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// fix up to ES6 semantics
// Tests for TypedArray#copyWithin
load(libdir + "asserts.js");
const constructors = [
Int8Array,
Uint8Array,
Uint8ClampedArray,
Int16Array,
Uint16Array,
Int32Array,
Uint32Array,
Float16Array,
Float32Array,
Float64Array
];
for (var constructor of constructors) {
assertEq(constructor.prototype.copyWithin.length, 2);
// works with two arguments
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0, 3),
new constructor([4, 5, 3, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(1, 3),
new constructor([1, 4, 5, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(1, 2),
new constructor([1, 3, 4, 5, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(2, 2),
new constructor([1, 2, 3, 4, 5]));
// works with three arguments
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0, 3, 4),
new constructor([4, 2, 3, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(1, 3, 4),
new constructor([1, 4, 3, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(1, 2, 4),
new constructor([1, 3, 4, 4, 5]));
// works with negative arguments
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0, -2),
new constructor([4, 5, 3, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0, -2, -1),
new constructor([4, 2, 3, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(-4, -3, -2),
new constructor([1, 3, 3, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(-4, -3, -1),
new constructor([1, 3, 4, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(-4, -3),
new constructor([1, 3, 4, 5, 5]));
// throws on null/undefined values
assertThrowsInstanceOf(function() {
constructor.prototype.copyWithin.call(null, 0, 3);
}, TypeError, "Assert that copyWithin fails if this value is null");
assertThrowsInstanceOf(function() {
var throw42 = { valueOf: function() { throw 42; } };
constructor.prototype.copyWithin.call(null, throw42, throw42, throw42);
}, TypeError, "Assert that copyWithin fails if this value is null");
assertThrowsInstanceOf(function() {
var throw42 = { valueOf: function() { throw 42; } };
constructor.prototype.copyWithin.call(undefined, throw42, throw42, throw42);
}, TypeError, "Assert that copyWithin fails if this value is undefined");
assertThrowsInstanceOf(function() {
constructor.prototype.copyWithin.call(undefined, 0, 3);
}, TypeError, "Assert that copyWithin fails if this value is undefined");
// test with this value as string
assertThrowsInstanceOf(function() {
constructor.prototype.copyWithin.call("hello world", 0, 3);
}, TypeError, "Assert that copyWithin fails if this value is string");
assertThrowsInstanceOf(function() {
var throw42 = { valueOf: function() { throw 42; } };
constructor.prototype.copyWithin.call("hello world", throw42, throw42, throw42);
}, TypeError, "Assert that copyWithin fails if this value is string");
// test with target > start on 2 arguments
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(3, 0),
new constructor([1, 2, 3, 1, 2]));
// test with target > start on 3 arguments
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(3, 0, 4),
new constructor([1, 2, 3, 1, 2]));
// test on fractional arguments
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0.2, 3.9),
new constructor([4, 5, 3, 4, 5]));
// test with -0
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(-0, 3),
new constructor([4, 5, 3, 4, 5]));
// test with arguments more than this.length
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0, 7),
new constructor([1, 2, 3, 4, 5]));
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(7, 0),
new constructor([1, 2, 3, 4, 5]));
// test with arguments less than -this.length
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(-7, 0),
new constructor([1, 2, 3, 4, 5]));
// test with arguments equal to -this.length
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(-5, 0),
new constructor([1, 2, 3, 4, 5]));
// test on empty constructor
assertDeepEq(new constructor([]).copyWithin(0, 3),
new constructor([]));
// test with target range being shorter than end - start
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(2, 1, 4),
new constructor([1, 2, 2, 3, 4]));
// test overlapping ranges
arr = new constructor([1, 2, 3, 4, 5]);
arr.copyWithin(2, 1, 4);
assertDeepEq(arr.copyWithin(2, 1, 4),
new constructor([1, 2, 2, 2, 3]));
// undefined as third argument
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0, 3, undefined),
new constructor([4, 5, 3, 4, 5]));
// test that this.length is never called
arr = new constructor([0, 1, 2, 3, 5]);
Object.defineProperty(arr, "length", {
get: function () { throw new Error("length accessor called"); }
});
arr.copyWithin(1, 3);
var large = 10000;
// test on a large constructor
arr = new constructor(large);
assertDeepEq(arr.copyWithin(45, 900), arr);
// test on floating point numbers
for (var i = 0; i < large; i++) {
arr[i] = Math.random();
}
arr.copyWithin(45, 900);
// test on constructor of objects
for (var i = 0; i < large; i++) {
arr[i] = { num: Math.random() };
}
arr.copyWithin(45, 900);
// test constructor length remains same
assertEq(arr.length, large);
// test null on third argument is handled correctly
assertDeepEq(new constructor([1, 2, 3, 4, 5]).copyWithin(0, 3, null),
new constructor([1, 2, 3, 4, 5]));
//Any argument referenced, but not provided, has the value |undefined|
var tarray = new constructor(8);
try
{
tarray.copyWithin({ valueOf: function() { throw 42; } });
throw new Error("expected to throw");
}
catch (e)
{
assertEq(e, 42, "should have failed converting target to index");
}
function detachAndConvertTo(x) {
return { valueOf() {
detachArrayBuffer(tarray.buffer);
return x;
} };
}
// Detaching during argument processing triggers a TypeError.
tarray = new constructor([1, 2, 3, 4, 5]);
try
{
tarray.copyWithin(0, 3, detachAndConvertTo(4));
throw new Error("expected to throw");
}
catch (e)
{
assertEq(e instanceof TypeError, true,
"expected throw with detached buffer during set");
}
// ...unless no elements are to be copied.
tarray = new constructor([1, 2, 3, 4, 5]);
assertDeepEq(tarray.copyWithin(0, 3, detachAndConvertTo(3)),
new constructor([]));
/* // fails, unclear whether it should, disabling for now
// test with a proxy object
var handler = {
get: function(recipient, name) {
return recipient[name] + 2;
}
};
var p = new Proxy(new constructor([1, 2, 3, 4, 5]), handler);
assertThrowsInstanceOf(function() {
constructor.prototype.copyWithin.call(p, 0, 3);
}, TypeError, "Assert that copyWithin fails if used with a proxy object");
*/
}