Improve "cannot represent change" message

Print the git old and new modes too.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

3 files changed, 4 insertions, 2 deletions

diff --git a/debian/changelog b/debian/changelog
index 64ed65c..846fe23 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -4,6 +4,8 @@ dgit (2.13~) unstable; urgency=medium
     --include-removal to dpkg-source, and tolerating it when we do our
     quilt fixup analysis.  dpkg-source has supported this since at least
     stretch.  Closes:#848901.
+  * Improve "cannot represent change" message: print the git old and new
+    modes too.
 
  --
 
diff --git a/dgit b/dgit
index 9a8d221..acb4563 100755
--- a/dgit
+++ b/dgit
@@ -4509,7 +4509,7 @@ sub quiltify_trees_differ ($$;$$$) {
 	    };
 	    if ($@) {
 		local $/="\n"; chomp $@;
-		push @$unrepres, [ $f, $@ ];
+		push @$unrepres, [ $f, "$@ ($oldmode->$newmode)" ];
 	    }
 	}
 
diff --git a/tests/tests/unrepresentable b/tests/tests/unrepresentable
index 9dd2111..5b3e139 100755
--- a/tests/tests/unrepresentable
+++ b/tests/tests/unrepresentable
@@ -21,7 +21,7 @@ badly-1 () {
 
 badly-2 () {
 	git commit -m "Commit wrongness $wrongfn ($wrongmsg)"
-	t-expect-fail "cannot represent change: $wrongmsg: $wrongfn" \
+	t-expect-fail E:"cannot represent change: $wrongmsg .*: $wrongfn" \
 	attempt
 }