allow Array.penultimate and Array.antepenultiate access methods

2 files changed, 16 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/core_ext/array/access.rb b/activesupport/lib/active_support/core_ext/array/access.rb
index 3177d8498e..e413acddc5 100644
--- a/activesupport/lib/active_support/core_ext/array/access.rb
+++ b/activesupport/lib/active_support/core_ext/array/access.rb
@@ -73,4 +73,18 @@ class Array
   def forty_two
     self[41]
   end
+
+  # Equal to <tt>self[-3]</tt>.
+  #
+  #   %w( a b c d e ).antepenultimate # => "c"
+  def antepenultimate
+    self[-3]
+  end
+
+  # Equal to <tt>self[-2]</tt>.
+  #
+  #   %w( a b c d e ).penultimate # => "d"
+  def penultimate
+    self[-2]
+  end
 end
diff --git a/activesupport/test/core_ext/array/access_test.rb b/activesupport/test/core_ext/array/access_test.rb
index 3f1e0c4cb4..d7a3fb56c2 100644
--- a/activesupport/test/core_ext/array/access_test.rb
+++ b/activesupport/test/core_ext/array/access_test.rb
@@ -26,6 +26,8 @@ class AccessTest < ActiveSupport::TestCase
     assert_equal array[3], array.fourth
     assert_equal array[4], array.fifth
     assert_equal array[41], array.forty_two
+    assert_equal array[-3], array.antepenultimate
+    assert_equal array[-2], array.penultimate
   end
 
   def test_without