1 files changed, 316 insertions, 0 deletions
diff --git a/src/test/versionbits_tests.cpp b/src/test/versionbits_tests.cpp
new file mode 100644
index 0000000000..1f86a06a3f
--- /dev/null
+++ b/src/test/versionbits_tests.cpp
@@ -0,0 +1,316 @@
+// Copyright (c) 2014-2015 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "chain.h"
+#include "random.h"
+#include "versionbits.h"
+#include "test/test_bitcoin.h"
+#include "chainparams.h"
+#include "main.h"
+#include "consensus/params.h"
+
+#include <boost/test/unit_test.hpp>
+
+/* Define a virtual block time, one block per 10 minutes after Nov 14 2014, 0:55:36am */
+int32_t TestTime(int nHeight) { return 1415926536 + 600 * nHeight; }
+
+static const Consensus::Params paramsDummy = Consensus::Params();
+
+class TestConditionChecker : public AbstractThresholdConditionChecker
+{
+private:
+    mutable ThresholdConditionCache cache;
+
+public:
+    int64_t BeginTime(const Consensus::Params& params) const { return TestTime(10000); }
+    int64_t EndTime(const Consensus::Params& params) const { return TestTime(20000); }
+    int Period(const Consensus::Params& params) const { return 1000; }
+    int Threshold(const Consensus::Params& params) const { return 900; }
+    bool Condition(const CBlockIndex* pindex, const Consensus::Params& params) const { return (pindex->nVersion & 0x100); }
+
+    ThresholdState GetStateFor(const CBlockIndex* pindexPrev) const { return AbstractThresholdConditionChecker::GetStateFor(pindexPrev, paramsDummy, cache); }
+};
+
+#define CHECKERS 6
+
+class VersionBitsTester
+{
+    // A fake blockchain
+    std::vector<CBlockIndex*> vpblock;
+
+    // 6 independent checkers for the same bit.
+    // The first one performs all checks, the second only 50%, the third only 25%, etc...
+    // This is to test whether lack of cached information leads to the same results.
+    TestConditionChecker checker[CHECKERS];
+
+    // Test counter (to identify failures)
+    int num;
+
+public:
+    VersionBitsTester() : num(0) {}
+
+    VersionBitsTester& Reset() {
+        for (unsigned int i = 0; i < vpblock.size(); i++) {
+            delete vpblock[i];
+        }
+        for (unsigned int  i = 0; i < CHECKERS; i++) {
+            checker[i] = TestConditionChecker();
+        }
+        vpblock.clear();
+        return *this;
+    }
+
+    ~VersionBitsTester() {
+         Reset();
+    }
+
+    VersionBitsTester& Mine(unsigned int height, int32_t nTime, int32_t nVersion) {
+        while (vpblock.size() < height) {
+            CBlockIndex* pindex = new CBlockIndex();
+            pindex->nHeight = vpblock.size();
+            pindex->pprev = vpblock.size() > 0 ? vpblock.back() : NULL;
+            pindex->nTime = nTime;
+            pindex->nVersion = nVersion;
+            pindex->BuildSkip();
+            vpblock.push_back(pindex);
+        }
+        return *this;
+    }
+
+    VersionBitsTester& TestDefined() {
+        for (int i = 0; i < CHECKERS; i++) {
+            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+                BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_DEFINED, strprintf("Test %i for DEFINED", num));
+            }
+        }
+        num++;
+        return *this;
+    }
+
+    VersionBitsTester& TestStarted() {
+        for (int i = 0; i < CHECKERS; i++) {
+            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+                BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_STARTED, strprintf("Test %i for STARTED", num));
+            }
+        }
+        num++;
+        return *this;
+    }
+
+    VersionBitsTester& TestLockedIn() {
+        for (int i = 0; i < CHECKERS; i++) {
+            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+                BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_LOCKED_IN, strprintf("Test %i for LOCKED_IN", num));
+            }
+        }
+        num++;
+        return *this;
+    }
+
+    VersionBitsTester& TestActive() {
+        for (int i = 0; i < CHECKERS; i++) {
+            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+                BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_ACTIVE, strprintf("Test %i for ACTIVE", num));
+            }
+        }
+        num++;
+        return *this;
+    }
+
+    VersionBitsTester& TestFailed() {
+        for (int i = 0; i < CHECKERS; i++) {
+            if ((insecure_rand() & ((1 << i) - 1)) == 0) {
+                BOOST_CHECK_MESSAGE(checker[i].GetStateFor(vpblock.empty() ? NULL : vpblock.back()) == THRESHOLD_FAILED, strprintf("Test %i for FAILED", num));
+            }
+        }
+        num++;
+        return *this;
+    }
+
+    CBlockIndex * Tip() { return vpblock.size() ? vpblock.back() : NULL; }
+};
+
+BOOST_FIXTURE_TEST_SUITE(versionbits_tests, TestingSetup)
+
+BOOST_AUTO_TEST_CASE(versionbits_test)
+{
+    for (int i = 0; i < 64; i++) {
+        // DEFINED -> FAILED
+        VersionBitsTester().TestDefined()
+                           .Mine(1, TestTime(1), 0x100).TestDefined()
+                           .Mine(11, TestTime(11), 0x100).TestDefined()
+                           .Mine(989, TestTime(989), 0x100).TestDefined()
+                           .Mine(999, TestTime(20000), 0x100).TestDefined()
+                           .Mine(1000, TestTime(20000), 0x100).TestFailed()
+                           .Mine(1999, TestTime(30001), 0x100).TestFailed()
+                           .Mine(2000, TestTime(30002), 0x100).TestFailed()
+                           .Mine(2001, TestTime(30003), 0x100).TestFailed()
+                           .Mine(2999, TestTime(30004), 0x100).TestFailed()
+                           .Mine(3000, TestTime(30005), 0x100).TestFailed()
+
+        // DEFINED -> STARTED -> FAILED
+                           .Reset().TestDefined()
+                           .Mine(1, TestTime(1), 0).TestDefined()
+                           .Mine(1000, TestTime(10000) - 1, 0x100).TestDefined() // One second more and it would be defined
+                           .Mine(2000, TestTime(10000), 0x100).TestStarted() // So that's what happens the next period
+                           .Mine(2051, TestTime(10010), 0).TestStarted() // 51 old blocks
+                           .Mine(2950, TestTime(10020), 0x100).TestStarted() // 899 new blocks
+                           .Mine(3000, TestTime(20000), 0).TestFailed() // 50 old blocks (so 899 out of the past 1000)
+                           .Mine(4000, TestTime(20010), 0x100).TestFailed()
+
+        // DEFINED -> STARTED -> FAILED while threshold reached
+                           .Reset().TestDefined()
+                           .Mine(1, TestTime(1), 0).TestDefined()
+                           .Mine(1000, TestTime(10000) - 1, 0x101).TestDefined() // One second more and it would be defined
+                           .Mine(2000, TestTime(10000), 0x101).TestStarted() // So that's what happens the next period
+                           .Mine(2999, TestTime(30000), 0x100).TestStarted() // 999 new blocks
+                           .Mine(3000, TestTime(30000), 0x100).TestFailed() // 1 new block (so 1000 out of the past 1000 are new)
+                           .Mine(3999, TestTime(30001), 0).TestFailed()
+                           .Mine(4000, TestTime(30002), 0).TestFailed()
+                           .Mine(14333, TestTime(30003), 0).TestFailed()
+                           .Mine(24000, TestTime(40000), 0).TestFailed()
+
+        // DEFINED -> STARTED -> LOCKEDIN at the last minute -> ACTIVE
+                           .Reset().TestDefined()
+                           .Mine(1, TestTime(1), 0).TestDefined()
+                           .Mine(1000, TestTime(10000) - 1, 0x101).TestDefined() // One second more and it would be defined
+                           .Mine(2000, TestTime(10000), 0x101).TestStarted() // So that's what happens the next period
+                           .Mine(2050, TestTime(10010), 0x200).TestStarted() // 50 old blocks
+                           .Mine(2950, TestTime(10020), 0x100).TestStarted() // 900 new blocks
+                           .Mine(2999, TestTime(19999), 0x200).TestStarted() // 49 old blocks
+                           .Mine(3000, TestTime(29999), 0x200).TestLockedIn() // 1 old block (so 900 out of the past 1000)
+                           .Mine(3999, TestTime(30001), 0).TestLockedIn()
+                           .Mine(4000, TestTime(30002), 0).TestActive()
+                           .Mine(14333, TestTime(30003), 0).TestActive()
+                           .Mine(24000, TestTime(40000), 0).TestActive();
+    }
+
+    // Sanity checks of version bit deployments
+    const Consensus::Params &mainnetParams = Params(CBaseChainParams::MAIN).GetConsensus();
+    for (int i=0; i<(int) Consensus::MAX_VERSION_BITS_DEPLOYMENTS; i++) {
+        uint32_t bitmask = VersionBitsMask(mainnetParams, (Consensus::DeploymentPos)i);
+        // Make sure that no deployment tries to set an invalid bit.
+        BOOST_CHECK_EQUAL(bitmask & ~(uint32_t)VERSIONBITS_TOP_MASK, bitmask);
+
+        // Verify that the deployment windows of different deployment using the
+        // same bit are disjoint.
+        // This test may need modification at such time as a new deployment
+        // is proposed that reuses the bit of an activated soft fork, before the
+        // end time of that soft fork.  (Alternatively, the end time of that
+        // activated soft fork could be later changed to be earlier to avoid
+        // overlap.)
+        for (int j=i+1; j<(int) Consensus::MAX_VERSION_BITS_DEPLOYMENTS; j++) {
+            if (VersionBitsMask(mainnetParams, (Consensus::DeploymentPos)j) == bitmask) {
+                BOOST_CHECK(mainnetParams.vDeployments[j].nStartTime > mainnetParams.vDeployments[i].nTimeout ||
+                        mainnetParams.vDeployments[i].nStartTime > mainnetParams.vDeployments[j].nTimeout);
+            }
+        }
+    }
+}
+
+BOOST_AUTO_TEST_CASE(versionbits_computeblockversion)
+{
+    // Check that ComputeBlockVersion will set the appropriate bit correctly
+    // on mainnet.
+    const Consensus::Params &mainnetParams = Params(CBaseChainParams::MAIN).GetConsensus();
+
+    // Use the TESTDUMMY deployment for testing purposes.
+    int64_t bit = mainnetParams.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit;
+    int64_t nStartTime = mainnetParams.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime;
+    int64_t nTimeout = mainnetParams.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout;
+
+    assert(nStartTime < nTimeout);
+
+    // In the first chain, test that the bit is set by CBV until it has failed.
+    // In the second chain, test the bit is set by CBV while STARTED and
+    // LOCKED-IN, and then no longer set while ACTIVE.
+    VersionBitsTester firstChain, secondChain;
+
+    // Start generating blocks before nStartTime
+    int64_t nTime = nStartTime - 1;
+
+    // Before MedianTimePast of the chain has crossed nStartTime, the bit
+    // should not be set.
+    CBlockIndex *lastBlock = NULL;
+    lastBlock = firstChain.Mine(2016, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+    BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit), 0);
+
+    // Mine 2011 more blocks at the old time, and check that CBV isn't setting the bit yet.
+    for (int i=1; i<2012; i++) {
+        lastBlock = firstChain.Mine(2016+i, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+        // This works because VERSIONBITS_LAST_OLD_BLOCK_VERSION happens
+        // to be 4, and the bit we're testing happens to be bit 28.
+        BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit), 0);
+    }
+    // Now mine 5 more blocks at the start time -- MTP should not have passed yet, so
+    // CBV should still not yet set the bit.
+    nTime = nStartTime;
+    for (int i=2012; i<=2016; i++) {
+        lastBlock = firstChain.Mine(2016+i, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+        BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit), 0);
+    }
+
+    // Advance to the next period and transition to STARTED,
+    lastBlock = firstChain.Mine(6048, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+    // so ComputeBlockVersion should now set the bit,
+    BOOST_CHECK((ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit)) != 0);
+    // and should also be using the VERSIONBITS_TOP_BITS.
+    BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & VERSIONBITS_TOP_MASK, VERSIONBITS_TOP_BITS);
+
+    // Check that ComputeBlockVersion will set the bit until nTimeout
+    nTime += 600;
+    int blocksToMine = 4032; // test blocks for up to 2 time periods
+    int nHeight = 6048;
+    // These blocks are all before nTimeout is reached.
+    while (nTime < nTimeout && blocksToMine > 0) {
+        lastBlock = firstChain.Mine(nHeight+1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+        BOOST_CHECK((ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit)) != 0);
+        BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & VERSIONBITS_TOP_MASK, VERSIONBITS_TOP_BITS);
+        blocksToMine--;
+        nTime += 600;
+        nHeight += 1;
+    };
+
+    nTime = nTimeout;
+    // FAILED is only triggered at the end of a period, so CBV should be setting
+    // the bit until the period transition.
+    for (int i=0; i<2015; i++) {
+        lastBlock = firstChain.Mine(nHeight+1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+        BOOST_CHECK((ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit)) != 0);
+        nHeight += 1;
+    }
+    // The next block should trigger no longer setting the bit.
+    lastBlock = firstChain.Mine(nHeight+1, nTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+    BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit), 0);
+
+    // On a new chain:
+    // verify that the bit will be set after lock-in, and then stop being set
+    // after activation.
+    nTime = nStartTime;
+
+    // Mine one period worth of blocks, and check that the bit will be on for the
+    // next period.
+    lastBlock = secondChain.Mine(2016, nStartTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+    BOOST_CHECK((ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit)) != 0);
+
+    // Mine another period worth of blocks, signaling the new bit.
+    lastBlock = secondChain.Mine(4032, nStartTime, VERSIONBITS_TOP_BITS | (1<<bit)).Tip();
+    // After one period of setting the bit on each block, it should have locked in.
+    // We keep setting the bit for one more period though, until activation.
+    BOOST_CHECK((ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit)) != 0);
+
+    // Now check that we keep mining the block until the end of this period, and
+    // then stop at the beginning of the next period.
+    lastBlock = secondChain.Mine(6047, nStartTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+    BOOST_CHECK((ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit)) != 0);
+    lastBlock = secondChain.Mine(6048, nStartTime, VERSIONBITS_LAST_OLD_BLOCK_VERSION).Tip();
+    BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & (1<<bit), 0);
+
+    // Finally, verify that after a soft fork has activated, CBV no longer uses
+    // VERSIONBITS_LAST_OLD_BLOCK_VERSION.
+    //BOOST_CHECK_EQUAL(ComputeBlockVersion(lastBlock, mainnetParams) & VERSIONBITS_TOP_MASK, VERSIONBITS_TOP_BITS);
+}
+
+
+BOOST_AUTO_TEST_SUITE_END()