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
TEST(RandUtilTest,SameMinAndMax)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
TEST(RandUtilTest,RandDouble)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().
TEST(RandUtilTest,RandGeneratorForRandomShuffle)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