Here's a test and fix for #1269. I originally thought the fix was going to be in magic.py, and went ahead and fixed the typos in that file, but it turned out that the fix ended up going into _process_common.py - hope that's ok.
Nice! Looks sensible to me. I imagine we are likely to run into this sort of thing a few more times before we rewrite the magic arg-splitting in a cleaner way.
The process_common thing is a bit funky - we really should not be using the same code to split magic arguments and split strings into a Popen command-list, but we do, so your fix is probably in the right place. That's more for the major reorganization of magics that @fperez has in mind.
needs a quick rebase, due to some unfortunate cleanup that had to be done in master.
fix some typos in magic
test for GH #1269
shlex shouldn't parse out comments, closes #1269