Debug Data: Encode section ordering in debug info.

During a refactor to modularize the debug data class, it came up that the ordering of the sections inside of the returned debug info is relevant to existing UIs, as they iterate the array, which happens in insertion order.

This patch presets each section at the start to ensure that the ordering remains consistent even as code within the method is rearranged. As the mini-project progresses, this assignment will be the final place all the sections are referenced.

Developed in WordPress#7289
Discussed in https://core.trac.wordpress.org/ticket/61648

Props apermo, dmsnell, sergeybiryukov.
See #61648.


git-svn-id: https://develop.svn.wordpress.org/trunk@58996 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/class-wp-debug-data.php

@@ -61,8 +61,35 @@ public static function debug_data() {
 			}
 		}
 
-		// Set up the array that holds all debug information.
-		$info = array();
+		/*
+		 * Set up the array that holds all debug information.
+		 *
+		 * When iterating through the debug data, the ordering of the sections
+		 * occurs in insertion-order of the assignments into this array. Setting
+		 * up empty values here preserves that specific ordering so it doesn't
+		 * depend on when inside this method each section is otherwise assigned.
+		 *
+		 * When all sections have been modularized, this will be the final single
+		 * assignment of the sections before filtering and none will be empty.
+		 *
+		 * @ticket 61648
+		 */
+		$info = array(
+			'wp-core'             => array(),
+			'wp-paths-sizes'      => array(),
+			'wp-dropins'          => array(),
+			'wp-active-theme'     => array(),
+			'wp-parent-theme'     => array(),
+			'wp-themes-inactive'  => array(),
+			'wp-mu-plugins'       => array(),
+			'wp-plugins-active'   => array(),
+			'wp-plugins-inactive' => array(),
+			'wp-media'            => array(),
+			'wp-server'           => array(),
+			'wp-database'         => self::get_wp_database(),
+			'wp-constants'        => self::get_wp_constants(),
+			'wp-filesystem'       => self::get_wp_filesystem(),
+		);
 
 		$info['wp-core'] = array(
 			'label'  => __( 'WordPress' ),
@@ -1154,10 +1181,6 @@ public static function debug_data() {
 			);
 		}
 
-		$info['wp-constants']  = self::get_wp_constants();
-		$info['wp-database']   = self::get_wp_database();
-		$info['wp-filesystem'] = self::get_wp_filesystem();
-
 		/**
 		 * Filters the debug information shown on the Tools -> Site Health -> Info screen.
 		 *