cf-conditions-property-level-noValue.yml

AWSTemplateFormatVersion: 2010-09-09

Parameters:
  Environment:
    Description: Deploy Environment.
    Type: String
    AllowedValues:
      - prod
      - test

Conditions: 
    IsTestEnvironment: !Equals 
        - !Ref Environment
        - test

Resources:
  Queue:
    Type: 'AWS::SQS::Queue'
      Properties:
        ReceiveMessageWaitTimeSeconds: !If
          - IsTestEnvironment
          - 20
          - Ref: AWS::NoValue