hash.c: add compact and compact! methods

* hash.c (rb_hash_compact, rb_hash_compact_bang): Removes nil
  values from the original hash, to port Active Support behavior.
  [Feature #11818]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56414 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 0 deletions

diff --git a/test/ruby/test_hash.rb b/test/ruby/test_hash.rb
index edc0eeebee..7720b6098e 100644
--- a/test/ruby/test_hash.rb
+++ b/test/ruby/test_hash.rb
@@ -354,6 +354,14 @@ class TestHash < Test::Unit::TestCase
     assert_equal({1=>2,3=>4,5=>6}, h.keep_if{true})
   end
 
+  def test_compact
+    h = @cls[a: 1, b: nil, c: false, d: true, e: nil]
+    assert_equal({a: 1, c: false, d: true}, h.compact)
+    assert_equal({a: 1, b: nil, c: false, d: true, e: nil}, h)
+    h.compact!
+    assert_equal({a: 1, c: false, d: true}, h)
+  end
+
   def test_dup
     for taint in [ false, true ]
       for frozen in [ false, true ]