fix: dont send noti when editor does not want to

fixes VICE-4499
flag=none

Test plan:
- Create a delayed announcement
- Edit its message and from date so its available
- click save & dont send
- no notification is sent

Change-Id: Ib59b967c913dbf2522a4e896cd623984eab940e7
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/354220
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Reviewed-by: Ádám Molnár <adam.molnar@instructure.com>
Product-Review: Tamás Balogh <tamas.balogh@instructure.com>
QA-Review: Dora Csolakov <dora.csolakov@instructure.com>

app/models/announcement.rb

@@ -81,7 +81,7 @@ class Announcement < DiscussionTopic
     dispatch :new_announcement
     to { users_with_permissions(active_participants_include_tas_and_teachers(true) - [user]) }
     whenever do |record|
-      is_new_announcement = (record.just_created and !(record.post_delayed? || record.unpublished?)) || record.changed_state(:active, :unpublished) || record.changed_state(:active, :post_delayed)
+      is_new_announcement = (record.just_created and !(record.post_delayed? || record.unpublished?)) || record.changed_state(:active, :unpublished)
 
       record.send_notification_for_context? && (is_new_announcement || record.notify_users)
     end
@@ -90,8 +90,9 @@ class Announcement < DiscussionTopic
     dispatch :announcement_created_by_you
     to { user }
     whenever do |record|
-      record.send_notification_for_context? and
-        ((record.just_created and !(record.post_delayed? || record.unpublished?)) || record.changed_state(:active, :unpublished) || record.changed_state(:active, :post_delayed))
+      is_new_announcement = (record.just_created and !(record.post_delayed? || record.unpublished?)) || record.changed_state(:active, :unpublished)
+
+      record.send_notification_for_context? && is_new_announcement
     end
     data { course_broadcast_data }
   end

app/models/discussion_topic.rb

@@ -980,6 +980,7 @@ class DiscussionTopic < ActiveRecord::Base
     state :unpublished
     state :post_delayed do
       event :delayed_post, transitions_to: :active do
+        self.notify_users = true
         self.last_reply_at = Time.now
         self.posted_at = Time.now
       end

spec/models/announcement_spec.rb

@@ -243,5 +243,41 @@ describe Announcement do
       expect(to_users).to include(@student)
       expect(to_users).to_not include(other_student)
     end
+
+    it "does not broadcast if it just got edited to active, if notify_users is false" do
+      course_with_student(active_all: true)
+      notification_name = "New Announcement"
+      Notification.create(name: notification_name, category: "TestImmediately")
+
+      announcement_model(user: @teacher, workflow_state: :post_delayed, notify_users: false, context: @course)
+
+      expect do
+        @a.publish!
+      end.not_to change { @a.messages_sent[notification_name] }
+    end
+
+    it "still broadcasts if it just got edited to active, if notify_users is true" do
+      course_with_student(active_all: true)
+      notification_name = "New Announcement"
+      Notification.create(name: notification_name, category: "TestImmediately")
+
+      announcement_model(user: @teacher, workflow_state: :post_delayed, notify_users: true, context: @course)
+
+      expect do
+        @a.publish!
+      end.to change { @a.messages_sent[notification_name] }
+    end
+
+    it "still broadcasts on delayed_post event even if notify_users was false" do
+      course_with_student(active_all: true)
+      notification_name = "New Announcement"
+      Notification.create(name: notification_name, category: "TestImmediately")
+
+      announcement_model(user: @teacher, workflow_state: :post_delayed, notify_users: false, context: @course)
+
+      expect do
+        @a.delayed_post
+      end.to change { @a.messages_sent[notification_name] }
+    end
   end
 end