1 files changed, 39 insertions, 2 deletions
diff --git a/activesupport/test/core_ext/hash_ext_test.rb b/activesupport/test/core_ext/hash_ext_test.rb
index 86272a28c1..b2a9731578 100644
--- a/activesupport/test/core_ext/hash_ext_test.rb
+++ b/activesupport/test/core_ext/hash_ext_test.rb
@@ -60,6 +60,43 @@ class HashExtTest < Test::Unit::TestCase
     assert_equal @strings, @mixed.dup.stringify_keys!
   end
 
+  def test_symbolize_keys_for_hash_with_indifferent_access
+    assert_instance_of Hash, @symbols.with_indifferent_access.symbolize_keys
+    assert_equal @symbols, @symbols.with_indifferent_access.symbolize_keys
+    assert_equal @symbols, @strings.with_indifferent_access.symbolize_keys
+    assert_equal @symbols, @mixed.with_indifferent_access.symbolize_keys
+  end
+
+  def test_symbolize_keys_bang_for_hash_with_indifferent_access
+    assert_raise(NoMethodError) { @symbols.with_indifferent_access.dup.symbolize_keys! }
+    assert_raise(NoMethodError) { @strings.with_indifferent_access.dup.symbolize_keys! }
+    assert_raise(NoMethodError) { @mixed.with_indifferent_access.dup.symbolize_keys! }
+  end
+
+  def test_symbolize_keys_preserves_keys_that_cant_be_symbolized_for_hash_with_indifferent_access
+    assert_equal @illegal_symbols, @illegal_symbols.with_indifferent_access.symbolize_keys
+    assert_raise(NoMethodError) { @illegal_symbols.with_indifferent_access.dup.symbolize_keys! }
+  end
+
+  def test_symbolize_keys_preserves_fixnum_keys_for_hash_with_indifferent_access
+    assert_equal @fixnums, @fixnums.with_indifferent_access.symbolize_keys
+    assert_raise(NoMethodError) { @fixnums.with_indifferent_access.dup.symbolize_keys! }
+  end
+
+  def test_stringify_keys_for_hash_with_indifferent_access
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @symbols.with_indifferent_access.stringify_keys
+    assert_equal @strings, @symbols.with_indifferent_access.stringify_keys
+    assert_equal @strings, @strings.with_indifferent_access.stringify_keys
+    assert_equal @strings, @mixed.with_indifferent_access.stringify_keys
+  end
+
+  def test_stringify_keys_bang_for_hash_with_indifferent_access
+    assert_instance_of ActiveSupport::HashWithIndifferentAccess, @symbols.with_indifferent_access.dup.stringify_keys!
+    assert_equal @strings, @symbols.with_indifferent_access.dup.stringify_keys!
+    assert_equal @strings, @strings.with_indifferent_access.dup.stringify_keys!
+    assert_equal @strings, @mixed.with_indifferent_access.dup.stringify_keys!
+  end
+
   def test_indifferent_assorted
     @strings = @strings.with_indifferent_access
     @symbols = @symbols.with_indifferent_access
@@ -213,11 +250,11 @@ class HashExtTest < Test::Unit::TestCase
   def test_stringify_and_symbolize_keys_on_indifferent_preserves_hash
     h = HashWithIndifferentAccess.new
     h[:first] = 1
-    h.stringify_keys!
+    h = h.stringify_keys
     assert_equal 1, h['first']
     h = HashWithIndifferentAccess.new
     h['first'] = 1
-    h.symbolize_keys!
+    h = h.symbolize_keys
     assert_equal 1, h[:first]
   end