Which test?

I only investigated the failing test, #5.

Note that the end time and duration of each span is the same.

That could indicate a problem with test #2 or the possibility for confusion in reading the code for test #2.

There's no problem with test #2 because the docs clearly show one should use before instead of end if you want test #2 to be consistent with test #5.

---

Fixed test:

use strict;
use warnings;
use DateTime;
use DateTime::Span;
use Test::More tests => 6;

my $dt1 = DateTime->new(
    day  =>  1, month  => 1, year   => 2011,
    hour => 12, minute => 0, second =>    0,
);

my $dt2 = $dt1->clone->add( hours => 1 );
my $duration = DateTime::Duration->new( hours => 1 );

{
    my $span = DateTime::Span->from_datetimes(
        start  => $dt1,
        before => $dt2,
    );

    diag $span->start->datetime();
    diag $span->end->datetime();

    ok( $span->intersects( $dt1 ),
        'Span intersects $dt1'
    );

    ok( !$span->intersects( $dt2 ),
        'Span doesn\'t intersects $dt2'
    );

    is( DateTime::Duration->compare( $span->duration, $duration ), 0,
        'Duration is 1 hour'
    );
}

{
    my $span = DateTime::Span->from_datetime_and_duration(
        start    => $dt1,
        duration => $duration,
    );

    diag $span->start->datetime();
    diag $span->end->datetime();

    ok( $span->intersects( $dt1 ),
        'Span intersects $dt1'
    );

    ok( !$span->intersects( $dt2 ),
        'Span doesn\'t intersects $dt2'
    );

    is( DateTime::Duration->compare( $span->duration, $duration ), 0,
        'Duration is 1 hour'
    );
}

1;
[download]

1..6
# 2011-01-01T12:00:00
# 2011-01-01T13:00:00
ok 1 - Span intersects $dt1
ok 2 - Span doesn't intersects $dt2
ok 3 - Duration is 1 hour
# 2011-01-01T12:00:00
# 2011-01-01T13:00:00
ok 4 - Span intersects $dt1
ok 5 - Span doesn't intersects $dt2
ok 6 - Duration is 1 hour
[download]

PS - I used ok instead of is because intersects is documented to return a boolean, not zero or one.