Filter to allow insertion of messages onto the post edit form

[simonwheatley]

Currently it's not easily possible to insert a message onto the edit form; for example a plugin might check a post on publication, determine it's unsuitable in some way and need to return the user to their post with a message explaining what's happened.

The attached patch adds a filter hook to allow plugin authors to manipulate the message being displayed on edit_form_advanced.php. Example plugin code shown below:

// Fictional example, for simplicity...
// This function triggered by a $_GET param. The $_GET
// param is added if the profanity filter detects rudeness.
function em_filter_display_message( $display_message )
{
	// Should we display a message?
	$em_message = (bool) @ $_GET['em_message'];
	if ( ! $em_message ) return $display_message;
	// OK. Let's display one...
	return 'Hello. This is WordPress speaking... less profanity in your posts, please.';
}

// Our message
add_filter( 'edit_form_advanced_message', 'em_filter_display_message' );

Patch adding filter to manipulate user message edit_form_advanced.php

I think an action would be better here to allow a plugin to just output some html instead.

Move to 2.8 for now as we are feature frozen

Punting due to feature freeze. Reconsider with next release.

see admin_notices