Csv(None) hangs

[iurisilvio]

The shlex splitter hangs with None as input, so config("FOO", default=None, cast=Csv()) hangs the application.

I expected it to return an empty list. I think Csv()(None) should return [] because if it was a required config, it would fail before.

from decouple import Csv
Csv()(None)  # it hangs

To understand what was hanging, I tried it:

from shlex import shlex
splitter = shlex(None, posix=True)
list(splitter)  # it hangs

Based on docs:

Since the split() function instantiates a shlex instance, passing None for s will read the string to split from standard input.)