git-debrebase convert-from-gbp: Add ffq check

Check that the result will not count as having diverged.  This will
usually turn failures to make the ff pseudomerge into -fdiverged.

Related to #903132.

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

diff --git a/debian/changelog b/debian/changelog
index 82f6acc69c850a771fcada51fcab06ccd6508eb3..0afe46a21f64110dfdfc194f109d8e78baffa294 100644 (file)
--- a/debian/changelog
+++ b/debian/changelog
@@ -2,6 +2,9 @@ dgit (5.9~) unstable; urgency=medium
 
   * git-debrebase convert-from-gbp: Look for dgit-generated tags so we can
     usually make the new branch ff of the dgit view.  Closes:#903132.
+  * git-debrebase convert-from-gbp: Check that the result will not
+    count as having diverged.  This will usually turn failures to make
+    the ff pseudomerge into -fdiverged.  Related to #903132.
 
  --
 

diff --git a/git-debrebase b/git-debrebase
index 7b2e4f311dfbdf64813d14cb2bac92184837a6ff..f00222520e9cf2f6d230b6ebd955d5b2c7aac80b 100755 (executable)
--- a/git-debrebase
+++ b/git-debrebase
@@ -1658,7 +1658,7 @@ sub cmd_convert_from_gbp () {
        print STDERR "cannot stitch in dgit view: $@\n";
     }
 
-    snags_maybe_bail();
+    snags_maybe_bail_early();
 
     my $work;
 
@@ -1696,6 +1696,8 @@ sub cmd_convert_from_gbp () {
        }
     };
 
+    ffq_check $work;
+    snags_maybe_bail();
     update_head_checkout $old_head, $work, 'convert-from-gbp';
 }
 

diff --git a/git-debrebase.1.pod b/git-debrebase.1.pod
index d67e5570452d699851564860cc1a2e980d6ef718..273ef47dc1c13ee465d59950783a1f495b63763d 100644 (file)
--- a/git-debrebase.1.pod
+++ b/git-debrebase.1.pod
@@ -265,6 +265,10 @@ your new git-debrebase view is appropriately fast forward.
 The result is a well-formed git-debrebase interchange branch.
 The result is also fast-forward from the gbp branch.
 
+It is a snag if the new branch looks like it will have diverged,
+just as for a laundering/unstitching call to git-debrebase;
+See L</Establish the current branch's ffq-prev>, below.
+
 Note that it is dangerous not to know whether you are
 dealing with a gbp patches-unappled branch containing quilt patches,
 or a git-debrebase interchange branch.