oil AST

(command.CommandList
  children: [
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:test_description)
          op: assign_op.Equal
          rhs: {(SQ <'bisect can handle submodules'>)}
          spids: [4]
        )
      ]
    )
    (C {<.>} {<'./test-lib.sh'>})
    (C {<.>} {(DQ ($ Id.VSub_DollarName '$TEST_DIRECTORY')) <'/lib-submodule-update.sh'>})
    (command.ShFunction
      name: git_bisect
      body: 
        (BraceGroup
          children: [
            (command.AndOr
              ops: [
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
                Id.Op_DAmp
              ]
              children: [
                (command.Simple
                  words: [{<git>} {<status>} {<-su>}]
                  redirects: [(redir op:<Id.Redir_Great '>'> loc:(redir_loc.Fd fd:1) arg:{<expect>})]
                  do_fork: T
                )
                (command.Simple
                  words: [{<ls>} {<-1pR>} {<Id.Lit_Star '*'>}]
                  redirects: [(redir op:<Id.Redir_DGreat '>>'> loc:(redir_loc.Fd fd:1) arg:{<expect>})]
                  do_fork: T
                )
                (C {<tar>} {<cf>} {(DQ ($ Id.VSub_DollarName '$TRASH_DIRECTORY') <'/tmp.tar'>)} 
                  {<Id.Lit_Star '*'>}
                )
                (command.ShAssignment
                  pairs: [
                    (assign_pair
                      lhs: (sh_lhs_expr.Name name:GOOD)
                      op: assign_op.Equal
                      rhs: 
                        {
                          (command_sub
                            left_token: <Id.Left_DollarParen '$('>
                            child: (C {<git>} {<rev-parse>} {<--verify>} {<HEAD>})
                          )
                        }
                      spids: [68]
                    )
                  ]
                )
                (C {<git>} {<checkout>} {(DQ ($ Id.VSub_Number '$1'))})
                (command.Simple
                  words: [{<echo>} {(DQ <foo>)}]
                  redirects: [(redir op:<Id.Redir_Great '>'> loc:(redir_loc.Fd fd:1) arg:{<bar>})]
                  do_fork: T
                )
                (C {<git>} {<add>} {<bar>})
                (C {<git>} {<commit>} {<-m>} {(DQ <'bisect bad'>)})
                (command.ShAssignment
                  pairs: [
                    (assign_pair
                      lhs: (sh_lhs_expr.Name name:BAD)
                      op: assign_op.Equal
                      rhs: 
                        {
                          (command_sub
                            left_token: <Id.Left_DollarParen '$('>
                            child: (C {<git>} {<rev-parse>} {<--verify>} {<HEAD>})
                          )
                        }
                      spids: [127]
                    )
                  ]
                )
                (C {<git>} {<reset>} {<--hard>} {<HEAD> <Id.Lit_Other '^'> <Id.Lit_Other '^'>})
                (C {<git>} {<submodule>} {<update>})
                (C {<git>} {<bisect>} {<start>})
                (C {<git>} {<bisect>} {<good>} {($ Id.VSub_DollarName '$GOOD')})
                (C {<rm>} {<-rf>} {<Id.Lit_Star '*'>})
                (C {<tar>} {<xf>} {(DQ ($ Id.VSub_DollarName '$TRASH_DIRECTORY') <'/tmp.tar'>)})
                (command.Simple
                  words: [{<git>} {<status>} {<-su>}]
                  redirects: [(redir op:<Id.Redir_Great '>'> loc:(redir_loc.Fd fd:1) arg:{<actual>})]
                  do_fork: T
                )
                (command.Simple
                  words: [{<ls>} {<-1pR>} {<Id.Lit_Star '*'>}]
                  redirects: [(redir op:<Id.Redir_DGreat '>>'> loc:(redir_loc.Fd fd:1) arg:{<actual>})]
                  do_fork: T
                )
                (C {<test_cmp>} {<expect>} {<actual>})
                (C {<git>} {<bisect>} {<bad>} {($ Id.VSub_DollarName '$BAD')})
              ]
            )
          ]
        )
    )
    (C {<test_submodule_switch>} {(DQ <git_bisect>)})
    (C {<test_done>})
  ]
)