git-debrebase: Do not bail making patches if there aren't any.

[dgit.git] / git-debrebase

diff --git a/git-debrebase b/git-debrebase
index 771410ef1350443ee703f45434e86fd8ae2c6e74..7c69c4c0b2b970eeeee8eb09edae9488dbc3a6bc 100755 (executable)
--- a/git-debrebase
+++ b/git-debrebase
@@ -344,7 +344,7 @@ sub gbp_pq_export ($$$) {
        { local ($!,$?); copy('../gbp-pq-err', \*STDERR); }
        failedcmd @gbp_cmd;
     }
-    runcmd @git, qw(add -f debian/patches);
+    runcmd @git, qw(add -f debian/patches) if stat_exists 'debian/patches';
 }
 
 
@@ -362,8 +362,8 @@ sub gbp_pq_export ($$$) {
 #  our own patch identification algorithm?
 #  this is an alternative strategy
 
-sub merge_series ($$;@) {
-    my ($newbase, $base_q, @input_qs) = @_;
+sub merge_series ($$$;@) {
+    my ($newbase, $wrecknotes, $base_q, @input_qs) = @_;
     # $base_q{SeriesBase}  $input_qs[]{SeriesBase}
     # $base_q{SeriesTip}   $input_qs[]{SeriesTip}
     # ^ specifies several patch series (currently we only support exactly 2)
@@ -388,6 +388,11 @@ sub merge_series ($$;@) {
 
     my $result;
 
+    my $mwrecknote = sub {
+       my ($reftail, $commitish) = @_;
+       $wrecknotes->{$reftail} = $commitish;
+    };
+
     local $workarea = fresh_playground "$playprefix/merge";
     my $seriesfile = "debian/patches/series";
     in_workarea sub {
@@ -441,6 +446,7 @@ sub merge_series ($$;@) {
            printdebug "pec' $pec\n";
             runcmd @git, qw(reset -q --hard), $pec;
            $q->{MR}{PEC} = $pec;
+           $mwrecknote->("$q->{LeftRight}-patchqueue");
        }
        # now, because of reverse, we are on $input_q->{MR}{OQC}
        runcmd @git, qw(checkout -q -b merge);
@@ -522,7 +528,8 @@ sub merge_series ($$;@) {
        }
 
        runcmd @git, qw(add), $seriesfile;
-       runcmd @git, qw(commit --quiet -m), 'Merged series';
+       runcmd @git, qw(commit --quiet -m), 'Merged patch queue form';
+       $mwrecknote->('merged-patchqueue', git_rev_parse 'HEAD');
 
        printdebug "merge_series series gbp pq import\n";
        runcmd qw(gbp pq import);
@@ -546,14 +553,17 @@ sub merge_series ($$;@) {
            $build = cmdoutput @git, qw(hash-object -w -t commit ../mcommit);
        }
        $result = $build;
+       $mwrecknote->('merged-result', $result);
+
        runcmd @git, qw(update-ref refs/heads/result), $result;
 
        runcmd @git, qw(checkout -q -b debug);
        runcmd @git, qw(commit --allow-empty -q -m M-INDEX);
        runcmd @git, qw(add .);
        runcmd @git, qw(commit --allow-empty -q -m M-WORKTREE);
-       printdebug sprintf "merge_series done debug=%s\n",
-           git_rev_parse 'HEAD';
+       my $mdebug = git_rev_parse 'HEAD';
+       printdebug sprintf "merge_series done debug=%s\n", $mdebug;
+       $mwrecknote->('merged-debug', $mdebug);
     };
     printdebug "merge_series returns $result\n";
     return $result;
@@ -1029,6 +1039,11 @@ sub walk ($;$$$) {
        fail "something useful about failed merge attempt @_ xxx".Dumper($cl);
     };
 
+    my $mwrecknote = sub {
+       my ($reftail, $commitish) = @_;
+       $cl->{MergeWreckNotes}{$reftail} = $commitish;
+    };
+
     my $last_anchor;
 
     for (;;) {
@@ -1178,6 +1193,8 @@ sub walk ($;$$$) {
 
            my $ps = $cl->{Parents};
 
+           $mwrecknote->('vanilla-merge', $cl->{CommitId});
+
            foreach my $p (@$ps) {
                $prline->(" VanillaMerge ".$p->{Ix});
                $prprdelim->();
@@ -1188,6 +1205,17 @@ sub walk ($;$$$) {
                $p->{Breakwater} = $p->{SeriesBase} = $pbw;
                $p->{Anchor} = $panchor;
 
+               my $lr = $p->{LeftRight} = (qw(left right))[$p->{Ix}];
+               $mwrecknote->("$lr-input", $p->{CommitId});
+
+               my $mwrecknote_parent = sub {
+                   my ($which) = @_;
+                   $mwrecknote->("$lr-".(lc $which), $p->{$which});
+               };
+               $mwrecknote_parent->('Laundered');
+               $mwrecknote_parent->('Breakwater');
+               $mwrecknote_parent->('Anchor');
+
                $best_anchor = $panchor if
                    !defined $best_anchor or
                    is_fast_fwd $best_anchor, $panchor;
@@ -1196,6 +1224,8 @@ sub walk ($;$$$) {
                    " p=$panchor\n";
            }
 
+           $mwrecknote->('result-anchor', $best_anchor);
+
            foreach my $p (@$ps) {
                $prline->(" VanillaMerge ".$p->{Ix});
                if (!is_fast_fwd $p->{Anchor}, $best_anchor) {
@@ -1242,24 +1272,38 @@ sub walk ($;$$$) {
             @ibs or confess 'internal error, expected anchor at least ?';
 
            my $ib;
+           my $ibleaf;
            foreach my $tibix (0..$#ibs) {
                my $tib = $ibs[$tibix];
                my $ff = is_fast_fwd $bwb, $tib;
+               my $ok = !$ff ? 'rej' : $ib ? 'extra' : 'ok';
+               my $tibleaf = "interchange-mbcand-$ok-$tibix";
+               $mwrecknote->($tibleaf, $tib);
                next unless $ff;
                next if $ib;
                $ib = $tib;
+               $ibleaf = $tibleaf;
            }
 
            $ib or $nomerge->("no suitable interchange merge base");
 
            $prline->("  VanillaMerge Base");
            $prprdelim->();
-           my ($btip, $bbw, $banchor) =
+           my ($btip, $bbw, $banchor) = eval {
                walk $ib, 0, $report, $report_lprefix.'  ';
+           };
+           $nomerge->("walking interchange branch merge base ($ibleaf): ".
+                      $@) if length $@;
+
+           $mwrecknote->("mergebase-laundered", $btip);
+           $mwrecknote->("mergebase-breakwater", $bbw);
+           $mwrecknote->("mergebase-anchor", $banchor);
 
            my $ibinfo = { SeriesTip => $btip,
                           SeriesBase => $bbw,
-                          Anchor => $banchor };
+                          Anchor => $banchor,
+                          LeftRight => 'mergebase' };
+
            $bbw eq $bwb
                or $nomerge->("interchange merge-base ($ib)'s".
                              " breakwater ($bbw)".
@@ -1360,7 +1404,7 @@ sub walk ($;$$$) {
            } elsif ($method eq 'MergeMergeSeries') {
                print "Running merge resolution for $cl->{CommitId}...\n";
                $build = merge_series
-                   $build,
+                   $build, $cl->{MergeWreckNotes},
                    $cl->{MergeInterchangeBaseInfo},
                    @{ $cl->{Parents} };
                $last_anchor = $cl->{MergeBestAnchor};