(CommandList
  children: [
    (C {(set)} {(-eu)})
    (Assignment
      keyword: Assign_None
      pairs: [
        (assign_pair
          lhs: (LhsName name:RUNFILES)
          op: Equal
          rhs: 
            {
              (BracedVarSub
                token: <VSub_Name RUNFILES>
                suffix_op: 
                  (StringUnary
                    op_id: VTest_ColonHyphen
                    arg_word: {($ VSub_Number "$0") (.runfiles) (Lit_Slash /) (io_bazel)}
                  )
                spids: [56 63]
              )
            }
          spids: [55]
        )
      ]
      spids: [55]
    )
    (C {(source)} {(DQ (${ VSub_Name RUNFILES) (/examples/shell/lib.sh))})
    (C {(showfile)})
  ]
)