non-null before using it. If appropriate, throw an 'ArgumentNullException' when the argument is 'null'. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1062)

Call the ArgumentOutOfRangeException constructor that contains a message and/or paramName parameter (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca2208)

In externally visible method 'void TestEnumJsonStringEnumConverter.Write(Utf8JsonWriter writer, TestEnum value, JsonSerializerOptions options)', validate parameter 'writer' is non-null before using it. If appropriate, throw an 'ArgumentNullException' when the argument is 'null'. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1062)

Rename type name TestEnum so that it does not end in 'Enum' (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1711)

Call the ArgumentOutOfRangeException constructor that contains a message and/or paramName parameter (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca2208)

In externally visible method 'void TestEnumNewtonsoftJsonStringEnumConverter.WriteJson(JsonWriter writer, TestEnum value, JsonSerializer serializer)', validate parameter 'writer' is non-null before using it. If appropriate, throw an 'ArgumentNullException' when the argument is 'null'. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1062)

In externally visible method 'void TestEnumJsonStringEnumConverter.Write(Utf8JsonWriter writer, TestEnum value, JsonSerializerOptions options)', validate parameter 'writer' is non-null before using it. If appropriate, throw an 'ArgumentNullException' when the argument is 'null'. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1062)