Windows: Use Unicode aware WinAPI function for ENV[]=

This only makes a difference when setting an empty value to a Unicode key.

1 files changed, 10 insertions, 0 deletions

diff --git a/test/ruby/test_env.rb b/test/ruby/test_env.rb
index 4b5f18e7bb..74f4750b13 100644
--- a/test/ruby/test_env.rb
+++ b/test/ruby/test_env.rb
@@ -1485,5 +1485,15 @@ class TestEnv < Test::Unit::TestCase
     ensure
       ENV["test"] = test
     end
+
+    def test_utf8_empty
+      key = "VAR\u{e5 e1 e2 e4 e3 101 3042}"
+      ENV[key] = "x"
+      assert_equal "x", ENV[key]
+      ENV[key] = ""
+      assert_equal "", ENV[key]
+      ENV[key] = nil
+      assert_nil ENV[key]
+    end
   end
 end