Merge pull request #678 from eordano/feature/privkeyhex

Add functionality to create private key from a hex string

lib/privatekey.js

@@ -7,6 +7,7 @@ var networks = require('./networks');
 var base58check = require('./encoding/base58check');
 var Address = require('./address');
 var PublicKey = require('./publickey');
+var jsUtil = require('./util/js');
 
 /**
  *
@@ -51,7 +52,11 @@ var PrivateKey = function PrivateKey(data, network, compressed) {
   } else if (data instanceof Buffer || data instanceof Uint8Array) {
     info = PrivateKey._transformBuffer(data, network, compressed);
   } else if (typeof(data) === 'string'){
-    info = PrivateKey._transformWIF(data, network, compressed);
+    if (jsUtil.isHexa(data)) {
+      info.bn = BN(new Buffer(data, 'hex'));
+    } else {
+      info = PrivateKey._transformWIF(data, network, compressed);
+    }
   } else {
     throw new TypeError('First argument is an unrecognized data type.');
   }

test/privatekey.js

@@ -72,6 +72,13 @@ describe('PrivateKey', function() {
     }).should.throw('Invalid network');
   });
 
+  it('can be instantiated from a hex string', function() {
+    var privhex = '906977a061af29276e40bf377042ffbde414e496ae2260bbf1fa9d085637bfff';
+    var pubhex = '02a1633cafcc01ebfb6d78e39f687a1f0995c62fc95f51ead10a02ee0be551b5dc';
+    var privkey = new PrivateKey(privhex);
+    privkey.publicKey.toString().should.equal(pubhex);
+  });
+
   it('should not be able to instantiate because compressed is non-boolean', function() {
     (function() {
       var a = new PrivateKey(null, 'testnet', 'compressed');