Index: wp-admin/includes/class-wp-debug-data.php
===================================================================
--- wp-admin/includes/class-wp-debug-data.php	(revision 55892)
+++ wp-admin/includes/class-wp-debug-data.php	(working copy)
@@ -20,6 +20,23 @@
 		wp_update_themes();
 	}
 
+	/*
+	* Returns the value of a defined constant. If the constant is defined as empty, it will return "Defined as empty".
+	* If the constant is not defined, it will return "Undefined"
+	*/
+	private static function get_define_info( $constant_name ) {
+		// Check WP_ENVIRONMENT_TYPE.
+		if ( defined( $constant_name ) ) {
+			$value = constant( $constant_name );
+			if( !$value ) {
+				$value = __( 'Defined as empty' );
+			}
+		} else {
+			$value = __( 'Undefined' );
+		}
+		return $value;
+	}
+
 	/**
 	 * Static function for generating site debug data when required.
 	 *
@@ -236,13 +253,6 @@
 			$compress_css_debug = 'undefined';
 		}
 
-		// Check WP_ENVIRONMENT_TYPE.
-		if ( defined( 'WP_ENVIRONMENT_TYPE' ) && WP_ENVIRONMENT_TYPE ) {
-			$wp_environment_type = WP_ENVIRONMENT_TYPE;
-		} else {
-			$wp_environment_type = __( 'Undefined' );
-		}
-
 		$info['wp-constants'] = array(
 			'label'       => __( 'WordPress Constants' ),
 			'description' => __( 'These settings alter where and how parts of WordPress are loaded.' ),
@@ -254,13 +264,13 @@
 				),
 				'WP_HOME'             => array(
 					'label' => 'WP_HOME',
-					'value' => ( defined( 'WP_HOME' ) ? WP_HOME : __( 'Undefined' ) ),
-					'debug' => ( defined( 'WP_HOME' ) ? WP_HOME : 'undefined' ),
+					'value' => self::get_define_info( 'WP_HOME' ),
+					'debug' => self::get_define_info( 'WP_HOME' ),
 				),
 				'WP_SITEURL'          => array(
 					'label' => 'WP_SITEURL',
-					'value' => ( defined( 'WP_SITEURL' ) ? WP_SITEURL : __( 'Undefined' ) ),
-					'debug' => ( defined( 'WP_SITEURL' ) ? WP_SITEURL : 'undefined' ),
+					'value' => self::get_define_info( 'WP_SITEURL' ),
+					'debug' => self::get_define_info( 'WP_SITEURL' ),
 				),
 				'WP_CONTENT_DIR'      => array(
 					'label' => 'WP_CONTENT_DIR',
@@ -320,18 +330,18 @@
 				),
 				'WP_ENVIRONMENT_TYPE' => array(
 					'label' => 'WP_ENVIRONMENT_TYPE',
-					'value' => $wp_environment_type,
-					'debug' => $wp_environment_type,
+					'value' => self::get_define_info( 'WP_ENVIRONMENT_TYPE' ),
+					'debug' => self::get_define_info( 'WP_ENVIRONMENT_TYPE' ),
 				),
 				'DB_CHARSET'          => array(
 					'label' => 'DB_CHARSET',
-					'value' => ( defined( 'DB_CHARSET' ) ? DB_CHARSET : __( 'Undefined' ) ),
-					'debug' => ( defined( 'DB_CHARSET' ) ? DB_CHARSET : 'undefined' ),
+					'value' => self::get_define_info( 'DB_CHARSET' ),
+					'debug' => self::get_define_info( 'DB_CHARSET' ),
 				),
 				'DB_COLLATE'          => array(
 					'label' => 'DB_COLLATE',
-					'value' => ( defined( 'DB_COLLATE' ) ? DB_COLLATE : __( 'Undefined' ) ),
-					'debug' => ( defined( 'DB_COLLATE' ) ? DB_COLLATE : 'undefined' ),
+					'value' => self::get_define_info( 'DB_COLLATE' ),
+					'debug' => self::get_define_info( 'DB_COLLATE' ),
 				),
 			),
 		);