stream: don't create unnecessary buffers in Readable

If there is an encoding, and we do 'stream.push(chunk, enc)', and the
encoding argument matches the stated encoding, then we're converting from
a string, to a buffer, and then back to a string.  Of course, this is a
completely pointless bit of work, so it's best to avoid it when we know
that we can do so safely.

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/_stream_transform.js b/lib/_stream_transform.js
index 8a00d343b6..e925b4bb51 100644
--- a/lib/_stream_transform.js
+++ b/lib/_stream_transform.js
@@ -135,9 +135,9 @@ function Transform(options) {
   });
 }
 
-Transform.prototype.push = function(chunk) {
+Transform.prototype.push = function(chunk, encoding) {
   this._transformState.needTransform = false;
-  return Duplex.prototype.push.call(this, chunk);
+  return Duplex.prototype.push.call(this, chunk, encoding);
 };
 
 // This is the part where you do stuff!