openproject/app/models/work_packages/scopes/include_derived_dates.rb

#-- encoding: UTF-8

#-- copyright
# OpenProject is an open source project management software.
# Copyright (C) 2012-2020 the OpenProject GmbH
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License version 3.
#
# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
# Copyright (C) 2006-2017 Jean-Philippe Lang
# Copyright (C) 2010-2013 the ChiliProject Team
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
# See docs/COPYRIGHT.rdoc for more details.
#++

class WorkPackages::Scopes::IncludeDerivedDates
  attr_accessor :user,
                :work_package

  class << self
    def fetch
      WorkPackage
        .left_joins(:descendants)
        .select(*select_statement)
        .group(:id)
    end

    private

    def select_statement
      ["LEAST(MIN(#{descendants_alias}.start_date), MIN(#{descendants_alias}.due_date)) AS derived_start_date",
       "GREATEST(MAX(#{descendants_alias}.start_date), MAX(#{descendants_alias}.due_date)) AS derived_due_date"]
    end

    def descendants_alias
      'descendants_work_packages'
    end
  end
end