docs: improve ValidationErrorItem docs

lib/errors/index.js

@@ -37,7 +37,7 @@ exports.SequelizeScopeError = SequelizeScopeError;
  * @param {string} message Error message
  * @param {Array} [errors] Array of ValidationErrorItem objects describing the validation errors
  *
- * @property errors An array of ValidationErrorItems
+ * @property errors {ValidationErrorItems[]}
  */
 class ValidationError extends BaseError {
   constructor(message, errors) {
@@ -234,20 +234,65 @@ exports.UnknownConstraintError = UnknownConstraintError;
  * @param {Object} [validatorKey] a validation "key", used for identification
  * @param {String} [fnName] property name of the BUILT-IN validator function that caused the validation error (e.g. "in" or "len"), if applicable
  * @param {String} [fnArgs] parameters used with the BUILT-IN validator function, if applicable
- *
- * @param {string} value The value that generated the error
  */
 class ValidationErrorItem {
   constructor(message, type, path, value, inst, validatorKey, fnName, fnArgs) {
+    /**
+     * An error message
+     *
+     * @type {String} message
+     */
     this.message = message || '';
+
+    /**
+     * The type/origin of the validation error
+     *
+     * @type {String}
+     */
     this.type = null;
+
+    /**
+     * The field that triggered the validation error
+     *
+     * @type {String}
+     */
     this.path = path || null;
+
+    /**
+     * The value that generated the error
+     *
+     * @type {String}
+     */
     this.value = value !== undefined ? value : null;
 
     this.origin = null;
+
+    /**
+     * The DAO instance that caused the validation error
+     *
+     * @type {Model}
+     */
     this.instance = inst || null;
+
+    /**
+     * A validation "key", used for identification
+     *
+     * @type {String}
+     */
     this.validatorKey = validatorKey || null;
+
+    /**
+     * Property name of the BUILT-IN validator function that caused the validation error (e.g. "in" or "len"), if applicable
+     *
+     * @type {String}
+     */
     this.validatorName = fnName || null;
+
+    /**
+     * Parameters used with the BUILT-IN validator function, if applicable
+     *
+     * @type {String}
+     */
     this.validatorArgs = fnArgs || [];
 
     if (type) {
@@ -278,6 +323,8 @@ class ValidationErrorItem {
    *                                            defaults to "." (fullstop). only used and validated if useTypeAsNS is TRUE.
    * @throws  {Error}                           thrown if NSSeparator is found to be invalid.
    * @return  {String}
+   *
+   * @private
    */
   getValidatorKey(useTypeAsNS, NSSeparator) {
     const useTANS = typeof useTypeAsNS === 'undefined' ?  true : !!useTypeAsNS;