Highlight blacklisted paths

[danielshahaf]

Supposing ZSH_HIGHLIGHT_DIRS_BLACKLIST=( /foo ), how should : /foo/bar be highlighted?

Currently, it's highlighted as any ordinary (unquoted non-option) word is, even though it may denote a filename.

Consider adding a style for such words, so users would be able to distinguish "is definitely a file", "is definitely not a file", and "indeterminate". (In the last sentence I glossed over the path/path_prefix distinction for simplicity.)

In terms of the above example, should the new style be set for /foo ( "3 6 blacklisted-parent-path") or for /foo/bar ("3 10 path-under-blacklisted-parent")?