Imported heroku_app should include buildpacks

[mmrobins]

After importing an existing heroku app

terraform import module.myappname.heroku_app.app myappname

The initial plans show that I'm adding buildpacks, even though the existing app has buildpacks

$ terraform plan
...
  # module.myappname.heroku_app.app will be updated in-place
  ~ resource "heroku_app" "app" {
      ..
      + buildpacks            = [
          + "heroku/ruby",
          + "https://github.com/heroku/heroku-buildpack-pgbouncer",
        ]
$ heroku buildpacks -a myappname
=== myappname Buildpack URLs
1. heroku/ruby
2. https://github.com/heroku/heroku-buildpack-pgbouncer

Terraform and Heroku Provider Version

% terraform -v
Terraform v0.12.20
+ provider.heroku v2.1.2

Affected Resource(s)

heroku_app

Terraform Configuration Files

resource "heroku_app" "app" {
  name   = var.app_name
  ...
  buildpacks = [
    "heroku/ruby",
    "https://github.com/heroku/heroku-buildpack-pgbouncer",
  ]
}

Expected Behavior

After the initial terraform import the first terraform plan and apply should show the existing buildpacks.

Actual Behavior

The initial plan shows that I'm adding buildpacks that are already there.

References

This is similar to how config_vars don't show a diff until after the first apply https://github.com/terraform-providers/terraform-provider-heroku/issues/247

[thomsonyeh-czi]

+1 - I'm seeing the same issue on imported heroku_app resources in Terraform 0.12.24.