[BUG][DART] Method listFromJson isn't defined on array of enums

[selankon]

Description

When I define inside an object a property that is an array of enums, the generated code call a method listFromJson that is not defined inside the enum model causing build problems.

openapi-generator version

➜ openapi-generator version
4.2.2

OpenAPI declaration file content or url

openapi: 3.0.0
info:
    title: RetroShare OpenApi wrapper
    version: 0.0.1
    description: RetroShare OpenApi wrapper generated using Doxygen documentation
    license:
        name: AGPLv3
servers:
    - url: http://127.0.0.1:9092/
    
paths:
    /jsonApiServer/version:
        post:
            summary: blahblah             
            responses:
                '200':
                    description: >
                            return: 
                    content:
                        application/json:
                            schema:
                                $ref: '#/components/schemas/FileChunksInfo'

components:      
    schemas:
        FileChunksInfo:
            type: object
            properties:
                chunks:
                    type: array
                    items:
                        $ref: '#/components/schemas/ChunkState'
        ChunkState:
            type: integer
            enum:
                
                    - 0
                    - 1
                    - 2
                    - 3
            x-enum-varnames:
                
                    - CHUNK_OUTSTANDING
                    - CHUNK_ACTIVE
                    - CHUNK_DONE
                    - CHUNK_CHECKING

Command line used for generation

➜ openapi-generator generate -i definition.yml -g dart -o openapi-dart-retroshare-api-wrapper

Steps to reproduce

Just copy the .yml definition and run the command.

After the code is generated be sure that all the dependencies are installed. I us VSCodium with Dart extension for that.

Once all installed you will see a build error on lib/model/file_chunks_info.dart.

  FileChunksInfo.fromJson(Map<String, dynamic> json) {
    if (json == null) return;
    chunks = (json['chunks'] == null) ?
      null :
      ChunkState.listFromJson(json['chunks']);
  }

Where listFromJson is not defined on ChunkState model.

Related issues/PRs

Maybe related to #2567

Suggest a fix

Should the nums have the method listFromJson?

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[kuhnroyal]

Also running into this.

[selankon]

The method that is not implemented and is implemented on other models should be like:

static List<ChunkState> listFromJson(List<dynamic> json) {
    return json == null ? List<ChunkState>() : json.map((value) => ChunkState.fromJson(value)).toList();
  }

I'm not sure why this is not implemented, but looking at the mustache files dart/class.mustache I found:

  static List<{{classname}}> listFromJson(List<dynamic> json) {
    return json == null ? new List<{{classname}}>() : json.map((value) => new {{classname}}.fromJson(value)).toList();
  }

So maybe we need only to add this code on dart/enum.mustache ? Something like that (i'm not able to do the checklist to make a PR right now...)

[selankon]

I created the PR but modifying the template inside dart2 folder.

[tuomohopia]

I keep hitting this myself too. Any good ways to solve this?

[selankon]

Please merge my PR (is not merged on master yet)
#5355

[wing328]

@selankon thanks for the fix, which has been merged into the master.

Have a nice weekend.