Merged in feature/from-pantheon (pull request #16)

code from pantheon

* code from pantheon

wp/wp-content/mu-plugins/loader.php

@@ -0,0 +1,76 @@
+<?php
+/**
+ * Plugin Name: Pantheon MU Plugin Loader
+ * Description: Loads the MU plugins required to run the site
+ * Author: Pantheon Systems
+ * Author URI: https://pantheon.io
+ * Version: 1.0
+ */
+
+if ( defined( 'WP_INSTALLING' ) && WP_INSTALLING ) {
+	return;
+}
+
+// Add mu-plugins here.
+$pantheon_mu_plugins = [
+	'pantheon-mu-plugin/pantheon.php',
+];
+
+foreach ( $pantheon_mu_plugins as $file ) {
+	require_once WPMU_PLUGIN_DIR . '/' . $file;
+}
+unset( $file );
+
+add_action( 'pre_current_active_plugins', function () use ( $pantheon_mu_plugins ) {
+	global $plugins, $wp_list_table;
+
+	// Add our own mu-plugins to the page.
+	foreach ( $pantheon_mu_plugins as $plugin_file ) {
+		// Do not apply markup/translate as it'll be cached.
+		$plugin_data = get_plugin_data( WPMU_PLUGIN_DIR . "/$plugin_file", false, false );
+
+		if ( empty( $plugin_data['Name'] ) ) {
+			$plugin_data['Name'] = $plugin_file;
+		}
+
+		$plugins['mustuse'][ $plugin_file ] = $plugin_data;
+	}
+
+	// Recount totals.
+	$GLOBALS['totals']['mustuse'] = count( $plugins['mustuse'] );
+
+	// Only apply the rest if we're actually looking at the page.
+	if ( $GLOBALS['status'] !== 'mustuse' ) {
+		return;
+	}
+
+	// Reset the list table's data.
+	$wp_list_table->items = $plugins['mustuse'];
+	foreach ( $wp_list_table->items as $plugin_file => $plugin_data ) {
+		$wp_list_table->items[ $plugin_file ] = _get_plugin_data_markup_translate( $plugin_file, $plugin_data, false, true );
+	}
+
+	$total_this_page = $GLOBALS['totals']['mustuse'];
+
+	if ( $GLOBALS['orderby'] ) {
+		uasort( $wp_list_table->items, [ $wp_list_table, '_order_callback' ] );
+	}
+
+	// Force showing all plugins.
+	// See https://core.trac.wordpress.org/ticket/27110.
+	$plugins_per_page = $total_this_page;
+
+	$wp_list_table->set_pagination_args( [
+		'total_items' => $total_this_page,
+		'per_page'    => $plugins_per_page,
+	] );
+});
+
+add_filter( 'network_admin_plugin_action_links', function ( $actions, $plugin_file, $plugin_data, $context ) use ( $pantheon_mu_plugins ) {
+	if ( $context !== 'mustuse' || ! in_array( $plugin_file, $pantheon_mu_plugins, true ) ) {
+		return $actions;
+	}
+
+	$actions[] = sprintf( '<span style="color:#333">File: <code>%s</code></span>', $plugin_file );
+	return $actions;
+}, 10, 4 );