public function testSortByFieldDescending() {
$objects = array(
new TestObject("b"),
new TestObject("a"),
new TestObject("c"),
);
$sort = ClosureExpressionVisitor::sortByField("foo", -1);
usort($objects, $sort);
$this
->assertEquals("c", $objects[0]
->getFoo());
$this
->assertEquals("b", $objects[1]
->getFoo());
$this
->assertEquals("a", $objects[2]
->getFoo());
}