File.join delegates to RealFile.join. Closes #31

lib/fakefs/file.rb

@@ -33,7 +33,7 @@ module FakeFS
     end
 
     def self.join(*parts)
-      parts * PATH_SEPARATOR
+      RealFile.join(parts)
     end
 
     def self.exist?(path)

test/fake/file/join_test.rb

@@ -0,0 +1,19 @@
+require "test_helper"
+
+class FileJoin < Test::Unit::TestCase
+  def setup
+    FakeFS.activate!
+  end
+
+  def teardown
+    FakeFS.deactivate!
+  end
+
+  [
+    ["a", "b"],  ["a/", "b"], ["a", "/b"], ["a/", "/b"], ["a", "/", "b"]
+  ].each_with_index do |args, i|
+    define_method "test_file_join_#{i}" do
+      assert_equal RealFile.join(args), File.join(args)
+    end
+  end
+end