view tests/test-dirstate-backup.t @ 39127:95bd19f60957

overlayworkingctx: fix exception in metadata-only inmemory merges (issue5960)

If there was a metadata-only mutation, such as +x or -x on a file, we would
create a cache entry with None for data, and this would cause problems later on
when some code tried to run fctx.data() or similar, and was expecting a string.

My original fix for this involved passing data=self._wrappedctx[path].data() in
setflags(), but this version seems slightly better - this way, if we ever call
write() and then call setflags(), we don't destroy the data that we wrote that's
in the cache. I haven't verified that other fields aren't destroyed, such as
date or flags :)

Differential Revision: https://phab.mercurial-scm.org/D4287

Set up

  $ hg init repo
  $ cd repo

Try to import an empty patch

  $ hg import --no-commit - <<EOF
  > EOF
  applying patch from stdin
  abort: stdin: no diffs found
  [255]

No dirstate backups are left behind

  $ ls .hg/dirstate* | sort
  .hg/dirstate