Swagger's allOf shows up as undefined - rest

Question

I've take the allOf examples in https://github.com/OAI/OpenAPI-Specification/blob/master/versions/2.0.md#models-with-composition, and applied them to parameters schema and responses schema. My allOf parameters and responses, however, show as undefined. When just using Pet instead of Cat, it works fine. Please let me know how to use Swagger's allOf
swagger: '2.0'
# This is your document metadata
info:
version: "0.0.0"
title: <enter your title>
# Describe your paths here
paths:
/test1:
# This is a HTTP operation
post:
description: bla bla
parameters:
- name: Pet
required: true
in: body
description: The Pet.
schema:
$ref: '#/definitions/Pet'
# Expected responses for this operation:
responses:
# Response code
200:
description: Successful response
schema:
$ref: '#/definitions/Pet'
/test2:
# This is a HTTP operation
post:
description: bla bla
parameters:
- name: Cat
required: true
in: body
description: The cat.
schema:
$ref: '#/definitions/Cat'
# Expected responses for this operation:
responses:
# Response code
200:
description: Successful response
schema:
$ref: '#/definitions/Cat'
definitions:
Pet:
type: object
discriminator: petType
properties:
name:
type: string
petType:
type: string
required:
- name
- petType
Cat:
description: A representation of a cat
allOf:
- $ref: '#/definitions/Pet'
- type: object
properties:
huntingSkill:
type: string
description: The measured skill for hunting
default: lazy
enum:
- clueless
- lazy
- adventurous
- aggressive
required:
- huntingSkill

Answer 1

A type field is missing in Cat Definitions Object and therefore swagger-editor shows undefined.
Add type: object as follow can fix it:
Cat:
type: object
description: A representation of a cat
allOf: