Terraform[1] - inconsistent list element types

[enchorb]

Terraform Version

Terraform v1.3.3
on linux_amd64 

Debug Output

!!!!!!!!!!!!!!!!!!!!!!!!!!! TERRAFORM CRASH !!!!!!!!!!!!!!!!!!!!!!!!!!!!

Terraform crashed! This is always indicative of a bug within Terraform.
Please report the crash with Terraform[1] so that we can fix this.

When reporting bugs, please include your terraform version, the stack trace
shown below, and any additional information which may help replicate the issue.

[1]: https://github.com/hashicorp/terraform/issues

!!!!!!!!!!!!!!!!!!!!!!!!!!! TERRAFORM CRASH !!!!!!!!!!!!!!!!!!!!!!!!!!!!

inconsistent list element types (cty.Object(map[string]cty.Type{"ack_deadline_seconds":cty.String, "enable_exactly_once_delivery":cty.Bool, "enable_message_ordering":cty.Bool, "expiration_days":cty.Number, "message_retention_duratio
n":cty.Number, "name":cty.String, "push_endpoint":cty.String, "retain_acked_messages":cty.Bool}) then cty.Object(map[string]cty.Type{"ack_deadline_seconds":cty.String, "enable_exactly_once_delivery":cty.Bool, "enable_message_orderin
g":cty.Bool, "expiration_days":cty.String, "message_retention_duration":cty.Number, "name":cty.String, "push_endpoint":cty.String, "retain_acked_messages":cty.Bool}))
module.server.google_cloud_run_domain_mapping.server["doots"]: Refreshing state... [id=locations/us-central1/namespaces/earthone-dev/domainmappings/doots.earthone.dev]
goroutine 3633 [running]:
runtime/debug.Stack()
        /usr/local/go/src/runtime/debug/stack.go:24 +0x65
runtime/debug.PrintStack()
        /usr/local/go/src/runtime/debug/stack.go:16 +0x19
github.com/hashicorp/terraform/internal/logging.PanicHandler()
        /home/circleci/project/project/internal/logging/panic.go:55 +0x153
panic({0x21e01a0, 0xc004962c30})
        /usr/local/go/src/runtime/panic.go:884 +0x212
github.com/zclconf/go-cty/cty.ListVal({0xc004cd1200, 0x2, 0x1?})
        /home/circleci/go/pkg/mod/github.com/zclconf/go-cty@v1.11.1/cty/value_init.go:166 +0x42e
github.com/zclconf/go-cty/cty.transform({0x0?, 0x0, 0x0}, {{{0x2b669d0?, 0xc0049627e0?}}, {0x20ef040?, 0xc004948888?}}, {0x2b4dda0, 0xc0008d43d0})
        /home/circleci/go/pkg/mod/github.com/zclconf/go-cty@v1.11.1/cty/walk.go:175 +0xf4a
github.com/zclconf/go-cty/cty.TransformWithTransformer(...)
        /home/circleci/go/pkg/mod/github.com/zclconf/go-cty@v1.11.1/cty/walk.go:130
github.com/hashicorp/hcl/v2/ext/typeexpr.(*Defaults).Apply(0xc001061ae0?, {{{0x2b669d0?, 0xc0049627e0?}}, {0x20ef040?, 0xc004948888?}})
        /home/circleci/go/pkg/mod/github.com/hashicorp/hcl/v2@v2.14.1/ext/typeexpr/defaults.go:38 +0xa7
github.com/hashicorp/terraform/internal/terraform.prepareFinalInputVariableValue({{0xc0065980e0, 0x1, 0x1}, {{}, {0xc000ccbb60, 0xb}}}, 0xc000fe1a58, 0xc00067e1a0)
        /home/circleci/project/project/internal/terraform/eval_variable.go:98 +0xacd
github.com/hashicorp/terraform/internal/terraform.(*nodeModuleVariable).evalModuleVariable(0xc0008946c0?, {0x2b7ceb8?, 0xc0063be0e0?}, 0x1d?)
        /home/circleci/project/project/internal/terraform/node_module_variable.go:239 +0x545
github.com/hashicorp/terraform/internal/terraform.(*nodeModuleVariable).Execute(0xc0008946c0, {0x2b7ceb8, 0xc0063be0e0}, 0x2)
        /home/circleci/project/project/internal/terraform/node_module_variable.go:155 +0x172
github.com/hashicorp/terraform/internal/terraform.(*ContextGraphWalker).Execute(0xc001ac34a0, {0x2b7ceb8, 0xc0063be0e0}, {0x7f44e759b888, 0xc0008946c0})
        /home/circleci/project/project/internal/terraform/graph_walk_context.go:136 +0xc2
github.com/hashicorp/terraform/internal/terraform.(*Graph).walk.func1({0x23aebe0, 0xc0008946c0})
        /home/circleci/project/project/internal/terraform/graph.go:74 +0x2f0
github.com/hashicorp/terraform/internal/dag.(*Walker).walkVertex(0xc000894780, {0x23aebe0, 0xc0008946c0}, 0xc004cd0ec0)
        /home/circleci/project/project/internal/dag/walk.go:381 +0x2f6
created by github.com/hashicorp/terraform/internal/dag.(*Walker).Update
        /home/circleci/project/project/internal/dag/walk.go:304 +0xf65

Expected Behavior

No crash with any optional attribute

Actual Behavior

Additional context provided in code sample below.

Using a list of object with optional attributes will cause a crash if the optional attribute isn't a string or bool and is missing from any element of the list.

What is currently causing the crash is expiration_days since it is an optional attribute of type number and isn't present on all elements of the list of objects. If I was to turn it into a string (optional(string, "31")) and re-run apply then it wouldn't crash.

A crash also happened when I tried to turn the type to any.

Additional Context

main.tf

  topics = [
    {
      name = "test"
      subscribers = [
        {
          name                 = "pull"
          ack_deadline_seconds = 120
        },
        {
          name                 = "push"
          push_endpoint        = "https://test.com/test"
          ack_deadline_seconds = 30
          expiration_days      = 4
        }
      ]
    }
  ]

module "pubsub" {
  for_each    = { for topic in local.topics : topic.name => topic }
  source      = "./modules/pubsub"
  name        = each.value.name
  subscribers = coalesce(each.value.subscribers, [])
}

pubsub variables.tf

variable "subscribers" {
  type = list(object({
    name                         = string
    ack_deadline_seconds         = optional(number, 10)
    message_retention_duration   = optional(number, 604800)
    expiration_days              = optional(number, 31)
    retain_acked_messages        = optional(bool, false)
    enable_message_ordering      = optional(bool, false)
    enable_exactly_once_delivery = optional(bool, false)
    push_endpoint                = optional(string, null)
  }))
  description = "List of subscribers to pubsub topic"
  default     = []
}

Steps to Reproduce

terraform init
terraform apply

References

#31978
This might be related? #32033

[jbardin]

Duplicate of #31978

[github-actions]

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