Terraform Version

Terraform v0.12.24

• provider.aws v2.59.0
• provider.github v2.8.1

Affected Resource(s)

• github_team
• (optionally) github_team_membership

Terraform Configuration Files

resource "github_team" "tftest" {
  name        = "tftest"
  description = "Test team"
  privacy     = "closed"
}

Debug Output

Not relevant: trivial to reproduce. Let me know otherwise, because redacting will take some effort.

Expected Behavior

Team created with no members

Actual Behavior

The user under which terraform is run is silently added as a member to the new team. This membership does not appear in the output or state file.

Steps to Reproduce

Create a new team with or without any github_team_membership entries.
Team will be created with members + terraform_user, if terraform_user is not a member.

Important Factoids

Creating the team through GitHub's Web UI (BUI) automatically adds the user creating the team as a member.

References

Presumably, this is because of:
https://github.com/google/go-github/blob/954e7c82b2994a9f418f300c3f1e147f6a51bd29/github/teams.go#L172:24
and
https://developer.github.com/v3/teams/#create-a-team
The latter states:

When you create a new team, you automatically become a team maintainer without explicitly adding yourself to the optional array of maintainers. For more information, see "About teams" in the GitHub Help documentation.