Bug #16125 for Test-Unit: Assertions on hash references do not work

Fri Nov 25 14:50:52 2005 GUIDO [...] cpan.org - Ticket created

Subject:

Assertions on hash references do not work

The following code in a test: my $hashref = {}; $self->assert ($hashref); will fail with: can't call method "can" on unblessed reference. Variant: my $scalarref = \"foobar"; $self->assert ($scalarref); will fail with: Don't know how to normalize SCALAR(0x85dd580) (ref SCALAR) The first case is a bug, the second IMHO a nuisance. The "normalization" is a surprising feature, and not really helpful. Besides, the documentation seems to divert from the implementation in Test::Unit::Assert. My expectation was that assert() would succeed if its first argument evaluates to a truth value. It's Perl after all. Regards, Guido

Sun Nov 27 08:44:45 2005 mca1001 [...] users.sourceforge.net - Given to MCAST

Sun Nov 27 08:44:45 2005 mca1001 [...] users.sourceforge.net - Status changed from 'new' to 'open'

Sun Nov 27 08:44:46 2005 mca1001 [...] users.sourceforge.net - Correspondence added

Subject:

assert() is heavily overloaded

The T:U:Assert->assert method is overloaded to do various things depending on the first argument. The behaviour on HASH ref isn't useful ... and the documentation doesn't explain what's going on. The fundamental problem with the assert method is that we don't get the benefit of prototypes to assist with scalar vs. list context, and we don't get language support for spiffy overloading so it's done by hand - in this case with no check for blessedness. I would like to give this area some serious attention, but that will have to be "later". For now, I believe the best solution is to mark the assert method with "here be dragon". It has bitten people various ways, so for now it may be better to write exactly what you mean, $self->fail("wanted true") if !$hashref; $self->fail("wanted plain hash") if ref($hashref) ne "HASH"; For completeness, I mention the worst problem $self->assert($str =~ /regexp/, "did not match"); # WRONG $self->assert(scalar $str =~ /regexp/, "did not match"); # works ok $self->fail("did not match") unless $str =~ /regexp/; # works ok $self->assert(qr/regexp/, $str, "did not match"); # official version and the complaint about parameters being the wrong way around, http://sourceforge.net/tracker/index.php?func=detail&aid=407833&group_id=2653&atid=102653 Sourceforge bug #407833