inconsistent icon_dir/icon_dirs use in wp_mime_type_icon and wp_get_attachment_image_src

[dglingren]

/wp-includes/post.php function wp_mime_type_icon allows for multiple icon image directories by applying the "icon_dirs" filter:

if ( !is_array($icon_files) ) {
    $icon_dir = apply_filters( 'icon_dir', ABSPATH . WPINC . '/images/crystal' );
    $icon_dir_uri = apply_filters( 'icon_dir_uri', includes_url('images/crystal') );
    $dirs = apply_filters( 'icon_dirs', array($icon_dir => $icon_dir_uri) );
    $icon_files = array();
    while ( $dirs ) {
    ...

However, /wp-includes/media.php function wp_get_attachment_image_src does not apply the "icon_dirs" filter:

if ( $icon && $src = wp_mime_type_icon($attachment_id) ) {
    $icon_dir = apply_filters( 'icon_dir', ABSPATH . WPINC . '/images/crystal' );
    $src_file = $icon_dir . '/' . wp_basename($src);
    @list($width, $height) = getimagesize($src_file);
}

The base filename is always combined with the default Wordress directory path and passed to getimagesize. This means that any additional directories will never be passed to getimagesize(), and an incorrect size or no size at all will be used for any icon image files not sourced from the WordPress default directory.

[SergeyBiryukov]

Related: #20205

[joostdekeijzer]

method now uses 'icon_files' cache created by wp_mime_type_icon

[joostdekeijzer]

Attached patch for this issue and fixed ​brace style

[jorbin]

I'm not quite sure how to reproduce this based on the description. Some sample code and/or instructions would help here.

[dglingren]

Thank you for looking into this issue. To reproduce the problem:

1. Create a directory and put an icon in it, e.g.,

/wp-content/plugins/media-library-assistant/images/crystal/pdf.png'

2. Hook the 'ext2type' filter and add an association from a file type to the icon, e.g.,

array( 'pdf' => array ( 0 => 'pdf', )

3. Hook the 'icon_dirs' filter and add the directory and url to the array, e.g.,

function mla_icon_dirs_filter( $path_uri_array ) {
$path_uri_array [ MLA_PLUGIN_PATH . 'images/crystal' ] = MLA_PLUGIN_URL . 'images/crystal';
return $path_uri_array;
}

wp_mime_type_icon() will find pdf.png in the added directory, but wp_get_attachment_image_src() will discard the path and look for the file in the WordPress default directory; " $src_file = $icon_dir . '/' . wp_basename($src); ".

I regret that the initial description was unclear, and if you need anything else I am happy to expand on the above.

[joostdekeijzer]

@jorbin alternatively you could install and enable ​https://wordpress.org/plugins/oembed-in-library/

Add and Vimeo or Youtube video (Media > oEmbed). Then go to the Media library in list mode. You should get an icon based on the mime type (Vimeo or Youtube logo) but you get an empty space (no icon).