convert: Using --dest-type svn crashed, if the source repo used tags.
The convert extension requires puttags(self, tags) to return a sequence
for a multi-variable assignment. If puttags implicitly returns None,
the code will break when trying to un-pack None for assignment.
#!/bin/sh
mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m test -d "1000000 0"
rm .hg/requires
hg tip
echo indoor-pool > .hg/requires
hg tip
true