### Terraform Version ```shell Terraform v1.15.0 on linux_amd64 ``` ### Terraform Configuration Files You can find the full reproduction in this [GitHub repository](https://github.com/Veetaha/terraform-1-15-variable-validation-regression). Copying the code below just in case. `main.tf` ```terraform module "parent" { source = "./parent" parent_variable = "input" } ``` `parent/main.tf` ```terraform variable "parent_variable" { type = string validation { condition = regexall(".*", var.parent_variable) == tolist([var.parent_variable]) error_message = "My error message" } } module "child" { source = "./child" child_variable = var.parent_variable } ``` `child/main.tf` ```terraform variable "child_variable" { type = string } ``` ### Debug Output [Logs from terraform 1.15.0](https://github.com/Veetaha/terraform-1-15-variable-validation-regression/blob/master/terraform-init-1.15.0.log) [Logs from terraform 1.14.9 (for comparsion)](https://github.com/Veetaha/terraform-1-15-variable-validation-regression/blob/master/terraform-init-1.14.9.log) ### Expected Behavior No regression is expected. The provided configuration should be fully valid in Terraform 1.15.0 like it already is in 1.14.9. ### Actual Behavior The command `terraform init` fails: ```log Initializing modules... - parent in parent - parent.child in parent/child ╷ │ Error: Invalid value for variable │ │ on main.tf line 3, in module "parent": │ 3: parent_variable = "input" │ │ My error message │ │ This was checked by the validation rule at parent/main.tf:3,3-13. ╵ ``` ### Steps to Reproduce Run `terraform init` with the provided configration or use [`./reproduce.sh 1.15.0`](https://github.com/Veetaha/terraform-1-15-variable-validation-regression/blob/master/reproduce.sh) in the reproduction repository. ### Additional Context Changing the `condition` to `regexall(".*", var.parent_variable) != tolist([var.parent_variable])` doesn't change anything. `terraform init` still fails with the same error. So this isn't the question of wether that expression returns `true` or `false`. There is something broken in the processing of the expression's structure itself. ### References _No response_ ### Generative AI / LLM assisted development? No