Function TestCopyWithin

deps/v8/test/mjsunit/typedarray-resizablearraybuffer.js:1824–1962

(helper, oobThrows)

})();

function TestCopyWithin(helper, oobThrows) {
  for (let ctor of ctors) {
    const rab = CreateResizableArrayBuffer(4 * ctor.BYTES_PER_ELEMENT,
                                           8 * ctor.BYTES_PER_ELEMENT);
    const fixedLength = new ctor(rab, 0, 4);
    const fixedLengthWithOffset = new ctor(rab, 2 * ctor.BYTES_PER_ELEMENT, 2);
    const lengthTracking = new ctor(rab, 0);
    const lengthTrackingWithOffset = new ctor(rab, 2 * ctor.BYTES_PER_ELEMENT);

    // Write some data into the array.
    const taWrite = new ctor(rab);
    for (let i = 0; i < 4; ++i) {
      WriteToTypedArray(taWrite, i, i);
    }

    // Orig. array: [0, 1, 2, 3]
    //              [0, 1, 2, 3] << fixedLength
    //                    [2, 3] << fixedLengthWithOffset
    //              [0, 1, 2, 3, ...] << lengthTracking
    //                    [2, 3, ...] << lengthTrackingWithOffset

    helper(fixedLength, 0, 2);
    assertEquals([2, 3, 2, 3], ToNumbers(fixedLength));

    for (let i = 0; i < 4; ++i) {
      WriteToTypedArray(taWrite, i, i);
    }

    helper(fixedLengthWithOffset, 0, 1);
    assertEquals([3, 3], ToNumbers(fixedLengthWithOffset));

    for (let i = 0; i < 4; ++i) {
      WriteToTypedArray(taWrite, i, i);
    }

    helper(lengthTracking, 0, 2);
    assertEquals([2, 3, 2, 3], ToNumbers(lengthTracking));

    helper(lengthTrackingWithOffset, 0, 1);
    assertEquals([3, 3], ToNumbers(lengthTrackingWithOffset));

    // Shrink so that fixed length TAs go out of bounds.
    rab.resize(3 * ctor.BYTES_PER_ELEMENT);
    for (let i = 0; i < 3; ++i) {
      WriteToTypedArray(taWrite, i, i);
    }

    // Orig. array: [0, 1, 2]
    //              [0, 1, 2, ...] << lengthTracking
    //                    [2, ...] << lengthTrackingWithOffset

    if (oobThrows) {
      assertThrows(() => { helper(fixedLength, 0, 1); });
      assertThrows(() => { helper(fixedLengthWithOffset, 0, 1); });
    } else {
      helper(fixedLength, 0, 1);
      helper(fixedLengthWithOffset, 0, 1);
      // We'll check below that these were no-op.