reorder bind parameters when merging relations

2 files changed, 25 insertions, 1 deletions

diff --git a/activerecord/test/cases/relation_test.rb b/activerecord/test/cases/relation_test.rb
index 7862d96bd7..7c90f54343 100644
--- a/activerecord/test/cases/relation_test.rb
+++ b/activerecord/test/cases/relation_test.rb
@@ -9,6 +9,9 @@ module ActiveRecord
     fixtures :posts, :comments, :authors
 
     class FakeKlass < Struct.new(:table_name, :name)
+      def self.connection
+        Post.connection
+      end
     end
 
     def test_construction
@@ -204,6 +207,10 @@ module ActiveRecord
       def arel_table
         Post.arel_table
       end
+
+      def connection
+        Post.connection
+      end
     end
 
     def relation
@@ -295,7 +302,7 @@ module ActiveRecord
       assert_equal({foo: 'bar'}, relation.create_with_value)
     end
 
-    test 'merge!' do
+    def test_merge!
       assert relation.merge!(where: :foo).equal?(relation)
       assert_equal [:foo], relation.where_values
     end
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index b205472cf5..d0f8731b9a 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -1556,4 +1556,21 @@ class RelationTest < ActiveRecord::TestCase
     merged = left.merge(right)
     assert_equal binds, merged.bind_values
   end
+
+  def test_merging_reorders_bind_params
+    post         = Post.first
+    id_column    = Post.columns_hash['id']
+    title_column = Post.columns_hash['title']
+
+    bv = Post.connection.substitute_at id_column, 0
+
+    right  = Post.where(id: bv)
+    right.bind_values += [[id_column, post.id]]
+
+    left   = Post.where(title: bv)
+    left.bind_values += [[title_column, post.title]]
+
+    merged = left.merge(right)
+    assert_equal post, merged.first
+  end
 end