Inconsistent sorting criteria object (Pageable's sort)

[jernejcvek]

Bug description
Pageable holds inconsistent sort object of type List<String>. Please see the following examples:

• query parameter: ?sort=id, sort object: ["id"], size of the object: 1
• query parameter: ?sort=id,desc, sort object: ["id", "desc"], size of the object: 2
• query parameter: ?sort=id,desc&sort=name, sort object: ["id,desc", "name"], size of the object: 2
• query parameter: ?sort=id,desc&sort=name,desc, sort object: ["id,desc", "name,desc"], size of the object: 2
• query parameter: ?sort=id,desc&sort=name,desc&sort=address, sort object: ["id,desc", "name,desc", "address"], size of the object: 3
• query parameter: ?sort=id,desc&sort=name,desc&sort=address,desc, sort object: ["id,desc", "name,desc", "address,desc"], size of the object: 3

Versions and usage

• Spring Boot 2.2.2
• springdoc-openapi-ui & springdoc-openapi-data-rest: 1.4.8
• Controller's method is annotated with @PageableAsQueryParam, with hidden method's parameter: @Parameter(hidden = true) Pageable pageable so that pagination and sorting criteria are properly shown in the UI:
  
• Example of Swagger UI's generated request URL for the problematic case: ...&page=0&size=20&sort=id%2Cdesc

Expected behaviour

• When the query parameter is sort=id,desc (bolded example above) the Pageable's sort object should contain only one element ["id,desc"].

[bnasslahsen]

@jernejcvek,

Not sure what issue you are pointing out here.
Anyway, this doesn't seem related to the OpenAPI spec, which is generated by the springdoc-openapi.

If you think, there is any issue, please make sure all the information described in the contribution guide.

If you are having issues with the UI. You can have at the swagger-ui project instead.