FEATURE: Admins should be able to view PMs of any group.

lib/topic_query.rb

@@ -434,11 +434,21 @@ class TopicQuery
 
       if type == :group
         result = result.includes(:allowed_users)
-        result = result.where("topics.id IN (SELECT topic_id FROM topic_allowed_groups
-                                              WHERE group_id IN (
-                                                  SELECT group_id FROM group_users WHERE user_id = #{user.id.to_i}) AND
-                                                         group_id IN (SELECT id FROM groups WHERE name ilike ?)
-                                             )", @options[:group_name])
+        result = result.where("
+          topics.id IN (
+            SELECT topic_id FROM topic_allowed_groups
+            WHERE (
+              group_id IN (
+                SELECT group_id
+                FROM group_users
+                WHERE user_id = #{user.id.to_i}
+                OR #{user.staff?}
+              )
+            )
+            AND group_id IN (SELECT id FROM groups WHERE name ilike ?)
+          )",
+          @options[:group_name]
+        )
       elsif type == :user
         result = result.includes(:allowed_users)
         result = result.where("topics.id IN (SELECT topic_id FROM topic_allowed_users WHERE user_id = #{user.id.to_i})")

spec/components/topic_query_spec.rb

@@ -940,4 +940,45 @@ describe TopicQuery do
       expect(topics).to contain_exactly(topic1, topic2, topic6)
     end
   end
+
+  describe '#list_private_messages_group' do
+    let(:group) { Fabricate(:group) }
+
+    let!(:group_message) do
+      Fabricate(:private_message_topic,
+        allowed_groups: [group],
+        topic_allowed_users: [
+          Fabricate.build(:topic_allowed_user, user: Fabricate(:user)),
+        ]
+      )
+    end
+
+    before do
+      group.add(creator)
+    end
+
+    it 'should return the right list for a group user' do
+      topics = TopicQuery.new(nil, group_name: group.name)
+        .list_private_messages_group(creator)
+        .topics
+
+      expect(topics).to contain_exactly(group_message)
+    end
+
+    it 'should return the right list for an admin not part of the group' do
+      topics = TopicQuery.new(nil, group_name: group.name)
+        .list_private_messages_group(Fabricate(:admin))
+        .topics
+
+      expect(topics).to contain_exactly(group_message)
+    end
+
+    it 'should return the right list for a user not part of the group' do
+      topics = TopicQuery.new(nil, group_name: group.name)
+        .list_private_messages_group(Fabricate(:user))
+        .topics
+
+      expect(topics).to eq([])
+    end
+  end
 end