Function fold 

pub fn fold(text: &str, width: usize) -> String

The width and the fill, which live in headwater_check::fill and are named here so that a caller of this module keeps writing paint::WIDTH.

They moved down when the check report gained a layout: the report and the help are laid out by one implementation, and headwater-check is the crate every report composer can reach. Nothing is re-implemented here. The text, folded to width columns, breaking only where there is a space.