LibTest/typed_data/ByteData/getInt64_A01_t01.dart

// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

/// @assertion
/// int getInt64(
///     int byteOffset, [
///     Endian endian = Endian.big
/// ])
/// Returns the (possibly negative) integer represented by the eight bytes at
/// the specified [byteOffset] in this object, in two's complement binary form.
/// The return value will be between -pow(2, 63) and pow(2, 63) - 1, inclusive.
/// @description Checks that the correct value is returned.
/// @author msyabro


import "dart:typed_data";
import "../../../Utils/expect.dart";

main() {
  var i64 = new Int64List.fromList([
    0, -1, 9223372036854775807, -9223372036854775808, 12, 54, 100, -23, 98,
    23, 43, -15, -3
  ]);
  var u32 = new Uint32List.fromList(
      [0x62e7a17b, 0xf7ec7100, 0xe7180101, 0x1f83ccbb]);
  int bytesInElement = Int64List.bytesPerElement;

  var byteDataFromI64 = new ByteData.view(i64.buffer);
  for (int i = 0; i < byteDataFromI64.lengthInBytes / bytesInElement; ++i) {
    Expect.equals(i64[i],
        byteDataFromI64.getInt64(i * bytesInElement, Endian.little));
  }

  var byteDataFromU32 = new ByteData.view(u32.buffer);
  var expectedBigEndian = [8908655946015829239, 72366452581892895];
  var expectedLittleEndian = [-581966005364350597, 2270883744532922625];
  for (int i = 0; i < byteDataFromU32.lengthInBytes / bytesInElement; ++i) {
    Expect.equals(expectedBigEndian[i],
        byteDataFromU32.getInt64(i * bytesInElement, Endian.big));
    Expect.equals(expectedLittleEndian[i],
        byteDataFromU32.getInt64(i * bytesInElement, Endian.little));
  }
}