Do not copy subtasks twice when copying an issue and its descendants (#6965).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@10329 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/controllers/issues_controller.rb

@@ -235,6 +235,13 @@ class IssuesController < ApplicationController
 
     unsaved_issue_ids = []
     moved_issues = []
+
+    if @copy && params[:copy_subtasks].present?
+      # Descendant issues will be copied with the parent task
+      # Don't copy them twice
+      @issues.reject! {|issue| @issues.detect {|other| issue.is_descendant_of?(other)}}
+    end
+
     @issues.each do |issue|
       issue.reload
       if @copy