(command.CommandList
  children: [
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:test_description)
          op: assign_op.Equal
          rhs: {(DQ <'Tests history walking performance'>)}
          spids: [4]
        )
      ]
    )
    (C {<.>} {<'./perf-lib.sh'>})
    (C {<test_perf_default_repo>})
    (C {<test_perf>} {(SQ <'rev-list --all'>)} {(SQ <'\n'> <'\tgit rev-list --all >/dev/null\n'>)})
    (C {<test_perf>} {(SQ <'rev-list --all --objects'>)} 
      {(SQ <'\n'> <'\tgit rev-list --all --objects >/dev/null\n'>)}
    )
    (C {<test_expect_success>} {(SQ <'create new unreferenced commit'>)} 
      {(SQ <'\n'> <'\tcommit=$(git commit-tree HEAD^{tree} -p HEAD)\n'>)}
    )
    (C {<test_perf>} {(SQ <'rev-list $commit --not --all'>)} 
      {(SQ <'\n'> <'\tgit rev-list $commit --not --all >/dev/null\n'>)}
    )
    (C {<test_perf>} {(SQ <'rev-list --objects $commit --not --all'>)} 
      {(SQ <'\n'> <'\tgit rev-list --objects $commit --not --all >/dev/null\n'>)}
    )
    (C {<test_done>})
  ]
)