6e9a8a09c41af23d6c2d264f79abb2649f177039f61d524cdc5b947589d02612f5fd6313125f8bc9ce37fa8e2952fbd1514e5df95d7572e2a5bde98ec2e00c 1.6 KB

12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849
  1. 'use strict';
  2. var $TypeError = require('es-errors/type');
  3. var floor = require('./floor');
  4. var IsFixedLengthArrayBuffer = require('./IsFixedLengthArrayBuffer');
  5. var IsTypedArrayOutOfBounds = require('./IsTypedArrayOutOfBounds');
  6. var TypedArrayElementSize = require('./TypedArrayElementSize');
  7. var isTypedArrayWithBufferWitnessRecord = require('../helpers/records/typed-array-with-buffer-witness-record');
  8. var typedArrayBuffer = require('typed-array-buffer');
  9. var typedArrayByteOffset = require('typed-array-byte-offset');
  10. var typedArrayLength = require('typed-array-length');
  11. // http://www.ecma-international.org/ecma-262/15.0/#sec-typedarraylength
  12. module.exports = function TypedArrayLength(taRecord) {
  13. if (!isTypedArrayWithBufferWitnessRecord(taRecord)) {
  14. throw new $TypeError('Assertion failed: `taRecord` must be a TypedArray With Buffer Witness Record');
  15. }
  16. if (IsTypedArrayOutOfBounds(taRecord)) {
  17. throw new $TypeError('Assertion failed: `taRecord` is out of bounds'); // step 1
  18. }
  19. var O = taRecord['[[Object]]']; // step 2
  20. var length = typedArrayLength(O);
  21. if (length !== 'AUTO') {
  22. return length; // step 3
  23. }
  24. if (IsFixedLengthArrayBuffer(typedArrayBuffer(O))) {
  25. throw new $TypeError('Assertion failed: array buffer is not fixed length'); // step 4
  26. }
  27. var byteOffset = typedArrayByteOffset(O); // step 5
  28. var elementSize = TypedArrayElementSize(O); // step 6
  29. var byteLength = taRecord['[[CachedBufferByteLength]]']; // step 7
  30. if (byteLength === 'DETACHED') {
  31. throw new $TypeError('Assertion failed: typed array is detached'); // step 8
  32. }
  33. return floor((byteLength - byteOffset) / elementSize); // step 9
  34. };