[BUG][Rust] Fields that should be nullable aren't Option

[tecywiz121]

Description

The Rust generator output String when I think it should have output Option<String> in the model.

openapi-generator version

4.0.0-beta2

OpenAPI declaration file content or url

openapi: "3.0.0"
info:
  version: 0.0.0
  title: Bug Report
paths:
  /:
    get:
      responses:
        '200':
          description: ""
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Pages"
components:
  schemas:
    Pages:
      required:
        - next
      properties:
        next:
          type: string
          nullable: true

Command line used for generation

openapi-generator generate -i bug-report.yml -g rust -o bug-report

Steps to reproduce

Generate the client library.

Related issues/PRs

#2269
#1766

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[wing328]

What about using the {{#isNullable}}...{{/isNullable}} mustache tag to to include Option<...>??

[tecywiz121]

Something like that?

[wing328]

Yup, that should work as we've implemented it in other generators. Let us know if you need help filing a PR. Thanks for your contribution.