This repo is a minimum reproducible example of invalid JSON strings introduced through the use of templates in terraform. It does so by rendering a templatized JSON with a variable and then trying to decode it to a terraform native object.
If the JSON has an unsanitized value, terraform is unable to decode it.
To test, run terraform init to initialize terraform state and providers, followed by a
terraform plan --var 'VAL=good' to see it work, then a terraform plan --var 'VAL="bad' to
see it fail because of an unsanitized value in the JSON.