Add recursive and lenient modes to stub generation

[rtpg]

This is something I personally use for stub generation: whenever stubgen'ing a packages, you'll often want to generate modules inside of it.

If you pass in --recursive, then you'll generate stubs for provided modules and its included modules if its a package.

Also included is --lenient. This will ignore exceptions (just printing a warning) when some module gens fail. This will let you stubgen for larger modules, even if they include some issues. I was having trouble using --recursive without this.

[gvanrossum]

Thanks, these are good ideas. Can you fix the test?

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--Guido (mobile)

[gvanrossum]

I'm really not happy that this imports the target package name. At the very least you should honor the --no-import flag.

[rtpg]

Oh, good point! I don't believe importing is strictly necessary here, since at this point I'm simply trying to walk the packages. I'll look into re-implementing this function without __import__

[gvanrossum]

I think this should have a different name, maybe --ignore-errors.

[rtpg]

I renamed the lenient mode to --ignore-errors.

After looking at pkgutil.walk_packages was implemented, I saw that it itself is using __import__, so I decided to simply trigger an error when --no-import and --recursive are used together. It's surely possible to do this without __import__ but I'll leave that to someone who understands loading semantics.

[gvanrossum]

OK. Typically we just use o's.walk(), see e.g. main.py or build.py (I forget which).

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--Guido (mobile)

[gvanrossum]

Thanks! If you want to work more on this just open a new PR. I'm looking to seeing more contributions from you.