When must_be_following_dm is on, only notify if recipient dm'ed user (#6283)

* When must_be_following_dm is on, only notify if recipient dm'ed user
Currently, when must_be_following_dm is on, if a user sends a direct
message replying to any status from the recipient, the recipient gets a
notification. This should not be the case, as if the recipient posted
something publicly this can be used to spam their notifications.

* Refactor replied_to_status_is_direct_message?
Following suggestion in PR

1 files changed, 10 insertions, 1 deletions

diff --git a/spec/services/notify_service_spec.rb b/spec/services/notify_service_spec.rb
index eb6210a1e..abe557cf3 100644
--- a/spec/services/notify_service_spec.rb
+++ b/spec/services/notify_service_spec.rb
@@ -62,10 +62,19 @@ RSpec.describe NotifyService do
         is_expected.to_not change(Notification, :count)
       end
 
-      context 'if the message chain initiated by recipient' do
+      context 'if the message chain initiated by recipient, but is not direct message' do
         let(:reply_to) { Fabricate(:status, account: recipient) }
         let(:activity) { Fabricate(:mention, account: recipient, status: Fabricate(:status, account: sender, visibility: :direct, thread: reply_to)) }
 
+        it 'does not notify' do
+          is_expected.to_not change(Notification, :count)
+        end
+      end
+
+      context 'if the message chain initiated by recipient and is direct message' do
+        let(:reply_to) { Fabricate(:status, account: recipient, visibility: :direct) }
+        let(:activity) { Fabricate(:mention, account: recipient, status: Fabricate(:status, account: sender, visibility: :direct, thread: reply_to)) }
+
         it 'does notify' do
           is_expected.to change(Notification, :count)
         end