From b0be7792adf58e092b7f615ecbf3339ea70ee689 Mon Sep 17 00:00:00 2001
From: namusyaka <namusyaka@gmail.com>
Date: Fri, 17 Feb 2017 22:15:01 +0900
Subject: [PATCH] Avoid converting integer as a string into float

---
 activemodel/CHANGELOG.md                                 | 4 ++++
 activemodel/lib/active_model/validations/numericality.rb | 1 +
 .../cases/validations/numericality_validation_test.rb    | 9 +++++++++
 3 files changed, 14 insertions(+)

diff --git a/activemodel/CHANGELOG.md b/activemodel/CHANGELOG.md
index edaac8c7cde..a667e116b62 100644
--- a/activemodel/CHANGELOG.md
+++ b/activemodel/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Avoid converting integer as a string into float.
+
+    *namusyaka*
+
 *   Remove deprecated behavior that halts callbacks when the return is false.
 
     *Rafael Mendonça França*
diff --git a/activemodel/lib/active_model/validations/numericality.rb b/activemodel/lib/active_model/validations/numericality.rb
index 30a9ef472d2..995b3312451 100644
--- a/activemodel/lib/active_model/validations/numericality.rb
+++ b/activemodel/lib/active_model/validations/numericality.rb
@@ -70,6 +70,7 @@ module ActiveModel
       end
 
       def parse_raw_value_as_a_number(raw_value)
+        return raw_value.to_i if is_integer?(raw_value)
         Kernel.Float(raw_value) if raw_value !~ /\A0[xX]/
       end
 
diff --git a/activemodel/test/cases/validations/numericality_validation_test.rb b/activemodel/test/cases/validations/numericality_validation_test.rb
index a1be2de5785..c0158e075fb 100644
--- a/activemodel/test/cases/validations/numericality_validation_test.rb
+++ b/activemodel/test/cases/validations/numericality_validation_test.rb
@@ -260,6 +260,15 @@ class NumericalityValidationTest < ActiveModel::TestCase
     Person.clear_validators!
   end
 
+  def test_validates_numericality_with_exponent_number
+    base = 10_000_000_000_000_000
+    Topic.validates_numericality_of :approved, less_than_or_equal_to: base
+    topic = Topic.new
+    topic.approved = (base + 1).to_s
+
+    assert topic.invalid?
+  end
+
   def test_validates_numericality_with_invalid_args
     assert_raise(ArgumentError) { Topic.validates_numericality_of :approved, greater_than_or_equal_to: "foo" }
     assert_raise(ArgumentError) { Topic.validates_numericality_of :approved, less_than_or_equal_to: "foo" }