I traced this to the bzr_log method in the plugin, and patching that seems to fix it. The plugin just needs to parse the input little bit differently.
--liw
+
+> Patch applied, [[done]] (but, it would be good if it could be tested with
+> an older bzr, and it's a pity bzr's human-targeted log has to be parsed,
+> I assume there is no machine-targeted version?) --[[Joey]]
+
+ From fb897114124e627fd3acf5af8e784c9a77419a81 Mon Sep 17 00:00:00 2001
+ From: Lars Wirzenius <liw@liw.fi>
+ Date: Sun, 4 Apr 2010 21:05:07 +1200
+ Subject: [PATCH] Fix bzr plugin to work with bzr 2.0.
+
+ The output of "bzr log" seems to have changed a bit, so we change the
+ parsing accordingly. This has not been tested with earlier versions of
+ bzr.
+
+ Several problems seemed to occur, all in the bzr_log subroutine:
+
+ 1. The @infos list would contain an empty hash, which would confuse the
+ rest of the program.
+ 2. This was because bzr_log would push an empty anonymous hash to the
+ list whenever it thought a new record would start.
+ 3. However, a new record marker (now?) also happens at th end of bzr log
+ output.
+ 4. Now we collect the record to a hash that gets pushed to the list only
+ if it is not empty.
+ 5. Also, sometimes bzr log outputs "revno: 1234 [merge]", so we catch only
+ the revision number.
+ 6. Finally, there may be non-headers at the of the output, so we ignore
+ those.
+ ---
+ IkiWiki/Plugin/bzr.pm | 23 ++++++++++++++++-------
+ 1 files changed, 16 insertions(+), 7 deletions(-)
+
+ diff --git a/IkiWiki/Plugin/bzr.pm b/IkiWiki/Plugin/bzr.pm
+ index 1ffdc23..e813331 100644
+ --- a/IkiWiki/Plugin/bzr.pm
+ +++ b/IkiWiki/Plugin/bzr.pm
+ @@ -73,28 +73,37 @@ sub bzr_log ($) {
+ my @infos = ();
+ my $key = undef;
+
+ + my $hash = {};
+ while (<$out>) {
+ my $line = $_;
+ my ($value);
+ if ($line =~ /^message:/) {
+ $key = "message";
+ - $infos[$#infos]{$key} = "";
+ + $$hash{$key} = "";
+ }
+ elsif ($line =~ /^(modified|added|renamed|renamed and modified|removed):/) {
+ $key = "files";
+ - unless (defined($infos[$#infos]{$key})) { $infos[$#infos]{$key} = ""; }
+ + unless (defined($$hash{$key})) { $$hash{$key} = ""; }
+ }
+ elsif (defined($key) and $line =~ /^ (.*)/) {
+ - $infos[$#infos]{$key} .= "$1\n";
+ + $$hash{$key} .= "$1\n";
+ }
+ elsif ($line eq "------------------------------------------------------------\n") {
+ + if (keys %$hash) {
+ + push (@infos, $hash);
+ + }
+ + $hash = {};
+ $key = undef;
+ - push (@infos, {});
+ }
+ - else {
+ + elsif ($line =~ /: /) {
+ chomp $line;
+ - ($key, $value) = split /: +/, $line, 2;
+ - $infos[$#infos]{$key} = $value;
+ + if ($line =~ /^revno: (\d+)/) {
+ + $key = "revno";
+ + $value = $1;
+ + } else {
+ + ($key, $value) = split /: +/, $line, 2;
+ + }
+ + $$hash{$key} = $value;
+ }
+ }
+ close $out;
+ --
+ 1.7.0