tests/test-empty.t

extdiff: copy back execbit-only changes to the working directory

Some tools like BeyondCompare allow the file mode to be changed.  The change
was previously applied if the content of the file changed (either according to
size or mtime), but was not being copied back for a mode-only change.  That
would seem to indicate handling this in an 'elif' branch, but I opted not to in
order to avoid copying back the mode without the content changes when mtime and
size are unchanged.  (Yes, that's a rare corner case, but all the more reason
not to have a subtle difference in behavior.)

The only way I can think to handle this undetected change is to set each file in
the non-wdir() snapshot to readonly, and check for that attribute (as well as
mtime) when deciding to copy back.  That would avoid the overhead of copying the
whole file when only the mode changed.  But a chmod in a diff tool is likely
rare.  See also affd753ddaf1.

Create an empty repo:

  $ hg init a
  $ cd a

Try some commands:

  $ hg log
  $ hg grep wah
  [1]
  $ hg manifest
  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  0 files, 0 changesets, 0 total revisions

Check the basic files created:

  $ ls .hg
  00changelog.i
  requires
  store

Should be empty:

  $ ls .hg/store

Poke at a clone:

  $ cd ..
  $ hg clone a b
  updating to branch default
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd b
  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  0 files, 0 changesets, 0 total revisions
  $ ls .hg
  00changelog.i
  hgrc
  requires
  store

Should be empty:

  $ ls .hg/store

  $ cd ..