wallet-core/node_modules/crypto-browserify/test/random-fill.js

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2017-12-10 21:51:33 +01:00
var test = require('tape')
var crypto = require('../')
var Buffer = require('safe-buffer').Buffer
test('get error message', function (t) {
try {
var b = crypto.randomFillSync(Buffer.alloc(10))
t.ok(Buffer.isBuffer(b))
t.end()
} catch (err) {
t.ok(/not supported/.test(err.message), '"not supported" is in error message')
t.end()
}
})
test('randomfill', function (t) {
t.plan(5)
t.equal(crypto.randomFillSync(Buffer.alloc(10)).length, 10)
t.ok(Buffer.isBuffer(crypto.randomFillSync(Buffer.alloc(10))))
crypto.randomFill(Buffer.alloc(10), function (ex, bytes) {
t.error(ex)
t.equal(bytes.length, 10)
t.ok(Buffer.isBuffer(bytes))
t.end()
})
})
test('seems random', function (t) {
var L = 1000
var b = crypto.randomFillSync(Buffer.alloc(L))
var mean = [].reduce.call(b, function (a, b) {
return a + b
}, 0) / L
// test that the random numbers are plausably random.
// Math.random() will pass this, but this will catch
// terrible mistakes such as this blunder:
// https://github.com/dominictarr/crypto-browserify/commit/3267955e1df7edd1680e52aeede9a89506ed2464#commitcomment-7916835
// this doesn't check that the bytes are in a random *order*
// but it's better than nothing.
var expected = 256 / 2
var smean = Math.sqrt(mean)
// console.log doesn't work right on testling, *grumble grumble*
console.log(JSON.stringify([expected - smean, mean, expected + smean]))
t.ok(mean < expected + smean)
t.ok(mean > expected - smean)
t.end()
})