Add Promise support, bump to 2.0.1

README.md

@@ -42,7 +42,7 @@ Usage
 
 ### Modern API
 
-#### scrypt(password, salt, options, callback)
+#### scrypt(password, salt, options[, callback])
 
 Derives a key from password and salt and calls callback
 with derived key as the only argument.
@@ -52,12 +52,14 @@ zero setTimeout) at the given interruptSteps to avoid freezing the browser.
 If it's not set or set to zero, the callback is called immediately after the
 calculation, avoiding setImmediate.
 
+If callback is not set, `scrypt` returns a Promise.
+
 #### Arguments:
 
 * *password* — password (`string` or `Array` of bytes or `Uint8Array`)
 * *salt* — salt (`string` or `Array` of bytes or `Uint8Array`)
 * *options* — object with key derivation options
-* *callback* — callback function receiving result (`function (Array|Uint8Array|string)`)
+* *[callback]* — callback function receiving result (`function (Array|Uint8Array|string)`), omit for Promise
 
 ##### Options:
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "scrypt-async",
-  "version": "2.0.0",
+  "version": "2.0.1",
   "description": "Fast \"async\" scrypt implementation in JavaScript.",
   "main": "scrypt-async.js",
   "scripts": {
@@ -34,5 +34,8 @@
   "bugs": {
     "url": "https://github.com/dchest/scrypt-async-js/issues"
   },
-  "homepage": "https://github.com/dchest/scrypt-async-js"
+  "homepage": "https://github.com/dchest/scrypt-async-js",
+  "dependencies": {
+    "promise": "^8.0.1"
+  }
 }

scrypt-async.js

@@ -41,6 +41,7 @@
  * Pass 0 to have callback called immediately.
  *
  */
+var Promise = require('promise');
 function scrypt(password, salt, logN, r, dkLen, interruptStep, callback, encoding) {
   'use strict';
 
@@ -398,7 +399,7 @@ function scrypt(password, salt, logN, r, dkLen, interruptStep, callback, encodin
         throw new Error('scrypt: missing N parameter');
       }
     }
-    p = opts.p || 1;
+    p = opts.p;
     r = opts.r;
     dkLen = opts.dkLen || 32;
     interruptStep = opts.interruptStep || 0;
@@ -542,10 +543,22 @@ function scrypt(password, salt, logN, r, dkLen, interruptStep, callback, encodin
     interruptStep = 1000;
   }
 
-  if (interruptStep <= 0) {
-    calculateSync();
-  } else {
-    calculateAsync(0);
+  function run() {
+    if (interruptStep <= 0) {
+      calculateSync();
+    } else {
+      calculateAsync(0);
+    }
+  }
+
+  if(!callback){
+    // Promise
+    return new Promise(function(resolve) {
+      callback = resolve;
+      run();
+    })
+  }else {
+  	run();
   }
 }
 

test/unittests.js

@@ -516,6 +516,21 @@ function async_test_opts(i, interruptStep, done) {
   });
 }
 
+function async_test_opts_promise(i, interruptStep, done) {
+  var v = inputsWithP[i];
+  scrypt(v.password, v.salt, {
+    N: v.N,
+    r: v.r,
+    p: v.p,
+    dkLen: v.result.length,
+    interruptStep: interruptStep,
+    encoding: v.encoding
+  }).then(function(out) {
+    assert.deepEqual(v.result, out);
+    done();
+  })
+}
+
 
 describe('async input/output test with options and p with zero interruptStep', function() {
   this.timeout(100000);
@@ -546,3 +561,13 @@ describe('async input/output test with options and p', function() {
   // });
 
 });
+
+describe('async promise', function() {
+  this.timeout(100000);
+
+  var step = 0;
+
+  it('input 0', function(done) {
+    async_test_opts_promise(0, step, done);
+  });
+});