FEATURE: automatically hide posts made by TL0 users when flagged by a TL3 user

app/models/post.rb

@@ -62,7 +62,12 @@ class Post < ActiveRecord::Base
   delegate :username, to: :user
 
   def self.hidden_reasons
-    @hidden_reasons ||= Enum.new(:flag_threshold_reached, :flag_threshold_reached_again, :new_user_spam_threshold_reached)
+    @hidden_reasons ||= Enum.new(
+      :flag_threshold_reached,
+      :flag_threshold_reached_again,
+      :new_user_spam_threshold_reached,
+      :flagged_by_tl3_user
+    )
   end
 
   def self.types

app/models/post_action.rb

@@ -372,7 +372,7 @@ class PostAction < ActiveRecord::Base
 
   def enforce_rules
     post = Post.with_deleted.where(id: post_id).first
-    PostAction.auto_hide_if_needed(post, post_action_type_key)
+    PostAction.auto_hide_if_needed(user, post, post_action_type_key)
     SpamRulesEnforcer.enforce!(post.user) if post_action_type_key == :spam
   end
 
@@ -382,10 +382,16 @@ class PostAction < ActiveRecord::Base
     end
   end
 
-  def self.auto_hide_if_needed(post, post_action_type)
+  def self.auto_hide_if_needed(acting_user, post, post_action_type)
     return if post.hidden
 
-    if PostActionType.auto_action_flag_types.include?(post_action_type) &&
+    if post_action_type == :spam &&
+       acting_user.trust_level == TrustLevel[3] &&
+       post.user.trust_level == TrustLevel[0]
+
+       hide_post!(post, post_action_type, Post.hidden_reasons[:flagged_by_tl3_user])
+
+    elsif PostActionType.auto_action_flag_types.include?(post_action_type) &&
           SiteSetting.flags_required_to_hide_post > 0
 
       old_flags, new_flags = PostAction.flag_counts_for(post.id)

spec/models/post_action_spec.rb

@@ -326,6 +326,21 @@ describe PostAction do
       post.topic.visible.should == false
     end
 
+    it "hide tl0 posts that are flagged as spam by a tl3 user" do
+      newuser = Fabricate(:newuser)
+      post = create_post(user: newuser)
+
+      Discourse.stubs(:site_contact_user).returns(admin)
+
+      PostAction.act(Fabricate(:leader), post, PostActionType.types[:spam])
+
+      post.reload
+
+      post.hidden.should == true
+      post.hidden_at.should be_present
+      post.hidden_reason_id.should == Post.hidden_reasons[:flagged_by_tl3_user]
+    end
+
     it "can flag the topic instead of a post" do
       post1 = create_post
       post2 = create_post(topic: post1.topic)