When calling parse('./directory'), the string is supposed to be interpreted as cwd.
https://github.com/jonschlinkert/parse-git-config/blob/master/index.js#L36

Yet that value is passed to resolveConfigPath('./directory') which treats it as the type instead of cwd.
https://github.com/jonschlinkert/parse-git-config/blob/master/index.js#L58
https://github.com/jonschlinkert/parse-git-config/blob/master/index.js#L89
https://github.com/jonschlinkert/parse-git-config/blob/master/index.js#L108

Additionally, this call to configPath passes the type but omits cwd. So when you call resolveConfigPath({cwd, type}) -- or pass the same options object to parse -- it will not do the right thing.
https://github.com/jonschlinkert/parse-git-config/blob/master/index.js#L110