X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=git-debrebase;h=213728023f249305eb873722d305f3168a1cb0c4;hp=7c69c4c0b2b970eeeee8eb09edae9488dbc3a6bc;hb=eec3f8c097bdb3f03499c9228f42d5cd2ce65786;hpb=8c4cbc9eafaff67f8029512a0b5e710fb5278390

diff --git a/git-debrebase b/git-debrebase
index 7c69c4c0..21372802 100755
--- a/git-debrebase
+++ b/git-debrebase
@@ -55,6 +55,8 @@ our ($opt_defaultcmd_interactive);
 
 our $us = qw(git-debrebase);
 
+our $wrecknoteprefix = 'refs/debrebase-wreckage';
+
 $|=1;
 
 sub badusage ($) {
@@ -131,12 +133,35 @@ sub fresh_workarea () {
     in_workarea sub { playtree_setup };
 }
 
+sub run_ref_updates_now ($$) {
+    my ($mrest, $updates) = @_;
+    # @$updates is a list of lines for git-update-ref, without \ns
+
+    my @upd_cmd = (git_update_ref_cmd "debrebase: $mrest", qw(--stdin));
+    debugcmd '>|', @upd_cmd;
+    open U, "|-", @upd_cmd or die $!;
+    foreach (@$updates) {
+	printdebug ">= ", $_, "\n";
+	print U $_, "\n" or die $!;
+    }
+    printdebug ">\$\n";
+    close U or failedcmd @upd_cmd;
+}
+
 our $snags_forced = 0;
 our $snags_tripped = 0;
 our $snags_summarised = 0;
 our @deferred_updates;
 our @deferred_update_messages;
 
+sub merge_wreckage_cleaning ($) {
+    my ($updates) = @_;
+    git_for_each_ref("$wrecknoteprefix/*", sub {
+	my ($objid,$objtype,$fullrefname,$reftail) = @_;
+	push @$updates, "delete $fullrefname";
+    });
+}
+
 sub all_snags_summarised () {
     $snags_forced + $snags_tripped == $snags_summarised;
 }
@@ -145,16 +170,8 @@ sub run_deferred_updates ($) {
 
     confess 'dangerous internal error' unless all_snags_summarised();
 
-    my @upd_cmd = (git_update_ref_cmd "debrebase: $mrest", qw(--stdin));
-    debugcmd '>|', @upd_cmd;
-    open U, "|-", @upd_cmd or die $!;
-    foreach (@deferred_updates) {
-	printdebug ">= ", $_, "\n";
-	print U $_, "\n" or die $!;
-    }
-    printdebug ">\$\n";
-    close U or failedcmd @upd_cmd;
-
+    merge_wreckage_cleaning \@deferred_updates;
+    run_ref_updates_now $mrest, \@deferred_updates;
     print $_, "\n" foreach @deferred_update_messages;
 
     @deferred_updates = ();
@@ -362,6 +379,34 @@ sub gbp_pq_export ($$$) {
 #  our own patch identification algorithm?
 #  this is an alternative strategy
 
+sub merge_failed ($$) {
+    my ($wrecknotes, $emsg) = @_;
+    my @m;
+    push @m, "Merge resolution failed: $emsg";
+
+    changedir $maindir;
+
+    my @updates;
+    merge_wreckage_cleaning \@updates;
+    keys %$wrecknotes;
+    while (my ($k,$v) = each %$wrecknotes) {
+	push @updates, "create $wrecknoteprefix/$k $v";
+    }
+    run_ref_updates_now "merge failed", \@updates;
+    push @m, "Wreckage left in $wrecknoteprefix/*.";
+
+    push @m, "See git-debrebase(1) section FAILED MERGES for suggestions.";
+    # ^ xxx this section does not yet exist
+    fail join '', map { "$_\n" } @m;
+}
+
+sub mwrecknote ($$$) {
+    my ($wrecknotes, $reftail, $commitish) = @_;
+    confess unless defined $commitish;
+    printdebug "mwrecknote $reftail $commitish\n";
+    $wrecknotes->{$reftail} = $commitish;
+}
+
 sub merge_series ($$$;@) {
     my ($newbase, $wrecknotes, $base_q, @input_qs) = @_;
     # $base_q{SeriesBase}  $input_qs[]{SeriesBase}
@@ -388,10 +433,7 @@ sub merge_series ($$$;@) {
 
     my $result;
 
-    my $mwrecknote = sub {
-	my ($reftail, $commitish) = @_;
-	$wrecknotes->{$reftail} = $commitish;
-    };
+    my $mwrecknote = sub { &mwrecknote($wrecknotes, @_); };
 
     local $workarea = fresh_playground "$playprefix/merge";
     my $seriesfile = "debian/patches/series";
@@ -423,7 +465,7 @@ sub merge_series ($$$;@) {
                 " $q->{SeriesTip}]"
             ];
 	    printdebug "merge_series  pec $pec ";
-	    runcmd @git, qw(rm -q --cached), $seriesfile;
+	    runcmd @git, qw(rm -q --ignore-unmatch --cached), $seriesfile;
 	    $pec = make_commit [ $pec ], [
                 "Drop series file from $s to avoid merge trouble",
                 "[git-debrebase merge-innards patch-queue prep:".
@@ -446,7 +488,7 @@ sub merge_series ($$$;@) {
 	    printdebug "pec' $pec\n";
             runcmd @git, qw(reset -q --hard), $pec;
 	    $q->{MR}{PEC} = $pec;
-	    $mwrecknote->("$q->{LeftRight}-patchqueue");
+	    $mwrecknote->("$q->{LeftRight}-patchqueue", $pec);
 	}
 	# now, because of reverse, we are on $input_q->{MR}{OQC}
 	runcmd @git, qw(checkout -q -b merge);
@@ -1036,18 +1078,17 @@ sub walk ($;$$$) {
     };
 
     my $nomerge = sub {
-	fail "something useful about failed merge attempt @_ xxx".Dumper($cl);
+	my ($emsg) = @_;
+	merge_failed $cl->{MergeWreckNotes}, $emsg;
     };
 
-    my $mwrecknote = sub {
-	my ($reftail, $commitish) = @_;
-	$cl->{MergeWreckNotes}{$reftail} = $commitish;
-    };
+    my $mwrecknote = sub { &mwrecknote($cl->{MergeWreckNotes}, @_); };
 
     my $last_anchor;
 
     for (;;) {
 	$cl = classify $cur;
+	$cl->{MergeWreckNotes} //= {};
 	my $ty = $cl->{Type};
 	my $st = $cl->{SubType};
 	$prline->("$cl->{CommitId} $cl->{Type}");