version 0.2.7

fetchAll() fails with [Error: Config value 'user.name' was not found] unless git global config 'user.name' is set to a non-empty string. If the string is empty the error is [Error: Failed to parse signature - Signature cannot have an empty name]. The fetchAll() function does not take a signature parameter, and ends up calling repo.defaultSignature().

To reproduce:
$ git config --global --unset user.name
or
$ git config --global user.name ''

Setting the system or local user.name makes no difference.
As far as I can tell there is no way to set the default user name other than via the command line.