templater: strictly parse leading backslashes of '{' (issue4569) (BC)
Because double backslashes are processed as a string escape sequence, '\\{'
should start the template syntax. On the other hand, r'' disables any sort
of \-escapes, so r'\{' can go either way, never start the template syntax
or always start it. I simply chose the latter, which means r'\{' is the same
as '\\{'.
#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 ..