Introduce a scope guard object

diff --git a/MANIFEST b/MANIFEST
index 4e8302276cc14ae66a6fa09215d5936c0686b4d4..e3e62238955b52e18b4f8f99b6069fc3a8240def 100644 (file)
--- a/MANIFEST
+++ b/MANIFEST
@@ -5,6 +5,7 @@ Makefile.PL
 README
 lib/CPANPLUS/Dist/Gentoo.pm
 lib/CPANPLUS/Dist/Gentoo/Atom.pm
+lib/CPANPLUS/Dist/Gentoo/Guard.pm
 lib/CPANPLUS/Dist/Gentoo/Maps.pm
 lib/CPANPLUS/Dist/Gentoo/Version.pm
 samples/g-cpanp
@@ -17,6 +18,7 @@ t/20-version.t
 t/30-atom-new.t
 t/31-atom-cmp.t
 t/32-atom-and.t
+t/40-guard.t
 t/91-pod.t
 t/92-pod-coverage.t
 t/95-portability-files.t

diff --git a/lib/CPANPLUS/Dist/Gentoo/Guard.pm b/lib/CPANPLUS/Dist/Gentoo/Guard.pm
new file mode 100644 (file)
index 0000000..87dbaa8
--- /dev/null
+++ b/lib/CPANPLUS/Dist/Gentoo/Guard.pm
@@ -0,0 +1,92 @@
+package CPANPLUS::Dist::Gentoo::Guard;
+
+use strict;
+use warnings;
+
+=head1 NAME
+
+CPANPLUS::Dist::Gentoo::Guard - Scope guard object.
+
+=head1 VERSION
+
+Version 0.09
+
+=cut
+
+our $VERSION = '0.09';
+
+=head1 DESCRIPTION
+
+This is a scope guard object helper for L<CPANPLUS::Dist::Gentoo>.
+
+=head1 METHODS
+
+=head2 C<new $coderef>
+
+Creates a new L<CPANPLUS::Dist::Gentoo::Guard> object that will call C<$coderef> when destroyed.
+
+=cut
+
+sub new {
+ my ($class, $code) = @_;
+ $class = ref($class) || $class;
+
+ bless {
+  code  => $code,
+  armed => 1,
+ }, $class;
+}
+
+=head2 C<unarm>
+
+Tells the object not to call the stored callback on destruction.
+
+=cut
+
+sub unarm { $_[0]->{armed} = 0 }
+
+=head2 C<DESTROY>
+
+Calls the stored callback if the guard object is still armed.
+
+=cut
+
+sub DESTROY {
+ my ($self) = @_;
+
+ $self->{code}->() if $self->{armed};
+ $self->unarm;
+
+ return;
+}
+
+=head1 SEE ALSO
+
+L<CPANPLUS::Dist::Gentoo>.
+
+=head1 AUTHOR
+
+Vincent Pit, C<< <perl at profvince.com> >>, L<http://www.profvince.com>.
+
+You can contact me by mail or on C<irc.perl.org> (vincent).
+
+=head1 BUGS
+
+Please report any bugs or feature requests to C<bug-cpanplus-dist-gentoo at rt.cpan.org>, or through the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=CPANPLUS-Dist-Gentoo>.
+I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.
+
+=head1 SUPPORT
+
+You can find documentation for this module with the perldoc command.
+
+    perldoc CPANPLUS::Dist::Gentoo
+
+=head1 COPYRIGHT & LICENSE
+
+Copyright 2009,2010 Vincent Pit, all rights reserved.
+
+This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
+
+=cut
+
+1; # End of CPANPLUS::Dist::Gentoo::Guard

diff --git a/t/40-guard.t b/t/40-guard.t
new file mode 100644 (file)
index 0000000..954deab
--- /dev/null
+++ b/t/40-guard.t
@@ -0,0 +1,36 @@
+#!perl -T
+
+use strict;
+use warnings;
+
+use Test::More tests => 9;
+
+use CPANPLUS::Dist::Gentoo::Guard;
+
+my $called = 0;
+my $hook = sub { $called++ };
+
+is $called, 0, 'not called yet';
+{
+ my $guard = CPANPLUS::Dist::Gentoo::Guard->new($hook);
+ is $called, 0, 'creating the guard doesn\'t call the hook';
+}
+is $called, 1, 'called at end of scope';
+
+$called = 0;
+is $called, 0, '$called reset';
+{
+ my $guard = CPANPLUS::Dist::Gentoo::Guard->new($hook);
+ $guard->unarm;
+ is $called, 0, 'unarming the guard doesn\'t call the hook';
+}
+is $called, 0, 'not called at end of scope';
+
+$called = 0;
+is $called, 0, '$called reset again';
+{
+ my $guard = CPANPLUS::Dist::Gentoo::Guard->new($hook);
+ $guard->DESTROY;
+ is $called, 1, 'called DESTROY explicitely';
+}
+is $called, 1, 'the hook was called only once';