Testing wp_update_post and post_status transitions

gistfile1.php

<?php

if($_GET)
    test_content_date_edit();

function test_content_date_edit() {
        
        $newpostdata = array(
            'post_title' => 'test_post',
            'post_content' => 'test_content' );

        /**
         * These are the only bits being altered for the tests.
         * $post_id is only used when editing
         */
        
        $operation = 'edit';
        $post_date = strtotime( "yesterday" );
        $post_id = 40;
        
        /*
         * Simply check if the desired post is past/current or future, to decide
         * the new post_status
         */
        
        if ( $post_date < strtotime( "tomorrow" ) ) {
            $status = 'publish';    
            $newpostdata['post_status'] = $status;
            $newpostdata['post_date'] = date( 'Y-m-d H:i:s', $post_date );
            $msg .= 'publish';
        } elseif ( $post_date > strtotime( 'today' ) ) {
            $status = 'future';    
            $newpostdata['post_status'] = $status;
            $newpostdata['post_date'] = date( 'Y-m-d H:i:s', $post_date );
            $msg .= 'future';
        }
        
        /*
         * Test if we're including or editing and apply $post_id when needed.
         */
        
        if ( 'include' == $operation ) {
            $err = wp_insert_post($newpostdata, true);
            $msg .= ' include';
        } elseif ( 'edit' == $operation ) {
            $newpostdata['ID'] = $post_id;
            $err = wp_update_post( $newpostdata );
            $msg .= ' edit';
        }
            
    $msg = array('postid' => $err, 'resp' => $msg);
    var_dump($msg);
    return $msg;
}
?>