Panic on apply after destroy

[sethvargo]

Hi there,

Terraform Version

Terraform v0.9.0-dev (9ae0e077f1a43956077f8e0ac7f706f1fb5f3edc)

Affected Resource(s)

• core

Panic Output

https://gist.github.com/sethvargo/9ca97d49f4e754607906bf63db54446b

Expected Behavior

Terraform should not have crashed.

Actual Behavior

Terraform crashed.

Steps to Reproduce

1. Create resources
2. Destroy resources
3. Run apply

Steps to Fix

1. Delete local statefile

Important Factoids

• Using Azure, got an error on destroy, but subsequent destroy succeeded.

[sethvargo]

I've narrowed down the issue. In my configs, I'm grabbing the value of a nested attribute (which is a list of maps):

frontend_ip_configuration_name = "${lookup(azurerm_lb.demo.frontend_ip_configuration[0], "name")}"

Where that is defined as

resource "azurerm_lb" "demo" {
  name                = "demo"
  location            = "${var.azurerm_location}"
  resource_group_name = "${azurerm_resource_group.demo.name}"

  frontend_ip_configuration {
    name                          = "default"
    public_ip_address_id          = "${azurerm_public_ip.demo.id}"
    private_ip_address_allocation = "dynamic"
  }
}

It looks like the graph isn't correctly setting up that dependency.

[mitchellh]

On first look, it appears the graph is being setup properly. This looks like something else. I'm not 100% sure yet but your lookup is weird. I'm not saying you're doing something wrong, but its a usage style that I haven't seen often and I'm not sure how that plays well with computed maps.

Do you have a consistent reproduction?

I can play with this tomorrow.

[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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