From 981299e3d27e4554eebaea6a9268a9530461cc13 Mon Sep 17 00:00:00 2001
From: Ryuta Kamizono <kamipo@gmail.com>
Date: Sun, 10 May 2020 06:14:29 +0900
Subject: [PATCH] Eager generate relation methods if a method is on `Kernel`

Follow up of #34122.

Relation method call is relying on method_missing, but if `Kernel` has
the same named method (e.g. `open`, etc), it will invoke Kernel's method
since method_missing is not happened.

To prevent that, eager generate relation methods if a method is the same
name on `Kernel`.

Fixes #39195.
---
 activerecord/lib/active_record/scoping/named.rb | 4 ++++
 activerecord/test/cases/relations_test.rb       | 2 ++
 activerecord/test/models/reply.rb               | 4 ++++
 activerecord/test/models/topic.rb               | 1 +
 4 files changed, 11 insertions(+)

diff --git a/activerecord/lib/active_record/scoping/named.rb b/activerecord/lib/active_record/scoping/named.rb
index 116a27e7d0..46cfb2ea21 100644
--- a/activerecord/lib/active_record/scoping/named.rb
+++ b/activerecord/lib/active_record/scoping/named.rb
@@ -198,6 +198,10 @@ module ActiveRecord
         end
 
         private
+          def singleton_method_added(name)
+            generate_relation_method(name) if Kernel.respond_to?(name)
+          end
+
           def valid_scope_name?(name)
             if respond_to?(name, true) && logger
               logger.warn "Creating scope :#{name}. " \
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index d8d99637c2..d5a2f896f6 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -2119,6 +2119,8 @@ class RelationTest < ActiveRecord::TestCase
     sub_accounts = SubAccount.all
     assert_equal [accounts(:signals37)], sub_accounts.open
     assert_equal [accounts(:signals37)], sub_accounts.available
+
+    assert_equal [topics(:second)], topics(:first).open_replies
   end
 
   def test_where_with_take_memoization
diff --git a/activerecord/test/models/reply.rb b/activerecord/test/models/reply.rb
index f6ab9c8a8f..074a51f3df 100644
--- a/activerecord/test/models/reply.rb
+++ b/activerecord/test/models/reply.rb
@@ -9,6 +9,10 @@ class Reply < Topic
   has_many :silly_unique_replies, dependent: :destroy, foreign_key: "parent_id"
 
   scope :ordered, -> { Reply.order(:id) }
+
+  def self.open
+    approved
+  end
 end
 
 class SillyReply < Topic
diff --git a/activerecord/test/models/topic.rb b/activerecord/test/models/topic.rb
index a3a0f570ae..19fb704d12 100644
--- a/activerecord/test/models/topic.rb
+++ b/activerecord/test/models/topic.rb
@@ -42,6 +42,7 @@ class Topic < ActiveRecord::Base
 
   has_many :replies, dependent: :destroy, foreign_key: "parent_id", autosave: true
   has_many :approved_replies, -> { approved }, class_name: "Reply", foreign_key: "parent_id", counter_cache: "replies_count"
+  has_many :open_replies, -> { open }, class_name: "Reply", foreign_key: "parent_id"
 
   has_many :unique_replies, dependent: :destroy, foreign_key: "parent_id"
   has_many :silly_unique_replies, dependent: :destroy, foreign_key: "parent_id"