random_shuffle crashes when result_count=0

[leonseng]

Terraform CLI and Provider Versions

$ terraform version
Terraform v1.3.6
on linux_amd64

• provider registry.terraform.io/hashicorp/random v3.5.1

Terraform Configuration

resource "random_shuffle" "this" {
  input        = ["hello", "world"]
  result_count = 0
}

Expected Behavior

random_shuffle.this.result should return an empty list.

Actual Behavior

Provider crashes when running terraform apply

│ Error: Provider produced inconsistent result after apply
│ 
│ When applying changes to random_shuffle.subnet_ids, provider "provider[\"registry.terraform.io/hashicorp/random\"]" produced an unexpected new value: .result_count: was cty.NumberIntVal(0), but now cty.NumberIntVal(2).
│ 
│ This is a bug in the provider, which should be reported in the provider's own issue tracker.

Steps to Reproduce

1. terraform apply

How much impact is this issue causing?

High

Logs

https://gist.github.com/leonseng/14969404cbb5fabc137c9e370ef84220

Additional Information

No response

Code of Conduct

• I agree to follow this project's Code of Conduct

[bendbennett]

Hi @leonseng 👋

Thank you for reporting this issue. I have added a triage label to mark this issue for upcoming discussion.

[bflad]

I was able to reproduce that a result_count set to 0 configuration still causes unexpected behavior (error instead of panic after the terraform-plugin-framework migration):

terraform {
  required_providers {
    random = {
      source  = "hashicorp/random"
      version = "3.6.0"
    }
  }
}

resource "random_shuffle" "test" {
  input        = ["hello", "world"]
  result_count = 0
}

output "test" {
  value = random_shuffle.test.result
}

$ terraform apply

Terraform used the selected providers to generate the following execution plan. Resource actions
are indicated with the following symbols:
  + create

Terraform will perform the following actions:

  # random_shuffle.test will be created
  + resource "random_shuffle" "test" {
      + id           = (known after apply)
      + input        = [
          + "hello",
          + "world",
        ]
      + result       = (known after apply)
      + result_count = 0
    }

Plan: 1 to add, 0 to change, 0 to destroy.

Changes to Outputs:
  + test = (known after apply)

Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.

  Enter a value: yes

random_shuffle.test: Creating...
╷
│ Error: Provider produced inconsistent result after apply
│ 
│ When applying changes to random_shuffle.test, provider
│ "provider[\"registry.terraform.io/hashicorp/random\"]" produced an unexpected new value:
│ .result_count: was cty.NumberIntVal(0), but now cty.NumberIntVal(2).
│ 
│ This is a bug in the provider, which should be reported in the provider's own issue tracker.
╵

I believe the requested/expected behavior originally noted in this bug report, setting result to an empty list when result_count is set to 0, is the most valid behavior. The result attribute documentation could likely also use a quick mention that result_count will influence the number of elements (result_count mentions this, but it feels ideal to provide breadcrumbs if someone seeing only the documentation context of the single attribute, such as a hovering over the attribute in editors). Will poke at a fix for this if it looks extremely straightforward.

[github-actions]

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