3 files changed, 31 insertions, 0 deletions
diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 6312960819..305dc01b22 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Uniqueness validation with out of range value fixed
+
+    *Andrey Voronkov*
+
 *   MySQL: `:charset` and `:collation` support for string and text columns.
 
     Example:
diff --git a/activerecord/lib/active_record/validations/uniqueness.rb b/activerecord/lib/active_record/validations/uniqueness.rb
index 9be4b10a55..5106f4e127 100644
--- a/activerecord/lib/active_record/validations/uniqueness.rb
+++ b/activerecord/lib/active_record/validations/uniqueness.rb
@@ -76,6 +76,8 @@ module ActiveRecord
           klass.connection.case_sensitive_comparison(table, attribute, column, value)
         end
         klass.unscoped.where(comparison)
+      rescue RangeError
+        klass.none
       end
 
       def scope_relation(record, table, relation)
diff --git a/activerecord/test/cases/validations/uniqueness_validation_test.rb b/activerecord/test/cases/validations/uniqueness_validation_test.rb
index 062bc733f9..778697e225 100644
--- a/activerecord/test/cases/validations/uniqueness_validation_test.rb
+++ b/activerecord/test/cases/validations/uniqueness_validation_test.rb
@@ -34,6 +34,19 @@ class TopicWithUniqEvent < Topic
   validates :event, uniqueness: true
 end
 
+class BigIntTest < ActiveRecord::Base
+  PG_MAX_INTEGER = 2147483647
+  self.table_name = 'cars'
+  validates :engines_count, uniqueness: true, inclusion: { in: 0..PG_MAX_INTEGER }
+end
+
+class BigIntReverseTest < ActiveRecord::Base
+  PG_MAX_INTEGER = 2147483647
+  self.table_name = 'cars'
+  validates :engines_count, inclusion: { in: 0..PG_MAX_INTEGER }
+  validates :engines_count, uniqueness: true
+end
+
 class UniquenessValidationTest < ActiveRecord::TestCase
   fixtures :topics, 'warehouse-things'
 
@@ -86,6 +99,18 @@ class UniquenessValidationTest < ActiveRecord::TestCase
     assert t2.errors[:title]
   end
 
+  if current_adapter? :PostgreSQLAdapter
+    def test_validate_uniqueness_when_integer_out_of_range
+      entry = BigIntTest.create(engines_count: (BigIntTest::PG_MAX_INTEGER + 1))
+      assert_equal entry.errors[:engines_count], ['is not included in the list']
+    end
+
+    def test_validate_uniqueness_when_integer_out_of_range_show_order_does_not_matter
+      entry = BigIntReverseTest.create(engines_count: (BigIntTest::PG_MAX_INTEGER + 1))
+      assert_equal entry.errors[:engines_count], ['is not included in the list']
+    end
+  end
+
   def test_validates_uniqueness_with_newline_chars
     Topic.validates_uniqueness_of(:title, :case_sensitive => false)