system_assignation/node_modules/cuint/test/UINT64_subtract-test.js

76 lines
1.4 KiB
JavaScript

var assert = require('assert')
var UINT64 = require('..').UINT64
describe('subtract method', function () {
describe('0-0', function () {
it('should return 0', function (done) {
var u = UINT64(0).subtract( UINT64(0) )
assert.equal( u.toNumber(), 0 )
done()
})
})
describe('1-0', function () {
it('should return 1', function (done) {
var u = UINT64(1).subtract( UINT64(0) )
assert.equal( u.toNumber(), 1 )
done()
})
})
describe('0-1', function () {
it('should return -1', function (done) {
var u = UINT64(0).subtract( UINT64(1) )
assert.equal( u.toNumber(), -1 )
done()
})
})
describe('low bit-high bit', function () {
it('should return 0', function (done) {
var n = Math.pow(2, 17)
var u = UINT64(1).subtract( UINT64(n) )
assert.equal( u.toNumber(), 1-n )
done()
})
})
describe('high bit-low bit', function () {
it('should return n', function (done) {
var n = Math.pow(2, 17)
var u = UINT64(n).subtract( UINT64(123) )
assert.equal( u.toNumber(), n - 123 )
done()
})
})
describe('high bit-high bit', function () {
it('should return n', function (done) {
var n = Math.pow(2, 17)
var u = UINT64(n+1).subtract( UINT64(n) )
assert.equal( u.toNumber(), 1 )
done()
})
})
})