Hello Monks! As usual I'm back with a bit of Moose related craziness that's threatening my limited sanity reserve. I'd like to see if some of you kind folks have some insight :)

So I have the following (code is cut down here). This is all from my SVN::Handle package. This package is mostly wrappers around SVN::Client methods and has a SVN::Client object it delegates to. Basic idea is to call $handle->commit with the log message and arguments, and it does the appropriate stuff to take care of setting the log callback correctly and all for you. The $self->client_obj returns the underlying SVN::Client object.

has 'log_message' => (
    isa => 'Str',
    is => 'ro',
    writer => '_set_log_message',
    clearer => '_clear_log_message'
);

sub commit {
    my ($self, $msg, @args) = @_;

    print STDERR "COMMIT CALLED WITH MSG ($msg)\n";
    print STDERR "CURRENT MSG (".$self->log_message.")\n";

    $self->set_log_message($msg) if defined $msg;
    my $new_msg = $self->log_message;

    print STDERR "NEW MSG (".$new_msg.")\n";
    use Data::Dumper;
    print STDERR "DUMPED NEW MSG:".Dumper $new_msg;

    return $self->client_obj->commit(@args);
}

sub set_log_message {
    my ($self, $msg) = @_;
    $self->_set_log_message($msg);
}

sub log_message_callback {
    my $self = shift;

    my $log_msg = $self->log_message;

    use Data::Dumper;
    print STDERR "0 RETURNING (".$self->log_message.")\n";
    print STDERR "1 RETURNING ($log_msg)\n";
    print STDERR "LOG DUMP1:".Dumper $log_msg;
    print STDERR "LOG DUMP2:".Dumper $self;

    $_[0] = \$log_msg;

    $self->_clear_log_message;
}
[download]

And the corresponding output (also stripped down to important bits):

COMMIT CALLED WITH MSG (Committing new plist file revisions.)
CURRENT MSG ()
NEW MSG (Committing new plist file revisions.)
DUMPED NEW MSG:$VAR1 = 'Committing new plist file revisions.';
0 RETURNING (Committing new plist file revisions.)
1 RETURNING (*SVN::Handle::Committing new plist file revisions.)
LOG DUMP1:$VAR1 = *{'SVN::Handle::Committing new plist file revisions.
+'};
LOG DUMP2:$VAR1 = bless( {
                 'client_obj' => bless( {
                                          'ctx' => bless( do{\(my $o =
+ 30042304)}, '_p_svn_client_ctx_t' ),
                                          'auth_provider_callbacks' =>
+ [
                                                                      
+   \sub { "DUMMY" }
                                                                      
+ ],
                                          'pool' => bless( do{\(my $o 
+= bless( do{\(my $o = 187060184)}, '_p_apr_pool_t' ))}, 'SVN::Pool' )
+,
                                          'log_msg_callback' => \sub {
+ "DUMMY" }
                                        }, 'SVN::Client' ),
                 'log_message' => 'Committing new plist file revisions
+.',
                 'base_url' => 'https://subversion.jf.intel.com/iag/mg
+d/prmd/mtd/tpt/Rapttr/',
                 'repo_name' => 'rapttr_svn'
               }, 'SVN::Handle::RapTTR' );
[download]

Apologies for the messy multi-line output (Is there a better way to format that?). The commit is failing with this error:

Invalid value in log_msg reference, must be undef or a string at /nfs/pdx/disks/nehalem.pde.077/perl/5.12.2/lib64/site_perl/x86_64-linux/SVN/Client.pm line 927.

This is clearly because of the problem shown by the debug output lines here:

    my $log_msg = $self->log_message;
    print STDERR "0 RETURNING (".$self->log_message.")\n";
    print STDERR "1 RETURNING ($log_msg)\n";

# and output
0 RETURNING (Committing new plist file revisions.)
1 RETURNING (*SVN::Handle::Committing new plist file revisions.)
[download]

What I can't figure out is what is being dumped from $log_msg there. It behaves as a string when printed directly through the $self->log_message accessor. However, when I assign the return of that accessor to $log_msg, then print $log_msg I get that stringified...typeglob? The output from the dumped $self object clearly shows the log_message field having the correct value assigned to it, so this seems to be a case of a problem with the Moose accessor somehow.

I can't seem to get this to occur with a focused test case, so it must be related to other code somehow. But I follow up setting the log message with the commit directly, and the log_message value is dumped with the correct string value immediately prior to the commit. It's only inside the log_message_callback method where the problem shows up...which is called from the SVN::Client internals.

Any insights for me on this one? In any case, if you made it this far I genuinely appreciate your time :)

UPDATE: I've found the code works fine as long as I remove this:

$self->_clear_log_message;

from the log_message_callback method. Even with that line, it works the first time until that clear occurs. Am I improperly declaring/using the clearer method?