@Test
    public void testReturnTypes() {
        assertEquals("test   ", __.__("test   ").lTrim().next());
        assertArrayEquals(new String[]{"hello world ", "test  ", null, "", ""},
                __.inject(" hello world ", "  test  ", null, "", " ").lTrim().toList().toArray());
    }
@author Yang Xia (http://github.com/xiazcy)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/LTrimGlobalStepTest.java