use course nicknames in notifications

test plan:
 - set up multiple users in a course
 - give some of these users different nicknames for the course
 - set up and confirm communication channels for these users
 - do things that cause notification messages to be dispatched
   to the users
 - ensure each user sees the correct course name in his/her
   notification messages

closes CNVS-24168

Change-Id: Ic49c888ae86b40ba42004e3c2dbc205e49480b79
Reviewed-on: https://gerrit.instructure.com/65544
Reviewed-by: Clay Diffrient <cdiffrient@instructure.com>
Tested-by: Jenkins
QA-Review: Ryan Allen <rallen@instructure.com>
Product-Review: Cosme Salazar <cosme@instructure.com>

app/models/course.rb

@@ -2825,4 +2825,13 @@ class Course < ActiveRecord::Base
   def refresh_content_participation_counts(_progress)
     content_participation_counts.each(&:refresh_unread_count)
   end
+
+  def name
+    return @nickname if @nickname
+    read_attribute(:name)
+  end
+
+  def apply_nickname_for!(user)
+    @nickname = nickname_for(user, nil)
+  end
 end

app/models/message.rb

@@ -483,6 +483,9 @@ class Message < ActiveRecord::Base
     user_time_zone     = self.user.try(:time_zone) || original_time_zone
     Time.zone          = user_time_zone
 
+    # (temporarily) override course name with user's nickname for the course
+    hacked_course = apply_course_nickname_to_asset(self.context, self.user)
+
     # Ensure we have a path_type
     path_type = 'dashboard' if to == 'summary'
     unless path_type
@@ -518,6 +521,8 @@ class Message < ActiveRecord::Base
     # Set the timezone back to what it originally was
     Time.zone = original_time_zone if original_time_zone.present?
 
+    hacked_course.apply_nickname_for!(nil) if hacked_course
+
     @i18n_scope = nil
   end
 
@@ -818,4 +823,16 @@ class Message < ActiveRecord::Base
     @_message_context ||= Messages::AssetContext.new(context, notification_name)
   end
 
+  def apply_course_nickname_to_asset(asset, user)
+    hacked_course = if asset.is_a?(Course)
+      asset
+    elsif asset.respond_to?(:context) && asset.context.is_a?(Course)
+      asset.context
+    elsif asset.respond_to?(:course) && asset.course.is_a?(Course)
+      asset.course
+    end
+    hacked_course.apply_nickname_for!(user) if hacked_course
+    hacked_course
+  end
+
 end

spec/models/course_spec.rb

@@ -4305,3 +4305,25 @@ describe Course, '#update_enrolled_users' do
     expect(@user.associated_accounts).to be_blank
   end
 end
+
+describe Course, "#apply_nickname_for!" do
+  before(:once) do
+    @course = Course.create! :name => 'some terrible name'
+    @user = User.new
+    @user.course_nicknames[@course.id] = 'nickname'
+    @user.save!
+  end
+
+  it "sets name to user's nickname (non-persistently)" do
+    @course.apply_nickname_for!(@user)
+    expect(@course.name).to eq 'nickname'
+    @course.save!
+    expect(Course.find(@course).name).to eq 'some terrible name'
+  end
+
+  it "undoes the change with nil user" do
+    @course.apply_nickname_for!(@user)
+    @course.apply_nickname_for!(nil)
+    expect(@course.name).to eq 'some terrible name'
+  end
+end

spec/models/message_spec.rb

@@ -99,6 +99,37 @@ describe Message do
       msg = generate_message(:account_user_notification, :email, @au)
       expect(msg.html_body).to include('awesomelogo.jpg')
     end
+
+    describe "course nicknames" do
+      before(:once) do
+        course_with_student(:active_all => true, :course_name => 'badly-named-course')
+        @student.course_nicknames[@course.id] = 'student-course-nick'
+        @student.save!
+      end
+
+      def check_message(message, asset)
+        msg = generate_message(message, :email, asset, :user => @student)
+        expect(msg.html_body).not_to include 'badly-named-course'
+        expect(msg.html_body).to include 'student-course-nick'
+        expect(@course.name).to eq 'badly-named-course'
+        
+        msg = generate_message(message, :email, asset, :user => @teacher)
+        expect(msg.html_body).to include 'badly-named-course'
+        expect(msg.html_body).not_to include 'student-course-nick'
+      end
+
+      it "applies nickname to asset" do
+        check_message(:grade_weight_changed, @course)
+      end
+
+      it "applies nickname to asset.course" do
+        check_message(:enrollment_registration, @student.enrollments.first)
+      end
+
+      it "applies nickname to asset.context" do
+        check_message(:assignment_changed, @course.assignments.create!)
+      end
+    end
   end
 
   context "named scopes" do