..('\n---', '${array[0]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:1)
    bracket_op: (bracket_op.ArrayIndex expr:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
  )
}('\n---', '${array[5+5]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:1)
    bracket_op: 
      (bracket_op.ArrayIndex
        expr: 
          (arith_expr.Binary
            op_id: Id.Arith_Plus
            left: (arith_expr.ArithWord w:{(Id.Lit_Digits 5)})
            right: (arith_expr.ArithWord w:{(Id.Lit_Digits 5)})
          )
      )
  )
}('\n---', '${array[@]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:1)
    bracket_op: (bracket_op.WholeArray op_id:Id.Lit_At)
  )
}('\n---', '${array[*]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:1)
    bracket_op: (bracket_op.WholeArray op_id:Id.Arith_Star)
  )
}('\n---', '${#}')
{(${ Id.VSub_Pound '#')}('\n---', '${!}')
{(${ Id.VSub_Bang '!')}('\n---', '${?}')
{(${ Id.VSub_QMark '?')}('\n---', '${var}')
{(${ Id.VSub_Name var)}('\n---', '${15}')
{(${ Id.VSub_Number 15)}('\n---', '${#var}')
{(braced_var_sub token:(Token id:Id.VSub_Name val:var span_id:2) prefix_op:(Id.VSub_Pound))}('\n---', '${!ref}')
{(braced_var_sub token:(Token id:Id.VSub_Name val:ref span_id:2) prefix_op:(Id.VSub_Bang))}('\n---', '${##}')
{(braced_var_sub token:(Token id:Id.VSub_Pound val:'#' span_id:2) prefix_op:(Id.VSub_Pound))}('\n---', '${array[0]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:1)
    bracket_op: (bracket_op.ArrayIndex expr:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
  )
}('\n---', '${array[@]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:1)
    bracket_op: (bracket_op.WholeArray op_id:Id.Lit_At)
  )
}('\n---', '${#array[0]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:2)
    prefix_op: (Id.VSub_Pound)
    bracket_op: (bracket_op.ArrayIndex expr:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
  )
}('\n---', '${!array[0]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:2)
    prefix_op: (Id.VSub_Bang)
    bracket_op: (bracket_op.ArrayIndex expr:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
  )
}('\n---', '${var#prefix}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_Pound arg_word:{(prefix)})
  )
}('\n---', '${!var#prefix}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:2)
    prefix_op: (Id.VSub_Bang)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_Pound arg_word:{(prefix)})
  )
}('\n---', '${#var#prefix}')
Got expected ParseError: <Expected } after length expression, got %r ('#',) (Token id:Id.VOp1_Pound val:'#' span_id:3) None None>
('\n---', '${##2}')
Got expected ParseError: <Expected } after length expression, got %r ('2',) (Token id:Id.Unknown_Tok val:2 span_id:3) None None>
('\n---', '${undef:-')
Got expected ParseError: <Unexpected token %r (after %s) ('', 'VTest') (Token id:Id.Eof_Real val:'' span_id:3) None None>
('\n---', '${undef:-$')
Got expected ParseError: <Unexpected token %r (after %s) ('', 'VTest') (Token id:Id.Eof_Real val:'' span_id:4) None None>
('\n---', '${undef:-$F')
Got expected ParseError: <Unexpected token %r (after %s) ('', 'VTest') (Token id:Id.Eof_Real val:'' span_id:4) None None>
('\n---', '${x@')
Got expected ParseError: <Unexpected token %r (%s) ('@', 'VOp3') (Token id:Id.VOp3_At val:'@' span_id:2) None None>
('\n---', '${x@Q')
Got expected ParseError: <Expected } after var sub, got %r ('',) (Token id:Id.Eof_Real val:'' span_id:3) None None>
('\n---', '${x%')
Got expected ParseError: <Unexpected token %r (after %s) ('', 'VOp1') (Token id:Id.Eof_Real val:'' span_id:3) None None>
('\n---', '${x/')
Got expected ParseError: <Pattern in ${x/pat/replace} must not be empty () (Token id:Id.Eof_Real val:'' span_id:3) None None>
('\n---', '${x/a/')
Got expected ParseError: <Expected } after replacement string, got %s ('Id.Eof_Real',) (Token id:Id.Eof_Real val:'' span_id:5) None None>.....
('\n---', '${x/a/b')
Got expected ParseError: <Expected } after replacement string, got %s ('Id.Eof_Real',) (Token id:Id.Eof_Real val:'' span_id:6) None None>
('\n---', '${x:')
Got expected ParseError: <Unexpected end of input () None (Token id:Id.Eof_Real val:'' span_id:3) None>
('\n---', '--foo=$func()')
{(--foo) (Id.Lit_Equals '=') 
  (word_part.FuncCall name:(Token id:Id.VSub_DollarName val:'$func' span_id:2) args:(arg_list))
}('\n---', '$func()trailer')
{(word_part.FuncCall name:(Token id:Id.VSub_DollarName val:'$func' span_id:0) args:(arg_list)) 
  (trailer)
}('\n---', '--foo=$func()trailer')
{(--foo) (Id.Lit_Equals '=') 
  (word_part.FuncCall name:(Token id:Id.VSub_DollarName val:'$func' span_id:2) args:(arg_list)) (trailer)
}('\n---', '${#@}')
{(braced_var_sub token:(Token id:Id.VSub_At val:'@' span_id:2) prefix_op:(Id.VSub_Pound))}('\n---', '${#11}')
{(braced_var_sub token:(Token id:Id.VSub_Number val:11 span_id:2) prefix_op:(Id.VSub_Pound))}('\n---', '${#str}')
{(braced_var_sub token:(Token id:Id.VSub_Name val:str span_id:2) prefix_op:(Id.VSub_Pound))}('\n---', '${#array[0]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:2)
    prefix_op: (Id.VSub_Pound)
    bracket_op: (bracket_op.ArrayIndex expr:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
  )
}('\n---', '${#array["key"]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:2)
    prefix_op: (Id.VSub_Pound)
    bracket_op: (bracket_op.ArrayIndex expr:(arith_expr.ArithWord w:{(DQ (key))}))
  )
}--MULTI
('\n---', '@words')
{(word_part.Splice name:(Token id:Id.Lit_Splice val:'@words' span_id:0))}('\n---', '.@words')
{(.) (Id.Lit_Splice '@words')}('\n---', '.@words.')
{(.) (Id.Lit_Splice '@words') (.)}('\n---', '@words[')
Got expected ParseError: <Unexpected token after array splice () (Token id:Id.Lit_LBracket val:'[' span_id:1) None None>
('\n---', '@words.')
Got expected ParseError: <Unexpected token after array splice () (Token id:Id.Lit_Chars val:. span_id:1) None None>
('\n---', '@func()')
{(word_part.FuncCall name:(Token id:Id.Lit_Splice val:'@func' span_id:0) args:(arg_list))}('\n---', '$(echo @func())')
{
  (command_sub
    left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:0)
    command_list: 
      (command.CommandList
        children: [
          (C {(echo)} {(word_part.FuncCall name:(Token id:Id.Lit_Splice val:'@func' span_id:3) args:(arg_list))})
        ]
      )
  )
}('\n---', '$(($(echo @func())))')
{
  (word_part.ArithSub
    anode: 
      (arith_expr.ArithWord
        w: 
          {
            (command_sub
              left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:1)
              command_list: 
                (command.CommandList
                  children: [
                    (C {(echo)} 
                      {(word_part.FuncCall name:(Token id:Id.Lit_Splice val:'@func' span_id:4) args:(arg_list))}
                    )
                  ]
                )
            )
          }
      )
  )
}('\n---', '@func().')
Got expected ParseError: <Unexpected token after array splice () (Token id:Id.Lit_Chars val:. span_id:3) None None>
{(Id.Lit_VarLike 'a=') 
  (sh_array_literal left:(Token id:Id.Op_LParen val:'(' span_id:1) words:[{(1)} {(2)} {(3)}])
}a=(1 2 3)
0
(line_span line_id:0 col:0 length:2)
{(foo)}foo
0
(line_span line_id:0 col:0 length:3)
{(word_part.EscapedLiteral token:(Token id:Id.Lit_EscapedChar val:'\\$' span_id:0))}\$
0
(line_span line_id:0 col:0 length:2)
{(SQ )}''
0
(line_span line_id:0 col:0 length:1)
{(SQ (Token id:Id.Lit_Chars val:sq span_id:1))}'sq'
0
(line_span line_id:0 col:0 length:1)
{(DQ )}""
0
(line_span line_id:0 col:0 length:1)
{(DQ (dq))}"dq"
0
(line_span line_id:0 col:0 length:1)
{
  (command_sub
    left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:0)
    command_list: (command.CommandList children:[(C {(echo)} {(command)} {(sub)})])
  )
}$(echo command sub)
0
(line_span line_id:0 col:0 length:2)
{
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Plus
        left: (arith_expr.ArithWord w:{(Id...Lit_Digits 1)})
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 2)})
      )
  )
}$(( 1 + 2 ))
0
(line_span line_id:0 col:0 length:3)
{(Id.Lit_TildeLike '~user')}~user
0
(line_span line_id:0 col:0 length:5)
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_Pound arg_word:{})
  )
}${var#}
0
(line_span line_id:0 col:0 length:2)
('\n---', '${var/pat/replace}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.PatSub pat:{(pat)} replace:{(replace)} replace_mode:Id.Undefined_Tok)
  )
}('\n---', '${var//pat/replace}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.PatSub pat:{(pat)} replace:{(replace)} replace_mode:Id.Lit_Slash)
  )
}('\n---', '${var/%pat/replace}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.PatSub pat:{(pat)} replace:{(replace)} replace_mode:Id.Lit_Percent)
  )
}('\n---', '${var/#pat/replace}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.PatSub pat:{(pat)} replace:{(replace)} replace_mode:Id.Lit_Pound)
  )
}('\n---', '${var/pat}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.PatSub pat:{(pat)} replace_mode:Id.Undefined_Tok)
  )
}('\n---', '${var//pat}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.PatSub pat:{(pat)} replace_mode:Id.Lit_Slash)
  )
}('\n---', '${var/pat//}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: 
      (suffix_op.PatSub pat:{(pat)} replace:{(Id.Lit_Slash /)} replace_mode:Id.Undefined_Tok)
  )
}('\n---', '${var/pat///}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: 
      (suffix_op.PatSub
        pat: {(pat)}
        replace: {(Id.Lit_Slash /) (Id.Lit_Slash /)}
        replace_mode: Id.Undefined_Tok
      )
  )
}('\n---', '${var/pat/"//"}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.PatSub pat:{(pat)} replace:{(DQ (//))} replace_mode:Id.Undefined_Tok)
  )
}('\n---', '${var////\\\\/}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: 
      (suffix_op.PatSub
        pat: {(Id.Lit_Slash /)}
        replace: 
          {(word_part.EscapedLiteral token:(Token id:Id.Lit_EscapedChar val:'\\\\' span_id:6)) 
            (Id.Lit_Slash /)
          }
        replace_mode: Id.Lit_Slash
      )
  )
}---
ls "foo"
()
{(ls)}{(DQ (foo))}(Token id:Id.Eof_Real val:'' span_id:5)---
$(( 1 + 2 ))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Plus
        left: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 2)})
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:10)---
$(echo $(( 1 )) )
()
{
  (command_sub
    left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:0)
    command_list: 
      (command.CommandList
        children: [(C {(echo)} {(word_part.ArithSub anode:(arith_expr.ArithWord w:{(Id.Lit_Digits 1)}))})]
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:11)---
echo ${#array[@]} b
()
{(echo)}{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:4)
    prefix_op: (Id.VSub_Pound)
    bracket_op: (bracket_op.WholeArray op_id:Id.Lit_At)
  )
}{(b)}(Token id:Id.Eof_Real val:'' span_id:11)---
echo $(( ${#array[@]} ))
()
{(echo)}{
  (word_part.ArithSub
    anode: 
      (arith_expr.ArithWord
        w: 
          {
            (braced_var_sub
              token: (Token id:Id.VSub_Name val:array span_id:6)
              prefix_op: (Id.VSub_Pound)
              bracket_op: (bracket_op.WholeArray op_id:Id.Lit_At)
            )
          }
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:14)---
echo ${@%suffix}
()
{(echo)}{
  (braced_var_sub
    token: (Token id:Id.VSub_At val:'@' span_id:3)
    suffix_op: (suffix_op.Unary op_.id:Id.VOp1_Percent arg_word:{(suffix)})
  )
}(Token id:Id.Eof_Real val:'' span_id:7)---
${@}
()
{(${ Id.VSub_At '@')}(Token id:Id.Eof_Real val:'' span_id:3)---
echo ${var,,}
()
{(echo)}{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:3)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_DComma arg_word:{})
  )
}(Token id:Id.Eof_Real val:'' span_id:6)---
echo ${var,,?}
()
{(echo)}{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:3)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_DComma arg_word:{('?')})
  )
}(Token id:Id.Eof_Real val:'' span_id:7)---
${\
foo}
()
{(${ Id.VSub_Name foo)}(Token id:Id.Eof_Real val:'' span_id:4)---
${foo\
}
()
{(${ Id.VSub_Name foo)}(Token id:Id.Eof_Real val:'' span_id:4)---
${foo#\
yo}
()
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:foo span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_Pound arg_word:{(yo)})
  )
}(Token id:Id.Eof_Real val:'' span_id:6)---
"${foo#\
yo}"
()
{
  (DQ 
    (braced_var_sub
      token: (Token id:Id.VSub_Name val:foo span_id:2)
      suffix_op: (suffix_op.Unary op_id:Id.VOp1_Pound arg_word:{(yo)})
    )
  )
}(Token id:Id.Eof_Real val:'' span_id:8)---
1 + 2
()
{(Id.Lit_Digits 1)}(Token id:Id.Arith_Plus val:'+' span_id:2){(Id.Lit_Digits 2)}(Token id:Id.Eof_Real val:'' span_id:5)---
a + b
()
{(Id.Lit_ArithVarLike a)}(Token id:Id.Arith_Plus val:'+' span_id:2){(Id.Lit_ArithVarLike b)}(Token id:Id.Eof_Real val:'' span_id:5)---
$a * $b
()
{($ Id.VSub_DollarName '$a')}(Token id:Id.Arith_Star val:'*' span_id:2){($ Id.VSub_DollarName '$b')}(Token id:Id.Eof_Real val:'' span_id:5)---
${a} * ${b}
()
{(${ Id.VSub_Name a)}(Token id:Id.Arith_Star val:'*' span_id:4){(${ Id.VSub_Name b)}(Token id:Id.Eof_Real val:'' span_id:9)---
$(echo 1) * $(echo 2)
()
{
  (command_sub
    left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:0)
    command_list: (command.CommandList children:[(C {(echo)} {(1)})])
  )
}(Token id:Id.Arith_Star val:'*' span_id:6){
  (command_sub
    left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:8)
    command_list: (command.CommandList children:[(C {(echo)} {(2)})])
  )
}(Token id:Id.Eof_Real val:'' span_id:13)---
`echo 1` + 2
()
{
  (command_sub
    left_token: (Token id:Id.Left_Backtick val:'`' span_id:0)
    command_list: (command.CommandList children:[(C {(echo)} {(1)})])
  )
}(Token id:Id.Arith_Plus val:'+' span_id:8){(Id.Lit_Digits 2)}(Token id:Id.Eof_Real val:'' span_id:11)---
$((1 + 2)) * $((3 + 4))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Plus
        left: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 2)})
      )
  )
}(Token id:Id.Arith_Star val:'*' span_id:9){
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Plus
        left: (arith_expr.ArithWord w:{(Id.Lit_Digits 3)})
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 4)})
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:19)---
'single quoted'
()
{(SQ (Token id:Id.Lit_Chars val:'single quoted' span_id:1))}(Token id:Id.Eof_Real val:'' span_id:3)---
"${a}" + "${b}"
()
{(DQ (${ Id.VSub_Name a))}(Token id:Id.Arith_Plus val:'+' span_id:6){(DQ (${ Id.VSub_Name b))}(Token id:Id.Eof_Real val:'' span_id:13)---
$# + $$
()
{($ Id.VSub_Pound '$#')}(Token id:Id.Arith_Plus val:'+' span_id:2){($ Id.VSub_Dollar '$$')}(Token id:Id.Eof_Real val:'' span_id:5)---
$(( x[0] < 5 ))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Less
        left: 
          (arith_expr.Binary
            op_id: Id.Arith_LBracket
            left: (arith_expr.VarRef token:(Token id:Id.Lit_ArithVarLike val:x span_id:2))
            right: (arith_expr.ArithWord w:{(Id.Lit_Digits 0)})
          )
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 5)})
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:13)---
$(( ++i ))
()
{
  (word_part.ArithSub
    anode: (arith_expr.UnaryAssign op_id:Id.Arith_DPlus child:(sh_lhs_expr.Name name:i))
  )
}(Token id:Id.Eof_Real val:'' span_id:7)---
$(( i++ ))
()
{........
  (word_part.ArithSub
    anode: (arith_expr.UnaryAssign op_id:Id.Node_PostDPlus child:(sh_lhs_expr.Name name:i))
  )
}(Token id:Id.Eof_Real val:'' span_id:7)---
$(( x -= 1))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.BinaryAssign
        op_id: Id.Arith_MinusEqual
        left: (sh_lhs_expr.Name name:x)
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:9)---
$(( x |= 1))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.BinaryAssign
        op_id: Id.Arith_PipeEqual
        left: (sh_lhs_expr.Name name:x)
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:9)---
$(( x[0] = 1 ))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.BinaryAssign
        op_id: Id.Arith_Equal
        left: (sh_lhs_expr.IndexedName name:x index:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:13)---
$(( 1 | 0 ))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Pipe
        left: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 0)})
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:10)---
$((0x$size))
()
{
  (word_part.ArithSub
    anode: 
      (arith_expr.ArithWord
        w: {(Id.Lit_Digits 0) (Id.Lit_ArithVarLike x) ($ Id.VSub_DollarName '$size')}
      )
  )
}(Token id:Id.Eof_Real val:'' span_id:6)('\n---', '$(( (1+2) ))')
{
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Plus
        left: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 2)})
      )
  )
}('\n---', '$(( (1+2) ))')
{
  (word_part.ArithSub
    anode: 
      (arith_expr.Binary
        op_id: Id.Arith_Plus
        left: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
        right: (arith_expr.ArithWord w:{(Id.Lit_Digits 2)})
      )
  )
}('\n---', '${foo:0}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:foo span_id:1)
    suffix_op: (suffix_op.Slice begin:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
  )
}('\n---', '${foo:0:1}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:foo span_id:1)
    suffix_op: 
      (suffix_op.Slice
        begin: (arith_expr.ArithWord w:{(Id.Lit_Digits 0)})
        length: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
      )
  )
}('\n---', '${foo:1+2:2+3}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:foo span_id:1)
    suffix_op: 
      (suffix_op.Slice
        begin: 
          (arith_expr.Binary
            op_id: Id.Arith_Plus
            left: (arith_expr.ArithWord w:{(Id.Lit_Digits 1)})
            right: (arith_expr.ArithWord w:{(Id.Lit_Digits 2)})
          )
        length: 
          (arith_expr.Binary
            op_id: Id.Arith_Plus
            left: (arith_expr.ArithWord w:{(Id.Lit_Digits 2)})
            right: (arith_expr.ArithWord w:{(Id.Lit_Digits 3)})
          )
      )
  )
}('\n---', '${foo::1}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:foo span_id:1)
    suffix_op: (suffix_op.Slice length:(arith_expr.ArithWord w:{(Id.Lit_Digits 1)}))
  )
}('\n---', '${var:-default]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VTest_ColonHyphen arg_word:{('default]')})
  )
}('\n---', '~/git/oilshell/oil')
{(Id.Lit_TildeLike '~') (/git/oilshell/oil)}('\n---', '~andy/git/oilshell/oil')
{(Id.Lit_TildeLike '~andy') (/git/oilshell/oil)}('\n---', '~andy_c/git/oilshell/oil')
{(Id.Lit_TildeLike '~andy_c') (/git/oilshell/oil)}('\n---', '~andy.c/git/oilshell/oil')
{(Id.Lit_TildeLike '~andy.c') (/git/oilshell/oil)}('\n---', '~andy-c/git/oilshell/oil')
{(Id.Lit_TildeLike '~andy-c') (/git/oilshell/oil)}('\n---', '~andy-c:git/oilshell/oil')
{(Id.Lit_TildeLike '~andy-c') (Id.Lit_Other ':') (git/oilshell/oil)}('\n---', '${var#}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: ..
----------------------------------------------------------------------
Ran 20 tests in 0.074s

OK
(suffix_op.Unary op_id:Id.VOp1_Pound arg_word:{})
  )
}('\n---', '${var#prefix}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_Pound arg_word:{(prefix)})
  )
}('\n---', '${var##}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_DPound arg_word:{})
  )
}('\n---', '${var##prefix}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_DPound arg_word:{(prefix)})
  )
}('\n---', '${var%suffix}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_Percent arg_word:{(suffix)})
  )
}('\n---', '${var%%suffix}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:var span_id:1)
    suffix_op: (suffix_op.Unary op_id:Id.VOp1_DPercent arg_word:{(suffix)})
  )
}('\n---', '${name}')
{(${ Id.VSub_Name name)}('\n---', '${name[0]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:name span_id:1)
    bracket_op: (bracket_op.ArrayIndex expr:(arith_expr.ArithWord w:{(Id.Lit_Digits 0)}))
  )
}('\n---', '${array[@]}')
{
  (braced_var_sub
    token: (Token id:Id.VSub_Name val:array span_id:1)
    bracket_op: (bracket_op.WholeArray op_id:Id.Lit_At)
  )
}