Merge #14244: amount: Move CAmount CENT to unit test header

Summary:
fa84723e73 amount: Move CAmount CENT to unit test header (MarcoFalke)

Pull request description:

  `CAmount` is currently not type-safe. Exporting a constant (`CENT`) that is commonly not referred to by that name might be confusing. `CENT` is only used in two places prior to this commit (`ParseMoney` and `MIN_CHANGE`). So replace these with constants relative to `COIN` and move `CENT` to the unit test header.

Tree-SHA512: 5273e96d8664ced6ae211abde2e20bc763e6e99f89404eec02c621f29e1d235e5f9b1ade933743843fae16fc24b643f883deda9221e3d9fd31229d2ab63a914f

Backport of Core [[bitcoin/bitcoin#14244 | PR14244]]

Test Plan:
  ninja check
  ninja check-functional

Reviewers: O1 Bitcoin ABC, #bitcoin_abc, deadalnix

Reviewed By: O1 Bitcoin ABC, #bitcoin_abc, deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D5489

src/amount.h

@@ -151,7 +151,6 @@ struct Amount {
 static constexpr Amount SATOSHI = Amount::satoshi();
 static constexpr Amount CASH = 100 * SATOSHI;
 static constexpr Amount COIN = 100000000 * SATOSHI;
-static constexpr Amount CENT = COIN / 100;
 
 extern const std::string CURRENCY_UNIT;
 

src/bench/ccoins_caching.cpp

@@ -12,8 +12,8 @@
 // FIXME: Dedup with SetupDummyInputs in test/transaction_tests.cpp.
 //
 // Helper: create two dummy transactions, each with
-// two outputs.  The first has 11 and 50 CENT outputs
-// paid to a TX_PUBKEY, the second 21 and 22 CENT outputs
+// two outputs.  The first has 11 and 50 COIN outputs
+// paid to a TX_PUBKEY, the second 21 and 22 COIN outputs
 // paid to a TX_PUBKEYHASH.
 //
 static std::vector<CMutableTransaction>
@@ -30,19 +30,19 @@ SetupDummyInputs(CBasicKeyStore &keystoreRet, CCoinsViewCache &coinsRet) {
 
     // Create some dummy input transactions
     dummyTransactions[0].vout.resize(2);
-    dummyTransactions[0].vout[0].nValue = 11 * CENT;
+    dummyTransactions[0].vout[0].nValue = 11 * COIN;
     dummyTransactions[0].vout[0].scriptPubKey
         << ToByteVector(key[0].GetPubKey()) << OP_CHECKSIG;
-    dummyTransactions[0].vout[1].nValue = 50 * CENT;
+    dummyTransactions[0].vout[1].nValue = 50 * COIN;
     dummyTransactions[0].vout[1].scriptPubKey
         << ToByteVector(key[1].GetPubKey()) << OP_CHECKSIG;
     AddCoins(coinsRet, CTransaction(dummyTransactions[0]), 0);
 
     dummyTransactions[1].vout.resize(2);
-    dummyTransactions[1].vout[0].nValue = 21 * CENT;
+    dummyTransactions[1].vout[0].nValue = 21 * COIN;
     dummyTransactions[1].vout[0].scriptPubKey =
         GetScriptForDestination(key[2].GetPubKey().GetID());
-    dummyTransactions[1].vout[1].nValue = 22 * CENT;
+    dummyTransactions[1].vout[1].nValue = 22 * COIN;
     dummyTransactions[1].vout[1].scriptPubKey =
         GetScriptForDestination(key[3].GetPubKey().GetID());
     AddCoins(coinsRet, CTransaction(dummyTransactions[1]), 0);
@@ -74,7 +74,7 @@ static void CCoinsCaching(benchmark::State &state) {
     t1.vin[2].scriptSig << std::vector<uint8_t>(65, 0)
                         << std::vector<uint8_t>(33, 4);
     t1.vout.resize(2);
-    t1.vout[0].nValue = 90 * CENT;
+    t1.vout[0].nValue = 90 * COIN;
     t1.vout[0].scriptPubKey << OP_1;
 
     // Benchmark.
@@ -84,7 +84,7 @@ static void CCoinsCaching(benchmark::State &state) {
             AreInputsStandard(t, coins, STANDARD_SCRIPT_VERIFY_FLAGS);
         assert(success);
         Amount value = coins.GetValueIn(t);
-        assert(value == (50 + 21 + 22) * CENT);
+        assert(value == (50 + 21 + 22) * COIN);
     }
 }
 

src/bench/rpc_mempool.cpp

@@ -31,9 +31,9 @@ static void RpcMempool(benchmark::State &state) {
         tx.vin[0].scriptSig = CScript() << OP_1;
         tx.vout.resize(1);
         tx.vout[0].scriptPubKey = CScript() << OP_1 << OP_EQUAL;
-        tx.vout[0].nValue = i * CENT;
+        tx.vout[0].nValue = i * COIN;
         const CTransactionRef tx_r{MakeTransactionRef(tx)};
-        AddTx(tx_r, /* fee */ i * CENT, pool);
+        AddTx(tx_r, /* fee */ i * COIN, pool);
     }
 
     while (state.KeepRunning()) {
@@ -57,10 +57,10 @@ static void RpcMempool10k(benchmark::State &state) {
         for (size_t j = 0; j < nOuts; ++j) {
             tx.vin[j].scriptSig = CScript() << OP_1;
             tx.vout[j].scriptPubKey = CScript() << OP_1 << OP_EQUAL;
-            tx.vout[j].nValue = int64_t(i*j) * CENT;
+            tx.vout[j].nValue = int64_t(i*j) * COIN;
         }
         const CTransactionRef tx_r{MakeTransactionRef(tx)};
-        AddTx(tx_r, /* fee */ int64_t(i) * CENT, pool);
+        AddTx(tx_r, /* fee */ int64_t(i) * COIN, pool);
     }
 
     while (state.KeepRunning()) {

src/test/test_bitcoin.h

@@ -57,6 +57,8 @@ static inline bool InsecureRandBool() {
     return g_insecure_rand_ctx.randbool();
 }
 
+static constexpr Amount CENT(COIN / 100);
+
 /**
  * Basic testing setup.
  * This just configures logging and chain parameters.

src/util/moneystr.cpp

@@ -45,7 +45,7 @@ bool ParseMoney(const char *pszIn, Amount &nRet) {
     for (; *p; p++) {
         if (*p == '.') {
             p++;
-            Amount nMult = 10 * CENT;
+            Amount nMult = COIN / 10;
             while (isdigit(*p) && (nMult > Amount::zero())) {
                 nUnits += (*p++ - '0') * nMult;
                 nMult /= 10;

src/wallet/coinselection.h

@@ -10,7 +10,7 @@
 #include <random.h>
 
 //! target minimum change amount
-static constexpr Amount MIN_CHANGE = CENT;
+static constexpr Amount MIN_CHANGE{COIN / 100};
 //! final minimum change amount after paying for fees
 static constexpr Amount MIN_FINAL_CHANGE = MIN_CHANGE / 2;