FIX: Don't change automatic group name if localized name has been taken.

app/models/group.rb

@@ -161,7 +161,13 @@ class Group < ActiveRecord::Base
     # don't allow shoddy localization to break this
     localized_name = I18n.t("groups.default_names.#{name}")
     validator = UsernameValidator.new(localized_name)
-    group.name = validator.valid_format? ? localized_name : name
+
+    group.name =
+      if !Group.where(name: localized_name).exists? && validator.valid_format?
+        localized_name
+      else
+        name
+      end
 
     # the everyone group is special, it can include non-users so there is no
     # way to have the membership in a table

spec/models/group_spec.rb

@@ -154,9 +154,42 @@ describe Group do
 
   end
 
-  it "makes sure the everyone group is not visible" do
-    g = Group.refresh_automatic_group!(:everyone)
-    expect(g.visible).to eq(false)
+  describe '.refresh_automatic_group!' do
+    it "makes sure the everyone group is not visible" do
+      g = Group.refresh_automatic_group!(:everyone)
+      expect(g.visible).to eq(false)
+    end
+
+    it "uses the localized name if name has not been taken" do
+      begin
+        default_locale = SiteSetting.default_locale
+        I18n.locale = SiteSetting.default_locale = 'de'
+
+        group = Group.refresh_automatic_group!(:staff)
+
+        expect(group.name).to_not eq('staff')
+        expect(group.name).to eq(I18n.t('groups.default_names.staff'))
+      ensure
+        I18n.locale = SiteSetting.default_locale = default_locale
+      end
+    end
+
+    it "does not use the localized name if name has already been taken" do
+      begin
+        default_locale = SiteSetting.default_locale
+        I18n.locale = SiteSetting.default_locale = 'de'
+
+        another_group = Fabricate(:group,
+          name: I18n.t('groups.default_names.staff')
+        )
+
+        group = Group.refresh_automatic_group!(:staff)
+
+        expect(group.name).to eq('staff')
+      ensure
+        I18n.locale = SiteSetting.default_locale = default_locale
+      end
+    end
   end
 
   it "Correctly handles removal of primary group" do