X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=git-debrebase;h=d9b95a26850e18d0306df87f814b2a0e23cda0c4;hp=abf9157e0554fbf7e9496c030af64c9c919fe3cc;hb=13812a8ec53bd0206a5f976af211145b3029e540;hpb=49e8f18bc896d9a9dd8aedb3495854c39439c86c

diff --git a/git-debrebase b/git-debrebase
index abf9157e..d9b95a26 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 ($) {
@@ -126,8 +128,10 @@ sub in_workarea ($) {
     die $@ if $@;
 }
 
-sub fresh_workarea () {
-    $workarea = fresh_playground "$playprefix/work";
+sub fresh_workarea (;$) {
+    my ($subdir) = @_;
+    $subdir //= 'work';
+    $workarea = fresh_playground "$playprefix/$subdir";
     in_workarea sub { playtree_setup };
 }
 
@@ -152,6 +156,14 @@ 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 == $snags_summarised;
 }
@@ -160,6 +172,7 @@ sub run_deferred_updates ($) {
 
     confess 'dangerous internal error' unless all_snags_summarised();
 
+    merge_wreckage_cleaning \@deferred_updates;
     run_ref_updates_now $mrest, \@deferred_updates;
     print $_, "\n" foreach @deferred_update_messages;
 
@@ -368,14 +381,33 @@ sub gbp_pq_export ($$$) {
 #  our own patch identification algorithm?
 #  this is an alternative strategy
 
-sub merge_failed ($$) {
-    my ($wrecknotes, $emsg) = @_;
+sub merge_failed ($$;@) {
+    my ($wrecknotes, $emsg, @xmsgs) = @_;
     my @m;
     push @m, "Merge resolution failed: $emsg";
+    push @m, @xmsgs;
+
+    changedir $maindir;
+
+    my @updates;
+    merge_wreckage_cleaning \@updates;
+    run_ref_updates_now "merge failed", \@updates;
+
+    @updates = ();
+    keys %$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 { "$_\n" } @m;
+
+    # use finish rather than fail, in case we are within an eval
+    # (that can happen inside walk!)
+    print STDERR "\n";
+    print STDERR "$us: $_\n" foreach @m;
+    finish 15;
 }
 
 sub mwrecknote ($$$) {
@@ -385,6 +417,17 @@ sub mwrecknote ($$$) {
     $wrecknotes->{$reftail} = $commitish;
 }
 
+sub merge_attempt_cmd {
+    my $wrecknotes = shift @_;
+    debugcmd '+', @_;
+    $!=0; $?=-1;
+    if (system @_) {
+	merge_failed $wrecknotes,
+	    failedcmd_waitstatus(),
+	    "failed command: @_";
+    }
+}
+
 sub merge_series ($$$;@) {
     my ($newbase, $wrecknotes, $base_q, @input_qs) = @_;
     # $base_q{SeriesBase}  $input_qs[]{SeriesBase}
@@ -410,10 +453,14 @@ sub merge_series ($$$;@) {
     # $prereq{<patch filename>}               exists or not (even later)
 
     my $result;
+    my $merged_pq;
 
     my $mwrecknote = sub { &mwrecknote($wrecknotes, @_); };
 
-    local $workarea = fresh_playground "$playprefix/merge";
+    my $attempt_cmd = sub { &merge_attempt_cmd($wrecknotes, @_); };
+
+    local $workarea;
+    fresh_workarea "merge";
     my $seriesfile = "debian/patches/series";
     in_workarea sub {
 	playtree_setup();
@@ -472,11 +519,8 @@ sub merge_series ($$$;@) {
 	runcmd @git, qw(checkout -q -b merge);
 	printdebug "merge_series merging...\n";
 	my @mergecmd = (@git, qw(merge --quiet --no-edit), "p-1");
-	debugcmd '+', @mergecmd;
-	$!=0; $?=-1;
-	if (system @mergecmd) {
-	    failedcmd @mergecmd;
-	}
+
+	$attempt_cmd->(@mergecmd);
 
 	printdebug "merge_series merge ok, series...\n";
 	# We need to construct a new series file
@@ -549,10 +593,12 @@ sub merge_series ($$$;@) {
 
 	runcmd @git, qw(add), $seriesfile;
 	runcmd @git, qw(commit --quiet -m), 'Merged patch queue form';
-	$mwrecknote->('merged-patchqueue', git_rev_parse 'HEAD');
+	$merged_pq = git_rev_parse 'HEAD';
+	$mwrecknote->('merged-patchqueue', $merged_pq);
 
 	printdebug "merge_series series gbp pq import\n";
-	runcmd qw(gbp pq import);
+
+	merge_attempt_cmd($wrecknotes, qw(gbp pq import));
 
 	# OK now we are on patch-queue/merge, and we need to rebase
 	# onto the intended parent and drop the patches from each one
@@ -573,7 +619,7 @@ sub merge_series ($$$;@) {
 	    $build = cmdoutput @git, qw(hash-object -w -t commit ../mcommit);
 	}
 	$result = $build;
-	$mwrecknote->('merged-result', $result);
+	mwrecknote($wrecknotes, 'merged-result', $result);
 
 	runcmd @git, qw(update-ref refs/heads/result), $result;
 
@@ -583,7 +629,7 @@ sub merge_series ($$$;@) {
 	runcmd @git, qw(commit --allow-empty -q -m M-WORKTREE);
 	my $mdebug = git_rev_parse 'HEAD';
 	printdebug sprintf "merge_series done debug=%s\n", $mdebug;
-	$mwrecknote->('merged-debug', $mdebug);
+	mwrecknote($wrecknotes, 'merged-debug', $mdebug);
     };
     printdebug "merge_series returns $result\n";
     return $result;
@@ -1311,8 +1357,9 @@ sub walk ($;$$$) {
 	    my ($btip, $bbw, $banchor) = eval {
 		walk $ib, 0, $report, $report_lprefix.'  ';
 	    };
-	    $nomerge->("walking interchange branch merge base ($ibleaf): ".
-		       $@) if length $@;
+	    $nomerge->("walking interchange branch merge base ($ibleaf):\n".
+		       $@)
+		if length $@;
 
 	    $mwrecknote->("mergebase-laundered", $btip);
 	    $mwrecknote->("mergebase-breakwater", $bbw);