Comment 5 for bug 2063192

After investigating, here are my observations:

1. Partitions should not be automounted by gnome. There is supposed to be code in the desktop installer to prevent this from happening. I wonder if a time issue is causing the partitions to be automounted before the code is executed?

2. There is something inconsistent between sdc in the list of guided reformat scenarios but not sdb. IMO since both devices have a mounted filesystem (one at the disk level and the other at a partition level) they should both be excluded from the guided reformat scenarios.

* sdb is not considered a valid boot disk
  -> get_boot_device_plan(Disk(id=sdb)._reformatted()) returns False
* sdc is considered a valid boot disk
  -> get_boot_device_plan(Disk(id=sdc)._reformatted()) returns True

(the _reformatted() method returns a new instance of the disk descriptor with all partitions /that are not in use/ removed)

* For sdb, such disk would have partitions=[Partition(id=sdb1)] since sdb1 is in use
* For sdc, such disk would have partitions=[] since it has no partition.

I believe the get_boot_device_plan() forgets to look if the disk is "in use" ; i.e., if it contains a filesystem (not in a partition) that is already mounted.