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const gb = 1 * 1024 * 1024 * 1024;
const smallByteLength = 1024;
const largeByteLength = 4 * gb;
// Fast alternative to |assertEq| to avoid a slow VM-call.
// Should only be used when looping over the TypedArray contents to avoid
// unnecessary test slowdowns.
function assertEqNum(e, a) {
if (e !== a) {
assertEq(e, a);
}
}
{
let smallBuffer = new ArrayBuffer(smallByteLength);
let i8 = new Uint8Array(smallBuffer);
for (let i = 0; i < smallByteLength; ++i) {
assertEqNum(i8[i], 0);
i8[i] = i;
}
assertEq(smallBuffer.byteLength, smallByteLength);
assertEq(smallBuffer.detached, false);
// Copy from a small into a large buffer.
let largeBuffer = smallBuffer.transfer(largeByteLength);
assertEq(smallBuffer.byteLength, 0);
assertEq(smallBuffer.detached, true);
assertEq(largeBuffer.byteLength, largeByteLength);
assertEq(largeBuffer.detached, false);
i8 = new Uint8Array(largeBuffer);
for (let i = 0; i < smallByteLength; ++i) {
assertEqNum(i8[i], i & 0xff);
}
// Test the first 100 new bytes.
for (let i = smallByteLength; i < smallByteLength + 100; ++i) {
assertEqNum(i8[i], 0);
}
// And the last 100 new bytes.
for (let i = largeByteLength - 100; i < largeByteLength; ++i) {
assertEqNum(i8[i], 0);
}
// Copy back from a large into a small buffer.
smallBuffer = largeBuffer.transfer(smallByteLength);
assertEq(largeBuffer.byteLength, 0);
assertEq(largeBuffer.detached, true);
assertEq(smallBuffer.byteLength, smallByteLength);
assertEq(smallBuffer.detached, false);
i8 = new Uint8Array(smallBuffer);
for (let i = 0; i < smallByteLength; ++i) {
assertEqNum(i8[i], i & 0xff);
}
}