Add unit test and documentation for __getPath method.

Author: ElliotNB

README.md

@@ -1,6 +1,6 @@
 # :eyes: Observable Slim
 
-[![Build Status](https://travis-ci.org/ElliotNB/observable-slim.svg?branch=master)](https://travis-ci.org/ElliotNB/observable-slim) [![Coverage Status](https://coveralls.io/repos/github/ElliotNB/observable-slim/badge.svg)](https://coveralls.io/github/ElliotNB/observable-slim)
+[![Build Status](https://travis-ci.org/ElliotNB/observable-slim.svg?branch=master)](https://travis-ci.org/ElliotNB/observable-slim) [![Coverage Status](https://coveralls.io/repos/github/ElliotNB/observable-slim/badge.svg)](https://coveralls.io/github/ElliotNB/observable-slim) [![Monthly Downloads](https://img.shields.io/npm/dm/observable-slim.svg)](https://www.npmjs.com/package/observable-slim)
 
 https://github.com/elliotnb/observable-slim
 
@@ -25,7 +25,7 @@ down to roughly 3000 characters.
 Also available via NPM:
 
 ```
-$ npm install observable-slim
+$ npm install observable-slim --save
 ```
 
 ## Usage
@@ -210,6 +210,21 @@ function traverseUp(childObj) {
 traverseUp(proxy.hello.foo);
 ```
 
+**Note:** This functionality is not supported by the ES5 Proxy polyfill.
+
+### Retrieve the path of an object relative to the top-level observer
+
+ObservablesSlim also allows you to retrieve the full path of an object relative to the top-level observed object:
+
+```javascript
+var data = {"foo":"bar","arr":[{"test":{}}],"test":{"deeper":{}}};
+var p = ObservableSlim.create(data, false, function(changes) {});
+
+console.log(p.test.deeper.__getPath); // logs "test.deeper"
+
+```
+
+**Note:** This functionality is not supported by the ES5 Proxy polyfill.
 
 ## Requirements
 

observable-slim.js

@@ -157,7 +157,9 @@ var ObservableSlim = (function() {
 						parentPath.splice(-(i+1),(i+1));
 						return _getProperty(observable.parentProxy, parentPath.join("."));
 					}
+				// return the full path of the current object relative to the parent observable
 				} else if (property === "__getPath") {
+					// strip off the 12 characters for ".__getParent"
 					var parentPath = _getPath(target, "__getParent");
 					return parentPath.slice(0, -12);
 				}

test/test.js

@@ -766,4 +766,15 @@ function suite(proxy) {
 
 	});
 
+	it('41. Verify __getPath returns correct path (not supported with ES5 polyfill).', () => {
+		if (global.Proxy === global.NativeProxy) {
+			var data = {"foo":"bar","arr":[{"test":{}}],"test":{"deeper":{}}};
+			var p = ObservableSlim.create(data, false, function(changes) {});
+			
+			expect(p.test.deeper.__getPath).to.equal("test.deeper");
+			expect(p.arr[0].test.__getPath).to.equal("arr.0.test");
+		}
+		
+	});
+	
 };