Expand operator not recognizing a locals' type

[tul1]

Terraform Version

v0.12.6

Terraform Configuration Files

data "cloudplatform_xxxx" "all" {}

locals {
  available_images = [for image in data.cloudplatform_xxxx.all.images: {
                        id = image.id,
                        name = image.name,
                        creation_date = "${formatdate("YYYY", image.creation_date) * 31556926 +
                                           formatdate("MM", image.creation_date) * 2629743 +
                                           formatdate("DD", image.creation_date) * 604800 +
                                           formatdate("hh", image.creation_date) * 3600 +
                                           formatdate("mm", image.creation_date) * 60 +
                                           formatdate("ss", image.creation_date)}"
                     }]

  newest_image_creation_date = max(local.available_images[*].creation_date...)
  newest_image = [for image in local.available_images: 
                    image if image.creation_date == local.newest_image_creation_date
                 ][0]
}

Debug Output

$ terraform console
> max(local.available_images[*].creation_date...)
63757516898

Actual Behavior

Error: Invalid expanding argument value

  on main.tf line 15, in locals:
  15:   newest_image_creation_date = max(local.available_images[*].creation_date...)

The expanding argument (indicated by ...) must be of a tuple, list, or set
type.

Additional Context

When I run the command with terraform console it works well but when I do terraform apply a type error is raised.

[jbardin]

Thanks for filing the issue @tul1,

I was hoping it was the * evaluation here that was being processed incorrectly, but turns out that it's the first for expression that seems to be causing problems. It's possible we don't have the full type information at the point where we're evaluating the ... expansion.

I created a simpler reproduction here that exhibits the same failure, and succeeds in the console as well:

variable "input" {
  type = list(object({
    a = string
    b = number
  }))

  default = [{
    a = "a"
    b = 1
  }]
}

locals {
  objects = [for o in var.input: {
    id = o.a
    num = o.b
  }]
  max_num = max([for o in local.objects: o.num]...)
}

output "max" {
  value = local.max_num
}

[albertomardomingo]

I think I may be running into the same error here (If it's a different one, I'll be happy to fill a new issue).

Running this code:

locals {
  public_files = [
    for filename in fileset(path.module, "/zones/zonename/public/*.yaml") : 
      yamldecode(file(filename)).entries
  ]
  entries_public_yaml = merge(local.public_files...)
}
output "public_files" {
  value = local.public_files
}

works just fine, but running

variable "zone_folder" {
  default = "zones/zonename"
}
locals {
  public_files = [
    for filename in fileset(path.module, "/${var.zone_folder}/public/*.yaml") : 
      yamldecode(file(filename)).entries
  ]
  entries_public_yaml = merge(local.public_files...)
}
output "public_files" {
  value = local.public_files
}

results in the same error:

Error: Invalid expanding argument value
 
  on zonename.tf line 33, in locals:
  33:   entries_public_yaml = merge(local.public_files...)

The expanding argument (indicated by ...) must be of a tuple, list, or set
type.

As far as I can tell, the local.public_files list is exactly the same in both cases (piping the output to files and running a diff against them returns "files are identical")

To be hones, I'm not completely sure wether I'm just blind as a bat, is the same bug, or a completely unrelated one, but since I'm getting the same error, I'd imagine it would at least be somewhat related.

Sorry if this is unrelated and I have to open a new bug.

[timbrammer]

I'd like to +1 this one. I've got a similar situation. Simpler even:

data "null_data_source" "bits" {
  count = 4
  inputs = {
    "key-${count.index}" = count.index
  }
}

output "results" {
  value = values(merge(data.null_data_source.bits.*.outputs...))
}

This gets me:

The expanding argument (indicated by ...) must be of a tuple, list, or set
type.

[hashibot]

Hello! 🤖

This issue seems to be covering the same problem or request as #22404, so we're going to close it just to consolidate the discussion over there. Thanks!

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.