(command.CommandList
  children: [
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:test_description)
          op: assign_op.Equal
          rhs: {(SQ <'Test revision walking api'>)}
          spids: [13]
        )
      ]
    )
    (C {<.>} {<'./test-lib.sh'>})
    (command.Simple
      words: [{<cat>}]
      redirects: [
        (redir op:<Id.Redir_Great '>'> loc:(redir_loc.Fd fd:1) arg:{<run_twice_expected>})
        (redir
          op: <Id.Redir_DLessDash '<<-'>
          loc: (redir_loc.Fd fd:0)
          arg: 
            (redir_param.HereDoc
              here_begin: {<EOF>}
              here_end_span_id: 39
              stdin_parts: [
                <'1st\n'>
                <' > add b\n'>
                <' > add a\n'>
                <'2nd\n'>
                <' > add b\n'>
                <' > add a\n'>
              ]
            )
        )
      ]
      do_fork: T
    )
    (C {<test_expect_success>} {(SQ <setup>)} 
      {
        (SQ <'\n'> <'\techo a > a &&\n'> <'\tgit add a &&\n'> <'\tgit commit -m "add a" &&\n'> 
          <'\techo b > b &&\n'> <'\tgit add b &&\n'> <'\tgit commit -m "add b"\n'>
        )
      }
    )
    (C {<test_expect_success>} {(SQ <'revision walking can be done twice'>)} 
      {
        (SQ <'\n'> <'\ttest-revision-walking run-twice >run_twice_actual &&\n'> 
          <'\ttest_cmp run_twice_expected run_twice_actual\n'>
        )
      }
    )
    (C {<test_done>})
  ]
)