improperly handles optional``` requestBody```

[KotoriK]

For example a typescript definition file generated by openapi-typescript:

export interface paths{
  '/api/auth/login': {
    post: {
      requestBody?: {
        content: {
          'application/json': components['schemas']['LoginInput'];
          'text/json': components['schemas']['LoginInput'];
          'application/*+json': components['schemas']['LoginInput'];
        };
      };
      responses: {
        /** @description Success */
        200: never;
      };
    };
  };
}

In this case, below code will throw a type error, indicating body should be undefined:

createFetch<paths>('/api/auth/login',{body:{name:string}})

after changing requestBody to required, body can be infered correctly.

Expecting behaviour

optional requestBody should be infer as ${RequestBodySchema} | undefined instead of undefined

Reproduce link

https://codesandbox.io/s/openapi-fetch-optional-requestbody-8e699k

it cannot be compiled in browser because of some typescript issue, please download and setup on local.

[drwpow]

Can confirm this is happening. Omitting the body works, but providing it raises a TS error. Will work on a fix