git-debrebase: Refuse to start conversion if ffq-prev exists

[dgit.git] / git-debrebase

diff --git a/git-debrebase b/git-debrebase
index 36f73d70e75767a381d605b59a8285bbbfa26585..059d02b546e8b33020ca7bdb48cacd7972d6e660 100755 (executable)
--- a/git-debrebase
+++ b/git-debrebase
@@ -50,7 +50,7 @@ usages:
 See git-debrebase(1), git-debrebase(5), dgit-maint-debrebase(7) (in dgit).
 END
 
-our ($opt_force, $opt_noop_ok, @opt_anchors);
+our ($opt_force, $opt_noop_ok, $opt_merges, @opt_anchors);
 our ($opt_defaultcmd_interactive);
 
 our $us = qw(git-debrebase);
@@ -196,6 +196,8 @@ sub get_tree ($;$$) {
        return () if $type eq 'missing';
     }
 
+    confess "get_tree needs object not $x ?" unless $x =~ m{^[0-9a-f]+\:};
+
     our (@get_tree_memo, %get_tree_memo);
     my $memo = $get_tree_memo{$x};
     return @$memo if $memo;
@@ -426,6 +428,17 @@ sub any_snags () {
     return $snags_forced || $snags_tripped;
 }
 
+sub ffq_prev_branchinfo () {
+    my $current = git_get_symref();
+    return gdr_ffq_prev_branchinfo($current);
+}
+
+sub record_gdrlast ($$;$) {
+    my ($gdrlast, $newvalue, $oldvalue) = @_;
+    $oldvalue ||= $git_null_obj;
+    push @deferred_updates, "update $gdrlast $newvalue $oldvalue";
+}
+
 sub gbp_pq_export ($$$) {
     my ($bname, $base, $tip) = @_;
     # must be run in a workarea.  $bname and patch-queue/$bname
@@ -681,6 +694,8 @@ sub merge_series_patchqueue_convert ($$$) {
        runcmd @git, qw(checkout -q -b mergec), $merged_pq;
 
        merge_attempt_cmd($wrecknotes, qw(gbp pq import));
+       # MERGE-TODO consider git-format-patch etc. instead,
+       # since gbp pq doesn't always round-trip :-/
 
        # OK now we are on patch-queue/merge, and we need to rebase
        # onto the intended parent and drop the patches from each one
@@ -985,7 +1000,7 @@ sub classify ($) {
        return $unknown->("octopus merge");
     }
 
-    if (!$ENV{GIT_DEBREBASE_EXPERIMENTAL_MERGE}) {
+    if (!$opt_merges) {
        return $unknown->("general two-parent merge");
     }
 
@@ -1731,11 +1746,6 @@ sub cmd_analyse () {
     STDOUT->error and die $!;
 }
 
-sub ffq_prev_branchinfo () {
-    my $current = git_get_symref();
-    return gdr_ffq_prev_branchinfo($current);
-}
-
 sub ffq_check ($;$$) {
     # calls $ff and/or $notff zero or more times
     # then returns either (status,message) where status is
@@ -1877,8 +1887,7 @@ sub stitch ($$$$$) {
            # ffq-prev is ahead of us, and the only tree changes it has
            # are possibly addition of things in debian/patches/.
            # Just wind forwards rather than making a pointless pseudomerge.
-           push @deferred_updates,
-               "update $gdrlast $ffq_prev_commitish $git_null_obj";
+           record_gdrlast $gdrlast, $ffq_prev_commitish;
            update_head_checkout $old_head, $ffq_prev_commitish,
                "stitch (fast forward)";
            return;
@@ -1891,7 +1900,7 @@ sub stitch ($$$$$) {
        'Declare fast forward / record previous work',
         "[git-debrebase pseudomerge: $prose]",
     ];
-    push @deferred_updates, "update $gdrlast $new_head $git_null_obj";
+    record_gdrlast $gdrlast, $new_head;
     update_head $old_head, $new_head, "stitch: $prose";
 }
 
@@ -2401,6 +2410,22 @@ sub check_series_has_all_patches ($) {
     }
 }
 
+sub begin_convert_from () {
+    my $head = get_head();
+    my ($ffqs, $ffqm, $symref, $ffq_prev, $gdrlast) = ffq_prev_branchinfo();
+
+    fail "ffq-prev exists, this is already managed by git-debrebase!"
+       if $ffq_prev && git_get_ref $ffq_prev;
+    return ($head, undef);
+}
+
+sub complete_convert_from ($$$$) {
+    my ($old_head, $new_head, $gi, $mrest) = @_;
+    ffq_check $new_head;
+    snags_maybe_bail();
+    update_head_checkout $old_head, $new_head, $mrest;
+}
+
 sub cmd_convert_from_gbp () {
     badusage "want only 1 optional argument, the upstream git commitish"
        unless @ARGV<=1;
@@ -2415,7 +2440,7 @@ sub cmd_convert_from_gbp () {
     my $upstream =
        resolve_upstream_version($upstream_spec, $upstream_version);
 
-    my $old_head = get_head();
+    my ($old_head, $gdrlastinfo) = begin_convert_from();
 
     my $upsdiff = get_differs $upstream, $old_head;
     if ($upsdiff & D_UPS) {
@@ -2529,9 +2554,7 @@ END
        }
     };
 
-    ffq_check $work;
-    snags_maybe_bail();
-    update_head_checkout $old_head, $work, 'convert-from-gbp';
+    complete_convert_from $old_head, $work, $gdrlastinfo, 'convert-from-gbp';
     print <<END or die $!;
 git-debrebase: converted from patched-unapplied (gbp) branch format, OK
 END
@@ -2591,7 +2614,7 @@ sub cmd_convert_from_dgit_view () {
                         };
     }
 
-    my $head = get_head();
+    my ($head, $gdrlastinfo) = begin_convert_from();
 
     if (!$always) {
        my $troubles = 0;
@@ -2747,9 +2770,7 @@ END
 
     printf STDERR "Yes, will base new branch on %s\n", $result->{Source};
 
-    ffq_check $result->{Result};
-    snags_maybe_bail();
-    update_head_checkout $head, $result->{Result},
+    complete_convert_from $head, $result->{Result}, $gdrlastinfo,
        'convert-from-dgit-view';
 }
 
@@ -2850,6 +2871,7 @@ getoptions_main
           'anchor=s' => \@opt_anchors,
           '--dgit=s' => \($dgit[0]),
           'force!',
+          'experimental-merge-resolution!', \$opt_merges,
           '-i:s' => sub {
               my ($opt,$val) = @_;
               badusage "git-debrebase: no cuddling to -i for git-rebase"