oat: left; }', 0);
  assert_equals(
    sheet.cssRules[0].cssText,
    [
      '@media print {',
      '  #foo { z-index: 23; float: left; }',
      '}'
    ].join('\n')
  );
}, 'one rule');

test(function(t) {
  var sheet = makeSheet(t);
  sheet.insertRule('@media print {}');

  assert_equals(sheet.cssRules.length, 1);
  sheet.cssRules[0].insertRule('#foo { z-index: 23; float: left; }', 0);
  sheet.cssRules[0].insertRule('#bar { float: none; z-index: 45; }', 0);
  assert_equals(
    sheet.cssRules[0].cssTe