Bitcoin ABC  0.26.3
P2P Digital Currency
eda_tests.cpp
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1 // Copyright (c) 2015-2019 The Bitcoin Core developers
2 // Distributed under the MIT/X11 software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 
5 #include <pow/eda.h>
6 #include <pow/pow.h>
7 
8 #include <chain.h>
9 #include <chainparams.h>
10 #include <config.h>
11 
12 #include <test/util/random.h>
13 #include <test/util/setup_common.h>
14 
15 #include <boost/test/unit_test.hpp>
16 
17 BOOST_FIXTURE_TEST_SUITE(eda_tests, BasicTestingSetup)
18 
19 /* Test calculation of next difficulty target with no constraints applying */
20 BOOST_AUTO_TEST_CASE(get_next_work) {
21  DummyConfig config(CBaseChainParams::MAIN);
22 
23  int64_t nLastRetargetTime = 1261130161; // Block #30240
24  CBlockIndex pindexLast;
25  pindexLast.nHeight = 32255;
26  pindexLast.nTime = 1262152739; // Block #32255
27  pindexLast.nBits = 0x1d00ffff;
28 
29  // Here (and below): expected_nbits is calculated in
30  // CalculateNextWorkRequired(); redoing the calculation here would be just
31  // reimplementing the same code that is written in pow.cpp. Rather than
32  // copy that code, we just hardcode the expected result.
33  unsigned int expected_nbits = 0x1d00d86aU;
34  auto consensus_params = config.GetChainParams().GetConsensus();
35  BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime,
36  consensus_params),
37  expected_nbits);
39  PermittedDifficultyTransition(consensus_params, pindexLast.nHeight + 1,
40  pindexLast.nBits, expected_nbits));
41 }
42 
43 /* Test the constraint on the upper bound for next work */
44 BOOST_AUTO_TEST_CASE(get_next_work_pow_limit) {
45  DummyConfig config(CBaseChainParams::MAIN);
46 
47  int64_t nLastRetargetTime = 1231006505; // Block #0
48  CBlockIndex pindexLast;
49  pindexLast.nHeight = 2015;
50  pindexLast.nTime = 1233061996; // Block #2015
51  pindexLast.nBits = 0x1d00ffff;
52  unsigned int expected_nbits = 0x1d00ffffU;
53  auto consensus_params = config.GetChainParams().GetConsensus();
54  BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime,
55  consensus_params),
56  expected_nbits);
58  PermittedDifficultyTransition(consensus_params, pindexLast.nHeight + 1,
59  pindexLast.nBits, expected_nbits));
60 }
61 
62 /* Test the constraint on the lower bound for actual time taken */
63 BOOST_AUTO_TEST_CASE(get_next_work_lower_limit_actual) {
64  DummyConfig config(CBaseChainParams::MAIN);
65 
66  int64_t nLastRetargetTime = 1279008237; // Block #66528
67  CBlockIndex pindexLast;
68  pindexLast.nHeight = 68543;
69  pindexLast.nTime = 1279297671; // Block #68543
70  pindexLast.nBits = 0x1c05a3f4;
71  unsigned int expected_nbits = 0x1c0168fdU;
72  auto consensus_params = config.GetChainParams().GetConsensus();
73  BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime,
74  consensus_params),
75  expected_nbits);
77  PermittedDifficultyTransition(consensus_params, pindexLast.nHeight + 1,
78  pindexLast.nBits, expected_nbits));
79  // Test that reducing nbits further would not be a
80  // PermittedDifficultyTransition.
81  unsigned int invalid_nbits = expected_nbits - 1;
83  !PermittedDifficultyTransition(consensus_params, pindexLast.nHeight + 1,
84  pindexLast.nBits, invalid_nbits));
85 }
86 
87 /* Test the constraint on the upper bound for actual time taken */
88 BOOST_AUTO_TEST_CASE(get_next_work_upper_limit_actual) {
89  DummyConfig config(CBaseChainParams::MAIN);
90 
91  int64_t nLastRetargetTime = 1263163443; // NOTE: Not an actual block time
92  CBlockIndex pindexLast;
93  pindexLast.nHeight = 46367;
94  pindexLast.nTime = 1269211443; // Block #46367
95  pindexLast.nBits = 0x1c387f6f;
96  unsigned int expected_nbits = 0x1d00e1fdU;
97  auto consensus_params = config.GetChainParams().GetConsensus();
98  BOOST_CHECK_EQUAL(CalculateNextWorkRequired(&pindexLast, nLastRetargetTime,
99  consensus_params),
100  expected_nbits);
101  BOOST_CHECK(
102  PermittedDifficultyTransition(consensus_params, pindexLast.nHeight + 1,
103  pindexLast.nBits, expected_nbits));
104  // Test that increasing nbits further would not be a
105  // PermittedDifficultyTransition.
106  unsigned int invalid_nbits = expected_nbits + 1;
107  BOOST_CHECK(
108  !PermittedDifficultyTransition(consensus_params, pindexLast.nHeight + 1,
109  pindexLast.nBits, invalid_nbits));
110 }
111 
112 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_negative_target) {
113  const auto consensus =
114  CreateChainParams(*m_node.args, CBaseChainParams::MAIN)->GetConsensus();
115  BlockHash hash;
116  unsigned int nBits;
117  nBits = UintToArith256(consensus.powLimit).GetCompact(true);
118  hash.SetHex("0x1");
119  BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus));
120 }
121 
122 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_overflow_target) {
123  const auto consensus =
124  CreateChainParams(*m_node.args, CBaseChainParams::MAIN)->GetConsensus();
125  BlockHash hash;
126  unsigned int nBits = ~0x00800000;
127  hash.SetHex("0x1");
128  BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus));
129 }
130 
131 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_too_easy_target) {
132  const auto consensus =
133  CreateChainParams(*m_node.args, CBaseChainParams::MAIN)->GetConsensus();
134  BlockHash hash;
135  unsigned int nBits;
136  arith_uint256 nBits_arith = UintToArith256(consensus.powLimit);
137  nBits_arith *= 2;
138  nBits = nBits_arith.GetCompact();
139  hash.SetHex("0x1");
140  BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus));
141 }
142 
143 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_biger_hash_than_target) {
144  const auto consensus =
145  CreateChainParams(*m_node.args, CBaseChainParams::MAIN)->GetConsensus();
146  BlockHash hash;
147  unsigned int nBits;
148  arith_uint256 hash_arith = UintToArith256(consensus.powLimit);
149  nBits = hash_arith.GetCompact();
150  hash_arith *= 2; // hash > nBits
151  hash = BlockHash(ArithToUint256(hash_arith));
152  BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus));
153 }
154 
155 BOOST_AUTO_TEST_CASE(CheckProofOfWork_test_zero_target) {
156  const auto consensus =
157  CreateChainParams(*m_node.args, CBaseChainParams::MAIN)->GetConsensus();
158  BlockHash hash;
159  unsigned int nBits;
160  arith_uint256 hash_arith{0};
161  nBits = hash_arith.GetCompact();
162  hash = BlockHash(ArithToUint256(hash_arith));
163  BOOST_CHECK(!CheckProofOfWork(hash, nBits, consensus));
164 }
165 
166 BOOST_AUTO_TEST_CASE(GetBlockProofEquivalentTime_test) {
167  DummyConfig config(CBaseChainParams::MAIN);
168 
169  std::vector<CBlockIndex> blocks(10000);
170  for (int i = 0; i < 10000; i++) {
171  blocks[i].pprev = i ? &blocks[i - 1] : nullptr;
172  blocks[i].nHeight = i;
173  blocks[i].nTime =
174  1269211443 +
175  i * config.GetChainParams().GetConsensus().nPowTargetSpacing;
176  blocks[i].nBits = 0x207fffff; /* target 0x7fffff000... */
177  blocks[i].nChainWork =
178  i ? blocks[i - 1].nChainWork + GetBlockProof(blocks[i])
179  : arith_uint256(0);
180  }
181 
182  for (int j = 0; j < 1000; j++) {
183  CBlockIndex *p1 = &blocks[InsecureRandRange(10000)];
184  CBlockIndex *p2 = &blocks[InsecureRandRange(10000)];
185  CBlockIndex *p3 = &blocks[InsecureRandRange(10000)];
186 
187  int64_t tdiff = GetBlockProofEquivalentTime(
188  *p1, *p2, *p3, config.GetChainParams().GetConsensus());
189  BOOST_CHECK_EQUAL(tdiff, p1->GetBlockTime() - p2->GetBlockTime());
190  }
191 }
192 
193 static CBlockIndex GetBlockIndex(CBlockIndex *pindexPrev, int64_t nTimeInterval,
194  uint32_t nBits) {
195  CBlockIndex block;
196  block.pprev = pindexPrev;
197  block.nHeight = pindexPrev->nHeight + 1;
198  block.nTime = pindexPrev->nTime + nTimeInterval;
199  block.nBits = nBits;
200 
201  block.nChainWork = pindexPrev->nChainWork + GetBlockProof(block);
202  return block;
203 }
204 
205 BOOST_AUTO_TEST_CASE(retargeting_test) {
206  DummyConfig config(CBaseChainParams::MAIN);
207 
208  std::vector<CBlockIndex> blocks(115);
209 
210  const Consensus::Params &params = config.GetChainParams().GetConsensus();
211  const arith_uint256 powLimit = UintToArith256(params.powLimit);
212  arith_uint256 currentPow = powLimit >> 1;
213  uint32_t initialBits = currentPow.GetCompact();
214 
215  // Genesis block.
216  blocks[0] = CBlockIndex();
217  blocks[0].nHeight = 0;
218  blocks[0].nTime = 1269211443;
219  blocks[0].nBits = initialBits;
220 
221  blocks[0].nChainWork = GetBlockProof(blocks[0]);
222 
223  // Pile up some blocks.
224  for (size_t i = 1; i < 100; i++) {
225  blocks[i] = GetBlockIndex(&blocks[i - 1], params.nPowTargetSpacing,
226  initialBits);
227  }
228 
229  CBlockHeader blkHeaderDummy;
230 
231  // We start getting 2h blocks time. For the first 5 blocks, it doesn't
232  // matter as the MTP is not affected. For the next 5 block, MTP difference
233  // increases but stays below 12h.
234  for (size_t i = 100; i < 110; i++) {
235  blocks[i] = GetBlockIndex(&blocks[i - 1], 2 * 3600, initialBits);
237  GetNextEDAWorkRequired(&blocks[i], &blkHeaderDummy, params),
238  initialBits);
239  }
240 
241  // Now we expect the difficulty to decrease.
242  blocks[110] = GetBlockIndex(&blocks[109], 2 * 3600, initialBits);
243  currentPow.SetCompact(currentPow.GetCompact());
244  currentPow += (currentPow >> 2);
246  GetNextEDAWorkRequired(&blocks[110], &blkHeaderDummy, params),
247  currentPow.GetCompact());
248 
249  // As we continue with 2h blocks, difficulty continue to decrease.
250  blocks[111] =
251  GetBlockIndex(&blocks[110], 2 * 3600, currentPow.GetCompact());
252  currentPow.SetCompact(currentPow.GetCompact());
253  currentPow += (currentPow >> 2);
255  GetNextEDAWorkRequired(&blocks[111], &blkHeaderDummy, params),
256  currentPow.GetCompact());
257 
258  // We decrease again.
259  blocks[112] =
260  GetBlockIndex(&blocks[111], 2 * 3600, currentPow.GetCompact());
261  currentPow.SetCompact(currentPow.GetCompact());
262  currentPow += (currentPow >> 2);
264  GetNextEDAWorkRequired(&blocks[112], &blkHeaderDummy, params),
265  currentPow.GetCompact());
266 
267  // We check that we do not go below the minimal difficulty.
268  blocks[113] =
269  GetBlockIndex(&blocks[112], 2 * 3600, currentPow.GetCompact());
270  currentPow.SetCompact(currentPow.GetCompact());
271  currentPow += (currentPow >> 2);
272  BOOST_CHECK(powLimit.GetCompact() != currentPow.GetCompact());
274  GetNextEDAWorkRequired(&blocks[113], &blkHeaderDummy, params),
275  powLimit.GetCompact());
276 
277  // Once we reached the minimal difficulty, we stick with it.
278  blocks[114] = GetBlockIndex(&blocks[113], 2 * 3600, powLimit.GetCompact());
279  BOOST_CHECK(powLimit.GetCompact() != currentPow.GetCompact());
281  GetNextEDAWorkRequired(&blocks[114], &blkHeaderDummy, params),
282  powLimit.GetCompact());
283 }
284 
arith_uint256 UintToArith256(const uint256 &a)
uint256 ArithToUint256(const arith_uint256 &a)
arith_uint256 GetBlockProof(const CBlockIndex &block)
Definition: chain.cpp:74
int64_t GetBlockProofEquivalentTime(const CBlockIndex &to, const CBlockIndex &from, const CBlockIndex &tip, const Consensus::Params &params)
Return the time it would take to redo the work difference between from and to, assuming the current h...
Definition: chain.cpp:89
std::unique_ptr< const CChainParams > CreateChainParams(const ArgsManager &args, const std::string &chain)
Creates and returns a std::unique_ptr<CChainParams> of the chosen chain.
Definition: chainparams.cpp:32
static const std::string MAIN
BIP70 chain name strings (main, test or regtest)
Nodes collect new transactions into a block, hash them into a hash tree, and scan through nonce value...
Definition: block.h:23
The block chain is a tree shaped structure starting with the genesis block at the root,...
Definition: blockindex.h:25
CBlockIndex * pprev
pointer to the index of the predecessor of this block
Definition: blockindex.h:32
arith_uint256 nChainWork
(memory only) Total amount of work (expected number of hashes) in the chain up to and including this ...
Definition: blockindex.h:51
uint32_t nTime
Definition: blockindex.h:92
int64_t GetBlockTime() const
Definition: blockindex.h:180
uint32_t nBits
Definition: blockindex.h:93
int nHeight
height of the entry in the chain. The genesis block has height 0
Definition: blockindex.h:38
256-bit unsigned big integer.
arith_uint256 & SetCompact(uint32_t nCompact, bool *pfNegative=nullptr, bool *pfOverflow=nullptr)
The "compact" format is a representation of a whole number N using an unsigned 32bit number similar t...
uint32_t GetCompact(bool fNegative=false) const
void SetHex(const char *psz)
Definition: uint256.cpp:24
uint32_t GetNextEDAWorkRequired(const CBlockIndex *pindexPrev, const CBlockHeader *pblock, const Consensus::Params &params)
Compute the next required proof of work using the legacy Bitcoin difficulty adjustment + Emergency Di...
Definition: eda.cpp:45
uint32_t CalculateNextWorkRequired(const CBlockIndex *pindexPrev, int64_t nFirstBlockTime, const Consensus::Params &params)
Do difficulty adjustement Satoshi's way.
Definition: eda.cpp:14
BOOST_AUTO_TEST_CASE(get_next_work)
Definition: eda_tests.cpp:20
static CBlockIndex GetBlockIndex(CBlockIndex *pindexPrev, int64_t nTimeInterval, uint32_t nBits)
Definition: eda_tests.cpp:193
NodeContext & m_node
Definition: interfaces.cpp:785
#define BOOST_AUTO_TEST_SUITE_END()
Definition: object.cpp:16
#define BOOST_CHECK_EQUAL(v1, v2)
Definition: object.cpp:18
#define BOOST_CHECK(expr)
Definition: object.cpp:17
bool CheckProofOfWork(const BlockHash &hash, uint32_t nBits, const Consensus::Params &params)
Check whether a block hash satisfies the proof-of-work requirement specified by nBits.
Definition: pow.cpp:91
bool PermittedDifficultyTransition(const Consensus::Params &params, int64_t height, uint32_t old_nbits, uint32_t new_nbits)
Return false if the proof-of-work requirement specified by new_nbits at a given height is not possibl...
Definition: pow.cpp:47
BOOST_FIXTURE_TEST_SUITE(stakingrewards_tests, StakingRewardsActivationTestingSetup) BOOST_AUTO_TEST_CASE(isstakingrewardsactivated)
A BlockHash is a unqiue identifier for a block.
Definition: blockhash.h:13
Parameters that influence chain consensus.
Definition: params.h:34
uint256 powLimit
Proof of work parameters.
Definition: params.h:74
int64_t nPowTargetSpacing
Definition: params.h:78