Incorrect evaluation of object type when using optional parameter with default value #1543

luckeySK · 2022-10-11T07:54:56Z

luckeySK
Oct 11, 2022

Starting in Terraform 1.3.0 introduced new standard feature - Optional attributes for object type constraints. However TFlint throws error if try to use it with two parameters.

Code from Terraform documentation

variable "with_optional_attribute" {
  type = object({
    a = string                # a required attribute
    b = optional(string)      # an optional attribute
    c = optional(number, 127) # an optional attribute with a default value
  })
}

Actual behavior

TFlint doesn't accept the code above and throws an error:

Error: Invalid type specification

  on variables.tf line 40, in variable "with_optional_attribute":
  40:     c = optional(number, 127) # an optional attribute with a default value

Optional attribute modifier expects only one argument: the attribute type.

Additional Context

$ tflint --version
TFLint version 0.40.0
+ ruleset.terraform (0.1.0-bundled)
$ terraform --version
Terraform v1.3.1
on windows_amd64
+ provider registry.terraform.io/hashicorp/aws v4.34.0