gecko/mfbt/tests/TestRollingMean.cpp

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/Assertions.h"
#include "mozilla/RollingMean.h"

using mozilla::RollingMean;

class MyClass
{
public:
  uint32_t mValue;

  explicit MyClass(uint32_t aValue = 0) : mValue(aValue) { }

  bool operator==(const MyClass& aOther) const
  {
    return mValue == aOther.mValue;
  }

  MyClass operator+(const MyClass& aOther) const
  {
    return MyClass(mValue + aOther.mValue);
  }

  MyClass operator-(const MyClass& aOther) const
  {
    return MyClass(mValue - aOther.mValue);
  }

  MyClass operator/(uint32_t aDiv) const
  {
    return MyClass(mValue / aDiv);
  }
};

class RollingMeanSuite
{
public:
  RollingMeanSuite() { }

  void runTests() {
    testZero();
    testClear();
    testRolling();
    testClass();
    testMove();
  }

private:
  void testZero()
  {
    RollingMean<uint32_t, uint64_t> mean(3);
    MOZ_RELEASE_ASSERT(mean.empty());
  }

  void testClear()
  {
    RollingMean<uint32_t, uint64_t> mean(3);

    mean.insert(4);
    MOZ_RELEASE_ASSERT(mean.mean() == 4);

    mean.clear();
    MOZ_RELEASE_ASSERT(mean.empty());

    mean.insert(3);
    MOZ_RELEASE_ASSERT(mean.mean() == 3);
  }

  void testRolling()
  {
    RollingMean<uint32_t, uint64_t> mean(3);

    mean.insert(10);
    MOZ_RELEASE_ASSERT(mean.mean() == 10);

    mean.insert(20);
    MOZ_RELEASE_ASSERT(mean.mean() == 15);

    mean.insert(35);
    MOZ_RELEASE_ASSERT(mean.mean() == 21);

    mean.insert(5);
    MOZ_RELEASE_ASSERT(mean.mean() == 20);

    mean.insert(10);
    MOZ_RELEASE_ASSERT(mean.mean() == 16);
  }

  void testClass()
  {
    RollingMean<MyClass, MyClass> mean(3);

    mean.insert(MyClass(4));
    MOZ_RELEASE_ASSERT(mean.mean() == MyClass(4));

    mean.clear();
    MOZ_RELEASE_ASSERT(mean.empty());
  }

  void testMove()
  {
    RollingMean<uint32_t, uint64_t> mean(3);
    mean = RollingMean<uint32_t, uint64_t>(4);
    MOZ_RELEASE_ASSERT(mean.maxValues() == 4);

    mean.insert(10);
    MOZ_RELEASE_ASSERT(mean.mean() == 10);

    mean = RollingMean<uint32_t, uint64_t>(3);
    mean.insert(30);
    mean.insert(40);
    mean.insert(50);
    mean.insert(60);
    MOZ_RELEASE_ASSERT(mean.mean() == 50);
  }
};

int
main()
{
  RollingMeanSuite suite;
  suite.runTests();
  return 0;
}