groupUsersSearch doesn't return users with inherited membership

Summary

Originally reported via this (internal only) ticket by a GitLab Premium customer.

Issue boards use the groupUsersSearch graphql query to find users when editing a board:

The below query is used:

query groupUsersSearch($search: String!, $fullPath: ID!, $after: String, $first: Int) {
  workspace: group(fullPath: $fullPath) {
    id
    users: groupMembers(
      search: $search
      relations: [DIRECT, DESCENDANTS, INHERITED]
      first: $first
      after: $after
      sort: USER_FULL_NAME_ASC
    ) {
      pageInfo {
        hasNextPage
        endCursor
        startCursor
        __typename
      }
      nodes {
        id
        user {
          ...User
          ...UserAvailability
          __typename
        }
        __typename
      }
      __typename
    }
    __typename
  }
}

fragment User on User {
  id
  avatarUrl
  name
  username
  webUrl
  __typename
}

fragment UserAvailability on User {
  status {
    availability
    __typename
  }
  __typename
}

The above query only returns direct members of the group. The expectation is that if a group is invited, then all members of the now invited group would also be displayed.

Steps to reproduce

• Create GroupA and GroupB, add members to GroupB
• Create a issue board in GroupA
• Invite GroupB to GroupA
• Edit issue board in GroupA, members of GroupB are not displayed.

Example Project

What is the current bug behavior?

Members of the group via a group invite are not displayed.

What is the expected correct behavior?

All group members should be displayed / returned.

Relevant logs and/or screenshots

See above

Output of checks

This bug happens on GitLab.com