1// Copyright (c) 2008 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#include "base/rand_util.h" 6 7#include <limits> 8 9#include "testing/gtest/include/gtest/gtest.h" 10 11namespace { 12 13const int kIntMin = std::numeric_limits<int>::min(); 14const int kIntMax = std::numeric_limits<int>::max(); 15 16} // namespace 17 18TEST(RandUtilTest, SameMinAndMax) { 19 EXPECT_EQ(base::RandInt(0, 0), 0); 20 EXPECT_EQ(base::RandInt(kIntMin, kIntMin), kIntMin); 21 EXPECT_EQ(base::RandInt(kIntMax, kIntMax), kIntMax); 22} 23 24TEST(RandUtilTest, RandDouble) { 25 // Force 64-bit precision, making sure we're not in a 80-bit FPU register. 26 volatile double number = base::RandDouble(); 27 EXPECT_GT(1.0, number); 28 EXPECT_LE(0.0, number); 29} 30 31// Make sure that it is still appropriate to use RandGenerator in conjunction 32// with std::random_shuffle(). 33TEST(RandUtilTest, RandGeneratorForRandomShuffle) { 34 EXPECT_EQ(base::RandGenerator(1), 0U); 35 EXPECT_LE(std::numeric_limits<ptrdiff_t>::max(), 36 std::numeric_limits<int64>::max()); 37} 38