FIX: modify notification after remove auto_watch_category (#10568)

When a category is removed from `auto_watch_category` we are removing
CategoryUser. However, there are still TopicUser with notification level
set to `watching` which was inherited from Category.

We should move them back to `regular` unless they were modified by a user.

app/assets/javascripts/admin/models/site-setting.js

@@ -32,7 +32,7 @@ SiteSetting.reopenClass({
     data[key] = value;
 
     if (opts["updateExistingUsers"] === true) {
-      data["updateExistingUsers"] = true;
+      data["update_existing_user"] = true;
     }
 
     return ajax(`/admin/site_settings/${key}`, { type: "PUT", data });

app/controllers/admin/site_settings_controller.rb

@@ -20,7 +20,7 @@ class Admin::SiteSettingsController < Admin::AdminController
       value = Upload.get_from_url(value) || ""
     end
 
-    update_existing_users = params[:updateExistingUsers].present?
+    update_existing_users = params[:update_existing_user].present?
     previous_value = SiteSetting.send(id) || "" if update_existing_users
 
     SiteSetting.set_and_log(id, value, current_user)
@@ -58,7 +58,14 @@ class Admin::SiteSettingsController < Admin::AdminController
           notification_level = NotificationLevels.all[:regular]
         end
 
-        CategoryUser.where(category_id: (previous_category_ids - new_category_ids), notification_level: notification_level).delete_all
+        categories_to_unwatch = previous_category_ids - new_category_ids
+        CategoryUser.where(category_id: categories_to_unwatch, notification_level: notification_level).delete_all
+        TopicUser
+          .joins(:topic)
+          .where(notification_level: TopicUser.notification_levels[:watching],
+                 notifications_reason_id: TopicUser.notification_reasons[:auto_watch_category],
+                 topics: { category_id: categories_to_unwatch })
+          .update_all(notification_level: TopicUser.notification_levels[:regular])
 
         (new_category_ids - previous_category_ids).each do |category_id|
           skip_user_ids = CategoryUser.where(category_id: category_id).pluck(:user_id)

spec/requests/admin/site_settings_controller_spec.rb

@@ -65,7 +65,7 @@ describe Admin::SiteSettingsController do
 
           put "/admin/site_settings/default_email_in_reply_to.json", params: {
             default_email_in_reply_to: false,
-            updateExistingUsers: true
+            update_existing_user: true
           }
 
           user2.reload
@@ -86,14 +86,14 @@ describe Admin::SiteSettingsController do
           expect {
             put "/admin/site_settings/default_email_digest_frequency.json", params: {
               default_email_digest_frequency: 30,
-              updateExistingUsers: true
+              update_existing_user: true
             }
           }.to change { UserOption.where(email_digests: true).count }.by(1)
 
           expect {
             put "/admin/site_settings/default_email_digest_frequency.json", params: {
               default_email_digest_frequency: 0,
-              updateExistingUsers: true
+              update_existing_user: true
             }
           }.to change { UserOption.where(email_digests: false).count }.by(User.count)
         end
@@ -120,11 +120,25 @@ describe Admin::SiteSettingsController do
         it 'should update existing users user preference' do
           put "/admin/site_settings/default_categories_watching.json", params: {
             default_categories_watching: category_ids.last(2).join("|"),
-            updateExistingUsers: true
+            update_existing_user: true
           }
 
+          expect(response.status).to eq(200)
           expect(CategoryUser.where(category_id: category_ids.first, notification_level: watching).count).to eq(0)
           expect(CategoryUser.where(category_id: category_ids.last, notification_level: watching).count).to eq(User.real.where(staged: false).count - 1)
+
+          topic = Fabricate(:topic, category_id: category_ids.last)
+          topic_user1 = Fabricate(:topic_user, topic: topic, notification_level: TopicUser.notification_levels[:watching], notifications_reason_id: TopicUser.notification_reasons[:auto_watch_category])
+          topic_user2 = Fabricate(:topic_user, topic: topic, notification_level: TopicUser.notification_levels[:watching], notifications_reason_id: TopicUser.notification_reasons[:user_changed])
+
+          put "/admin/site_settings/default_categories_watching.json", params: {
+            default_categories_watching: "",
+            update_existing_user: true
+          }
+          expect(response.status).to eq(200)
+          expect(CategoryUser.where(category_id: category_ids, notification_level: watching).count).to eq(0)
+          expect(topic_user1.reload.notification_level).to eq(TopicUser.notification_levels[:regular])
+          expect(topic_user2.reload.notification_level).to eq(TopicUser.notification_levels[:watching])
         end
 
         it 'should not update existing users user preference' do
@@ -134,7 +148,19 @@ describe Admin::SiteSettingsController do
             }
           }.to change { CategoryUser.where(category_id: category_ids.first, notification_level: watching).count }.by(0)
 
+          expect(response.status).to eq(200)
           expect(CategoryUser.where(category_id: category_ids.last, notification_level: watching).count).to eq(0)
+
+          topic = Fabricate(:topic, category_id: category_ids.last)
+          topic_user1 = Fabricate(:topic_user, topic: topic, notification_level: TopicUser.notification_levels[:watching], notifications_reason_id: TopicUser.notification_reasons[:auto_watch_category])
+          topic_user2 = Fabricate(:topic_user, topic: topic, notification_level: TopicUser.notification_levels[:watching], notifications_reason_id: TopicUser.notification_reasons[:user_changed])
+          put "/admin/site_settings/default_categories_watching.json", params: {
+            default_categories_watching: "",
+          }
+          expect(response.status).to eq(200)
+          expect(CategoryUser.where(category_id: category_ids.first, notification_level: watching).count).to eq(0)
+          expect(topic_user1.reload.notification_level).to eq(TopicUser.notification_levels[:watching])
+          expect(topic_user2.reload.notification_level).to eq(TopicUser.notification_levels[:watching])
         end
       end
 
@@ -159,7 +185,7 @@ describe Admin::SiteSettingsController do
         it 'should update existing users user preference' do
           put "/admin/site_settings/default_tags_watching.json", params: {
             default_tags_watching: tags.last(2).pluck(:name).join("|"),
-            updateExistingUsers: true
+            update_existing_user: true
           }
 
           expect(TagUser.where(tag_id: tags.first.id, notification_level: watching).count).to eq(0)