A few questions about channels

[ison <ison@airmail.cc>]

Several questions about channels have been on my mind which I haven't been able to find any documentation on. So I figured I would ask them all in one place since they seem like fairly standard questions that could help others setting up channels in the future as well.

1) Is it possible to make a channel from a local git repository? (That is to say, a directory on the local machine initialized as a git repository)

2) Is it possible to use private remote repositories as channels? The issue here seems to be one of authentication. I'm wonder if there is (or should be) an "authentication" field one would add to the channel definition in the channels.scm file.

3) How can a channel provide patch files which can be used with "search-patches"? I attempted to look through the guix code in gnu/packages.scm and from what I can tell it looks like search-patches only looks in paths included from "%load-path". There is also a comment saying that it picks up the paths from $GUIX_PACKAGE_PATH, but I thought that variable was being deprecated in favor of channels. If so, shouldn't search-patches also look inside the channels repository for patch files?