fix: throw error if parts contains an element that isn't a string or number

Fix #13

Author: vkarpov15

lib/index.js

@@ -64,6 +64,9 @@ exports.get = function(path, o, special, map) {
 
  for (var i = 0; i < parts.length; ++i) {
  part = parts[i];
+ if (typeof parts[i] !== 'string' && typeof parts[i] !== 'number') {
+ throw new TypeError('Each segment of path to `get()` must be a string or number, got ' + typeof parts[i]);
+ }
 
  if (Array.isArray(obj) && !/^\d+$/.test(part)) {
  // reading a property from the array items
@@ -112,6 +115,9 @@ exports.has = function(path, o) {
  var len = parts.length;
  var cur = o;
  for (var i = 0; i < len; ++i) {
+ if (typeof parts[i] !== 'string' && typeof parts[i] !== 'number') {
+ throw new TypeError('Each segment of path to `has()` must be a string or number, got ' + typeof parts[i]);
+ }
  if (cur == null || typeof cur !== 'object' || !(parts[i] in cur)) {
  return false;
  }
@@ -143,6 +149,9 @@ exports.unset = function(path, o) {
  if (cur == null || typeof cur !== 'object' || !(parts[i] in cur)) {
  return false;
  }
+ if (typeof parts[i] !== 'string' && typeof parts[i] !== 'number') {
+ throw new TypeError('Each segment of path to `unset()` must be a string or number, got ' + typeof parts[i]);
+ }
  // Disallow any updates to __proto__ or special properties.
  if (ignoreProperties.indexOf(parts[i]) !== -1) {
  return false;
@@ -193,6 +202,9 @@ exports.set = function(path, val, o, special, map, _copying) {
  if (null == o) return;
 
  for (var i = 0; i < parts.length; ++i) {
+ if (typeof parts[i] !== 'string' && typeof parts[i] !== 'number') {
+ throw new TypeError('Each segment of path to `set()` must be a string or number, got ' + typeof parts[i]);
+ }
  // Silently ignore any updates to `__proto__`, these are potentially
  // dangerous if using mpath with unsanitized data.
  if (ignoreProperties.indexOf(parts[i]) !== -1) {