Error raising with empty stashes
As also reported in this SO comment, the command git rev-list --walk-reflogs --count refs/stash raises an error when there are no stashes present.
This results in push-all and import to fail in certain situations. You could call the push-all command invocation when the stash is actually empty an user-error, however doing an import when the stash is empty, is probably a quite common task.
Anyways, kudos for this great tool, I will definitly use it anyway, because even though errors are raised, the functionality is still given in both cases.
Thanks for the bug report; should be an easy fix, I'll look into it when I get the chance.
You can actually have a look at the open PR and merge it. It fixes not only this error, but also an error regarding the drop functionality.