[Bug]: When using NonNullableReferenceTypesAsRequired, both required and nullable exist

[LiuYuLu]

Describe the bug

Expected behavior

Remove the summary field "nullable": true configuration

Actual behavior

No response

Steps to reproduce

No response

Exception(s) (if any)

Use the net9 default webapi template
Add or modify the following configuration

builder.Services.AddSwaggerGen(c => c.NonNullableReferenceTypesAsRequired());

app.UseSwagger();
app.UseSwaggerUI();

Remove the ? in front of the Summary attribute.

public class WeatherForecast
{
    public string Summary { get; set; }
}

Swashbuckle.AspNetCore version

7.3.1

.NET Version

net9

Anything else?

No response

[rdehouss]

I can reproduce with version 8.0.0 also, .net9

    builder.Services.AddSwaggerGen(options => {
      options.SchemaGeneratorOptions.NonNullableReferenceTypesAsRequired = false;
    });

does not change anything BTW, true or false, there are the nullables while required

[Focus1337]

Maybe I misunderstand the problem. Try using the SupportNullableReferenceTypes() option together with NonNullableReferenceTypesAsRequired(). In this case, everything seems to be generated as expected.

Reproduced:
.NET 8
Swashbuckle.AspNetCore 7.3.1

Model:

public class WeatherForecast
{
    public string Summary { get; set; }
    public string? NullableSummary { get; set; }
}

options:

    o.SupportNonNullableReferenceTypes();
    o.NonNullableReferenceTypesAsRequired();

json:

  "components": {
    "schemas": {
      "WeatherForecast": {
        "required": [
          "date",
          "summary",
          "temperatureC",
          "temperatureF"
        ],
        "type": "object",
        "properties": {
          "date": {
            "type": "string",
            "format": "date"
          },
          "temperatureC": {
            "type": "integer",
            "format": "int32"
          },
          "temperatureF": {
            "type": "integer",
            "format": "int32",
            "readOnly": true
          },
          "summary": {
            "type": "string"
          },
          "nullableSummary": {
            "type": "string",
            "nullable": true
          }
        },
        "additionalProperties": false
      }
    }

[Focus1337]

If this is solution, I think the problem is that there is no contract anywhere that says that SupportNonNullableReferenceTypes needs to be enabled for NonNullableReferenceTypesAsRequired to work properly