Undefinded Variable in Media-Modal

[arkonisus]

If you try to place some images and open the media-modal you will get the following error if there are also PDFs or other filetypes than 'image' in the list:

PHP Notice:  Undefined variable: base_url in ... /wp-includes/media.php on line 3204

The problem is that the variable was declared inside an IF-clause some lines before (line 3172ff.):

} elseif ( isset( $meta['sizes'][ $size ] ) ) {
    if ( ! isset( $base_url ) )
        $base_url = str_replace( wp_basename( $attachment_url ), '', $attachment_url );

[Fencer04]

So if I am editing a page and I click Add Media and the list has a PDF in it you are seeing the error? I just want to make sure I'm replicating it correctly because I have an image, a PDF and an mp3 and am not getting the error with the steps I mentioned above.

[arkonisus]

Sorry, it is a little bit strange ... I installed a blank WP and yes, it is all fine - no error! So i deleted all the plugins and theme data, posts and media in the faulty installation but the error was still present. OK, my last attempt was to reset the whole database ... and now all runs fine! It seems the reason was a buggy option in my database. But:

During my certain attempts i found out that it shows the default PDF-thumbnail in the media-modal and so i got the error. In the 'normal' media-view (upload.php) the thumbnail was correctly rendered and there was also no error message.

[Fencer04]

Ok, this doesn't appear to be an error in the standard code base. I will close it.

[arkonisus]

Replying to Fencer04:

Ok, this doesn't appear to be an error in the standard code base. I will close it.

Just after you closed this ticket i found out why this error appears ... :)
In my installation i set all image-sizes to '0' (settings->media) because i don't need any default thumbnails.

[joemcgill]

Replying to arkonisus:

In my installation i set all image-sizes to '0' (settings->media) because i don't need any default thumbnails.

This seems like a valid use case that WordPress should handle. The bug was introduced in [38949].

[Fencer04]

Interesting, I can't replicate this on my end but I agree that it is a valid use case.

[dd32]

Note; You'll need WP_DEBUG enabled to see PHP Notices.
That normally means we leave it for the next major release and don't do the .1, especially considering how edge case this is.

[dd32]

In 39612:

Media: Move a variable definition outside of conditionals to ensure it's always available.
This fixes cases where the URL to a PDF preview may be incorrectly calculated when no thumbnails were generated for the PDF (and avoids a PHP Notice at the same time).

Fixes #39250.

[dd32]

I never actually reproduced seeing a PHP Notice, but i did run into the side effects of it and reproduce the code paths.

Re-opening for 4.7.1, as it's a minor change and we've already modified the file, so no harm in including it.

Due to the complexities of testing it, I've not created a unit test for it, but if someone would like to attempt one, please feel free to.

[dd32]

In 39654:

Media: Move a variable definition outside of conditionals to ensure it's always available.
This fixes cases where the URL to a PDF preview may be incorrectly calculated when no thumbnails were generated for the PDF (and avoids a PHP Notice at the same time).

Merges [39612] to the 4.7 branch.
Fixes #39250.