Merge pull request #1923 from ksss/hash-enumerator-select

Hash#{select,select!} support return Enumerator

mrbgems/mruby-enumerator/test/enumerator.rb

@@ -494,6 +494,20 @@ assert 'Hash#each_value' do
   assert_equal [1,2], {a:1,b:2}.each_value.to_a.sort
 end
 
+assert 'Hash#select' do
+  h = {1=>2,3=>4,5=>6}
+  hret = h.select.with_index {|a,b| a[1] == 4}
+  assert_equal({3=>4}, hret)
+  assert_equal({1=>2,3=>4,5=>6}, h)
+end
+
+assert 'Hash#select!' do
+  h = {1=>2,3=>4,5=>6}
+  hret = h.select!.with_index {|a,b| a[1] == 4}
+  assert_equal h, hret
+  assert_equal({3=>4}, h)
+end
+
 assert 'Range#each' do
   a = (1..5)
   b = a.each