filemerge: store error messages in module variables Copytracing may be disabled because it's too slow (see experimental.disablecopytrace config option). In that case user may get errors like 'local changed FILE which other deleted'. It would be nice to give user a hint to rerun command with `--config experimental.disablecopytrace=False`. To make it possible let's extract error message to variables so that extension may overwrite them.

#require execbit

  $ hg init repo
  $ cd repo
  $ echo foo > foo
  $ chmod 644 foo
  $ hg ci -qAm '644'

  $ chmod 755 foo
  $ hg ci -qAm '755'

reverting to rev 0

  $ hg revert -a -r 0
  reverting foo
  $ hg st
  M foo
  $ hg diff --git
  diff --git a/foo b/foo
  old mode 100755
  new mode 100644

  $ cd ..