tests/notcapable

largefiles: restore normal 'clone -u' and 'clone -U' functionality

Previously, tip would be checked out regardless of the -u or -U parameter.  I'm
not sure what the 'required for successful walkchangerevs' comment meant, but it
appears to reference code which has since moved to downloadlfiles() in
7d6a660ca151.  Perhaps it was to force caching when the -U parameter is given?
The price of this change is that -U --all-largefiles won't cache anything.  That
will be fixed next.

Note that X + Y in the 'X largefiles updated, n removed' and 'Y additional
largefiles cached' lines do not add up to the same values in these tests, but
all of the largefiles have been downloaded.  The reason being that several
largefiles have the same content (eb7338044 is pointed to by sub/large2, large3
and sub/large4).  In the 'clone -u 1' operation, this largefile is cached to
populate the working directory, even without --all-largefiles.  That means the
file isn't downloaded again and cached in the rev where large3 and sub/large4
both point to this file.  Downloading that one file in that one rev seems to be
counted twice with 'clone -u 0'.  (Maybe it is also being downloaded twice?)

# Disable the $CAP wire protocol capability.

if test -z "$CAP"
then
    echo "CAP environment variable not set."
fi

cat > notcapable-$CAP.py << EOF
from mercurial import extensions, peer, localrepo
def extsetup():
    extensions.wrapfunction(peer.peerrepository, 'capable', wrapcapable)
    extensions.wrapfunction(localrepo.localrepository, 'peer', wrappeer)
def wrapcapable(orig, self, name, *args, **kwargs):
    if name in '$CAP'.split(' '):
        return False
    return orig(self, name, *args, **kwargs)
def wrappeer(orig, self):
    # Since we're disabling some newer features, we need to make sure local
    # repos add in the legacy features again.
    return localrepo.locallegacypeer(self)
EOF

echo '[extensions]' >> $HGRCPATH
echo "notcapable-$CAP = `pwd`/notcapable-$CAP.py" >> $HGRCPATH