Question

I am trying to set a custom class to an Iterator through the setInfoClass method:

Use this method to set a custom class which will be used when getFileInfo and getPathInfo are called. The class name passed to this method must be derived from SplFileInfo.

My class is like this (simplified example):

class MyFileInfo extends SplFileInfo
{
    public $props = array(
        'foo' => '1',
        'bar' => '2'
    );
}

The iterator code is this:

$rit = new RecursiveIteratorIterator(
           new RecursiveDirectoryIterator('/some/file/path/'),
           RecursiveIteratorIterator::SELF_FIRST);

Since RecursiveDirectoryIterator is by inheritance through DirectoryIterator also an SplFileInfo object, it provides the setInfoClass method. It’s not listed in the manual, but reflection shows it’s there:

shell$ php --rc RecursiveDirectoryIterator
// ...
Method [ <internal:SPL, inherits SplFileInfo> public method setInfoClass ] {  
  - Parameters [1] {
    Parameter #0 [ <optional> $class_name ]
  }
}

All good up to here, but when iterating over the directory with

$rit->getInnerIterator()->setInfoClass('MyFileInfo');
foreach($rit as $file) {
    var_dump( $file );
}

I get the following weird result

object(MyFileInfo)#4 (3) {
  ["props"]=>UNKNOWN:0
  ["pathName":"SplFileInfo":private]=>string(49) "/some/file/path/someFile.txt"
  ["fileName":"SplFileInfo":private]=>string(25) "someFile.txt"
}

So while MyFileInfo is picked up, I cannot access it’s properties. If I add custom methods, I can invoke them fine, but any properties are UNKNOWN.

If I don’t set the info class to the iterator, but to the SplFileInfo object (like shown in the example in the manual), it will give the same UNKNOWN result:

foreach($rit as $file) {
    // $file is a SplFileInfo instance
    $file->setInfoClass('MyFileInfo');
    var_dump( $file->getFileInfo() );
}

However, it will work when I do

foreach($rit as $file) {
    $file = new MyFileInfo($file);
    var_dump( $file );
}

Unfortunately, the code I want to use this in is somewhat more complicated and stacks some more iterators. Creating the MyFileInfo class like this is not an option.

So, does anyone know how to get this working or why PHP behaves this weird?

Thanks.

Answer 1

Can’t tell you exactly why but it works with

class MyFileInfo extends SplFileInfo
{
  public $props;

  public function __construct($filename) {
    $this->props = array(
      'foo' => '1',
      'bar' => '2'
    );

    parent::__construct($filename);
  }
}