Added default assert definition and a second definition for writeFile. Also added a basic test file. Will be expanded more later.

node/node-tests.ts

@@ -0,0 +1,30 @@
+/// <reference path="node.d.ts" />
+
+import assert = module("assert");
+import fs = module("fs");
+
+assert(1 + 1 - 2 === 0, "The universe isn't how it should.");
+
+assert.deepEqual({ x: { y: 3 } }, { x: { y: 3 } }, "DEEP WENT DERP");
+
+assert.equal(3, "3", "uses == comparator");
+
+assert.notStrictEqual(2, "2", "uses === comparator");
+
+assert.throws(() => { throw "a hammer at your face"; }, undefined, "DODGED IT");
+
+assert.doesNotThrow(() => {
+    if (false) { throw "a hammer at your face"; }
+}, undefined, "What the...*crunch*");
+
+
+fs.writeFile("thebible.txt",
+    "Do unto others as you would have them do unto you.",
+    assert.ifError);
+
+fs.writeFile("Harry Potter",
+            "\"You be wizzing, Harry,\" jived Dumbledore.",
+            {
+                encoding: "ascii"
+            },
+            assert.ifError);

node/node.d.ts

@@ -776,7 +776,8 @@ declare module "fs" {
     export function readFile(filename: string, callback: (err: Error, data: NodeBuffer) => void ): void;
     export function readFileSync(filename: string): NodeBuffer;
     export function readFileSync(filename: string, encoding: string): string;
-    export function writeFile(filename: string, data: any, encoding?: string, callback?: Function): void;
+    export function writeFile(filename: string, data: any, callback?: (err) => void): void;
+    export function writeFile(filename: string, data: any, options: { encoding?: string; mode?: number; flag?: string; }, callback?: Function): void;
     export function writeFileSync(filename: string, data: any, encoding?: string): void;
     export function appendFile(filename: string, data: any, encoding?: string, callback?: Function): void;
     export function appendFileSync(filename: string, data: any, encoding?: string): void;
@@ -1014,6 +1015,7 @@ declare module "util" {
 }
 
 declare module "assert" {
+    export function (booleanValue: bool, message?: string);
     export function fail(actual: any, expected: any, message: string, operator: string): void;
     export function assert(value: any, message: string): void;
     export function ok(value: any, message?: string): void;
@@ -1054,4 +1056,4 @@ declare module "domain" {
     export function bind(cb: (er: Error, data: any) =>any): any;
     export function intercept(cb: (data: any) => any): any;
     export function dispose(): void;
-}
+}