调整

app/controllers/courses_controller.rb

@@ -298,7 +298,13 @@ class CoursesController < ApplicationController
     @applications = CourseMessage.unhandled_join_course_requests_by_course(@course).
         joins("join users on course_messages.course_message_id=users.id").
         where("LOWER(concat(users.lastname, users.firstname)) LIKE ?", "%#{search_str}%")
-    @teacher_list_size = @course.teachers.size
+    if @course.try(:id) != 1309 || current_user.admin? || current_user.try(:id) == 15582
+      teacher_list = @course.course_members.where("course_members.role in (1, 2, 3)")
+    else
+      teacher_list = @course.course_members.where("(course_members.role in (1, 3) or (course_members.user_id = #{current_user.id}
+                                          and course_members.role = 2))")
+    end
+    @teacher_list_size = teacher_list.size
     @applications_size = CourseMessage.unhandled_join_course_requests_by_course(@course).size
     @is_admin = @user_course_identity < Course::PROFESSOR
   end