Improve error message for non-fast-forward push. Closes: #720896.

2 files changed, 5 insertions, 1 deletions

diff --git a/debian/changelog b/debian/changelog
index d550745..a30e469 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -2,6 +2,7 @@ dgit (0.12) unstable; urgency=low
 
   * Cope with packages with epoch.  Closes: #720897.
   * Add Closes line for #720595 to changelog entry for 0.11.
+  * Improve error message for non-fast-forward push.  Closes: #720896.
 
  --
 
diff --git a/dgit b/dgit
index f582be0..71b0423 100755
--- a/dgit
+++ b/dgit
@@ -984,7 +984,10 @@ sub cmd_push {
 	git_fetch_us();
     }
     if (fetch_from_archive()) {
-	is_fast_fwd(lrref(), 'HEAD') or die;
+	is_fast_fwd(lrref(), 'HEAD') or
+	    fail "dgit push: HEAD is not a descendant".
+	        " of the archive's version.\n".
+		"$us: To overwrite it, use git-merge -s ours ".lrref().".";
     } else {
 	$new_package or
 	    fail "package appears to be new in this suite;".