False negative if YAML has syntax error

We had a developer author a relatively large swagger document that he created and exported from Swagger Editor as swagger.yaml

It would not load in swagger-ui (2.2.3) which we have deployed locally in web server

http://swagger.na.sas.com/swagger-ui/?url=http://swagger.na.sas.com/apis/swagger.bugs/validator/swagger.yaml

I got only

failed to parse JSON/YAML response

and no further indication of what was wrong. I converted the YAML to JSON and that rendered OK in the UI.

I ran it through the validator

http://swagger.na.sas.com/swagger-validator/?url=http://swagger.na.sas.com/apis/swagger.bugs/validator/swagger.yaml

and it passes, showing the badge, and in debug mode

http://swagger.na.sas.com/swagger-validator/debug?url=http://swagger.na.sas.com/apis/swagger.bugs/validator/swagger.yaml

returns

{}

I was only able to find the problem when I turned on JavaScript debugging in Chrome and set it to halt on exceptions and it flagged a YAML error related to a duplicate key in swagger-ui. I was able to find that a schema definition in the larger swagger.yaml file had two description fields. Removing the duplicate field resolved the error.

I'd like to see validator-badge detect and report on this (YAML errors); this will help identify problems. (Also having swagger-ui report the parsing problem would also help, I'll submit another report for that project)

Here is a small sample Swagger 2.0 document that is clean in the editor and validator but does not load in swagger-ui :

swagger: '2.0'
info:
  description: validator-badge does not detect yaml error that causes swagger-ui failure
  version: 1.0.0
  title: validator false negative
host: 'www.example.com'
basePath: /
paths:
  /score:
    get:
      produces:
        - application/json
      responses:
        200:
          description: A score result
          schema:
            $ref: '#/definitions/scoreResult'
definitions:
  scoreResult:
    properties:
      outputs:
        type: string
        description: the score output data
      scoreRequest:
        description: This is the description of this member.
        type: string
        description: Oops, this schema has two description members.
      version:
        type: integer
        format: int32

Reproduce the failure with the sample Swagger 2.0 YAML and compare the validator result with the validator debug response shown in the issue. Trace how validator-badge handles YAML parsing and duplicate keys; done means the validator reports the YAML error instead of returning a successful badge or empty debug response.