tensorflow: Saver can't handle filename only

Hey everyone,

it seems to me like - at least on Windows - the tf saver can’t save model files whose path consists only of the file’s name with no parent path, relative nor absolute. The issue lies at or around saver.py:1363 where it tries to check whether the parent directory of the file is actually a directory. There is no parent directory given (i.e. an empty string) and as such gFile.IsDirectory can’t check anything. It fails and raises a ValueError that the parent directory does not exist.

Expected behavior in my opinion would be that the current working directory is used as the parent path when using no path/just a filename (i.e. a relative path).

Some details about my system specs:

• Windows 10
• Python 3.5.2
• TF 0.12.0 (in a virtual environment; pip install tensorflow --upgrade just executed; issue persists)

So, I’m wondering whether this is an expected behavior and how to deal with it or if it is an actual bug that needs to be addressed.