streams2 push and high water marks

[Raynos]

When you call stream.push(data) it will return true indicating push more data in if the needReadable flag is set. This holds true even if we are above the high water mark. This can lead to the stream being filled above the high water mark pulling too much data into memory

consider the following gist

I expect the example below to indicate me that I should stop pushing data into this stream.

var Readable = require('stream').Readable
var assert = require('assert')

var count = 100
var list = []
for (var i = 0; i < count; i++) {
    list.push(i)
}

var s = Readable({
    objectMode: true
    , highWaterMark: 100
})

s._read = function () {
    var bools = list.map(function (i) {
        return s.push(i)
    })

    assert.ok(bools.every(function (x) {
        return x === true
    }))

    var needMore = s.push(100)
    // IS ACTUALLY TRUE because s.needReadable is set
    // I think if push makes it go over the high water mark we should
    // return false and ignore the fact we need a readable.
    assert.equal(needMore, false)

    // console.log("s", s._readableState)
}

s.read(0)

[isaacs]

Fixed on master.