discourse/spec/components/post_destroyer_spec.rb

require 'rails_helper'
require 'post_destroyer'

describe PostDestroyer do

  before do
    UserActionCreator.enable
  end

  let(:moderator) { Fabricate(:moderator) }
  let(:admin) { Fabricate(:admin) }
  let(:post) { create_post }

  describe "destroy_old_hidden_posts" do

    it "destroys posts that have been hidden for 30 days" do
      Fabricate(:admin)

      now = Time.now

      freeze_time(now - 60.days)
      topic = post.topic
      reply1 = create_post(topic: topic)

      freeze_time(now - 40.days)
      reply2 = create_post(topic: topic)
      PostAction.hide_post!(reply2, PostActionType.types[:off_topic])

      freeze_time(now - 20.days)
      reply3 = create_post(topic: topic)
      PostAction.hide_post!(reply3, PostActionType.types[:off_topic])

      freeze_time(now - 10.days)
      reply4 = create_post(topic: topic)

      freeze_time(now)
      PostDestroyer.destroy_old_hidden_posts

      reply1.reload
      reply2.reload
      reply3.reload
      reply4.reload

      expect(reply1.deleted_at).to eq(nil)
      expect(reply2.deleted_at).not_to eq(nil)
      expect(reply3.deleted_at).to eq(nil)
      expect(reply4.deleted_at).to eq(nil)
    end

  end

  describe 'destroy_old_stubs' do
    it 'destroys stubs for deleted by user posts' do
      SiteSetting.delete_removed_posts_after = 24
      Fabricate(:admin)
      topic = post.topic
      reply1 = create_post(topic: topic)
      reply2 = create_post(topic: topic)
      reply3 = create_post(topic: topic)

      PostDestroyer.new(reply1.user, reply1).destroy
      PostDestroyer.new(reply2.user, reply2).destroy

      reply2.update_column(:updated_at, 2.days.ago)

      PostDestroyer.destroy_stubs

      reply1.reload
      reply2.reload
      reply3.reload

      expect(reply1.deleted_at).to eq(nil)
      expect(reply2.deleted_at).not_to eq(nil)
      expect(reply3.deleted_at).to eq(nil)

      # if topic is deleted we should still be able to destroy stubs

      topic.trash!
      reply1.update_column(:updated_at, 2.days.ago)
      PostDestroyer.destroy_stubs

      reply1.reload
      expect(reply1.deleted_at).to eq(nil)

      # flag the post, it should not nuke the stub anymore
      topic.recover!
      PostAction.act(Fabricate(:coding_horror), reply1, PostActionType.types[:spam])

      PostDestroyer.destroy_stubs

      reply1.reload
      expect(reply1.deleted_at).to eq(nil)

      # defer the flag, we should be able to delete the stub
      PostAction.defer_flags!(reply1, Discourse.system_user)
      PostDestroyer.destroy_stubs

      reply1.reload
      expect(reply1.deleted_at).to_not eq(nil)
    end

    it 'uses the delete_removed_posts_after site setting' do
      Fabricate(:admin)
      topic = post.topic
      reply1 = create_post(topic: topic)
      reply2 = create_post(topic: topic)

      PostDestroyer.new(reply1.user, reply1).destroy
      PostDestroyer.new(reply2.user, reply2).destroy

      SiteSetting.delete_removed_posts_after = 1

      reply2.update_column(:updated_at, 70.minutes.ago)

      PostDestroyer.destroy_stubs

      reply1.reload
      reply2.reload

      expect(reply1.deleted_at).to eq(nil)
      expect(reply2.deleted_at).not_to eq(nil)

      SiteSetting.delete_removed_posts_after = 72

      reply1.update_column(:updated_at, 2.days.ago)

      PostDestroyer.destroy_stubs

      expect(reply1.reload.deleted_at).to eq(nil)

      SiteSetting.delete_removed_posts_after = 47

      PostDestroyer.destroy_stubs

      expect(reply1.reload.deleted_at).not_to eq(nil)
    end

    it "deletes posts immediately if delete_removed_posts_after is 0" do
      Fabricate(:admin)
      topic = post.topic
      reply1 = create_post(topic: topic)

      SiteSetting.delete_removed_posts_after = 0

      PostDestroyer.new(reply1.user, reply1).destroy

      expect(reply1.reload.deleted_at).not_to eq(nil)
    end
  end

  describe "recovery and user actions" do
    it "recreates user actions" do
      reply = create_post(topic: post.topic)
      author = reply.user

      post_action = author.user_actions.where(action_type: UserAction::REPLY, target_post_id: reply.id).first
      expect(post_action).to be_present

      PostDestroyer.new(moderator, reply).destroy

      # User Action is removed
      post_action = author.user_actions.where(action_type: UserAction::REPLY, target_post_id: reply.id).first
      expect(post_action).to be_blank

      PostDestroyer.new(moderator, reply).recover

      # On recovery, the user action is recreated
      post_action = author.user_actions.where(action_type: UserAction::REPLY, target_post_id: reply.id).first
      expect(post_action).to be_present
    end

    describe "post_count recovery" do
      before do
        post
        @user = post.user
        @reply = create_post(topic: post.topic, user: @user)
        expect(@user.user_stat.post_count).to eq(1)
      end

      context "recovered by user" do
        it "should increment the user's post count" do
          PostDestroyer.new(@user, @reply).destroy
          expect(@user.user_stat.topic_count).to eq(1)
          expect(@user.user_stat.post_count).to eq(1)

          PostDestroyer.new(@user, @reply.reload).recover
          expect(@user.user_stat.topic_count).to eq(1)
          expect(@user.reload.user_stat.post_count).to eq(1)

          expect(UserAction.where(target_topic_id: post.topic_id, action_type: UserAction::NEW_TOPIC).count).to eq(1)
          expect(UserAction.where(target_topic_id: post.topic_id, action_type: UserAction::REPLY).count).to eq(1)
        end
      end

      context "recovered by admin" do
        it "should increment the user's post count" do
          PostDestroyer.new(moderator, @reply).destroy
          expect(@user.reload.user_stat.topic_count).to eq(1)
          expect(@user.user_stat.post_count).to eq(0)

          PostDestroyer.new(admin, @reply).recover
          expect(@user.reload.user_stat.topic_count).to eq(1)
          expect(@user.user_stat.post_count).to eq(1)

          PostDestroyer.new(moderator, post).destroy
          expect(@user.reload.user_stat.topic_count).to eq(0)
          expect(@user.user_stat.post_count).to eq(0)

          PostDestroyer.new(admin, post).recover
          expect(@user.reload.user_stat.topic_count).to eq(1)
          expect(@user.user_stat.post_count).to eq(1)

          expect(UserAction.where(target_topic_id: post.topic_id, action_type: UserAction::NEW_TOPIC).count).to eq(1)
          expect(UserAction.where(target_topic_id: post.topic_id, action_type: UserAction::REPLY).count).to eq(1)
        end
      end
    end
  end

  describe "recovery and post actions" do
    let(:codinghorror) { Fabricate(:coding_horror) }
    let!(:like) { PostAction.act(codinghorror, post, PostActionType.types[:like]) }
    let!(:another_like) { PostAction.act(moderator, post, PostActionType.types[:like]) }

    it "restores public post actions" do
      PostDestroyer.new(moderator, post).destroy
      expect(PostAction.exists?(id: like.id)).to eq(false)

      PostDestroyer.new(moderator, post).recover
      expect(PostAction.exists?(id: like.id)).to eq(true)
    end

    it "does not recover previously-deleted actions" do
      PostAction.remove_act(codinghorror, post, PostActionType.types[:like])
      expect(PostAction.exists?(id: like.id)).to eq(false)

      PostDestroyer.new(moderator, post).destroy
      PostDestroyer.new(moderator, post).recover
      expect(PostAction.exists?(id: another_like.id)).to eq(true)
      expect(PostAction.exists?(id: like.id)).to eq(false)
    end

    it "updates post like count" do
      PostDestroyer.new(moderator, post).destroy
      PostDestroyer.new(moderator, post).recover
      post.reload
      expect(post.like_count).to eq(2)
      expect(post.custom_fields["deleted_public_actions"]).to be_nil
    end
  end

  describe 'basic destroying' do
    it "as the creator of the post, doesn't delete the post" do
      begin
        post2 = create_post
        user_stat = post2.user.user_stat

        called = 0
        topic_destroyed = -> (topic, user) do
          expect(topic).to eq(post2.topic)
          expect(user).to eq(post2.user)
          called += 1
        end

        DiscourseEvent.on(:topic_destroyed, &topic_destroyed)

        @orig = post2.cooked
        # Guardian.new(post2.user).can_delete_post?(post2) == false
        PostDestroyer.new(post2.user, post2).destroy
        post2.reload

        expect(post2.deleted_at).to be_blank
        expect(post2.deleted_by).to be_blank
        expect(post2.user_deleted).to eq(true)
        expect(post2.raw).to eq(I18n.t('js.post.deleted_by_author', count: 24))
        expect(post2.version).to eq(2)
        expect(called).to eq(1)
        expect(user_stat.reload.post_count).to eq(0)
        expect(user_stat.reload.topic_count).to eq(1)

        called = 0
        topic_recovered = -> (topic, user) do
          expect(topic).to eq(post2.topic)
          expect(user).to eq(post2.user)
          called += 1
        end

        DiscourseEvent.on(:topic_recovered, &topic_recovered)

        # lets try to recover
        PostDestroyer.new(post2.user, post2).recover
        post2.reload
        expect(post2.version).to eq(3)
        expect(post2.user_deleted).to eq(false)
        expect(post2.cooked).to eq(@orig)
        expect(called).to eq(1)
        expect(user_stat.reload.post_count).to eq(0)
        expect(user_stat.reload.topic_count).to eq(1)
      ensure
        DiscourseEvent.off(:topic_destroyed, &topic_destroyed)
        DiscourseEvent.off(:topic_recovered, &topic_recovered)
      end
    end

    it "when topic is destroyed, it updates user_stats correctly" do
      SiteSetting.min_topic_title_length = 5
      post.topic.update_column(:title, "xyz")

      user1 = post.user
      user2 = Fabricate(:user)
      reply = create_post(topic_id: post.topic_id, user: user2)
      reply2 = create_post(topic_id: post.topic_id, user: user1)
      expect(user1.user_stat.topic_count).to eq(1)
      expect(user1.user_stat.post_count).to eq(1)
      expect(user2.user_stat.topic_count).to eq(0)
      expect(user2.user_stat.post_count).to eq(1)

      PostDestroyer.new(Fabricate(:admin), post).destroy
      user1.reload
      user2.reload
      expect(user1.user_stat.topic_count).to eq(0)
      expect(user1.user_stat.post_count).to eq(0)
      expect(user2.user_stat.topic_count).to eq(0)
      expect(user2.user_stat.post_count).to eq(0)
    end

    it "accepts a delete_removed_posts_after option" do
      SiteSetting.delete_removed_posts_after = 0

      PostDestroyer.new(post.user, post, delete_removed_posts_after: 1).destroy

      post.reload

      expect(post.deleted_at).to eq(nil)
      expect(post.user_deleted).to eq(true)

      expect(post.raw).to eq(I18n.t('js.post.deleted_by_author', count: 1))
    end

    context "as a moderator" do
      it "deletes the post" do
        author = post.user
        reply = create_post(topic_id: post.topic_id, user: author)

        post_count = author.post_count
        history_count = UserHistory.count

        PostDestroyer.new(moderator, reply).destroy

        expect(reply.deleted_at).to be_present
        expect(reply.deleted_by).to eq(moderator)

        author.reload
        expect(author.post_count).to eq(post_count - 1)
        expect(UserHistory.count).to eq(history_count + 1)
      end
    end

    context "as an admin" do
      it "deletes the post" do
        PostDestroyer.new(admin, post).destroy
        expect(post.deleted_at).to be_present
        expect(post.deleted_by).to eq(admin)
      end

      it "updates the user's topic_count for first post" do
        author = post.user
        expect {
          PostDestroyer.new(admin, post).destroy
          author.reload
        }.to change { author.topic_count }.by(-1)
        expect(author.user_stat.post_count).to eq(0)
      end

      it "updates the user's post_count for reply" do
        author = post.user
        reply = create_post(topic: post.topic, user: author)
        expect {
          PostDestroyer.new(admin, reply).destroy
          author.reload
        }.to change { author.post_count }.by(-1)
        expect(author.user_stat.topic_count).to eq(1)
      end

      it "doesn't count whispers" do
        user_stat = admin.user_stat
        whisper = PostCreator.new(
          admin,
          topic_id: post.topic.id,
          reply_to_post_number: 1,
          post_type: Post.types[:whisper],
          raw: 'this is a whispered reply'
        ).create
        expect(user_stat.reload.post_count).to eq(0)
        expect {
          PostDestroyer.new(admin, whisper).destroy
        }.to_not change { user_stat.reload.post_count }
      end
    end

  end

  context 'private message' do
    let(:author) { Fabricate(:user) }
    let(:private_message) { Fabricate(:private_message_topic, user: author) }
    let!(:first_post) { Fabricate(:post, topic: private_message, user: author) }
    let!(:second_post) { Fabricate(:post, topic: private_message, user: author, post_number: 2) }

    it "doesn't update post_count for a reply" do
      expect {
        PostDestroyer.new(admin, second_post).destroy
        author.reload
      }.to_not change { author.post_count }

      expect {
        PostDestroyer.new(admin, second_post).recover
      }.to_not change { author.post_count }
    end

    it "doesn't update topic_count for first post" do
      expect {
        PostDestroyer.new(admin, first_post).destroy
        author.reload
      }.to_not change { author.topic_count }
      expect(author.post_count).to eq(0) # also unchanged
    end

    it 'triggers the extensibility events' do
      events = DiscourseEvent.track_events { PostDestroyer.new(admin, first_post).destroy }.last(2)

      expect(events[0][:event_name]).to eq(:post_destroyed)
      expect(events[0][:params].first).to eq(first_post)

      expect(events[1][:event_name]).to eq(:topic_destroyed)
      expect(events[1][:params].first).to eq(first_post.topic)
    end
  end

  context 'deleting the second post in a topic' do

    let(:user) { Fabricate(:user) }
    let!(:post) { create_post(user: user) }
    let(:topic) { post.topic }
    let(:second_user) { Fabricate(:coding_horror) }
    let!(:second_post) { create_post(topic: topic, user: second_user) }

    before do
      PostDestroyer.new(moderator, second_post).destroy
      topic.reload
    end

    it 'resets the last_poster_id back to the OP' do
      expect(topic.last_post_user_id).to eq(user.id)
    end

    it 'resets the last_posted_at back to the OP' do
      expect(topic.last_posted_at.to_i).to eq(post.created_at.to_i)
    end

    it 'resets the highest_post_number' do
      expect(topic.highest_post_number).to eq(post.post_number)
    end

    context 'topic_user' do

      let(:topic_user) { second_user.topic_users.find_by(topic_id: topic.id) }

      it 'clears the posted flag for the second user' do
        expect(topic_user.posted?).to eq(false)
      end

      it "sets the second user's last_read_post_number back to 1" do
        expect(topic_user.last_read_post_number).to eq(1)
      end

      it "sets the second user's last_read_post_number back to 1" do
        expect(topic_user.highest_seen_post_number).to eq(1)
      end
    end
  end

  context "deleting a post belonging to a deleted topic" do
    let!(:topic) { post.topic }
    let(:author) { post.user }

    before do
      topic.trash!(admin)
      post.reload
    end

    context "as a moderator" do
      before do
        PostDestroyer.new(moderator, post).destroy
      end

      it "deletes the post" do
        expect(post.deleted_at).to be_present
        expect(post.deleted_by).to eq(moderator)
        expect(author.user_stat.post_count).to eq(0)
      end
    end

    context "as an admin" do
      subject { PostDestroyer.new(admin, post).destroy }

      it "deletes the post" do
        subject
        expect(post.deleted_at).to be_present
        expect(post.deleted_by).to eq(admin)
      end

      it "creates a new user history entry" do
        expect { subject }.to change { UserHistory.count }.by(1)
      end

      it 'triggers a extensibility event' do
        events = DiscourseEvent.track_events { subject }

        expect(events[0][:event_name]).to eq(:post_destroyed)
        expect(events[0][:params].first).to eq(post)
      end
    end
  end

  context "deleting a reply belonging to a deleted topic" do
    let!(:topic) { post.topic }
    let!(:reply) { create_post(topic_id: topic.id, user: post.user) }
    let(:author) { reply.user }

    before do
      topic.trash!(admin)
      post.reload
      reply.reload
    end

    context "as a moderator" do
      subject { PostDestroyer.new(moderator, reply).destroy }

      it "deletes the reply" do
        subject
        expect(reply.deleted_at).to be_present
        expect(reply.deleted_by).to eq(moderator)
      end

      it "doesn't decrement post_count again" do
        expect { subject }.to_not change { author.user_stat.post_count }
      end
    end

    context "as an admin" do
      subject { PostDestroyer.new(admin, reply).destroy }

      it "deletes the post" do
        subject
        expect(reply.deleted_at).to be_present
        expect(reply.deleted_by).to eq(admin)
      end

      it "doesn't decrement post_count again" do
        expect { subject }.to_not change { author.user_stat.post_count }
      end

      it "creates a new user history entry" do
        expect { subject }.to change { UserHistory.count }.by(1)
      end
    end
  end

  describe 'after delete' do

    let!(:coding_horror) { Fabricate(:coding_horror) }
    let!(:post) { Fabricate(:post, raw: "Hello @CodingHorror") }

    it "should feature the users again (in case they've changed)" do
      Jobs.expects(:enqueue).with(:feature_topic_users, has_entries(topic_id: post.topic_id))
      PostDestroyer.new(moderator, post).destroy
    end

    describe 'with a reply' do

      let!(:reply) { Fabricate(:basic_reply, user: coding_horror, topic: post.topic) }
      let!(:post_reply) { PostReply.create(post_id: post.id, reply_id: reply.id) }

      it 'changes the post count of the topic' do
        post.reload
        expect {
          PostDestroyer.new(moderator, reply).destroy
          post.topic.reload
        }.to change(post.topic, :posts_count).by(-1)
      end

      it 'lowers the reply_count when the reply is deleted' do
        expect {
          PostDestroyer.new(moderator, reply).destroy
        }.to change(post.post_replies, :count).by(-1)
      end

      it 'should increase the post_number when there are deletion gaps' do
        PostDestroyer.new(moderator, reply).destroy
        p = Fabricate(:post, user: post.user, topic: post.topic)
        expect(p.post_number).to eq(3)
      end

    end

  end

  context '@mentions' do
    it 'removes notifications when deleted' do
      SiteSetting.queue_jobs = false
      user = Fabricate(:evil_trout)
      post = create_post(raw: 'Hello @eviltrout')
      expect {
        PostDestroyer.new(Fabricate(:moderator), post).destroy
      }.to change(user.notifications, :count).by(-1)
    end
  end

  describe "post actions" do
    let(:second_post) { Fabricate(:post, topic_id: post.topic_id) }
    let!(:bookmark) { PostAction.act(moderator, second_post, PostActionType.types[:bookmark]) }
    let!(:flag) { PostAction.act(moderator, second_post, PostActionType.types[:off_topic]) }

    before do
      SiteSetting.queue_jobs = false
    end

    it "should delete public post actions and agree with flags" do
      second_post.expects(:update_flagged_posts_count)

      PostDestroyer.new(moderator, second_post).destroy

      expect(PostAction.find_by(id: bookmark.id)).to eq(nil)

      off_topic = PostAction.find_by(id: flag.id)
      expect(off_topic).not_to eq(nil)
      expect(off_topic.agreed_at).not_to eq(nil)

      second_post.reload
      expect(second_post.bookmark_count).to eq(0)
      expect(second_post.off_topic_count).to eq(1)

      notification = second_post.user.notifications.where(notification_type: Notification.types[:private_message]).last
      expect(notification).to be_present
      expect(notification.topic.title).to eq(I18n.t('system_messages.flags_agreed_and_post_deleted.subject_template'))
    end

    it "should not send the flags_agreed_and_post_deleted message if it was deleted by system" do
      second_post.expects(:update_flagged_posts_count)
      PostDestroyer.new(Discourse.system_user, second_post).destroy
      expect(
        Topic.where(title: I18n.t('system_messages.flags_agreed_and_post_deleted.subject_template')).exists?
      ).to eq(false)
    end

    it "should not send the flags_agreed_and_post_deleted message if it was deleted by author" do
      SiteSetting.delete_removed_posts_after = 0
      second_post.expects(:update_flagged_posts_count)
      PostDestroyer.new(second_post.user, second_post).destroy
      expect(
        Topic.where(title: I18n.t('system_messages.flags_agreed_and_post_deleted.subject_template')).exists?
      ).to eq(false)
    end

    it "should not send the flags_agreed_and_post_deleted message if flags were deferred" do
      second_post.expects(:update_flagged_posts_count)
      PostAction.defer_flags!(second_post, moderator)
      second_post.reload
      PostDestroyer.new(moderator, second_post).destroy
      expect(
        Topic.where(title: I18n.t('system_messages.flags_agreed_and_post_deleted.subject_template')).exists?
      ).to eq(false)
    end

    it "should set the deleted_public_actions custom field" do
      PostDestroyer.new(moderator, second_post).destroy
      expect(second_post.custom_fields["deleted_public_actions"]).to eq("#{bookmark.id}")
    end
  end

  describe "user actions" do
    let(:codinghorror) { Fabricate(:coding_horror) }
    let(:second_post) { Fabricate(:post, topic_id: post.topic_id) }

    def create_user_action(action_type)
      UserAction.log_action!(action_type: action_type,
                             user_id: codinghorror.id,
                             acting_user_id: codinghorror.id,
                             target_topic_id: second_post.topic_id,
                             target_post_id: second_post.id)
    end

    it "should delete the user actions" do
      bookmark = create_user_action(UserAction::BOOKMARK)
      like = create_user_action(UserAction::LIKE)

      PostDestroyer.new(moderator, second_post).destroy

      expect(UserAction.find_by(id: bookmark.id)).to be_nil
      expect(UserAction.find_by(id: like.id)).to be_nil
    end
  end

  describe 'topic links' do
    let!(:first_post)  { Fabricate(:post) }
    let!(:topic)       { first_post.topic }
    let!(:second_post) { Fabricate(:post_with_external_links, topic: topic) }

    before { TopicLink.extract_from(second_post) }

    it 'should destroy the topic links when moderator destroys the post' do
      PostDestroyer.new(moderator, second_post.reload).destroy
      expect(topic.topic_links.count).to eq(0)
    end

    it 'should destroy the topic links when the user destroys the post' do
      PostDestroyer.new(second_post.user, second_post.reload).destroy
      expect(topic.topic_links.count).to eq(0)
    end
  end

end