Behavior of "allow_missing=True" with "multiple=True"

[dgilland]

Currently, when you define an Arg such as:

myargs = {'somearg': Arg(allow_missing=True, multiple=True)}

When somearg is not supplied, the parsed myargs is {'somearg': []}.

However, when you define an Arg with multiple=False:

myargs = {'somearg': Arg(allow_missing=True)}

When somearg is not supplied, the parsed myargs is {}.

I was surprised by this behavior as I assumed that when allow_missing=True and the argument is not supplied, that no parsed value would be returned for both the multiple=False and multiple=True cases.

Is this intentional? Or should no parsed value be returned in the case of Arg(allow_missing=True, multiple=True) instead of []?

[sloria]

@dgilland You are correct; the current behavior is incorrect. In your example, 'somearg' should not be in the parsed arguments if it is not passed.

I will issue a fix soon. Thanks for reporting!

[dgilland]

Awesome! Thanks for fixing the issue so quickly! 👍

Kudos on the library as well! Very helpful/useful.