lbrycrd/src/test/mruset_tests.cpp
Wladimir J. van der Laan 3fc6846181 Add licenses for tests and test data
- Add license headers to source files (years based on commit dates)
  in `src/test` as well as `qa`
- Add `README.md` to `src/test/data` specifying MIT license

Fixes #3848
2014-03-18 10:20:55 +01:00

97 lines
2.2 KiB
C++

// Copyright (c) 2012-2013 The Bitcoin Core developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "mruset.h"
#include "util.h"
#include <set>
#include <boost/test/unit_test.hpp>
#define NUM_TESTS 16
#define MAX_SIZE 100
using namespace std;
class mrutester
{
private:
mruset<int> mru;
std::set<int> set;
public:
mrutester() { mru.max_size(MAX_SIZE); }
int size() const { return set.size(); }
void insert(int n)
{
mru.insert(n);
set.insert(n);
BOOST_CHECK(mru == set);
}
};
BOOST_AUTO_TEST_SUITE(mruset_tests)
// Test that an mruset behaves like a set, as long as no more than MAX_SIZE elements are in it
BOOST_AUTO_TEST_CASE(mruset_like_set)
{
for (int nTest=0; nTest<NUM_TESTS; nTest++)
{
mrutester tester;
while (tester.size() < MAX_SIZE)
tester.insert(GetRandInt(2 * MAX_SIZE));
}
}
// Test that an mruset's size never exceeds its max_size
BOOST_AUTO_TEST_CASE(mruset_limited_size)
{
for (int nTest=0; nTest<NUM_TESTS; nTest++)
{
mruset<int> mru(MAX_SIZE);
for (int nAction=0; nAction<3*MAX_SIZE; nAction++)
{
int n = GetRandInt(2 * MAX_SIZE);
mru.insert(n);
BOOST_CHECK(mru.size() <= MAX_SIZE);
}
}
}
// 16-bit permutation function
int static permute(int n)
{
// hexadecimals of pi; verified to be linearly independent
static const int table[16] = {0x243F, 0x6A88, 0x85A3, 0x08D3, 0x1319, 0x8A2E, 0x0370, 0x7344,
0xA409, 0x3822, 0x299F, 0x31D0, 0x082E, 0xFA98, 0xEC4E, 0x6C89};
int ret = 0;
for (int bit=0; bit<16; bit++)
if (n & (1<<bit))
ret ^= table[bit];
return ret;
}
// Test that an mruset acts like a moving window, if no duplicate elements are added
BOOST_AUTO_TEST_CASE(mruset_window)
{
mruset<int> mru(MAX_SIZE);
for (int n=0; n<10*MAX_SIZE; n++)
{
mru.insert(permute(n));
set<int> tester;
for (int m=max(0,n-MAX_SIZE+1); m<=n; m++)
tester.insert(permute(m));
BOOST_CHECK(mru == tester);
}
}
BOOST_AUTO_TEST_SUITE_END()