On Tue, Jun 30, 2009 at 6:17 PM, Ovid<publiustemp-perl...@yahoo.com> wrote:
>
> Part of the problem with have with 'Test::More' and friends is that there's
> not an easy way to attach diagnostics to any test. This is largely because
> the interface is set in stone. So I was thinking about a rewritten test
> interface which allows something like this (this code actually works, by the
> way):
>
> use Test::Fluent 'no_plan';
>
> my ( $have, $want ) = ( 1, 1 );
> have $have, want $want, reason 'Some test name';
> have [ 3, 4 ], want [ 4, 5 ], reason 'cuz I said so'; # fails
> true 3, reason '3 had better be true';
> false 3, reason '3 had better still better be true'; # fails
>
>
> At the end of each of those, you could append a 'diagnostics' tag which is
> required to take a hashref:
>
> my $armageddon = $world->destruction;
> false $armaggedon,
> reason "World->destruction must never return true",
> diagnostic { world => $world };
>
> I don't know that this is a brilliant interface, but just playing around with
> it works (the have/want pair automatically falls back to Test::Differences if
> $have or $want is a reference).
>
> It's a lot more explicit that Test::More and friends. That means it's a lot
> more verbose. However, it's something which could be played with.
>
> Is this a bad idea? Are there other suggestions people want? If we had a
> dot operator, it would be clean to write this:
>
> have($have).want($want).reason($some_reason);
>
> But we don't, so we'd have to fall back on the ugly:
>
> have($have)->want($want)->reason($some_reason);
>
> Though I could easily overload the dot operator to get the first syntax.
>
> Or if we needed delayed evaluation for some reason:
>
> have { $have }, want { $want }, reason $some_reason);
>
> That's also ugly and requires the (&) prototype (and friends).
>
> Thoughts? Am I totally smoking crack here? If there's a clean way to
> shoehorn diagnostics on the Test::More-style interface, I guess that would be
> ok.
>
> Cheers,
> Ovid
> --
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>
>
At the hackathon Schwern and I had a go at implementing the ugly ->
type interface for Test::Builder2 based on an idea from a PDX.pm
meeting.
The idea being that it would work something like this,
ok($func('a'), 'some test')->diag('some cheap diagnostics');
or for delayed diagnostics,
{
my $result = ok $func('a'), 'A test';
if(!$result) {
$result->diag("expensive diagnostics we'd rather not run");
}
}
The idea being that these result objects would then be usable by
modules like Test::More and you would be able to easily attach
diagnostics in the right place.
Note that the block in the second example is a necessary evil for the
delayed diagnostics because of the way we make sure we don't produce
the output before we know what diagnostics come with the test.
I did have a go at writing this up at
http://colinnewell.wordpress.com/2009/03/31/perl-qa-hackathon-testbuilder2/.
Colin.
