Debug on fail

Changes

@@ -1,5 +1,7 @@
 {{$NEXT}}
 
+    - Add Test2::Plugin::DebugOnFail
+
 0.000153  2023-04-27 15:27:32-07:00 America/Los_Angeles
 
     - Fix broken call to plugins

lib/Test2/Plugin/DebugOnFail.pm

@@ -0,0 +1,84 @@
+package Test2::Plugin::DebugOnFail;
+use strict;
+use warnings;
+
+our $VERSION = '0.000154';
+
+use Test2::API qw{
+    test2_add_callback_post_load
+    test2_stack
+};
+
+sub import {
+    my $class = shift;
+
+    test2_add_callback_post_load(sub {
+        my $hub = test2_stack()->top;
+
+        $hub->pre_filter(
+            sub {
+                my ($hub, $event) = @_;
+
+                if ($event->causes_fail) {
+                    warn "Test failure detected, stopping debugger...\n";
+                    $DB::single = 1;
+                }
+
+                return $event;
+            },
+            inherit => 1,
+        );
+    });
+}
+
+1;
+
+__END__
+
+=pod
+
+=encoding UTF-8
+
+=head1 NAME
+
+Test2::Plugin::DebugOnFail - Set "$DB::single = 1" on test failure.
+
+=head1 DESCRIPTION
+
+This will set C<$DB::single = 1> on any failure in the test suite.
+
+=head1 SYNOPSIS
+
+    use Test2::Plugin::DebugOnFail;
+
+=head1 SOURCE
+
+The source code repository for Test2-Suite can be found at
+F<https://github.com/Test-More/Test2-Suite/>.
+
+=head1 MAINTAINERS
+
+=over 4
+
+=item Chad Granum E<lt>[email protected]<gt>
+
+=back
+
+=head1 AUTHORS
+
+=over 4
+
+=item Chad Granum E<lt>[email protected]<gt>
+
+=back
+
+=head1 COPYRIGHT
+
+Copyright 2018 Chad Granum E<lt>[email protected]<gt>.
+
+This program is free software; you can redistribute it and/or
+modify it under the same terms as Perl itself.
+
+See F<http://dev.perl.org/licenses/>
+
+=cut

t/modules/Plugin/DebugOnFail.t

@@ -0,0 +1,23 @@
+use Test2::V0;
+use Test2::API qw/intercept/;
+
+my ($start, $second, $third);
+my $events = intercept {
+    require Test2::Plugin::DebugOnFail;
+    Test2::Plugin::DebugOnFail->import;
+
+    my $warn;
+    local $SIG{__WARN__} = sub { ($warn) = @_ };
+
+    $start = $warn;
+    ok(1);
+    $second = $warn;
+    ok(0);
+    $third = $warn;
+};
+
+is($start, undef, "Not set initially");
+is($second, undef, "Not set after pass");
+is($third, "Test failure detected, stopping debugger...\n", "Is set after pass");
+
+done_testing;