Created attachment 715267 [details]
anaconda-tb-xxx file

Version-Release number of selected component (if applicable):
F19a TC1

How reproducible:
always

Steps to Reproduce:

0. Reach the Welcome Screen, leave default language settings
1. Enter Software Selection and select Minimal + Standard
2. Enter Installation Destination, select a disk. (i just have vda)
3. Select Custom Partitioning (leave default lvm)
4. Delete all existing partition (a previous F19a instance)
5. Click the "+" button to add a partition, /boot without specifying size
6. Select the created /boot partition (standard partition) and switch it
to btrfs (to get a /boot subvol...)
7. It will return to "standard partition" for some reason...
8. Click the "+" button to add a partition, / without specifying size
9. unknown error.

  
Actual results:
crash

Expected results:
no crashh

Additional info:

anaconda 19.12 exception report
Traceback (most recent call first):
  File "/usr/lib/python2.7/site-packages/blivet/devicefactory.py", line 362, in set_container_members
    self.storage._clean_up_member_devices(new_members,
  File "/usr/lib/python2.7/site-packages/blivet/devicefactory.py", line 489, in configure_device
    members=members, device=device)
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 1879, in factoryDevice
    mountpoint=mountpoint, label=label)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/ui/gui/spokes/custom.py", line 1714, in on_add_clicked
    disks=disks)
AttributeError: 'Blivet' object has no attribute '_clean_up_member_devices'