Redmine

    involved_principals = []

      involved_principals =

        [@issue.author, @issue.prior_assigned_to].uniq.compact.map do |principal|

          [principal, {:disabled => !collection.include?(principal)}]

        end

    users, groups = collection.sort.partition {|principal| principal.is_a?(User)}

    if involved_principals.blank? && groups.blank?

      s << principals_option_tags(users, selected)

      optgroups = [[l(:label_involved_principals), involved_principals]]

      optgroups.concat(

        case Setting.assignee_dropdown_display_format.to_s

        when 'groups_then_users'

          [

            [l(:label_group_plural), groups],

            [l(:label_user_plural), users]

          ]

        when 'users_by_group'

          principal_users_by_group_optgroups_for_select(users, groups)

        else

          # Default to 'users_then_groups'

          [

            [l(:label_user_plural), users],

            [l(:label_group_plural), groups]

          ]

        end

      )

      optgroups.each do |label, principals|

        options_html = principals_option_tags(principals, selected)

  # Renders option tags for users and groups, preserving per-option attributes.

  def principals_option_tags(principals, selected)

    principals.map do |principal, options|

      options ||= {}

      selected_attribute = %( selected="selected") if option_value_selected?(principal, selected) || principal.id.to_s == selected

      disabled_attribute = %( disabled="disabled") if options[:disabled]

      %(<option value="#{principal.id}"#{selected_attribute}#{disabled_attribute}>#{h principal.name}</option>)

    end.join

  end

  # Builds optgroups that list groups first, then each group's users, then ungrouped users.

  def principal_users_by_group_optgroups_for_select(users, groups)

    users_by_group_optgroups =

      groups.filter_map do |group|

        group_user_ids = group.users.ids

        group_users = users.select {|user| group_user_ids.include?(user.id)}

        [group, group_users] if group_users.present?

      end

    users_by_group_ids = users_by_group_optgroups.flat_map {|_, principals| principals.map(&:id)}.uniq

    ungrouped_users = users.reject {|user| users_by_group_ids.include?(user.id)}

    [[l(:label_group_plural), groups]] +

      users_by_group_optgroups.map {|group, principals| [group.name, principals]} +

      [[l(:label_user_plural), ungrouped_users]]

  end

      [:label_assignee_dropdown_display_format_groups_then_users, 'groups_then_users'],

      [:label_assignee_dropdown_display_format_users_by_group, 'users_by_group']

  label_assignee_dropdown_display_format_users_by_group: Users by group

  def test_new_should_render_users_by_group_in_assignee_select_when_configured

    project = Project.find(1)

    group_a = Group.find(10)

    group_b = Group.find(11)

    project.members << Member.new(:principal => group_a, :roles => [Role.givable.first])

    project.members << Member.new(:principal => group_b, :roles => [Role.givable.first])

    with_settings :issue_group_assignment => '1', :assignee_dropdown_display_format => 'users_by_group' do

      @request.session[:user_id] = 2

      get :new, :params => {:project_id => project.id}

      assert_response :success

    end

    assert_select 'select[name=?]', 'issue[assigned_to_id]' do

      assert_select %(optgroup:nth-of-type(1)[label="#{l(:label_group_plural)}"]) do

        assert_select 'option[value="10"]', text: 'A Team'

        assert_select 'option[value="11"]', text: 'B Team'

      end

      assert_select 'optgroup:nth-of-type(2)[label="A Team"]' do

        assert_select 'option[value="8"]', text: 'User Misc'

      end

      assert_select 'optgroup:nth-of-type(3)[label="B Team"]' do

        assert_select 'option[value="8"]', text: 'User Misc'

      end

      assert_select %(optgroup:nth-of-type(4)[label="#{l(:label_user_plural)}"]) do

        assert_select 'option[value="2"]', text: 'John Smith'

        assert_select 'option[value="8"]', 0

      end

    end

  end

  def test_principals_options_for_select_with_users_and_groups_with_users_by_group

    User.current = nil

    set_language_if_valid 'en'

    principals = [User.find(2), User.find(8), Group.find(11), Group.find(10)]

    with_settings :assignee_dropdown_display_format => 'users_by_group' do

      result = principals_options_for_select(principals)

      assert_select_in result, 'optgroup:nth-of-type(1)[label="Groups"]' do

        assert_select 'option[value="10"]', text: 'A Team'

        assert_select 'option[value="11"]', text: 'B Team'

      end

      assert_select_in result, 'optgroup:nth-of-type(2)[label="A Team"]' do

        assert_select 'option[value="8"]', text: 'User Misc'

      end

      assert_select_in result, 'optgroup:nth-of-type(3)[label="B Team"]' do

        assert_select 'option[value="8"]', text: 'User Misc'

      end

      assert_select_in result, 'optgroup:nth-of-type(4)[label="Users"]' do

        assert_select 'option[value="2"]', text: 'John Smith'

        assert_select 'option[value="8"]', 0

      end

    end

  end