message: API: Document prepare*SetFor duplicate unit test functions
diff: @@ -28,6 +28,14 @@ const should = chai.should();
  const BASE_URL = '/api/duplicate';
  const testHelper = new TestHelper(BASE_URL);
  +/**
  + * Provides simple shared setup functionality currently used by the duplicate access denial unit tests.
  + * It finds a targetCourse (ICourseModel) that doesn't share any of the teachers with the given input course.
  + * Then it finds the courseAdmin (IUserModel; assumed to be a teacher) of that targetCourse and returns both.
  + *
  + * @param course The course for which the "unauthorized teacher set" is to be generated.
  + * @returns An object with the targetCourse and unauthorizedTeacher.
  + */
  async function prepareUnauthorizedTeacherSetFor(course: ICourse) {
  const authorizedTeachers = [course.courseAdmin, ...course.teachers];
  const targetCourse = await Course.findOne({
  @@ -38,13 +46,21 @@ async function prepareUnauthorizedTeacherSetFor(course: ICourse) {
  return {targetCourse, unauthorizedTeacher};
  }
  +/**
  + * Provides simple shared setup functionality currently used by the duplicate access denial unit tests.
  + * It first gets a random teacher for the input course.
  + * Then it finds a targetCourse (ICourseModel) for that teacher.
  + *
  + * @param course The course for which the "other course set" is to be generated.
  + * @returns An object with the targetCourse and teacher.
  + */
  async function prepareOtherTargetCourseSetFor(course: ICourse) {
  const teacher = await FixtureUtils.getRandomTeacherForCourse(course);
  const targetCourse = await Course.findOne({
  courseAdmin: {$ne: teacher},
  teachers: {$ne: teacher}
  });
  - return {teacher, targetCourse};
  + return {targetCourse, teacher};
  }
  async function testForbidden(user: IUser, urlPostfix = '', sendData: object) {
  