Blech. That is really the sort of code that makes perl's bad reputation...
So what do we have ? here's my explanation : the enclosing "[]" force an anonymous array context. Inside we have 2 array elements :

scalar => [+{ -type => 'File::stat' }, qw/ name /],
new    => 'new',
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The last one ( new => 'new') is clear enough. The first one is trickier : scalar is the hash key; let's analyse the content :

[+{ -type => 'File::stat' }, qw/ name /]
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the enclosing square braces once again force an anonymous array. Inside there are two elements :

+{ -type => 'File::stat' },
qw/ name /
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, the + force the following curly brace {} to be interpreted as an hash element and not a code block. so that's simply an anonymous hash entry.
"qw/name/" is just useless here because there's only one word...
Finally that's not very complex, just extremely obfuscated...
Here's what Data::Dumper can tell us about this structure, finally :

$VAR1 = {
          'scalar' => [
                        {
                          '-type' => 'File::stat'
                        },
                        'name'
                      ],
          'new' => 'new'
        };
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It's way better, isn't it ?
update : I forgot to mention that this structure looks like a pseudo-hash.