-- want --
valid:
$work/valid.cue
$work/vendor/x/y

omitted:
$work/.hg_archival.txt: file is inserted by 'hg archive' and is always omitted
$work/sub/cue.mod/module.cue: file is in another module
$work/.git: directory is a version control repository

invalid:
$work/CUE.MOD: cue.mod directories must have lowercase names
$work/invalid.cue': malformed file path "invalid.cue'": invalid char '\''
-- valid.cue --
-- CUE.MOD --
-- invalid.cue' --
-- vendor/x/y --
-- sub/cue.mod/module.cue --
-- .hg_archival.txt --
-- .git/x --