don't count test users in speedgrader graded count

Returns a separate JSON element consisting solely
of student with vanilla enrollments (not e.g.
student_view_enrollments) so that any test students
are excluded from grading counts.

fixes CNVS-3471

Test plan:
- Access an assignment whose class has a test
student enrolled.
- Go to SpeedGrader.
- Note the values of the  "x / y Graded" indicator
at the upper right of the page.
- Score the test user's assignment.
- The "x / y Graded" values should not have
changed.

Change-Id: I244f4463023bcf385aa609ed04e5b387ede1def9
Reviewed-on: https://gerrit.instructure.com/33684
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Simon Williams <simon@instructure.com>
QA-Review: Anna Koalenz <akoalenz@instructure.com>
Product-Review: Simon Williams <simon@instructure.com>

app/models/assignment.rb

@@ -1193,6 +1193,8 @@ class Assignment < ActiveRecord::Base
       }
     end
 
+    enrollments = context.enrollments_visible_to(user)
+
     res[:context][:students] = students.map { |u|
       u.as_json(:include_root => false,
                 :methods => avatar_methods,
@@ -1200,7 +1202,7 @@ class Assignment < ActiveRecord::Base
     }
     res[:context][:active_course_sections] = context.sections_visible_to(user).
       map{|s| s.as_json(:include_root => false, :only => [:id, :name]) }
-    res[:context][:enrollments] = context.enrollments_visible_to(user).
+    res[:context][:enrollments] = enrollments.
         map{|s| s.as_json(:include_root => false, :only => [:user_id, :course_section_id]) }
     res[:context][:quiz] = self.quiz.as_json(:include_root => false, :only => [:anonymous_submissions])
 
@@ -1213,6 +1215,8 @@ class Assignment < ActiveRecord::Base
     res[:too_many_quiz_submissions] = too_many = too_many_qs_versions?(submissions)
     qs_versions = quiz_submission_versions(submissions, too_many)
 
+    enrollment_types_by_id = enrollments.inject({}){ |h, e| h[e.user_id] ||= e.type; h }
+
     res[:submissions] = submissions.map do |sub|
       json = sub.as_json(:include_root => false,
         :include => {
@@ -1226,7 +1230,8 @@ class Assignment < ActiveRecord::Base
         },
         :methods => [:scribdable?, :scribd_doc, :submission_history, :late],
         :only => submission_fields
-      )
+      ).merge("from_enrollment_type" => enrollment_types_by_id[sub.user_id])
+
       json['submission_history'] = if json['submission_history'] && (quiz.nil? || too_many)
                                      json['submission_history'].map do |version|
                                        version.as_json(

public/javascripts/speed_grader.js

@@ -1260,13 +1260,16 @@ define([
         })
       );
 
-      var gradedStudents = $.grep(jsonData.studentsWithSubmissions, function(s){
-        return (s.submission && s.submission.workflow_state === 'graded');
+      var gradedStudents = $.grep(jsonData.studentsWithSubmissions, function(s) {
+        return (s.submission &&
+                s.submission.workflow_state === 'graded' &&
+                s.submission.from_enrollment_type === "StudentEnrollment"
+        );
       });
-      var scores = $.map(gradedStudents, function(s){
+
+      var scores = $.map(gradedStudents , function(s){
         return s.submission.score;
       });
-      //scores shoud be an array that has all of the scores of the students that have submisisons
 
       if (scores.length) { //if there are some submissions that have been graded.
         $average_score_wrapper.show();
@@ -1288,9 +1291,10 @@ define([
       else { //there are no submissions that have been graded.
         $average_score_wrapper.hide();
       }
+
       $grded_so_far.html(
         I18n.t('portion_graded', '%{x} / %{y} Graded', {
-          x: scores.length,
+          x: gradedStudents.length,
           y: jsonData.context.students.length
         })
       );