diff --git a/ChangeLog b/ChangeLog
index 8a5d1c2f9e..9fdc8162b1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Jan  5 21:32:26 2016  Kuniaki IGARASHI  <igaiga@gmail.com>
+
+	* test/ruby/test_numeric.rb (test_nonzero_p): added test for String#nonzero?
+	  [fix GH-1187]
+
 Tue Jan  5 11:47:23 2016  Damir Gaynetdinov  <damir.gaynetdinov@gmail.com>
 
 	* doc/marshal.rdoc: Clarify object references example, that the
diff --git a/test/ruby/test_numeric.rb b/test/ruby/test_numeric.rb
index ad5e283152..89e11d0ff8 100644
--- a/test/ruby/test_numeric.rb
+++ b/test/ruby/test_numeric.rb
@@ -147,6 +147,18 @@ class TestNumeric < Test::Unit::TestCase
     assert_predicate(a, :zero?)
   end
 
+  def test_nonzero_p
+    a = Class.new(Numeric) do
+      def zero?; true; end
+    end.new
+    assert_nil(a.nonzero?)
+
+    a = Class.new(Numeric) do
+      def zero?; false; end
+    end.new
+    assert_equal(a, a.nonzero?)
+  end
+
   def test_positive_p
     a = Class.new(Numeric) do
       def >(x); true; end