UINT64_shiftRight-test.js 1.6 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495
  1. var assert = require('assert')
  2. var UINT64 = require('..').UINT64
  3. describe('shiftRight method', function () {
  4. describe('0>>1', function () {
  5. it('should return 0', function (done) {
  6. var u = UINT64(0).shiftRight(1)
  7. assert.equal( u.toNumber(), 0 )
  8. done()
  9. })
  10. })
  11. describe('4>>2', function () {
  12. it('should return 1', function (done) {
  13. var u = UINT64(4).shiftRight(2)
  14. assert.equal( u.toNumber(), 1 )
  15. done()
  16. })
  17. })
  18. describe('2^16>>16', function () {
  19. it('should return 1', function (done) {
  20. var n = Math.pow(2, 16)
  21. var u = UINT64(n).shiftRight(16)
  22. assert.equal( u.toNumber(), 1 )
  23. done()
  24. })
  25. })
  26. describe('1>>32', function () {
  27. it('should return 0', function (done) {
  28. var u = UINT64(1).shiftRight(32)
  29. assert.equal( u.toNumber(), 0 )
  30. done()
  31. })
  32. })
  33. describe('2^31>>31', function () {
  34. it('should return 1', function (done) {
  35. var u = UINT64('80000000', 16).shiftRight(31)
  36. assert.equal( u.toNumber(), 1 )
  37. done()
  38. })
  39. })
  40. describe('2^28>>28', function () {
  41. it('should return 1', function (done) {
  42. var u = UINT64('10000000', 16).shiftRight(28)
  43. assert.equal( u.toNumber(), 1 )
  44. done()
  45. })
  46. })
  47. describe('2^31+2^28>>31', function () {
  48. it('should return 1', function (done) {
  49. var u = UINT64('90000000', 16).shiftRight(31)
  50. assert.equal( u.toNumber(), 1 )
  51. done()
  52. })
  53. })
  54. describe('2^31+2^28>>28', function () {
  55. it('should return 9', function (done) {
  56. var u = UINT64('90000000', 16).shiftRight(28)
  57. assert.equal( u.toNumber(), 9 )
  58. done()
  59. })
  60. })
  61. })