Function recover 

pub(crate) fn recover(channel_dir: &Path) -> Result<()>

Restores a channel folder left half-done by an interrupted run.

A leftover staging folder is deleted. A leftover old folder is deleted when the channel folder exists (the swap finished), or renamed back when it does not (the swap was interrupted between the two renames).

Arguments

• channel_dir - The ch<NN> folder.

Errors

Returns an error if a folder cannot be removed or renamed.