adding documentation on Node.js compatibility with UWP and how to test

README.md

@@ -18,3 +18,26 @@ Steps:
  * Set node_dir to the path of your Node.js clone
  * Set release_dir if desired (optional if copyrelease is not used)
  * Run "build.bat [x86|x64|arm] [copyrelease]"
+
+##To test:
+Follow the steps below to run [tests](https://github.com/joyent/node/tree/master/test) included with Node.js.
+
+ * Clone Node.js from https://github.com/microsoft/node
+ * Install the NTVS IoT Extension using the steps [here](http:https://ms-iot.github.io/content/en-US/win10/samples/NodejsWU.htm) and create a new Node.js (Windows Universal) project
+ * Copy <Node.js clone path>\tests to <Node.js UWP project path (location of .njsproj file)>\tests
+ * Right click on the test you want to run and select "Set as Node.js Startup File". The file text will be made bold (see test-assert.js example below)
+ ![Set test as Startup File]({{site.baseurl}}/images/test-startup-file.png)
+ * Press F5 (or click on Debug->Start Debugging menu) to run the test
+ * Console output can be redirected to file. You can view the logs on the device in c:\Users\DefaultAccount\AppData\Local\Packages\<Your app ID (get it from VS build logs)>\LocalState\nodeuwp.log
+
+##Node.js compatibility with UWP
+The following API's are not supported in Node.js UWP:
+
+ * Child Processes
+ * Cluster
+ * Debugger
+ * TTY
+
+There are a few other limitations in other modules. For example, the [fs](https://nodejs.org/api/fs.html) module can only access files within its the UWP package or within paths declared in the [package capabilities](https://msdn.microsoft.com/en-us/library/windows/apps/hh464936.aspx).
+
+Detailed documentation on which API's are supported in Node.js UWP can be found [here]({{site.baseurl}}/compatibility.xlsx).