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 11 namespace { 12 13 const int kIntMin = std::numeric_limits<int>::min(); 14 const int kIntMax = std::numeric_limits<int>::max(); 15 16 } // namespace 17 18 TEST(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 24 TEST(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(). 33 TEST(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