Comment # 2 on bug 1099762 from Stefan Hundhammer

From the y2log:

2018-06-30 14:48:36 <1> install(3227) [Ruby] proposal/space_maker.rb

  Step 1 - resize_windows!
  Step 2 - delete_partitions!
  Deleting partitions to make space
  Deletion candidates (linux): []
  Step 3 - delete_partitions!
  Deleting partitions to make space
  Deletion candidates (other): []
  Step 4 - resize_windows!
  Step 5 - delete_partitions!
  Deleting partitions to make space
  Deletion candidates (windows): []
  Step 6 - delete_disk_content
  BEGIN delete_disk_content with disk /dev/vda
  Checking if the disk /dev/vda has a partition table
  END delete_disk_content

2018-06-30 14:48:36 <1> install(3227) [Ruby] y2storage/guided_proposal.rb:138
Failed to make a proposal using root device /dev/vda: Y2Storage::Error

2018-06-30 14:48:36 <3> install(3227) [Ruby] initial_strategies/base.rb:71
Proposal failed: #<Y2Storage::Error: Y2Storage::Error>

2018-06-30 14:48:36 <2> install(3227) [Ruby] yast/builtins.rb:586 tostring
builtin called on wrong type Class

2018-06-30 14:48:36 <3> install(3227) [Ruby] yast/wfm.rb:253
Client /mounts/mp_0001/usr/share/YaST2/clients/partitions_proposal.rb
failed with
'undefined method `safe_copy' for nil:NilClass' (NoMethodError).

Backtrace:

...lib/y2storage/storage_manager.rb:390:in `copy_to_staging'
...lib/y2storage/storage_manager.rb:252:in `proposal='
...lib/y2storage/clients/partitions_proposal.rb:166:in `ensure_proposed'
...lib/y2storage/clients/partitions_proposal.rb:58:in `initialize'
...clients/partitions_proposal.rb:25:in `new'
...clients/partitions_proposal.rb:25:in `<top (required)>'
.../wfm.rb:313:in `eval'
.../wfm.rb:313:in `run_client'
.../wfm.rb:206:in `call_builtin'
.../wfm.rb:206:in `call_builtin_wrapper'
.../wfm.rb:195:in `CallFunction'
.../installation/proposal_store.rb:206:in `description_for'
.../installation/proposal_store.rb:151:in `block in proposal_names'
.../installation/proposal_store.rb:151:in `select'
.../installation/proposal_store.rb:151:in `proposal_names'
.../installation/proposal_runner.rb:619:in `load_matching_submodules_list'
.../installation/proposal_runner.rb:116:in `run'
.../installation/proposal_runner.rb:41:in `run'
.../clients/inst_proposal.rb:24:in `<top (required)>'