Function isStaticRedirectTarget

src/utils/bash/commands.ts:47–81

* Checks if a redirection target is a simple static file path that can be safely stripped. * Returns false for targets containing dynamic content (variables, command substitutions, globs, * shell expansions) which should remain visible in permission prompts for security.

(target: string)

 * shell expansions) which should remain visible in permission prompts for security.
 */
function isStaticRedirectTarget(target: string): boolean {
  // SECURITY: A static redirect target in bash is a SINGLE shell word. After
  // the adjacent-string collapse at splitCommandWithOperators, multiple args
  // following a redirect get merged into one string with spaces. For
  // `cat > out /etc/passwd`, bash writes to `out` and reads `/etc/passwd`,
  // but the collapse gives us `out /etc/passwd` as the "target". Accepting
  // this merged blob returns `['cat']` and pathValidation never sees the path.
  // Reject any target containing whitespace or quote chars (quotes indicate
  // the placeholder-restoration preserved a quoted arg).
  if (/[\s'"]/.test(target)) return false
  // Reject empty string — path.resolve(cwd, '') returns cwd (always allowed).
  if (target.length === 0) return false
  // SECURITY (parser differential hardening): shell-quote parses `#foo` at
  // word-initial position as a comment token. In bash, `#` after whitespace
  // also starts a comment (`> #file` is a syntax error). But shell-quote
  // returns it as a comment OBJECT; splitCommandWithOperators maps it back to
  // string `#foo`. This differs from extractOutputRedirections (which sees the
  // comment object as non-string, missing the target). While `> #file` is
  // unexecutable in bash, rejecting `#`-prefixed targets closes the differential.
  if (target.startsWith('#')) return false
  return (
    !target.startsWith('!') && // No history expansion like !!, !-1, !foo
    !target.startsWith('=') && // No Zsh equals expansion (=cmd expands to /path/to/cmd)
    !target.includes('$') && // No variables like $HOME
    !target.includes('`') && // No command substitution like `pwd`
    !target.includes('*') && // No glob patterns
    !target.includes('?') && // No single-char glob
    !target.includes('[') && // No character class glob
    !target.includes('{') && // No brace expansion like {1,2}
    !target.includes('~') && // No tilde expansion
    !target.includes('(') && // No process substitution like >(cmd)
    !target.includes('<') && // No process substitution like <(cmd)
    !target.startsWith('&') // Not a file descriptor like &1
  )
}

export type { CommandPrefixResult, CommandSubcommandPrefixResult }