added tests for the Comment#pings method

Author: Oaphi

test/fixtures/comment_threads.yml

@@ -68,3 +68,9 @@ new_user_on_own_post:
   reply_count: 0
   post: new_user_question
   community: sample
+
+with_user_pings:
+  title: Pings for @#-1 and @#<%= ActiveRecord::FixtureSet.identify :standard_user %> users
+  reply_count: 1
+  post: question_one
+  community: sample

test/fixtures/comments.yml

@@ -70,3 +70,14 @@ new_user_on_own_post:
   comment_thread: new_user_on_own_post
   created_at: 2020-01-01T00:00:00.000000Z
   updated_at: 2021-01-01T00:00:00.000000Z
+
+with_user_pings:
+  user: standard_user
+  post: question_one
+  content: >
+    special ping for @#-1 user (system)
+    and for @#<%= ActiveRecord::FixtureSet.identify :standard_user %> (user)
+  community: sample
+  comment_thread: with_user_pings
+  created_at: 2020-01-01T00:00:00.000000Z
+  updated_at: 2021-01-01T00:00:00.000000Z

test/models/comment_test.rb

@@ -33,4 +33,14 @@ class CommentTest < ActiveSupport::TestCase
       assert_not Comment::USER_PING_REG_EXP.match?(mention)
     end
   end
+
+  test 'pings should correctly' do
+    std_user = users(:standard_user)
+    with_pings = comments(:with_user_pings)
+
+    pings = with_pings.pings
+
+    assert pings.include?(std_user.id)
+    assert_not pings.include?(User.system.id)
+  end
 end