Using null in AWS::Serverless::StateMachine in the ResultPath throws incorrect E0000 error

StateMachines allow for a null value in the ResultPath Property to pass input directly to the output

Below is a minimal example of a template that is proper but flagged as invalid

AWSTemplateFormatVersion: 2010-09-09
Transform: AWS::Serverless-2016-10-31

Resources:
  rLambda:
    Type: AWS::Serverless::Function
    Properties:
      Handler: index.handler
      Runtime: python3.6
      InlineCode: |
        def handler(event, context):
          print(event)
          return


  rTestMachine:
    Type: AWS::Serverless::StateMachine
    Properties:
      Definition: 
        StartAt: myState
        States:
          myState:
            Type: Task
            Resource:  !GetAtt rLambda.Arn
            ResultPath: null
            End: true
      Policies:
      - Statement:
        - Sid: Test
          Effect: Allow
          Action:
          - lambda:Invoke*
          Resource: !GetAtt rLambda.Arn

Adding quotes around null does not resolve the issue as the value of the property needs to evaluate to null. An exception for null checking should be added for this Parameter

[nikgibbens]

Where are we at with this? It’s 2022 and the problem still persists in CloudFormation with YAML.

[kddejong]

that is useful and I wonder if its a bug in how the AWS::LanguageExtensions works.