give Base58Check the same fromString toString

...interface like the rest of the classes

index.js

@@ -25,7 +25,7 @@ bitcore.expmt.Stealth = require('./lib/expmt/stealth');
 bitcore.deps = {};
 bitcore.deps.bnjs = require('bn.js');
 bitcore.deps.bs58 = require('bs58');
-bitcore.deps.buffer = Buffer;
+bitcore.deps.Buffer = Buffer;
 bitcore.deps.elliptic = require('elliptic');
 bitcore.deps.hashjs = require('hash.js');
 bitcore.deps.sha512 = require('sha512');

lib/base58check.js

@@ -1,26 +1,20 @@
 var base58 = require('./base58');
 var sha256sha256 = require('./hash').sha256sha256;
 
-var base58check = module.exports;
-
-base58check.encode = function(buf) {
-  if (!Buffer.isBuffer(buf))
-    throw new Error('base58check: Input must be a buffer');
-  var checkedBuf = new Buffer(buf.length + 4);
-  var hash = sha256sha256(buf);
-  buf.copy(checkedBuf);
-  hash.copy(checkedBuf, buf.length);
-  return base58.encode(checkedBuf);
+var Base58Check = function Base58Check(buf) {
+  if (!(this instanceof Base58Check))
+    return new Base58Check(buf);
+  this.buf = buf;
 };
 
-base58check.decode = function(s) {
+Base58Check.decode = function(s) {
   if (typeof s !== 'string')
-    throw new Error('base58check: Input must be a string');
+    throw new Error('Base58Check: Input must be a string');
 
   var buf = base58.decode(s);
 
   if (buf.length < 4)
-    throw new Error("base58check: Input string too short");
+    throw new Error("Base58Check: Input string too short");
 
   var data = buf.slice(0, -4);
   var csum = buf.slice(-4);
@@ -29,7 +23,38 @@ base58check.decode = function(s) {
   var hash4 = hash.slice(0, 4);
 
   if (csum.toString('hex') !== hash4.toString('hex'))
-    throw new Error("base58check: Checksum mismatch");
+    throw new Error("Base58Check: Checksum mismatch");
 
   return data;
 };
+
+Base58Check.encode = function(buf) {
+  if (!Buffer.isBuffer(buf))
+    throw new Error('Base58Check: Input must be a buffer');
+  var checkedBuf = new Buffer(buf.length + 4);
+  var hash = sha256sha256(buf);
+  buf.copy(checkedBuf);
+  hash.copy(checkedBuf, buf.length);
+  return base58.encode(checkedBuf);
+};
+
+Base58Check.prototype.fromBuffer = function(buf) {
+  this.buf = buf;
+  return this;
+};
+
+Base58Check.prototype.fromString = function(str) {
+  var buf = Base58Check.decode(str);
+  this.buf = buf;
+  return this;
+};
+
+Base58Check.prototype.toBuffer = function() {
+  return this.buf;
+};
+
+Base58Check.prototype.toString = function() {
+  return Base58Check.encode(this.buf);
+};
+
+module.exports = Base58Check;

test/test.base58check.js

@@ -1,21 +1,31 @@
 var should = require('chai').should();
-var base58check = require('../lib/base58check');
+var Base58Check = require('../lib/Base58Check');
 var base58 = require('../lib/base58');
 
 describe('Base58check', function() {
   var buf = new Buffer([0, 1, 2, 3, 253, 254, 255]);
   var enc = "14HV44ipwoaqfg";
 
+  it('should make an instance with "new"', function() {
+    var b58 = new Base58Check();
+    should.exist(b58);
+  });
+
+  it('should make an instance without "new"', function() {
+    var b58 = Base58Check();
+    should.exist(b58);
+  });
+
   describe('#encode', function() {
 
     it('should encode the buffer accurately', function() {
-      base58check.encode(buf).should.equal(enc);
+      Base58Check.encode(buf).should.equal(enc);
     });
 
     it('should throw an error when the input is not a buffer', function() {
       (function() {
-        base58check.encode("string")
-      }).should.throw('base58check: Input must be a buffer');
+        Base58Check.encode("string")
+      }).should.throw('Base58Check: Input must be a buffer');
     });
 
   });
@@ -23,19 +33,19 @@ describe('Base58check', function() {
   describe('#decode', function() {
 
     it('should decode this encoded value correctly', function() {
-      base58check.decode(enc).toString('hex').should.equal(buf.toString('hex'));
+      Base58Check.decode(enc).toString('hex').should.equal(buf.toString('hex'));
     });
 
     it('should throw an error when input is not a string', function() {
       (function() {
-        base58check.decode(5);
-      }).should.throw('base58check: Input must be a string');
+        Base58Check.decode(5);
+      }).should.throw('Base58Check: Input must be a string');
     });
 
     it('should throw an error when input is too short', function() {
       (function() {
-        base58check.decode(enc.slice(0, 1));
-      }).should.throw('base58check: Input string too short');
+        Base58Check.decode(enc.slice(0, 1));
+      }).should.throw('Base58Check: Input string too short');
     });
 
     it('should throw an error when there is a checksum mismatch', function() {
@@ -43,8 +53,47 @@ describe('Base58check', function() {
       buf2[0] = buf2[0] + 1;
       var enc2 = base58.encode(buf2);
       (function() {
-        base58check.decode(enc2);
-      }).should.throw('base58check: Checksum mismatch');
+        Base58Check.decode(enc2);
+      }).should.throw('Base58Check: Checksum mismatch');
+    });
+
+  });
+
+  describe('#fromBuffer', function() {
+    
+    it('should not fail', function() {
+      should.exist(Base58Check().fromBuffer(buf));
+    });
+
+    it('should set buffer', function() {
+      var b58 = Base58Check().fromBuffer(buf);
+      b58.buf.toString('hex').should.equal(buf.toString('hex'));
+    });
+
+  });
+
+  describe('#fromString', function() {
+
+    it('should convert this known string to a buffer', function() {
+      Base58Check().fromString(enc).toBuffer().toString('hex').should.equal(buf.toString('hex'));
+    });
+
+  });
+
+  describe('#toBuffer', function() {
+
+    it('should return the buffer', function() {
+      var b58 = Base58Check(buf);
+      b58.buf.toString('hex').should.equal(buf.toString('hex'));
+    });
+
+  });
+
+  describe('#toString', function() {
+
+    it('should return the buffer', function() {
+      var b58 = Base58Check(buf);
+      b58.toString().should.equal(enc);
     });
 
   });