typed-array-byte-offset (original) (raw)
1.0.4 • Public • Published 5 months ago
typed-array-byte-offset 
Robustly get the byte offset of a Typed Array, or false if it is not a Typed Array. Works cross-realm, in every engine, even if the byteOffset property is overridden.
Example
var typedArrayByteOffset = require('typed-array-byte-offset'); var assert = require('assert');
assert.equal(false, typedArrayByteOffset(undefined)); assert.equal(false, typedArrayByteOffset(null)); assert.equal(false, typedArrayByteOffset(false)); assert.equal(false, typedArrayByteOffset(true)); assert.equal(false, typedArrayByteOffset([])); assert.equal(false, typedArrayByteOffset({})); assert.equal(false, typedArrayByteOffset(/a/g)); assert.equal(false, typedArrayByteOffset(new RegExp('a', 'g'))); assert.equal(false, typedArrayByteOffset(new Date())); assert.equal(false, typedArrayByteOffset(42)); assert.equal(false, typedArrayByteOffset(NaN)); assert.equal(false, typedArrayByteOffset(Infinity)); assert.equal(false, typedArrayByteOffset(new Number(42))); assert.equal(false, typedArrayByteOffset('foo')); assert.equal(false, typedArrayByteOffset(Object('foo'))); assert.equal(false, typedArrayByteOffset(function () {})); assert.equal(false, typedArrayByteOffset(function* () {})); assert.equal(false, typedArrayByteOffset(x => x * x)); assert.equal(false, typedArrayByteOffset([]));
const buffer = new ArrayBuffer(32);
assert.equal(8, typedArrayByteOffset(new Int8Array(buffer, 8))); assert.equal(8, typedArrayByteOffset(new Uint8Array(buffer, 8))); assert.equal(8, typedArrayByteOffset(new Uint8ClampedArray(buffer, 8))); assert.equal(4, typedArrayByteOffset(new Int16Array(buffer, 4))); assert.equal(4, typedArrayByteOffset(new Uint16Array(buffer, 4))); assert.equal(8, typedArrayByteOffset(new Int32Array(buffer, 8))); assert.equal(8, typedArrayByteOffset(new Uint32Array(buffer, 8))); assert.equal(16, typedArrayByteOffset(new Float32Array(buffer, 16))); assert.equal(16, typedArrayByteOffset(new Float64Array(buffer, 16))); assert.equal(16, typedArrayByteOffset(new BigInt64Array(buffer, 16))); assert.equal(16, typedArrayByteOffset(new BigUint64Array(buffer, 16)));
Tests
Simply clone the repo, npm install, and run npm test