diff -r 2f6f6f7551ca -r 32102edaa81b web/wp-includes/class-wp-error.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/wp-includes/class-wp-error.php	Mon Nov 19 18:26:13 2012 +0100
@@ -0,0 +1,210 @@
+<?php
+/**
+ * WordPress Error API.
+ *
+ * Contains the WP_Error class and the is_wp_error() function.
+ *
+ * @package WordPress
+ */
+
+/**
+ * WordPress Error class.
+ *
+ * Container for checking for WordPress errors and error messages. Return
+ * WP_Error and use {@link is_wp_error()} to check if this class is returned.
+ * Many core WordPress functions pass this class in the event of an error and
+ * if not handled properly will result in code errors.
+ *
+ * @package WordPress
+ * @since 2.1.0
+ */
+class WP_Error {
+	/**
+	 * Stores the list of errors.
+	 *
+	 * @since 2.1.0
+	 * @var array
+	 * @access private
+	 */
+	var $errors = array();
+
+	/**
+	 * Stores the list of data for error codes.
+	 *
+	 * @since 2.1.0
+	 * @var array
+	 * @access private
+	 */
+	var $error_data = array();
+
+	/**
+	 * Constructor - Sets up error message.
+	 *
+	 * If code parameter is empty then nothing will be done. It is possible to
+	 * add multiple messages to the same code, but with other methods in the
+	 * class.
+	 *
+	 * All parameters are optional, but if the code parameter is set, then the
+	 * data parameter is optional.
+	 *
+	 * @since 2.1.0
+	 *
+	 * @param string|int $code Error code
+	 * @param string $message Error message
+	 * @param mixed $data Optional. Error data.
+	 * @return WP_Error
+	 */
+	function __construct($code = '', $message = '', $data = '') {
+		if ( empty($code) )
+			return;
+
+		$this->errors[$code][] = $message;
+
+		if ( ! empty($data) )
+			$this->error_data[$code] = $data;
+	}
+
+	/**
+	 * Retrieve all error codes.
+	 *
+	 * @since 2.1.0
+	 * @access public
+	 *
+	 * @return array List of error codes, if available.
+	 */
+	function get_error_codes() {
+		if ( empty($this->errors) )
+			return array();
+
+		return array_keys($this->errors);
+	}
+
+	/**
+	 * Retrieve first error code available.
+	 *
+	 * @since 2.1.0
+	 * @access public
+	 *
+	 * @return string|int Empty string, if no error codes.
+	 */
+	function get_error_code() {
+		$codes = $this->get_error_codes();
+
+		if ( empty($codes) )
+			return '';
+
+		return $codes[0];
+	}
+
+	/**
+	 * Retrieve all error messages or error messages matching code.
+	 *
+	 * @since 2.1.0
+	 *
+	 * @param string|int $code Optional. Retrieve messages matching code, if exists.
+	 * @return array Error strings on success, or empty array on failure (if using code parameter).
+	 */
+	function get_error_messages($code = '') {
+		// Return all messages if no code specified.
+		if ( empty($code) ) {
+			$all_messages = array();
+			foreach ( (array) $this->errors as $code => $messages )
+				$all_messages = array_merge($all_messages, $messages);
+
+			return $all_messages;
+		}
+
+		if ( isset($this->errors[$code]) )
+			return $this->errors[$code];
+		else
+			return array();
+	}
+
+	/**
+	 * Get single error message.
+	 *
+	 * This will get the first message available for the code. If no code is
+	 * given then the first code available will be used.
+	 *
+	 * @since 2.1.0
+	 *
+	 * @param string|int $code Optional. Error code to retrieve message.
+	 * @return string
+	 */
+	function get_error_message($code = '') {
+		if ( empty($code) )
+			$code = $this->get_error_code();
+		$messages = $this->get_error_messages($code);
+		if ( empty($messages) )
+			return '';
+		return $messages[0];
+	}
+
+	/**
+	 * Retrieve error data for error code.
+	 *
+	 * @since 2.1.0
+	 *
+	 * @param string|int $code Optional. Error code.
+	 * @return mixed Null, if no errors.
+	 */
+	function get_error_data($code = '') {
+		if ( empty($code) )
+			$code = $this->get_error_code();
+
+		if ( isset($this->error_data[$code]) )
+			return $this->error_data[$code];
+		return null;
+	}
+
+	/**
+	 * Append more error messages to list of error messages.
+	 *
+	 * @since 2.1.0
+	 * @access public
+	 *
+	 * @param string|int $code Error code.
+	 * @param string $message Error message.
+	 * @param mixed $data Optional. Error data.
+	 */
+	function add($code, $message, $data = '') {
+		$this->errors[$code][] = $message;
+		if ( ! empty($data) )
+			$this->error_data[$code] = $data;
+	}
+
+	/**
+	 * Add data for error code.
+	 *
+	 * The error code can only contain one error data.
+	 *
+	 * @since 2.1.0
+	 *
+	 * @param mixed $data Error data.
+	 * @param string|int $code Error code.
+	 */
+	function add_data($data, $code = '') {
+		if ( empty($code) )
+			$code = $this->get_error_code();
+
+		$this->error_data[$code] = $data;
+	}
+}
+
+/**
+ * Check whether variable is a WordPress Error.
+ *
+ * Looks at the object and if a WP_Error class. Does not check to see if the
+ * parent is also WP_Error, so can't inherit WP_Error and still use this
+ * function.
+ *
+ * @since 2.1.0
+ *
+ * @param mixed $thing Check if unknown variable is WordPress Error object.
+ * @return bool True, if WP_Error. False, if not WP_Error.
+ */
+function is_wp_error($thing) {
+	if ( is_object($thing) && is_a($thing, 'WP_Error') )
+		return true;
+	return false;
+}