def test_array_of_arrays
    template = <<template
{{#items}}
start
{{#map}}
  {{a}}
{{/map}}
end
{{/items}}
template

    data = {
      "items" => [
        [ {"a" => 1}, {"a" => 2}, {"a" => 3} ],
        [ {"a" => 4}, {"a" => 5}, {"a" => 6} ],
        [ {"a" => 7}, {"a" => 8}, {"a" => 9} ]
      ]
    }

    assert_equal <<expected, Mustache.render(template, data)
start
1
2
3
end
start
4
5
6
end
start
7
8
9
end
expected
  end