tests/test-update-reverse.t

largefiles: fix a traceback in lfconvert if a largefile is missing (issue3519)

The largefile may be missing for various reasons, including that a remote
repository was cloned without the --all-largefiles option.  Therefore, it seems
reasonable to attempt to download the missing files and failing that, abort and
indicate the affected file and revision so the user can manually fix the
problem.

  $ hg init

  $ touch a
  $ hg add a
  $ hg commit -m "Added a"

  $ touch main
  $ hg add main
  $ hg commit -m "Added main"
  $ hg checkout 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

'main' should be gone:

  $ ls
  a

  $ touch side1
  $ hg add side1
  $ hg commit -m "Added side1"
  created new head
  $ touch side2
  $ hg add side2
  $ hg commit -m "Added side2"

  $ hg log
  changeset:   3:91ebc10ed028
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added side2
  
  changeset:   2:b932d7dbb1e1
  parent:      0:c2eda428b523
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added side1
  
  changeset:   1:71a760306caf
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added main
  
  changeset:   0:c2eda428b523
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added a
  

  $ hg heads
  changeset:   3:91ebc10ed028
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added side2
  
  changeset:   1:71a760306caf
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added main
  
  $ ls
  a
  side1
  side2

  $ hg update --debug -C 1
  resolving manifests
   overwrite: True, partial: False
   ancestor: 91ebc10ed028+, local: 91ebc10ed028+, remote: 71a760306caf
   side2: other deleted -> r
   side1: other deleted -> r
   main: remote created -> g
  updating: side1 1/3 files (33.33%)
  removing side1
  updating: side2 2/3 files (66.67%)
  removing side2
  updating: main 3/3 files (100.00%)
  getting main
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ ls
  a
  main