1280052 - Buffer.slice is broken in FF 49.0a2 (2016-06-13)

Status: RESOLVED INVALID

(Firefox :: Untriaged, defect)

Description

[james]

What did you do?
================
We are using babel and it is including what appears to be Mozilla code.  I'm really not 100% sure, I appreciate your having a look.

This bug is really quite obvious when you see it.

1. I used webpack to include code that references the Buffer object.
2. In the console I run: new Buffer("abc").slice(0, 2).toString()


What happened?
==============
"abc" was returned

What should have happened?
==========================
"ab"

Is there anything else we should know?
======================================
I stepped into the code and found the error happens somewhere after this.subarray(start, end) is called.  It does not matter how large the buffer it, it will return the entire buffer when calling slice(0, buf.length - n).
```
Buffer.prototype.slice = function slice (start, end) {
  var len = this.length
  start = ~~start
  end = end === undefined ? len : ~~end

  if (start < 0) {
    start += len
    if (start < 0) start = 0
  } else if (start > len) {
    start = len
  }

  if (end < 0) {
    end += len
    if (end < 0) end = 0
  } else if (end > len) {
    end = len
  }

  if (end < start) end = start

  var newBuf
  if (Buffer.TYPED_ARRAY_SUPPORT) {
    newBuf = Buffer._augment(this.subarray(start, end))
  } else {
    var sliceLen = end - start
    newBuf = new Buffer(sliceLen, undefined)
    for (var i = 0; i < sliceLen; i++) {
      newBuf[i] = this[i + start]
    }
  }

  if (newBuf.length) newBuf.parent = this.parent || this

  return newBuf
}
```

Comment 1

[Nolan Lawson]

Seems this was a `buffer` issue and not a Firefox issue; for the backstory see:
- https://github.com/feross/buffer/pull/97
- https://github.com/feross/buffer/issues/120

Comment 2

[ovidiu boca[:Ovidiu]]

 Based on Nolan comment, I will close this as Resolved: Invalid. Feel free to reopen it if you have a different opinion.