How do I control REXML formatting on added elements?

Question

I am a adding a couple of simple elements to a bunch of XML files (plists). The existing XML element I am working on looks like this:

<dict>
  <key>background</key>
  <string>#FFFFFF</string>
  <key>caret</key>
  <string>#000000</string>
  <key>foreground</key>
  <string>#000000</string>
  <key>invisibles</key>
  <string>#BFBFBF</string>
  <key>lineHighlight</key>
  <string>#00000012</string>
  <key>selection</key>
  <string>#BAD6FD</string>
</dict>

I have captured this element in an object called settings and I am adding new <key> and <string> elements, and adding some text to those elements. Simple enough so far:

settings.add_element('key').add_text('gutter')
settings.add_element('string').add_text('#282828')

Trouble is, when I write this back out, the XML looks like this (note the last line):

<dict>
  <key>background</key>
  <string>#FFFFFF</string>
  <key>caret</key>
  <string>#000000</string>
  <key>foreground</key>
  <string>#000000</string>
  <key>invisibles</key>
  <string>#BFBFBF</string>
  <key>lineHighlight</key>
  <string>#00000012</string>
  <key>selection</key>
  <string>#BAD6FD</string>
<key>gutter</key><string>#282828</string></dict>

I am using the write (REXML::Document) method to write out the XML (to $stdout at the moment):

tmtheme.write( $stdout )

Also tried

tmtheme.write( $stdout, 2 )

But these don't return the desired results. The following looked promising:

tmtheme.write( $stdout, 2, true )

But this gives me a known error. Update: just tried it on Ruby 1.9 and although I don't get the erro, it doesn't help - I still get the formatting as seen in the example above.

Can anyone tell me how I can format the XML so that it conforms to the formatting style of the rest of the document? It doesn't necessarily need to be done with REXML.

Answer 1

Robert Klemme and Aaron Patterson came up with the goods on the ruby-talk list.

This is the first time a question I've posed on SoF has drawn a complete blank.