Reader always set OpenApiParameter.Style

[richardkaspar]

Describe the bug
Microsoft.OpenApi.Readers 1.4.1 always gives the property Style of a parameter a value.
I think it is the default value. So the information is lost that 'style' was not set in the original file.
Microsoft.OpenApi.Readers 1.3.2 works as expected. OpenApiParameter.Style has the value null.

Eventually it is an effect of resolving the bug #858

To Reproduce
Use the following code to read 'readFile' and write 'writeFile'.
Open the two files in a compare tool.
Code:

using var stream = new FileStream(readFile, FileMode.Open);
var doc =
    new OpenApiStreamReader(
            new OpenApiReaderSettings
            {
                ReferenceResolution = ReferenceResolutionSetting.DoNotResolveReferences
            })
       .Read(stream, out _);

var sb = new StringBuilder();

var writer = new OpenApiYamlWriter(new StringWriter(sb, new CultureInfo("en_us")));

doc.SerializeAsV3(writer);

File.WriteAllText(writeFile, sb.ToString());

readFile:

openapi: 3.0.1
info:
  title: magic style
  version: 1.0.0
paths: 
  /foo:
    get:
      parameters:
        - name: id
          in: query
          schema:
            type: object
            additionalProperties:
              type: integer
      responses:
        '200':
          description: foo
          content:
            text/plain:
              schema:
                type: string

writeFile:

openapi: 3.0.1
info:
  title: magic style
  version: 1.0.0
paths:
  /foo:
    get:
      parameters:
        - name: id
          in: query
          style: form
          schema:
            type: object
            additionalProperties:
              type: integer
      responses:
        '200':
          description: foo
          content:
            text/plain:
              schema:
                type: string

Expected behavior

After reading the file, the value of OpenApiParameter.Style is null.

Maybe there exists a option to switch between the two behaviours.

Screenshots/Code Snippets

Additional context

[richardkaspar]

Setting Style to null has no effect. So it is imposible to write a OpenAPI file with a parameter without 'style'.

[darrelmiller]

Thanks for reporting this. I agree this should be fixed.