add an unit test for double nest variable lookup

test/integration/variable_test.rb

@@ -157,4 +157,16 @@ class VariableTest < Minitest::Test
       }
     )
   end
+
+  def test_double_nested_variable_lookup
+    assert_template_result(
+      'bar',
+      '{{ list[list[settings.zero]]["foo"] }}',
+      {
+        'list' => [1, { 'foo' => 'bar' }],
+        'settings' => SettingsDrop.new("zero" => 0),
+        'bar' => 'foo',
+      }
+    )
+  end
 end