OAS3 generator does not correctly implement the nested additionalProperties of this schema.

OAS3GeneratorNestedAdditionalPropsIssue.json

{
  "openapi": "3.0.0",
  "components": {
    "responses": {
      "200": {
        "description": "OK"
      },
      "diagnostic200": {
        "description": "200 OK",
        "content": {
          "application/json": {
            "schema": {
              "$ref": "#/components/schemas/diagnosticReport"
            }
          }
        }
      }
    },
    "schemas": {
      "diagnosticReport": {
        "type": "object",
        "properties": {
          "nodesStatus": {},
          // HERE the ISSUE
          "servicesStatus": {
            "type": "object",
            "description": "Describes current services status by node",
             // THIS IS OK
            "additionalProperties": {
              "type": "object",
              // HERE the internal object is described as 'object'
              // and not as {available: boolean}
              "additionalProperties": {
                "type": "object",
                "properties": {
                  "available": {
                    "type": "boolean"
                  }
                }
              }
            }
          },
          "systemStatus": {},
          "systemErrors": {}
        },
        "additionalProperties": false,
        "description": "Diagnostic report of the system"
      }
    }
  },
  "paths": {
    "/diagnostic": {
      "get": {
        "operationId": "getStatus",
        "summary": "Get system status, available nodes and services",
        "responses": {
          "200": {
            "$ref": "#/components/responses/diagnostic200"
          }
        }
      }
    }
  }
}