chdir before globbing so that we don't need to escape directory names.

fixes #5521

railties/lib/rails/paths.rb

@@ -157,7 +157,25 @@ def expanded
           path = File.expand_path(p, @root.path)
 
           if @glob
-            result.concat Dir[File.join(path, @glob)].sort
+            if File.directory? path
+              result.concat expand_dir(path, @glob)
+            else
+              # FIXME: I think we can remove this branch, but I'm not sure.
+              # Say the filesystem has this file:
+              #
+              #   /tmp/foobar
+              #
+              # and someone adds this path:
+              #
+              #   /tmp/foo
+              #
+              # with a glob of "*", then this function will return
+              #
+              #   /tmp/foobar
+              #
+              # We need to figure out if that is desired behavior.
+              result.concat expand_file(path, @glob)
+            end
           else
             result << path
           end
@@ -177,6 +195,17 @@ def existent_directories
       end
 
       alias to_a expanded
+
+      private
+      def expand_file(path, glob)
+        Dir[File.join(path, glob)].sort
+      end
+
+      def expand_dir(path, glob)
+        Dir.chdir(path) do
+          Dir.glob(@glob).map { |file| File.join path, file }.sort
+        end
+      end
     end
   end
 end