_wp_page_template is getting 'stuck' to a page

[shawmutsteve]

Unmodified WP 3.4.1 / Ummodified TwentyEleven theme

Create a page (id=2). Manually add a postmeta entry for

post_id=2, 
meta_key = _wp_page_template, 
meta_value = pagefull.php

The page now opens with margin: 0 7.6%; (correct!)

Now try to change it back to default, either by removing the _wp_page_template postmeta record or by editing the page -> Page Attribute / Template. The page will not revert back to Default. It continually displays as Full Width, and a postmeta item telling post_id 2 to use _wp_page_template = pagefull.php is added.

​http://wp34.roveridx.com/?page_id=2

This behavior does not happen in 3.3.2.

[cbaldelomar]

This could be solved by changing the following line of code on line 659 in file 'wp-admin/includes/meta-boxes.php'

	if ( 'page' == $post->post_type && 0 != count( get_page_templates() ) ) {

to

	if ( 'page' == $post->post_type ) {

This would always cause a dropdown to be displayed in the Page Attributes Meta Box even if "Default Template" is the only page template option.

This could be a very frustrating experience for a new Wordpress user, who, after switching themes, will no longer be able to update their post_meta fields because their page template is "stuck" on some other themes page template.

Consider this bit of code in 'wp-includes/post.php'. The code will fail when checking for a valid page template, and never run the function, update_post_meta(); So plugins like Yoast SEO or any other using custom meta fields will not be able to save new inputs.

 	if ( !empty($page_template) && 'page' == $data['post_type'] ) {
		$post->page_template = $page_template;
		$page_templates = wp_get_theme()->get_page_templates();
		if ( 'default' != $page_template && ! isset( $page_templates[ $page_template ] ) ) {
			if ( $wp_error )
				return new WP_Error('invalid_page_template', __('The page template is invalid.'));
			else
				return 0;
		}
		update_post_meta($post_ID, '_wp_page_template',  $page_template);
	}

I hope this is helpful for someone and that this problem can get solved.

[wpdavis]

Thanks for the report. I can't reproduce this in later versions of WordPress — can you please upgrade to 3.7 and let update this ticket if you're still having that problem?

[wonderboymusic]

No longer stuck after [31020] - if you save the post after switching themes, it will revert to 'default' page template

[ocean90]

Duplicate of #25334.