Fix team add/invite logic around when an invite is required

We were accidentally skipping the invite if the user was a member of *any* organization, rather than the specific organization (as intended)

Fixes https://jira.coreos.com/browse/QUAY-880

data/model/test/test_team.py

@@ -0,0 +1,41 @@
+import pytest
+
+from data.model.team import (add_or_invite_to_team, get_organization_team,
+                             create_team, confirm_team_invite, list_team_users)
+from data.model.organization import create_organization
+from data.model.user import get_user, create_user_noverify
+
+from test.fixtures import *
+
+def is_in_team(team, user):
+  return user.username in {u.username for u in list_team_users(team)}
+
+def test_invite_to_team(initialized_db):
+  first_user = get_user('devtable')
+  second_user = create_user_noverify('newuser', 'foo@example.com')
+
+  def run_invite_flow(orgname):
+    # Create an org owned by `devtable`.
+    org = create_organization(orgname, orgname + '@example.com', first_user)
+
+    # Create another team and add `devtable` to it. Since `devtable` is already
+    # in the org, it should be done directly.
+    other_team = create_team('otherteam', org, 'admin')
+    invite = add_or_invite_to_team(first_user, other_team, user_obj=first_user)
+    assert invite is None
+    assert is_in_team(other_team, first_user)
+
+    # Try to add `newuser` to the team, which should require an invite.
+    invite = add_or_invite_to_team(first_user, other_team, user_obj=second_user)
+    assert invite is not None
+    assert not is_in_team(other_team, second_user)
+
+    # Accept the invite.
+    confirm_team_invite(invite.invite_token, second_user)
+    assert is_in_team(other_team, second_user)
+
+  # Run for a new org.
+  run_invite_flow('firstorg')
+
+  # Create another org and repeat, ensuring the same operations perform the same way.
+  run_invite_flow('secondorg')