fix "message students who scored more/less than" and 0 scores

refs #3783

Change-Id: Idfd66601f0dd82a0e1f492a84d3526d77973ee4f
Reviewed-on: https://gerrit.instructure.com/2276
Tested-by: Hudson <hudson@instructure.com>
Reviewed-by: Brian Whitmer <brian@instructure.com>

Author: codekitchen

public/javascripts/gradebooks.js

@@ -375,9 +375,9 @@
                   if(selected == "Haven't submitted yet") {
                     return !student.submitted_at && !student.graded_at;
                   } else if(selected == "Scored less than") {
-                    return student.score != null && student.score != "" && cutoff != null && student.score < cutoff;
+                    return student.score != null && student.score !== "" && cutoff != null && student.score < cutoff;
                   } else if(selected == "Scored more than") {
-                    return student.score != null && student.score != "" && cutoff != null && student.score > cutoff;
+                    return student.score != null && student.score !== "" && cutoff != null && student.score > cutoff;
                   }
                 });
                 return $.map(students, function(student) { return student.user_data.id });

public/javascripts/message_students.js

@@ -99,7 +99,10 @@
       var idx = parseInt($(this).val(), 10) || 0;
       var option = currentSettings.options[idx];
       var students_hash = $message_students_dialog.data('students_hash'),
-          cutoff = parseFloat($message_students_dialog.find(".cutoff_score").val(), 10) || null;
+          cutoff = parseFloat($message_students_dialog.find(".cutoff_score").val(), 10);
+      if (!cutoff && cutoff !== 0) {
+        cutoff = null;
+      }
       var student_ids = null;
       var students_list = [];
       for(var idx in students_hash) { students_list.push(students_hash[idx]); }
@@ -125,4 +128,4 @@
       }
     });
   });
-})();
+})();