UINT32_shiftLeft-test.js 1.2 KB

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  1. var assert = require('assert')
  2. var UINT32 = require('..').UINT32
  3. describe('shiftLeft method', function () {
  4. describe('0<<1', function () {
  5. it('should return 0', function (done) {
  6. var u = UINT32(0).shiftLeft(1)
  7. assert.equal( u.toNumber(), 0 )
  8. done()
  9. })
  10. })
  11. describe('1<<2', function () {
  12. it('should return 4', function (done) {
  13. var u = UINT32(1).shiftLeft(2)
  14. assert.equal( u.toNumber(), 4 )
  15. done()
  16. })
  17. })
  18. describe('1<<16', function () {
  19. it('should return 2^16', function (done) {
  20. var n = Math.pow(2, 16)
  21. var u = UINT32(1).shiftLeft(16)
  22. assert.equal( u.toNumber(), n )
  23. done()
  24. })
  25. })
  26. describe('1<<32', function () {
  27. it('should return 0', function (done) {
  28. var u = UINT32(1).shiftLeft(32)
  29. assert.equal( u.toNumber(), 0 )
  30. done()
  31. })
  32. })
  33. describe('1<<31', function () {
  34. it('should return 2^31', function (done) {
  35. var u = UINT32(1).shiftLeft(31)
  36. assert.equal( u.toString(16), '80000000' )
  37. done()
  38. })
  39. })
  40. describe('9<<28', function () {
  41. it('should return 2^31', function (done) {
  42. var u = UINT32(9).shiftLeft(28)
  43. assert.equal( u.toString(16), '90000000' )
  44. done()
  45. })
  46. })
  47. })