add support for env -S = env --split-string, to parse multiple arguments

[milahu]

actual

> shebangCommand('#!/usr/bin/env -S node -v');
'-S'

expected

> shebangCommand('#!/usr/bin/env -S node -v');
['node', '-v']

man env

       -S, --split-string=S
              process and split S into separate arguments; used to pass multiple arguments on shebang lines

currently, these shebang parsers fail

• https://www.npmjs.com/package/shebang-command
• https://www.npmjs.com/package/shebang
• https://www.npmjs.com/package/shebang-file

related issues

• exec: -S: invalid option. pnpm fails to parse shebang: #!/usr/bin/env -S node pnpm/pnpm#5575
  • fix shebangExpr: ignore -S argument for /usr/bin/env pnpm/cmd-shim#42

quickfix

function parseShebang(fileText) {
  // based on https://github.com/pnpm/cmd-shim
  // see also https://github.com/npm/cmd-shim
  // examples:
  // "#!/bin/sh" -> ["/bin/sh", ""]
  // "#! /usr/bin/bash a b c" -> ["/usr/bin/bash", " a b c"]
  // "#! /usr/bin/env -S bash a b c" -> ["bash", " a b c"]
  // "#! /usr/bin/env -Sbash a b c" -> ["bash", " a b c"]
  const shebangExpr = /^#!\s*(?:\/usr\/bin\/env\s+(?:-S)?)?\s*(\S+)(.*)$/;
  let firstLineEnd = fileText.indexOf('\n');
  if (firstLineEnd == -1) firstLineEnd = fileText.length;
  const firstLine = fileText.slice(0, firstLineEnd).trimRight();
  const shebang = firstLine.match(shebangExpr);
  if (!shebang) return null;
  const [_, arg0, args] = shebang;
  return [arg0, args];
}