X-Git-Url: https://git.openstreetmap.org/rails.git/blobdiff_plain/84c898173778ece298b6bcd6d9839c207a831a86..7406ae5dcc9cbb177a8ea33085af9caf6e3ebb1b:/test/models/user_test.rb

diff --git a/test/models/user_test.rb b/test/models/user_test.rb
index d21512f2a..42949504f 100644
--- a/test/models/user_test.rb
+++ b/test/models/user_test.rb
@@ -94,6 +94,36 @@ class UserTest < ActiveSupport::TestCase
     end
   end
 
+  def test_display_name_user_id_new
+    existing_user = create(:user)
+    user = build(:user)
+
+    user.display_name = "user_#{existing_user.id}"
+    assert_not user.valid?, "user_<id> name is valid for existing user id when it shouldn't be"
+
+    user.display_name = "user_#{existing_user.id + 1}"
+    assert_not user.valid?, "user_<id> name is valid for new user id when it shouldn't be"
+  end
+
+  def test_display_name_user_id_rename
+    existing_user = create(:user)
+    user = create(:user)
+
+    user.display_name = "user_#{existing_user.id}"
+    assert_not user.valid?, "user_<id> name is valid for existing user id when it shouldn't be"
+
+    user.display_name = "user_#{user.id}"
+    assert_predicate user, :valid?, "user_<id> name is invalid for own id, when it should be"
+  end
+
+  def test_display_name_user_id_unchanged_is_valid
+    user = build(:user, :display_name => "user_0")
+    user.save(:validate => false)
+    user.reload
+
+    assert_predicate user, :valid?, "user_0 display_name is invalid but it hasn't been changed"
+  end
+
   def test_friends_with
     alice = create(:user, :active)
     bob = create(:user, :active)