Dpkg::Source::Package: Add ‘.mnt-ignore’ to the default ignore lists

Closes: #855450
Signed-off-by: Guillem Jover <guillem@debian.org>

debian/changelog

@@ -12,6 +12,9 @@ dpkg (1.18.23) UNRELEASED; urgency=medium
       for unknown executable formats instead of relying on objdump doing so.
     - Do not parse bogus ELF binaries in Dpkg::Shlibs::Objdump::get_format().
       Reported by Niels Thykier <niels@thykier.net>.
+    - Add ‘.mnt-ignore’ to the default ignore lists in Dpkg::Source::Package,
+      as we were already ignoring the ‘_MTN’ pathnames. Closes: #855450
+      Thanks to Nicolas Boulenguez <nicolas@debian.org>.
   * Documentation:
     - Clarify the requirements for deb-conffile(5) pathnames. Closes: #854417
       Proposed by Dieter Adriaenssens <dieter.adriaenssens@gmail.com>.

scripts/Dpkg/Source/Package.pm

@@ -67,7 +67,7 @@ my $diff_ignore_default_regex = '
 # Ignore baz-style junk files or directories
 (?:^|/),,.*(?:$|/.*$)|
 # File-names that should be ignored (never directories)
-(?:^|/)(?:DEADJOE|\.arch-inventory|\.(?:bzr|cvs|hg|git)ignore)$|
+(?:^|/)(?:DEADJOE|\.arch-inventory|\.(?:bzr|cvs|hg|git|mtn-)ignore)$|
 # File or directory names that should be ignored
 (?:^|/)(?:CVS|RCS|\.deps|\{arch\}|\.arch-ids|\.svn|
 \.hg(?:tags|sigs)?|_darcs|\.git(?:attributes|modules|review)?|
@@ -112,6 +112,7 @@ our @tar_ignore_default_pattern = qw(
 .hgsigs
 .hgtags
 .mailmap
+.mtn-ignore
 .shelf
 .svn
 CVS