diff --git a/lib/zip.rb b/lib/zip.rb
index c3a6ed5e..fa382376 100644
--- a/lib/zip.rb
+++ b/lib/zip.rb
@@ -1,7 +1,6 @@
 require 'delegate'
 require 'singleton'
 require 'tempfile'
-require 'tmpdir'
 require 'fileutils'
 require 'stringio'
 require 'zlib'
diff --git a/lib/zip/streamable_stream.rb b/lib/zip/streamable_stream.rb
index 2a4bf507..642ddae2 100644
--- a/lib/zip/streamable_stream.rb
+++ b/lib/zip/streamable_stream.rb
@@ -2,12 +2,7 @@ module Zip
   class StreamableStream < DelegateClass(Entry) # nodoc:all
     def initialize(entry)
       super(entry)
-      dirname = if zipfile.is_a?(::String)
-                  ::File.dirname(zipfile)
-                else
-                  nil
-                end
-      @temp_file = Tempfile.new(::File.basename(name), dirname)
+      @temp_file = Tempfile.new(::File.basename(name))
       @temp_file.binmode
     end
 
diff --git a/test/test_helper.rb b/test/test_helper.rb
index ddeba58b..6d11af6c 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -2,6 +2,7 @@
 require 'minitest/autorun'
 require 'minitest/unit'
 require 'fileutils'
+require 'tmpdir'
 require 'digest/sha1'
 require 'zip'
 require 'gentestfiles'