Function nextToken

source code/utils/bash/bashParser.ts:304–593

* Scan next token. Context-sensitive: `cmd` mode treats [ as operator (test * command start), `arg` mode treats [ as word char (glob/subscript).

(L: Lexer, ctx: 'cmd' | 'arg' = 'arg')

 * command start), `arg` mode treats [ as word char (glob/subscript).
 */
function nextToken(L: Lexer, ctx: 'cmd' | 'arg' = 'arg'): Token {
  skipBlanks(L)
  const start = L.b
  if (L.i >= L.len) return { type: 'EOF', value: '', start, end: start }

  const c = L.src[L.i]!
  const c1 = peek(L, 1)
  const c2 = peek(L, 2)

  if (c === '\n') {
    advance(L)
    return { type: 'NEWLINE', value: '\n', start, end: L.b }
  }

  if (c === '#') {
    const si = L.i
    while (L.i < L.len && L.src[L.i] !== '\n') advance(L)
    return {
      type: 'COMMENT',
      value: L.src.slice(si, L.i),
      start,
      end: L.b,
    }
  }

  // Multi-char operators (longest match first)
  if (c === '&' && c1 === '&') {
    advance(L)
    advance(L)
    return { type: 'OP', value: '&&', start, end: L.b }
  }
  if (c === '|' && c1 === '|') {
    advance(L)
    advance(L)
    return { type: 'OP', value: '||', start, end: L.b }
  }
  if (c === '|' && c1 === '&') {
    advance(L)
    advance(L)
    return { type: 'OP', value: '|&', start, end: L.b }
  }
  if (c === ';' && c1 === ';' && c2 === '&') {
    advance(L)
    advance(L)
    advance(L)
    return { type: 'OP', value: ';;&', start, end: L.b }
  }
  if (c === ';' && c1 === ';') {
    advance(L)
    advance(L)
    return { type: 'OP', value: ';;', start, end: L.b }
  }
  if (c === ';' && c1 === '&') {
    advance(L)
    advance(L)
    return { type: 'OP', value: ';&', start, end: L.b }
  }
  if (c === '>' && c1 === '>') {