I was trying to work out the difference between this and getBasename (http://php.net/manual/splfileinfo.getbasename.php) and the only difference I could really see was a special case of a file in the filesystem root with the root specified:

<?php
function getInfo($reference)
{
    $file = new SplFileInfo($reference);

    var_dump($file->getFilename());
    var_dump($file->getBasename());
}

$test = [
    '/path/to/file.txt',
    '/path/to/file',
    '/path/to/',
    'path/to/file.txt',
    'path/to/file',
    'file.txt',
    '/file.txt',
    '/file',
];

foreach ($test as $file) {
    getInfo($file);
}

// will return:
/*
string(8) "file.txt"
string(8) "file.txt"

string(4) "file"
string(4) "file"

string(2) "to"
string(2) "to"

string(8) "file.txt"
string(8) "file.txt"

string(4) "file"
string(4) "file"

string(8) "file.txt"
string(8) "file.txt"

string(9) "/file.txt" // see how getFilename includes the '/'
string(8) "file.txt"  // but getBasename doesn't

string(5) "/file"     // ditto getFilename
string(4) "file"      // ditto getBasename
*/

?>

It should be mentioned that the function returns the name of the directory if "filename" is of type "directory". Hence

<?php
$info = new SplFileInfo('/path/to/');
var_dump($info->getFilename());
?>

should return "to"

The function name is kind of misleading here and I am glad to have it tried.

// Careful, output is different for `filename` vs `getFilename`. Inconsistent behaviour.

$path = 'test.txt';

$pathInfo = pathinfo($path);
echo '<pre>';
print_r($pathInfo);

echo '<br>';
echo '***************';

$splFileInfo = new SplFileInfo($path);
echo '<br>';
echo $splFileInfo->getBasename();

echo '<br>';
echo $splFileInfo->getFilename();