Incorrect token resolution with RuleTargetInput/FieldAwareEventInput

[jogold]

• I'm submitting a ...

  • 🪲 bug report
  • 🚀 feature request
  • 📚 construct library gap
  • ☎️ security issue or vulnerability => Please see policy
  • ❓ support request => Please see note at the top of this template.

• What is the current behavior?

The RuleTargetInput static methods (FieldAwareEventInput) incorrectly resolve tokens.

The following

const stack = new Stack();
const rule = new Rule(stack, 'Rule', {
  schedule: Schedule.rate(Duration.minutes(1)),
});
class SomeTarget implements IRuleTarget {
  public constructor(private readonly input: RuleTargetInput) {}
  public bind() {
    return { id: 'T1', arn: 'ARN1', input: this.input };
  }
}

const bucket = new Bucket(stack, 'Bucket');

rule.addTarget(new SomeTarget(RuleTargetInput.fromObject({ bucketArn: bucket.bucketArn })));

results in (note the [object Object]):

{
  "Type": "AWS::Events::Rule",
  "Properties": {
    "ScheduleExpression": "rate(1 minute)",
    "State": "ENABLED",
    "Targets": [
      {
        "Arn": "ARN1",
        "Id": "T1",
        "Input": "{\"bucketArn\":\"[object Object]\"}"
      }
    ]
  }
}

• What is the expected behavior (or behavior of feature suggested)?
  Should resolve token correctly, used to work correctly in 0.34.0 (before refactor(core): refactor API of Tokens #2757)

{
  "Type": "AWS::Events::Rule",
  "Properties": {
    "ScheduleExpression": "rate(1 minute)",
    "State": "ENABLED",
    "Targets": [
      {
        "Arn": "ARN1",
        "Id": "T1",
        "Input": {
          "Fn::Join": [
            "",
            [
              "{\"bucketArn\":\"",
              {
                "Ref": "Bucket83908E77"
              },
              "\"}"
            ]
          ]
        }
      }
    ]
  }
}

• Please tell us about your environment:

  • CDK CLI Version: 0.36.0
  • Module Version: 0.36.0
  • OS: Windows 10
  • Language:TypeScript