Fix for finding files by patterns that include {..,..} (#65)

lib/fakefs/file_system.rb

@@ -121,7 +121,8 @@ module FakeFS
           directories_under(dir)
         end
       else
-        dir.reject {|k,v| /\A#{pattern.gsub('?','.').gsub('*', '.*')}\Z/ !~ k }.values
+        regexp_pattern = /\A#{pattern.gsub('?','.').gsub('*', '.*').gsub(/\{(.*?)\}/) { "(#{$1.split(',').join('|')})" }}\Z/
+        dir.reject {|k,v| regexp_pattern !~ k }.values
       end
 
       if parts.empty? # we're done recursing

test/fakefs_test.rb

@@ -573,6 +573,8 @@ class FakeFSTest < Test::Unit::TestCase
     FileUtils.cp_r '/path', '/otherpath'
 
     assert_equal %w( /otherpath/foo /otherpath/foobar /path/foo /path/foobar ), Dir['/*/foo*']
+
+    assert_equal ['/path/bar', '/path/foo'], Dir['/path/{foo,bar}']
   end
 
   def test_dir_glob_handles_root