Adding Hash#compact and Hash#compact! methods

  * Adding Hash#compact and Hash#compact! methods
  * Using Ruby 1.9 syntax on documentation
  * Updating guides for `Hash#compact` and `Hash#compact!` methods
  * Updating CHANGELOG for ActiveSupport
  * Removing unecessary protected method and lambda for `Hash#compact` implementations
  * Performing `Hash#compact` implementation - https://gist.github.com/tinogomes/8332883
  * fixing order position
  * Fixing typo

1 files changed, 28 insertions, 0 deletions

diff --git a/activesupport/test/core_ext/hash_ext_test.rb b/activesupport/test/core_ext/hash_ext_test.rb
index 1ee9fbf46e..40c8f03374 100644
--- a/activesupport/test/core_ext/hash_ext_test.rb
+++ b/activesupport/test/core_ext/hash_ext_test.rb
@@ -54,6 +54,8 @@ class HashExtTest < ActiveSupport::TestCase
     assert_respond_to h, :deep_stringify_keys!
     assert_respond_to h, :to_options
     assert_respond_to h, :to_options!
+    assert_respond_to h, :compact
+    assert_respond_to h, :compact!
   end
 
   def test_transform_keys
@@ -865,6 +867,32 @@ class HashExtTest < ActiveSupport::TestCase
     original.expects(:delete).never
     original.except(:a)
   end
+
+  def test_compact
+    hash_contain_nil_value = @symbols.merge(z: nil)
+    hash_with_only_nil_values = { a: nil, b: nil }
+    
+    h = hash_contain_nil_value.dup
+    assert_equal(@symbols, h.compact)
+    assert_equal(hash_contain_nil_value, h)
+    
+    h = hash_with_only_nil_values.dup
+    assert_equal({}, h.compact)
+    assert_equal(hash_with_only_nil_values, h)
+  end
+
+  def test_compact!
+    hash_contain_nil_value = @symbols.merge(z: nil)
+    hash_with_only_nil_values = { a: nil, b: nil }
+    
+    h = hash_contain_nil_value.dup
+    assert_equal(@symbols, h.compact!)
+    assert_equal(@symbols, h)
+    
+    h = hash_with_only_nil_values.dup
+    assert_equal({}, h.compact!)
+    assert_equal({}, h)
+  end
 end
 
 class IWriteMyOwnXML