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Ran 1 test in 0.027s

OK
('\n---', 'foo')
{<foo>}('\n---', "'hi'")
{(SQ <hi>)}('\n---', '$var')
{($ Id.VSub_DollarName var)}('\n---', '${var}')
{(${ Id.VSub_Name var)}('\n---', ' "$var" ')
{(DQ ($ Id.VSub_DollarName var))}('\n---', ' "${var}" ')
{(DQ (${ Id.VSub_Name var))}('\n---', ' $((1+2)) ')
{
  (word_part.ArithSub
    left: <Id.Left_DollarDParen '$(('>
    anode: (arith_expr.Binary op_id:Id.Arith_Plus left:{<Id.Lit_Digits 1>} right:{<Id.Lit_Digits 2>})
    right: <Id.Right_DollarDParen _>
  )
}('\n---', ' $(echo hi) ')
{
  (CommandSub
    left_token: <Id.Left_DollarParen '$('>
    child: 
      (command.Simple
        blame_tok: <echo>
        more_env: []
        words: [{<echo>} {<hi>}]
        redirects: []
        do_fork: T
      )
    right: <Id.Eof_RParen _>
  )
}('\n---', ' "$((1+2))" ')
{
  (DQ 
    (word_part.ArithSub
      left: <Id.Left_DollarDParen '$(('>
      anode: (arith_expr.Binary op_id:Id.Arith_Plus left:{<Id.Lit_Digits 1>} right:{<Id.Lit_Digits 2>})
      right: <Id.Right_DollarDParen _>
    )
  )
}('\n---', ' "$(echo hi)" ')
{
  (DQ 
    (CommandSub
      left_token: <Id.Left_DollarParen '$('>
      child: 
        (command.Simple
          blame_tok: <echo>
          more_env: []
          words: [{<echo>} {<hi>}]
          redirects: []
          do_fork: T
        )
      right: <Id.Eof_RParen _>
    )
  )
}('\n---', ' $src/file ')
{($ Id.VSub_DollarName src) <'/file'>}('\n---', ' ${src}/file ')
{(${ Id.VSub_Name src) <'/file'>}('\n---', ' "$src/file" ')
{(DQ ($ Id.VSub_DollarName src) <'/file'>)}('\n---', ' "${src}/file" ')
{(DQ (${ Id.VSub_Name src) <'/file'>)}('\n---', ' $((1+2))$(echo hi) ')
{
  (word_part.ArithSub
    left: <Id.Left_DollarDParen '$(('>
    anode: (arith_expr.Binary op_id:Id.Arith_Plus left:{<Id.Lit_Digits 1>} right:{<Id.Lit_Digits 2>})
    right: <Id.Right_DollarDParen _>
  ) 
  (CommandSub
    left_token: <Id.Left_DollarParen '$('>
    child: 
      (command.Simple
        blame_tok: <echo>
        more_env: []
        words: [{<echo>} {<hi>}]
        redirects: []
        do_fork: T
      )
    right: <Id.Eof_RParen _>
  )
}('\n---', ' ~/src ')
{<Id.Lit_TildeLike '~'> <'/src'>}('\n---', ' ~bob/foo ')
{<Id.Lit_TildeLike '~bob'> <'/foo'>}('\n---', 'notleading~')
{<notleading> <Id.Lit_TildeLike '~'>}('\n---', ' "~/src" ')
{(DQ <'~/src'>)}('\n---', ' "~bob/foo" ')
{(DQ <'~bob/foo'>)}