Conversion from Typescript template literals and concatenated strings to other languages is broken

[mutahhir]

Python

Converted

1. Reference a property via fqn better

           availability_zone=f"\\${{dataAwsAvailabilityZonesChangemeAzListEbsSnapshot.names.fqn}[0]}",

2. Should not be using terraform escape here?

       aws_iam_role_changeme_spot_and_fargate_iam_role_node_group = aws.iam_role.IamRole(self, "changeme_spot_and_fargate_iam_role_node_group",
   # ...
           name=f"\\${{changemeSpotAndFargateName.value}}-eks-node-group-role"
       )

3. Just generally using the hcl literal escapes wrong

           availability_zone=f"\\${element({changemeSpotAndFargateAvailabilityZones.value}, count.index)}",

4. More complex example

   source_code_hash=f"${{filebase64sha256(\}"\\${{changemeLambdaFunctionZip.value}}\")}"

Error

    Traceback (most recent call last):
      File "/Users/mutahhir/src/scratchpad/terraform-convert-examples/converted-langs/python/aws/main.py", line 11, in <module>
        from aws_ebs_volume.ebs_snapshot.main import MyStack as aws_ebs_volume_ebs_snapshot
      File "/Users/mutahhir/src/scratchpad/terraform-convert-examples/converted-langs/python/aws/aws_ebs_volume/ebs_snapshot/main.py", line 26
        availability_zone=f"\\${{dataAwsAvailabilityZonesChangemeAzListEbsSnapshot.names.fqn}[0]}",
                                                                                                  ^
    SyntaxError: f-string: single '}' is not allowed

Correct way

            availability_zone=f"${{{dataAwsAvailabilityZonesChangemeAzListEbsSnapshot.fqn}.names[0]}}",

---

CSharp

            awsRouteTableChangemeSpotAndFargateRouteTablePrivate.AddOverride("count", $"\\${length({changemeSpotAndFargatePrivateSubnets.value})}");

When it should be:

            awsRouteTableChangemeSpotAndFargateRouteTablePrivate.AddOverride("count", $"\\${{length({changemeSpotAndFargatePrivateSubnets.value})}}");

It shouldn't even need to escape the dollar sign, so even $"${{length... should work too?

[mutahhir]

JSII Issue: https://github.com/aws/jsii/issues/3967

[mutahhir]

Going to mark this as a non-blocker since the release of #2744 as that PR moves away from using string templates and on to string concatenation instead.

[ansgarm]

Wellllll, there's a now string concatenation problem in Python 😂

      File "/Users/ansgar/projects/playground/test-cdktf-convert/main.py", line 30, in __init__
        "description": "changeme-aws-security-group-dynamic-ingress-${" + aws_security_group_changeme_aws_security_group_dynamic_dynamic_iterator0.key + "}",
    TypeError: can only concatenate str (not "_LazyBaseProxy") to str

(more context in the original comment: https://github.com/hashicorp/terraform-cdk/issues/2637#issuecomment-1505210351)

edit: the code above works in TypeScript because the Lazy class has an toString method. This would work in other languages too, if JSII would implement this feature request: https://github.com/aws/jsii/issues/380

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