JSTests/test262/test/built-ins/TypedArrayConstructors/from/mapfn-is-not-callable.js

// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-%typedarray%.from
description: Throw a TypeError exception is mapfn is not callable
info: |
  22.2.2.1 %TypedArray%.from ( source [ , mapfn [ , thisArg ] ] )

  ...
  3. If mapfn was supplied and mapfn is not undefined, then
    a. If IsCallable(mapfn) is false, throw a TypeError exception.
  ...
includes: [testTypedArray.js]
features: [Symbol, Symbol.iterator, TypedArray]
---*/

var getIterator = 0;
var arrayLike = {};
Object.defineProperty(arrayLike, Symbol.iterator, {
  get: function() {
    getIterator++;
  }
});

testWithTypedArrayConstructors(function(TA) {
  assert.throws(TypeError, function() {
    TA.from(arrayLike, null);
  }, "mapfn is null");

  assert.throws(TypeError, function() {
    TA.from(arrayLike, 42);
  }, "mapfn is a number");

  assert.throws(TypeError, function() {
    TA.from(arrayLike, "");
  }, "mapfn is a string");

  assert.throws(TypeError, function() {
    TA.from(arrayLike, {});
  }, "mapfn is an ordinary object");

  assert.throws(TypeError, function() {
    TA.from(arrayLike, []);
  }, "mapfn is an array");

  assert.throws(TypeError, function() {
    TA.from(arrayLike, true);
  }, "mapfn is a boolean");

  var s = Symbol("1");
  assert.throws(TypeError, function() {
    TA.from(arrayLike, s);
  }, "mapfn is a symbol");

  assert.sameValue(
    getIterator, 0,
    "IsCallable(mapfn) check occurs before getting source[@@iterator]"
  );
});