make submission uploads support group commenting

closes CNVS-6879

Test plan:
  * make a group assignment
  * submit homework for some groups
  * download the submissions
  * upload the submissions
  * the uploaded attachments should have gone to each student in the
    group

Change-Id: Ia2d95eb13b75803c184441bb07ec853bf75e4938
Reviewed-on: https://gerrit.instructure.com/23661
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Simon Williams <simon@instructure.com>
QA-Review: Amber Taniuchi <amber@instructure.com>
Product-Review: Cameron Matheson <cameron@instructure.com>

app/controllers/gradebooks_controller.rb

@@ -333,8 +333,8 @@ class GradebooksController < ApplicationController
     end
     @comments, @failures = @assignment.generate_comments_from_files(params[:submissions_zip].path, @current_user)
     flash[:notice] = t('notices.uploaded',
-                       { :one => "Files and comments created for 1 user submission",
-                         :other => "Files and comments created for %{count} user submissions" },
+                       { :one => "Files and comments created for 1 submission",
+                         :other => "Files and comments created for %{count} submissions" },
                        :count => @comments.length)
   end
 

app/models/assignment.rb

@@ -1216,12 +1216,20 @@ class Assignment < ActiveRecord::Base
     file_map = zip_extractor.unzip_files.map { |f| infer_comment_context_from_filename(f) }.compact
     files_for_user = file_map.group_by { |f| f[:user] }
     comments = files_for_user.map do |user, files|
-      comment = t :comment_from_files, { :one => "See attached file", :other => "See attached files" }, :count => files.size
-      submission = files.first[:submission]
       attachments = files.map { |g|
         FileInContext.attach(self, g[:filename], g[:display_name])
       }
-      submission.add_comment(:comment => comment, :author => commenter, :attachments => attachments, :hidden => muted?)
+      comment = {
+        comment: t(:comment_from_files, {one: "See attached file", other: "See attached files"}, count: files.size),
+        author: commenter,
+        hidden: muted?,
+        attachments: attachments,
+      }
+      group, students = group_students(user)
+      students.map { |student|
+        submission = find_or_create_submission(student)
+        submission.add_comment(comment)
+      }
     end
     [comments.compact, @ignored_files]
   end

app/models/submission.rb

@@ -808,6 +808,7 @@ class Submission < ActiveRecord::Base
     end
     if self.group
       # this is a bit icky, as it assumes the same opts hash will be passed in to each add_comment call for the group
+      # s|a bit icky|milk-curdling/vomit-inducing/baby-punching|
       opts[:group_comment_id] ||= AutoHandle.generate_securish_uuid
     end
     self.save! if self.new_record?

app/views/gradebooks/submissions_zip_upload.html.erb

@@ -64,7 +64,7 @@
 <% if @comments.empty? %>
   <li><%= t(:no_comments_added, "No Comments Added") %></li>
 <% end %>
-<% @comments.each do |comment| %>
+<% @comments.flatten.each do |comment| %>
   <li>
     <a href="<%= context_url(@context, :context_assignment_submission_url, @assignment.id, comment.submission.user_id) %>"><%= comment.submission.user.name %></a>
     <ul class="file_list">

spec/models/assignment_spec.rb

@@ -2370,9 +2370,29 @@ describe Assignment do
         zip.open.path,
         @teacher)
 
-      comments.map { |c| c.submission.user }.should == [s1]
+      comments.map { |g| g.map { |c| c.submission.user } }.should == [[s1]]
       ignored.should be_empty
     end
+
+    it "should work for groups" do
+      s1, s2 = @students
+
+      gc = @course.group_categories.create! name: "Homework Groups"
+      @assignment.update_attributes group_category_id: gc.id,
+                                    grade_group_students_individually: false
+      g1, g2 = 2.times.map { |i| gc.groups.create! name: "Group #{i}" }
+      g1.add_user(s1)
+      g1.add_user(s2)
+
+      submit_homework(s1)
+      zip = zip_submissions
+
+      comments, _ = @assignment.generate_comments_from_files(
+        zip.open.path,
+        @teacher)
+
+      comments.map { |g| g.map { |c| c.submission.user } }.should == [[s1, s2]]
+    end
   end
 end