Every path that continues typed, spelled the way it was — directories with a trailing slash.

Hidden entries only once a dot has been typed, which is the rule every shell uses and the reason .cat does not open with a list of dotfiles. That rule is about what was TYPED, so it is decided once rather than re-asked for every entry in the directory.

One pass. This used to filter twice and then map, walking the entries three times and allocating an array each time; the listing it does first costs five times all of that put together, so the saving is small — but the two-filter shape was also hiding the loop-invariant above.

import { pathsContinuing } from './completion.ts';

pathsContinuing('lib/re', process.cwd()); // ['lib/repl/'] — a directory, and it says so
pathsContinuing('nowhere/at/all', process.cwd()); // [] — an unreadable directory offers nothing