I'm not sure, but I'm not deeply familiar with this part of the code. In general, I think it's good to be able to induce all of the failure cases for all of the error handling code that's being added.

This can be time-consuming work, but I would argue that this is the file system -- anything less is an unacceptable risk. This quote from my boss comes to mind:

Remember: you are (or should be!) always empowered as an engineer to take more time to test your work. -- http://dtrace.org/blogs/bmc/2015/09/03/software-immaculate-f...