FIX: Check type of existing reviewables when new reviewable is created (#13662)

app/models/reviewable.rb

@@ -139,8 +139,8 @@ class Reviewable < ActiveRecord::Base
     )
     reviewable.created_new!
 
-    if target.blank?
-      # If there is no target there's no chance of a conflict
+    if target.blank? || !Reviewable.where(target: target, type: reviewable.type).exists?
+      # If there is no target, or no existing reviewable with matching target and type, there's no chance of a conflict
       reviewable.save!
     else
       # In this case, a reviewable might already exist for this (type, target_id) index.

spec/models/reviewable_spec.rb

@@ -78,6 +78,14 @@ RSpec.describe Reviewable, type: :model do
       expect(r1.pending?).to eq(true)
       expect(r0.pending?).to eq(false)
     end
+
+    it "will create a new reviewable when an existing reviewable exists the same target with different type" do
+      r0 = Fabricate(:reviewable_queued_post)
+      r0.perform(admin, :approve_post)
+
+      r1 = ReviewableFlaggedPost.needs_review!(created_by: admin, target: r0.target)
+      expect(r1.pending?).to eq(true)
+    end
   end
 
   context ".list_for" do