Terraform: 0.12-alpha2: crash when referencing an undeclared module call

[shikloshi]

Terraform Version

Terraform v0.12.0-alpha2
+ provider.aws v1.40.0-6-gb23683732
+ provider.random v2.0.0-5-g612dff2

Terraform Configuration Files

provider random {}

variable length {
  type = number
  default = 10
}

variable prefix {
  type = string
  default = ""
}

resource random_pet new_pet {
  prefix = var.prefix
  length = var.length
}

output pet {
  value = module.new_pet
}

Debug Output

Crash Output

https://gist.github.com/shikloshi/1735d67ae2e9e67f9a04c99ed6401745

Expected Behavior

Terraform should be able to apply or return a syntax error if such had happened.

Actual Behavior

Terraform crashed.

Steps to Reproduce

terraform init

terraform apply

Additional Context

Configuration provided is the only file exists

This started happening when I added the output clause.

References

[apparentlymart]

Hi @shikloshi! Thanks for reporting this issue.

Indeed it looks like we're missing some validation to ensure that module "new_pet" is declared before resolving it. We'll make sure this is fixed before final release.

[hashibot[bot]]

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.

If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.