src/v8/test/unittests/base/utils/random-number-generator-unittest.cc

// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <climits>

#include "src/base/utils/random-number-generator.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace v8 {
namespace base {

class RandomNumberGeneratorTest : public ::testing::TestWithParam<int> {};


static const int kMaxRuns = 12345;


TEST_P(RandomNumberGeneratorTest, NextIntWithMaxValue) {
  RandomNumberGenerator rng(GetParam());
  for (int max = 1; max <= kMaxRuns; ++max) {
    int n = rng.NextInt(max);
    EXPECT_LE(0, n);
    EXPECT_LT(n, max);
  }
}


TEST_P(RandomNumberGeneratorTest, NextBooleanReturnsFalseOrTrue) {
  RandomNumberGenerator rng(GetParam());
  for (int k = 0; k < kMaxRuns; ++k) {
    bool b = rng.NextBool();
    EXPECT_TRUE(b == false || b == true);
  }
}


TEST_P(RandomNumberGeneratorTest, NextDoubleReturnsValueBetween0And1) {
  RandomNumberGenerator rng(GetParam());
  for (int k = 0; k < kMaxRuns; ++k) {
    double d = rng.NextDouble();
    EXPECT_LE(0.0, d);
    EXPECT_LT(d, 1.0);
  }
}


INSTANTIATE_TEST_CASE_P(RandomSeeds, RandomNumberGeneratorTest,
                        ::testing::Values(INT_MIN, -1, 0, 1, 42, 100,
                                          1234567890, 987654321, INT_MAX));

}  // namespace base
}  // namespace v8