count using a data resource

[Lasering]

I'm so sorry. This is working correctly. I didn't do all the correct tests before creating the issue. Please disregard it.

Terraform Version

Terraform v0.12.1

Terraform Configuration Files

variable "server" {
  type = string
  default = "google.com"
}

data "dns_aaaa_record_set" "server-ipv6" {
  host = var.server
}

resource "null_resource" "test" {
  count = length(data.dns_aaaa_record_set.server-ipv6.addrs)
  <some useful provisioner>
}

Expected Behavior

terraform plan should run successfully.

Actual Behavior

Error: Invalid count argument

  on main.tf line 11, in resource "null_resource" "test":
  11:   count = length(data.dns_aaaa_record_set.server-ipv6.addrs)

The "count" value depends on resource attributes that cannot be determined
until apply, so Terraform cannot predict how many instances will be created.
To work around this, use the -target argument to first apply only the
resources that the count depends on.

Steps to Reproduce

terraform init
terraform plan

Additional Context

It used to work under Terraform v0.12.0.

This comment also conveys the idea it should work.

Even using locals fails:

locals {
  server = "google.com"
}

data "dns_aaaa_record_set" "server-ipv6" {
  host = local.server
}

resource "null_resource" "test" {
  count = length(data.dns_aaaa_record_set.server-ipv6.addrs)
  <some useful provisioner>
}

Is this a regression or is it the intended behavior?

[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.

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