HashWithIndifferentAccess#select working as intended

Before this commit, #reject returned a HashWithIndifferentAccess,
whereas #select returned a Hash. Now #select also returns a
HashWithIndifferentAccess.

activesupport/lib/active_support/hash_with_indifferent_access.rb

@@ -227,6 +227,10 @@ def symbolize_keys; to_hash.symbolize_keys! end
     def deep_symbolize_keys; to_hash.deep_symbolize_keys end
     def to_options!; self end
 
+    def select(*args, &block)
+      dup.select!(*args, &block)
+    end
+
     # Convert to a regular hash with string keys.
     def to_hash
       _new_hash= {}

activesupport/test/core_ext/hash_ext_test.rb

@@ -480,6 +480,36 @@ def test_indifferent_deleting
     assert_equal hash.delete('a'), nil
   end
 
+  def test_indifferent_select
+    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).select {|k,v| v == 1}
+
+    assert_equal({ 'a' => 1 }, hash)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
+  end
+
+  def test_indifferent_select_bang
+    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
+    indifferent_strings.select! {|k,v| v == 1}
+
+    assert_equal({ 'a' => 1 }, indifferent_strings)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
+  end
+
+  def test_indifferent_reject
+    hash = ActiveSupport::HashWithIndifferentAccess.new(@strings).reject {|k,v| v != 1}
+
+    assert_equal({ 'a' => 1 }, hash)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, hash
+  end
+
+  def test_indifferent_reject_bang
+    indifferent_strings = ActiveSupport::HashWithIndifferentAccess.new(@strings)
+    indifferent_strings.reject! {|k,v| v != 1}
+
+    assert_equal({ 'a' => 1 }, indifferent_strings)
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, indifferent_strings
+  end
+
   def test_indifferent_to_hash
     # Should convert to a Hash with String keys.
     assert_equal @strings, @mixed.with_indifferent_access.to_hash