read a buffer, like slicing while iterating pos

lib/bufferreader.js

@@ -22,6 +22,12 @@ BufferReader.prototype.eof = function eof() {
   return this.pos >= this.buf.length;
 };
 
+BufferReader.prototype.buffer = function(len) {
+  var buf = this.buf.slice(this.pos, this.pos + len);
+  this.pos = this.pos + len;
+  return buf;
+};
+
 BufferReader.prototype.read = function() {
   var buf = this.buf.slice(this.pos);
   this.pos = this.buf.length;

test/bufferreader.js

@@ -35,6 +35,20 @@ describe('BufferReader', function() {
 
   });
 
+  describe('#buffer', function() {
+
+    it('should return a buffer of this length', function() {
+      var buf = new Buffer(10);
+      buf.fill(0);
+      var br = new BufferReader(buf);
+      var buf2 = br.buffer(2);
+      buf2.length.should.equal(2);
+      br.eof().should.equal(false);
+      br.pos.should.equal(2);
+    });
+
+  });
+
   describe('read', function() {
     
     it('should return the same buffer', function() {