diff --git a/test/open-uri/test_ftp.rb b/test/open-uri/test_ftp.rb
index 9698ff2777ed89..0b3bafb9e0341a 100644
--- a/test/open-uri/test_ftp.rb
+++ b/test/open-uri/test_ftp.rb
@@ -8,10 +8,10 @@ def with_env(h)
     begin
       old = {}
       h.each_key {|k| old[k] = ENV[k] }
-      h.each {|k, v| ENV[k] = v }
+      ENV.update(h)
       yield
     ensure
-      h.each_key {|k| ENV[k] = old[k] }
+      ENV.update(old)
     end
   end
 
diff --git a/test/open-uri/test_proxy.rb b/test/open-uri/test_proxy.rb
index a36a63f21f2c80..0cc711a0f3cee3 100644
--- a/test/open-uri/test_proxy.rb
+++ b/test/open-uri/test_proxy.rb
@@ -11,10 +11,10 @@ def with_env(h)
     begin
       old = {}
       h.each_key {|k| old[k] = ENV[k] }
-      h.each {|k, v| ENV[k] = v }
+      ENV.update(h)
       yield
     ensure
-      h.each_key {|k| ENV[k] = old[k] }
+      ENV.update(old)
     end
   end