### Terraform Version ``` 0.12.9 0.12.10-dev ``` ### Terraform Configuration Files A variable number of resource: ```hcl locals { resource_count = { type1 = { subtypeA = 2 } } resource_data = { type1 = { subtypeA = null_resource.type1A } } } resource "null_resource" "type1A" { count = local.resource_count.type1.subtypeA # ... } ``` which are passed into a module: ```hcl module "mod" { # ... resources = local.resource_data.type1.subtypeA # (Just to explain why I have thart structure, it'd actually look like: # resources = concat( # [ for r in local.resource_data.type1.subtypeA : { ... } ], # [ for r in local.resource_data. ... : { ... } ], # ... # ) # but it's not required for the reproduction.) } ``` which creates resources for each one: ```hcl locals { servers_idx = toset(range(length(var.servers))) servers = { for idx in local.servers_idx : idx => var.servers[idx] } } resource "null_resource" "whatever" { for_each = local.servers # ... } ``` ### Expected Behavior Dropping the resource count from `2` to `1` should impact all resources using it as a `count`/`for_each` in the module. ### Actual Behavior `null_resource.type1A` is correctly destroyed, but index `1` resources using the `local.resource_data` are _replaced_ (in the plan anyway - applying will as a result fail with a cycle). ### Steps to Reproduce 1. `terraform apply` 1. Alter `local.resource_count.type1.subtypeA` from `2` to `1` 1. `terraform plan` ### Additional Context The issue seems to be that the number of items for all resources is evaluated simultaneously and without considering dependencies between them - so since we already have `null_resource.type1A` in the state, it's `length( . )` is used to compute counts for other resource despite that it will change in the current plan. Thus: #### Workaround: Key `local.resource_data` directly on the static counts rather than implicit dependency through `null_resource.type*`: ```hcl locals { resource_data = { type1 = { subtypeA = { for idx in range(local.resource_count.type1.subtypeA) : idx => null_resource.type1A[idx] } } } } ``` ### References