Debugging image uploads with wp_generate_attachment_metadata

[Fleuv]

Because of the if statement declared in image.php on line 181 (https://core.trac.wordpress.org/browser/tags/4.9/src/wp-admin/includes/image.php#L181) it seems impossible to retrieve the error message, what is supplied by the wp_upload_bits() function.

Please return this message or implement a new function what verifies what the error messages are trying to inform the user about.

[kirasong]

Hi @Fleuv! Thanks much for this ticket.

I completely agree with you that there should be a better way to troubleshoot image manipulation failures/errors.

Going to mark this as Future Release because I agree it's important. Open for suggestions/patches from anyone as to the best way to surface this information.