Comment 8 for bug 1754174

Adam, I'm curious about your Python statement. This only fails when running Ubiquity directly from GRUB. Loading the live system and then running Ubiquity works fine. Also, Ubiquity fails to fail for any other flavours.

Things start going south in syslog here:

Mar 7 21:40:40 lubuntu ubiquity[1244]: switched to page partman
Mar 7 21:40:44 lubuntu ubiquity: /bin/autopartition: 292: /bin/autopartition:
Mar 7 21:40:44 lubuntu ubiquity: pvs: not found
Mar 7 21:40:44 lubuntu ubiquity:
Mar 7 21:40:47 lubuntu ubiquity[1244]: debconffilter_done: ubi-partman (current: ubi-partman)
Mar 7 21:40:47 lubuntu ubiquity[1244]: Step_before = stepPartAsk

On a successful install from the live system we find a little bit different behavior:

Mar 11 01:58:43 lubuntu ubiquity[2161]: switched to page partman
Mar 11 01:58:55 lubuntu ubiquity[2161]: debconffilter_done: ubi-partman (current: ubi-partman)
Mar 11 01:58:55 lubuntu ubiquity[2161]: Step_before = stepPartAsk

Noting that /bin/autopartition is a script, I went looking for line 292, but it wasn't there. It does, however source several other scripts in /lib/partman/lib. Looking for only files with a line number 292 that includes "pvs" in it, I found:

lib/lvm-base.sh: if $(pvs --noheadings --nosuffix -o pv_name | grep -q "$device"); then

Seems like pvs is a variable created from enumerating the partman devices and looking for ones with lvm method.

I'm not sure what this all means yet, but this sure is weird.