buffer: add .from(), .alloc() and .allocUnsafe()

Several changes:

* Soft-Deprecate Buffer() constructors
* Add `Buffer.from()`, `Buffer.alloc()`, and `Buffer.allocUnsafe()`
* Add `--zero-fill-buffers` command line option
* Add byteOffset and length to `new Buffer(arrayBuffer)` constructor
* buffer.fill('') previously had no effect, now zero-fills
* Update the docs

PR-URL: https://github.com/nodejs/node/pull/4682
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
Reviewed-By: Stephen Belanger <admin@stephenbelanger.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/test/parallel/test-stream2-compatibility.js b/test/parallel/test-stream2-compatibility.js
index 2d62d63907..7731245659 100644
--- a/test/parallel/test-stream2-compatibility.js
+++ b/test/parallel/test-stream2-compatibility.js
@@ -10,8 +10,7 @@ var ondataCalled = 0;
 
 function TestReader() {
   R.apply(this);
-  this._buffer = new Buffer(100);
-  this._buffer.fill('x');
+  this._buffer = Buffer.alloc(100, 'x');
 
   this.on('data', function() {
     ondataCalled++;
@@ -22,7 +21,7 @@ util.inherits(TestReader, R);
 
 TestReader.prototype._read = function(n) {
   this.push(this._buffer);
-  this._buffer = new Buffer(0);
+  this._buffer = Buffer.alloc(0);
 };
 
 var reader = new TestReader();