### Terraform Version ```shell Terraform v1.16.0-rc1 on linux_amd64 ``` ### Terraform Configuration Files Since #38352, `import` blocks can be declared in child modules. In practice they only work there if their arguments are literals. Two cases, both failing at `terraform plan`, both passing when moved to the root module. **Case A - `id` referencing a variable of the module** `main.tf`: ```terraform module "child" { source = "./mod" name = "example" } ``` `mod/main.tf`: ```terraform variable "name" { type = string } resource "terraform_data" "this" { input = var.name } import { to = terraform_data.this id = var.name } ``` **Case B - `for_each` referencing a data source of the module** `main.tf`: ```terraform module "child" { source = "./mod" } ``` `mod/ids.txt`: ``` a,b ``` `mod/main.tf`: ```terraform terraform { required_providers { local = { source = "hashicorp/local" } } } data "local_file" "existing" { filename = "${path.module}/ids.txt" } locals { existing = split(",", data.local_file.existing.content) } resource "terraform_data" "this" { for_each = toset(["a", "b"]) input = each.key } import { for_each = toset(local.existing) to = terraform_data.this[each.key] id = each.key } ``` ### Debug Output ``` ``` ### Expected Behavior Both plans succeed, as they do when the same configuration is written in the root module. ### Actual Behavior Case A: ``` Error: Reference to undeclared input variable on mod/main.tf line 11, in import: 11: id = var.name An input variable with the name "name" has not been declared. This variable can be declared with a variable "name" {} block. Error: Invalid import id argument on mod/main.tf line 11, in import: 11: id = var.name The import block "id" argument depends on resource attributes that cannot be determined until apply, so Terraform cannot plan to import this resource. ``` `var.name` *is* declared in `mod/main.tf`. The second error looks like a knock-on effect of the first: nothing here depends on a resource attribute. Case B: ``` Error: Reference to uninitialized local value on mod/main.tf line 23, in import: 23: for_each = toset(local.existing) The local value local.existing was not processed by the most recent operation, this likely means the previous operation either failed or was incomplete due to targeting. ``` The data source is read, but apparently not before the `import` block is expanded. ### Steps to Reproduce 1. Create the files above 2. `terraform init` 3. `terraform plan` ### Additional Context Two things that may help narrowing it down: - In case A, the `id` argument seems to be evaluated in the **root** module scope. Declaring `name` only in the root module, and giving the child module a differently named variable, makes the plan succeed and import `"resolved-from-root"`. `for_each` and `to` do use the child module scope, hence the asymmetry. - In case B, the failure disappears if the resource's own `for_each` also references the same data source, which suggests the `import` block's references do not create a dependency edge of their own. ### References - #38352 - #33474 ### Generative AI / LLM assisted development? Claude assisted me to narrow down the reproduction cases and to write this report