Draft-State Quizzes - "Save It Now" should work

Closes CNVS-13730

This patch enables the (re)publishing functionality in DS mode. The
issue was that the internals were relying on "workflow_state_changed?"
to be truthy in order to re-publish the quiz, which is not the usual
case in DS where the quiz's WState is always "available" and doesn't
really change between authoring updates.

A side change: Canvas::DraftStateValidations is now covered and
responsible for adding the required validations to classes that mix it
in.

TEST PLAN
---- ----

  - create a quiz with draft-state on
  - add a question
  - save the quiz, publish it
  - open a tab on the quiz show page and keep it
  - in another tab, edit the quiz, modify the question, hit "Update
    Question" and switch back to the show quiz tab
  - refresh the page, verify you get the "Save it Now" button
    - push the button
    - refresh again
    - verify that the button no longer re-appears, and that your changes
      were actually published (you can do this by taking the quiz as a
      student)

Change-Id: Idf3b4302b23d6abc483b80796fee753b0e6fba85
Reviewed-on: https://gerrit.instructure.com/37303
Reviewed-by: Derek DeVries <ddevries@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
QA-Review: Caleb Guanzon <cguanzon@instructure.com>
Product-Review: Ahmad Amireh <ahmad@instructure.com>

app/models/assignment.rb

@@ -75,7 +75,6 @@ class Assignment < ActiveRecord::Base
 
   has_one :external_tool_tag, :class_name => 'ContentTag', :as => :context, :dependent => :destroy
   validates_associated :external_tool_tag, :if => :external_tool?
-  validate :validate_draft_state_change, :if => :workflow_state_changed?
   validate :group_category_changes_ok?
   validate :positive_points_possible?
 

app/models/quizzes/quiz.rb

@@ -73,7 +73,6 @@ class Quizzes::Quiz < ActiveRecord::Base
   validate :validate_quiz_type, :if => :quiz_type_changed?
   validate :validate_ip_filter, :if => :ip_filter_changed?
   validate :validate_hide_results, :if => :hide_results_changed?
-  validate :validate_draft_state_change, :if => :workflow_state_changed?
   validate :validate_correct_answer_visibility, :if => lambda { |quiz|
     quiz.show_correct_answers_at_changed? ||
       quiz.hide_correct_answers_at_changed?
@@ -81,7 +80,7 @@ class Quizzes::Quiz < ActiveRecord::Base
   sanitize_field :description, CanvasSanitize::SANITIZE
   copy_authorized_links(:description) { [self.context, nil] }
 
-  before_save :generate_quiz_data_on_publish
+  before_save :generate_quiz_data_on_publish, :if => :needs_republish?
   before_save :build_assignment
   before_save :set_defaults
   before_save :flag_columns_that_need_republish
@@ -149,25 +148,26 @@ class Quizzes::Quiz < ActiveRecord::Base
   # generate quiz data and update time when we publish. This method makes it
   # harder to mess up (like someone setting using workflow_state directly)
   def generate_quiz_data_on_publish
-    # when draft state is turned on permanently, remove this conditional, the
-    # @publishing ivar from publish!, and change the filter to:
-    #
-    #  before_save :generate_quiz_data_on_publish, :if => :workflow_state_changed?
-    #
-    if context.feature_enabled?(:draft_state)
-      return unless workflow_state_changed?
-
-    # pre-draft state we need ability to republish things. Since workflow_state
-    # is stays available, we need to flag when we're forcing to publish!
-    else
-      return unless @publishing
-    end
-
     if workflow_state == 'available'
       self.generate_quiz_data
       self.published_at = Time.zone.now
     end
   end
+  private :generate_quiz_data_on_publish
+
+  # @return [Boolean] Whether the quiz has unsaved changes due for a republish.
+  def needs_republish?
+    # TODO: remove this conditional and the non-DS scenario once Draft State is
+    # permanently turned on
+    if context.feature_enabled?(:draft_state)
+      return true if @publishing || workflow_state_changed?
+
+    # pre-draft state we need ability to republish things. Since workflow_state
+    # stays available, we need to flag when we're forcing to publish!
+    else
+      return true if @publishing
+    end
+  end
 
   # some attributes require us to republish for non-draft state
   # We can safely remove this when draft state is permanent

lib/canvas/draft_state_validations.rb

@@ -1,5 +1,11 @@
 module Canvas
   module DraftStateValidations
+    def self.included(base)
+      base.class_eval do
+        validate :validate_draft_state_change, :if => :workflow_state_changed?
+      end
+    end
+
     def validate_draft_state_change
       old_draft_state, new_draft_state = self.changes['workflow_state']
       return if old_draft_state == new_draft_state

spec/lib/canvas/draft_state_validations_spec.rb

@@ -0,0 +1,40 @@
+#
+# Copyright (C) 2011 Instructure, Inc.
+#
+# This file is part of Canvas.
+#
+# Canvas is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Affero General Public License as published by the Free
+# Software Foundation, version 3 of the License.
+#
+# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License along
+# with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+
+require File.expand_path(File.dirname(__FILE__) + '/../../spec_helper.rb')
+
+describe Canvas::DraftStateValidations do
+  shared_examples_for "Canvas::DraftStateValidations" do
+    describe ":validate_draft_state_change" do
+      it "should work" do
+        subject.workflow_state = 'unpublished'
+        subject.stubs(has_student_submissions?: true)
+        subject.stubs(workflow_state_changed?: true)
+        subject.stubs({
+          changes: { 'workflow_state' => [ 'published', 'unpublished' ] }
+        })
+        subject.save
+
+        subject.errors[:workflow_state].should be_present
+        subject.errors[:workflow_state][0].to_s.should match(
+          %r{can't unpublish if there are student submissions}i
+        )
+      end
+    end
+  end
+end

spec/models/quizzes/quiz_spec.rb

@@ -17,6 +17,7 @@
 #
 
 require File.expand_path(File.dirname(__FILE__) + '/../../spec_helper.rb')
+require File.expand_path(File.dirname(__FILE__) + '/../../lib/canvas/draft_state_validations_spec.rb')
 
 describe Quizzes::Quiz do
   before :once do
@@ -103,6 +104,8 @@ describe Quizzes::Quiz do
     end
   end
 
+  it_should_behave_like 'Canvas::DraftStateValidations'
+
   it "should flag as edited if shuffle answers changes to off" do
     q = @course.quizzes.create!(:title => "new quiz")
     q.quiz_questions.create!
@@ -1171,6 +1174,37 @@ describe Quizzes::Quiz do
     end
   end
 
+  describe '#needs_republish?' do
+    subject { @course.quizzes.create!(title: 'Test Quiz') }
+
+    it 'should be true if publish! was manually called' do
+      subject.needs_republish?.should be_false
+
+      # intercepting the call to save! and running our expectations there
+      # because by the time it's saved, #needs_republish? will be reset
+      subject.expects(:save!).with { |*args|
+        subject.needs_republish?.should be_true
+        true
+      }
+
+      subject.publish!
+    end
+
+    context 'with draft-state' do
+      before do
+        subject.context.root_account.enable_feature!(:draft_state)
+      end
+
+      it 'should be true if the workflow_state has changed' do
+        subject.workflow_state = 'deleted'
+        subject.save!
+        subject.reload
+        subject.workflow_state = 'available'
+        subject.needs_republish?.should be_true
+      end
+    end
+  end
+
   describe "#current_regrade" do
 
     before(:once) { @quiz = @course.quizzes.create! title: 'Test Quiz' }