Merge #16433: txmempool: Remove unused default value MemPoolRemovalReason::UNKNOWN

0000ff0aa763e3be524ac4537a41048a26529fb2 txmempool: Remove unused default value MemPoolRemovalReason::UNKNOWN (MarcoFalke)

Pull request description:

  The `remove*` methods set the removal reason to `UNKNOWN` by default. This is nowhere used; Except in tests, where the value doesn't matter. Fix that by removing the confusing default.

ACKs for top commit:
  practicalswift:
    utACK 0000ff0aa763e3be524ac4537a41048a26529fb2
  promag:
    ACK 0000ff0aa763e3be524ac4537a41048a26529fb2.
  jonasschnelli:
    utACK 0000ff0aa763e3be524ac4537a41048a26529fb2

Tree-SHA512: ffc8b35dd3291a81225171577c743c8bb2645638cab02960b6361174cb68afd739aaab7ab8661d65de5750d37daf16bb7eee9338958d8609093a8d46c2ada1ab

4 files changed, 17 insertions, 16 deletions

diff --git a/src/test/blockencodings_tests.cpp b/src/test/blockencodings_tests.cpp
index dac201a35f..5ce8e6feb0 100644
--- a/src/test/blockencodings_tests.cpp
+++ b/src/test/blockencodings_tests.cpp
@@ -85,7 +85,7 @@ BOOST_AUTO_TEST_CASE(SimpleRoundTripTest)
         BOOST_CHECK_EQUAL(pool.mapTx.find(block.vtx[2]->GetHash())->GetSharedTx().use_count(), SHARED_TX_OFFSET + 1);
 
         size_t poolSize = pool.size();
-        pool.removeRecursive(*block.vtx[2]);
+        pool.removeRecursive(*block.vtx[2], MemPoolRemovalReason::REPLACED);
         BOOST_CHECK_EQUAL(pool.size(), poolSize - 1);
 
         CBlock block2;
diff --git a/src/test/mempool_tests.cpp b/src/test/mempool_tests.cpp
index c6a3de2285..fe5d31b7d3 100644
--- a/src/test/mempool_tests.cpp
+++ b/src/test/mempool_tests.cpp
@@ -14,6 +14,8 @@
 
 BOOST_FIXTURE_TEST_SUITE(mempool_tests, TestingSetup)
 
+static constexpr auto REMOVAL_REASON_DUMMY = MemPoolRemovalReason::REPLACED;
+
 BOOST_AUTO_TEST_CASE(MempoolRemoveTest)
 {
     // Test CTxMemPool::remove functionality
@@ -59,13 +61,13 @@ BOOST_AUTO_TEST_CASE(MempoolRemoveTest)
 
     // Nothing in pool, remove should do nothing:
     unsigned int poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
 
     // Just the parent:
     testPool.addUnchecked(entry.FromTx(txParent));
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 1);
 
     // Parent, children, grandchildren:
@@ -77,18 +79,18 @@ BOOST_AUTO_TEST_CASE(MempoolRemoveTest)
     }
     // Remove Child[0], GrandChild[0] should be removed:
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txChild[0]));
+    testPool.removeRecursive(CTransaction(txChild[0]), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 2);
     // ... make sure grandchild and child are gone:
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txGrandChild[0]));
+    testPool.removeRecursive(CTransaction(txGrandChild[0]), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txChild[0]));
+    testPool.removeRecursive(CTransaction(txChild[0]), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
     // Remove parent, all children/grandchildren should go:
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 5);
     BOOST_CHECK_EQUAL(testPool.size(), 0U);
 
@@ -101,7 +103,7 @@ BOOST_AUTO_TEST_CASE(MempoolRemoveTest)
     // Now remove the parent, as might happen if a block-re-org occurs but the parent cannot be
     // put into the mempool (maybe because it is non-standard):
     poolSize = testPool.size();
-    testPool.removeRecursive(CTransaction(txParent));
+    testPool.removeRecursive(CTransaction(txParent), REMOVAL_REASON_DUMMY);
     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 6);
     BOOST_CHECK_EQUAL(testPool.size(), 0U);
 }
@@ -283,11 +285,11 @@ BOOST_AUTO_TEST_CASE(MempoolIndexingTest)
     BOOST_CHECK_EQUAL(pool.size(), 10U);
 
     // Now try removing tx10 and verify the sort order returns to normal
-    pool.removeRecursive(pool.mapTx.find(tx10.GetHash())->GetTx());
+    pool.removeRecursive(pool.mapTx.find(tx10.GetHash())->GetTx(), REMOVAL_REASON_DUMMY);
     CheckSort<descendant_score>(pool, snapshotOrder);
 
-    pool.removeRecursive(pool.mapTx.find(tx9.GetHash())->GetTx());
-    pool.removeRecursive(pool.mapTx.find(tx8.GetHash())->GetTx());
+    pool.removeRecursive(pool.mapTx.find(tx9.GetHash())->GetTx(), REMOVAL_REASON_DUMMY);
+    pool.removeRecursive(pool.mapTx.find(tx8.GetHash())->GetTx(), REMOVAL_REASON_DUMMY);
 }
 
 BOOST_AUTO_TEST_CASE(MempoolAncestorIndexingTest)
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index 4bd40687a6..05d7f76983 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -158,7 +158,7 @@ static void TestPackageSelection(const CChainParams& chainparams, const CScript&
     // Test that packages above the min relay fee do get included, even if one
     // of the transactions is below the min relay fee
     // Remove the low fee transaction and replace with a higher fee transaction
-    mempool.removeRecursive(CTransaction(tx));
+    mempool.removeRecursive(CTransaction(tx), MemPoolRemovalReason::REPLACED);
     tx.vout[0].nValue -= 2; // Now we should be just over the min relay fee
     hashLowFeeTx = tx.GetHash();
     mempool.addUnchecked(entry.Fee(feeToUse+2).FromTx(tx));
diff --git a/src/txmempool.h b/src/txmempool.h
index 565dd61f0f..7169e80da2 100644
--- a/src/txmempool.h
+++ b/src/txmempool.h
@@ -345,7 +345,6 @@ struct TxMempoolInfo
  * this is passed to the notification signal.
  */
 enum class MemPoolRemovalReason {
-    UNKNOWN = 0, //!< Manually removed or unknown reason
     EXPIRY,      //!< Expired from mempool
     SIZELIMIT,   //!< Removed in size limiting
     REORG,       //!< Removed for reorganization
@@ -574,7 +573,7 @@ public:
     void addUnchecked(const CTxMemPoolEntry& entry, bool validFeeEstimate = true) EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main);
     void addUnchecked(const CTxMemPoolEntry& entry, setEntries& setAncestors, bool validFeeEstimate = true) EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main);
 
-    void removeRecursive(const CTransaction& tx, MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN) EXCLUSIVE_LOCKS_REQUIRED(cs);
+    void removeRecursive(const CTransaction& tx, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs);
     void removeForReorg(const CCoinsViewCache* pcoins, unsigned int nMemPoolHeight, int flags) EXCLUSIVE_LOCKS_REQUIRED(cs, cs_main);
     void removeConflicts(const CTransaction& tx) EXCLUSIVE_LOCKS_REQUIRED(cs);
     void removeForBlock(const std::vector<CTransactionRef>& vtx, unsigned int nBlockHeight) EXCLUSIVE_LOCKS_REQUIRED(cs);
@@ -613,7 +612,7 @@ public:
      *  Set updateDescendants to true when removing a tx that was in a block, so
      *  that any in-mempool descendants have their ancestor state updated.
      */
-    void RemoveStaged(setEntries &stage, bool updateDescendants, MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN) EXCLUSIVE_LOCKS_REQUIRED(cs);
+    void RemoveStaged(setEntries& stage, bool updateDescendants, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs);
 
     /** When adding transactions from a disconnected block back to the mempool,
      *  new mempool entries may have children in the mempool (which is generally
@@ -735,7 +734,7 @@ private:
      *  transactions in a chain before we've updated all the state for the
      *  removal.
      */
-    void removeUnchecked(txiter entry, MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN) EXCLUSIVE_LOCKS_REQUIRED(cs);
+    void removeUnchecked(txiter entry, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs);
 };
 
 /**