Index: app/controllers/reports_controller.rb
===================================================================
--- app/controllers/reports_controller.rb	(revision 16156)
+++ app/controllers/reports_controller.rb	(working copy)
@@ -24,7 +24,7 @@
     @versions = @project.shared_versions.sort
     @priorities = IssuePriority.all.reverse
     @categories = @project.issue_categories
-    @assignees = (Setting.issue_group_assignment? ? @project.principals : @project.users).sort
+    @assignees = @project.assignable_users.sort
     @authors = @project.users.sort
     @subprojects = @project.descendants.visible
 
@@ -63,7 +63,7 @@
       @report_title = l(:field_category)
     when "assigned_to"
       @field = "assigned_to_id"
-      @rows = (Setting.issue_group_assignment? ? @project.principals : @project.users).sort
+      @rows = @project.assignable_users.sort
       @data = Issue.by_assigned_to(@project)
       @report_title = l(:field_assigned_to)
     when "author"
Index: test/functional/reports_controller_test.rb
===================================================================
--- test/functional/reports_controller_test.rb	(revision 16156)
+++ test/functional/reports_controller_test.rb	(working copy)
@@ -61,4 +61,17 @@
     get :issue_report_details, :id => 1, :detail => 'invalid'
     assert_response 404
   end
+
+  def test_issue_report_show_only_assignable_users_as_assignee
+    project = Project.find(1)
+    get :issue_report, :id => project.id
+    assert_select '.splitcontentleft h3:nth-of-type(3)+table.list tbody tr', project.assignable_users.count
+
+    Role.all.each {|r| r.update_attribute(:assignable, false)}
+    get :issue_report, :id => project.id
+    assert_select '.splitcontentleft h3:nth-of-type(3)+p i', I18n.t(:label_no_data)
+
+    get :issue_report_details, :id => 1, :detail => 'assigned_to'
+    assert_select '#content h3+p i', I18n.t(:label_no_data)
+  end
 end