text: // Disallow $ in field names - SERVER-3730
  
  t = db.jstest_updateh
  t.drop()
  
  t.insert( {x:1} )
  
  t.update( {x:1}, {$set: {y:1}} ) // ok
  e = db.getLastErrorObj()
  assert.eq( e.err, null )
  
  t.update( {x:1}, {$set: {$z:1}} ) // not ok
  e = db.getLastErrorObj()
  assert( e.err != null )
  
  // TODO: This shouldn't be supported, and it isn't with the new update framework, but we
  // currently don't have a good way to check which mode we are in. When we do have that, add
  // this test guarded under that condition. Or, when we remove the old update path just enable
  // this test.
  //
  // t.update( {x:1}, {$set: {'a.$b':1}} ) // not ok
  // e = db.getLastErrorObj()
  // assert( e.err != null )
  
  t.update( {x:1}, {$unset: {$z:1}} ) // unset ok to remove bad fields
  e = db.getLastErrorObj()
  assert.eq( e.err, null )
  
  t.update( {x:1}, {$inc: {$z:1}} ) // not ok
  e = db.getLastErrorObj()
  assert( e.err != null )
  
  t.update( {x:1}, {$pushAll: {$z:[1,2,3]}} ) // not ok
  e = db.getLastErrorObj()
  assert( e.err != null )
  
  t.update( {x:1}, {$pushAll: {z:[1,2,3]}} ) // ok
  e = db.getLastErrorObj()
  assert.eq( e.err, null )
  