Move and improve the subclass validation logic into a new helper module

[perl/modules/Test-Valgrind.git] / lib / Test / Valgrind / Util.pm

diff --git a/lib/Test/Valgrind/Util.pm b/lib/Test/Valgrind/Util.pm
new file mode 100644 (file)
index 0000000..441ce69
--- /dev/null
+++ b/lib/Test/Valgrind/Util.pm
@@ -0,0 +1,88 @@
+package Test::Valgrind::Util;
+
+use strict;
+use warnings;
+
+=head1 NAME
+
+Test::Valgrind::Util - Utility routines for Test::Valgrind.
+
+=head1 VERSION
+
+Version 1.15
+
+=cut
+
+our $VERSION = '1.15';
+
+=head1 DESCRIPTION
+
+This module contains some helpers used by Test::Valgrind.
+It is not really designed to be used anywhere else.
+
+=head1 FUNCTIONS
+
+=head2 C<validate_subclass>
+
+    my ($validated_type, $error_msg) = validate_subclass($type);
+
+Try to interpret C<$type> as a subclass of the caller package, and load it if its C<@ISA> is empty.
+Returns the validated type, or C<undef> and the relevant error message.
+
+=cut
+
+sub validate_subclass {
+ my ($type) = @_;
+
+ my $base = (caller 0)[0];
+
+ $type =~ s/[^A-Za-z0-9_:]//g;
+ $type =  "${base}::$type" if $type !~ /::/;
+
+ my $stash = do { no strict 'refs'; \%{"${type}::"} };
+ my $ISA   = ($stash && $stash->{ISA}) ? *{$stash->{ISA}}{ARRAY} : undef;
+
+ unless ($ISA and @$ISA >= 1) {
+  local $@;
+  eval "require $type; 1" or return (undef, "Could not load subclass: $@");
+ }
+
+ return (undef, "$type is not a subclass of $base") unless $type->isa($base);
+
+ return $type;
+}
+
+=head1 EXPORT
+
+This module does not export anything.
+
+=head1 SEE ALSO
+
+L<Test::Valgrind>.
+
+=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-test-valgrind at rt.cpan.org>, or through the web interface at L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Test-Valgrind>.
+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 Test::Valgrind::Component
+
+=head1 COPYRIGHT & LICENSE
+
+Copyright 2015 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 Test::Valgrind::Util