x.js

test("high water mark", function (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)
})