[PATCH] t/filter_base: relax Regexp class match with ->isa

[Eric Wong <e@80x24.org>]

It would be nice to support alternative Regexp engines such
as re::engine::PCRE2 in the future.  The exact ref() name
can't match, however ->isa() works with re::engine::PCRE2.
So future-proof our code for potential changes in case PCRE2
becomes usable.
---
 Unfortunately, attempting to use re::engine::PCRE2 with
 PublicInbox::Eml shows t/eml.t failures from regexps made
 by re_memo as well as the MIME boundary splitting with
 Perl 5.32, and probably other things...

 t/filter_base.t | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/t/filter_base.t b/t/filter_base.t
index 2646321a..3a0dbf8b 100644
--- a/t/filter_base.t
+++ b/t/filter_base.t
@@ -10,7 +10,7 @@ use_ok 'PublicInbox::Filter::Base';
 	my $f = PublicInbox::Filter::Base->new;
 	ok($f, 'created stock object');
 	ok(defined $f->{reject_suffix}, 'rejected suffix redefined');
-	is(ref($f->{reject_suffix}), 'Regexp', 'reject_suffix should be a RE');
+	ok $f->{reject_suffix}->isa('Regexp'), 'reject_suffix should be a RE';
 }
 
 {