Global type name uniqueness constraint too onerous

[Elvecent]

Due to how Monoid instances for hashmaps work, the final API description contains exact same schemas for different types with the same name.

This is a bug unless it is required that type names are globally unique. However, it should be possible to lift this requirement by disambiguating hashmap keys, i. e. by adding route name as a prefix to each key.

Alternatively, I'd like there to be a warning or even an error, because otherwise I simply end up with wrong documentation.

Example:

-- in Module1.hs
data ResponseBody = ResponseBody { rbField1 :: () } deriving Generic

-- in Module2.hs
data ResponseBody = ResponseBody { rbField2 :: () } deriving Generic

-- in Main.hs
type MyApi
  = "Route1" :> Get '[JSON] Module1.ResponseBody
    :<|>
    "Route2" :> Get '[JSON] Module2.ResponseBody

main = let swagger = toOpenApi (Proxy :: Proxy MyApi) in
  B.putStrLn $ encodePretty swagger

{
    "components": {
        "schemas": {
            "ResponseBody": {
                "type": "object",
                "properties": {
                    "rbField2": {
                        "items": {},
                        "maxItems": 0,
                        "type": "array",
                        "example": []
                    }
                },
                "required": [
                    "rbField2"
                ]
            }
        }
    },
    "openapi": "3.0.0",
    "paths": {
        "/Route1": {
            "get": {
                "responses": {
                    "200": {
                        "content": {
                            "application/json;charset=utf-8": {
                                "schema": {
                                    "$ref": "#/components/schemas/ResponseBody"
                                }
                            }
                        },
                        "description": ""
                    }
                }
            }
        },
        "/Route2": {
            "get": {
                "responses": {
                    "200": {
                        "content": {
                            "application/json;charset=utf-8": {
                                "schema": {
                                    "$ref": "#/components/schemas/ResponseBody"
                                }
                            }
                        },
                        "description": ""
                    }
                }
            }
        }
    },
    "info": {
        "version": "",
        "title": ""
    }
}