Merge bitcoin/bitcoin#25290: [kernel 3a/n] Decouple `CTxMemPool` from `ArgsManager`

d1684beabe5b738c2cc83de83e1aaef11a761b69 fees: Pass in a filepath instead of referencing gArgs (Carl Dong)
9a3d825c30e8e6118d74a4e568744cb9d03f7f5d init: Remove redundant -*mempool*, -limit* queries (Carl Dong)
6c5c60c4124293d948735756f84efc85262ea66f mempool: Use m_limit for UpdateTransactionsFromBlock (Carl Dong)
9e93b1030182eff92ef91181e17c7dd498c7e164 node/ifaces: Use existing MemPoolLimits (Carl Dong)
38af2bcf358a72b9457d370282e57f4be1c5c849 mempoolaccept: Use limits from mempool in constructor (Carl Dong)
9333427014695ac235c96d48791098168dfdc9db mempool: Introduce (still-unused) MemPoolLimits (Carl Dong)
716bb5fbd31077bbe99d11a54d6c2c250afc8085 scripted-diff: Rename anc/desc size limit vars to indicate SI unit (Carl Dong)
1ecc77321deb61b9f6888e4e10752b9d972fd26e scripted-diff: Rename DEFAULT_MEMPOOL_EXPIRY to indicate time unit (Carl Dong)
aa9141cd8185cb7ad532bc16feb9d302b05d9697 mempool: Pass in -mempoolexpiry instead of referencing gArgs (Carl Dong)
51c7a41a5eb6fcb60333812c770d80227cf7b64d init: Only determine maxmempool once (Carl Dong)
386c9472c8764738282e6d163b42e15a8feda7ea mempool: Make GetMinFee() with custom size protected (Carl Dong)
82f00de7a6a60cbc9ad0c6e1d0ffb1bc70c49af5 mempool: Pass in -maxmempool instead of referencing gArgs (Carl Dong)
f1941e8bfd2eecc478c7660434b1ebf6a64095a0 pool: Add and use MemPoolOptions, ApplyArgsManOptions (Carl Dong)
0199bd35bb44e32ee0db9b51c9d1bd7518c26f19 fuzz/rbf: Add missing TestingSetup (Carl Dong)
ccbaf546a68d6cda8ed3efd0598c0e4121b366bb scripted-diff: Rename DEFAULT_MAX_MEMPOOL_SIZE to indicate SI unit (Carl Dong)
fc02f77ca604f0221171bfde3059b34f5d0fb1cd ArgsMan: Add Get*Arg functions returning optional (Carl Dong)

Pull request description:

  This is part of the `libbitcoinkernel` project: #24303, https://github.com/bitcoin/bitcoin/projects/18

  -----

  As mentioned in the Stage 1 Step 2 description of [the `libbitcoinkernel` project](https://github.com/bitcoin/bitcoin/issues/24303), `ArgsManager` will not be part of `libbitcoinkernel`. Therefore, it is important that we remove any dependence on `ArgsManager` by code that will be part of `libbitcoinkernel`. This is the first in a series of PRs aiming to achieve this.

  This PR removes `CTxMemPool+MempoolAccept`'s dependency on `ArgsManager` by introducing a `CTxMemPool::Options` struct, which is used to specify `CTxMemPool`'s various options at construction time.

  These options are:
  - `-maxmempool` -> `CTxMemPool::Options::max_size`
  - `-mempoolexpiry` -> `CTxMemPool::Options::expiry`
  - `-limitancestorcount` -> `CTxMemPool::Options::limits::ancestor_count`
  - `-limitancestorsize` -> `CTxMemPool::Options::limits::ancestor_size`
  - `-limitdescendantcount` -> `CTxMemPool::Options::limits::descendant_count`
  - `-limitdescendantsize` -> `CTxMemPool::Options::limits::descendant_size`

  More context can be gleaned from the commit messages. The important commits are:

  - 56eb479ded8bfb2ef635bb6f3b484f9d5952c70d "pool: Add and use MemPoolOptions, ApplyArgsManOptions"
  - a1e08b70f3068f4e8def1c630d8f50cd54da7832 "mempool: Pass in -maxmempool instead of referencing gArgs"
  - 6f4bf3ede5812b374828f08fc728ceded2f10024 "mempool: Pass in -mempoolexpiry instead of referencing gArgs"
  - 5958a7fe4806599fc620ee8c1a881ca10fa2dd16 "mempool: Introduce (still-unused) MemPoolLimits"

  Reviewers: Help needed in the following commits (see commit messages):
  - a1e08b70f3068f4e8def1c630d8f50cd54da7832 "mempool: Pass in -maxmempool instead of referencing gArgs"
  - 0695081a797e9a5d7787b78b0f8289dafcc6bff7 "node/ifaces: Use existing MemPoolLimits"

  Note to Reviewers: There are perhaps an infinite number of ways to architect `CTxMemPool::Options`, the current one tries to keep it simple, usable, and flexible. I hope we don't spend too much time arguing over the design here since that's not the point. In the case that you're 100% certain that a different design is strictly better than this one in every regard, please show us a fully-implemented branch.

  -----

  TODO:
  - [x] Use the more ergonomic `CTxMemPool::Options` where appropriate
  - [x] Doxygen comments for `ApplyArgsManOptions`, `MemPoolOptions`

  -----

  Questions for Reviewers:
  1. Should we use `std::chrono::seconds` for `CTxMemPool::Options::expiry` and `CTxMemPool::m_expiry` instead of an `int64_t`? Something else? (`std::chrono::hours`?)
  2. Should I merge `CTxMemPool::Limits` inside `CTxMemPool::Options`?

ACKs for top commit:
  MarcoFalke:
    ACK d1684beabe5b738c2cc83de83e1aaef11a761b69 🍜
  ryanofsky:
    Code review ACK d1684beabe5b738c2cc83de83e1aaef11a761b69. Just minor cleanups since last review, mostly switching to brace initialization

Tree-SHA512: 2c138e52d69f61c263f1c3648f01c801338a8f576762c815f478ef5148b8b2f51e91ded5c1be915e678c0b14f6cfba894b82afec58d999d39a7bb7c914736e0b

2 files changed, 25 insertions, 4 deletions

diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index d9fff85bf5..0c9e880d67 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -14,13 +14,16 @@
 #include <init.h>
 #include <init/common.h>
 #include <interfaces/chain.h>
+#include <mempool_args.h>
 #include <net.h>
 #include <net_processing.h>
 #include <node/blockstorage.h>
 #include <node/chainstate.h>
+#include <node/context.h>
 #include <node/miner.h>
 #include <noui.h>
 #include <policy/fees.h>
+#include <policy/fees_args.h>
 #include <pow.h>
 #include <rpc/blockchain.h>
 #include <rpc/register.h>
@@ -32,6 +35,8 @@
 #include <test/util/net.h>
 #include <timedata.h>
 #include <txdb.h>
+#include <txmempool.h>
+#include <util/designator.h>
 #include <util/strencodings.h>
 #include <util/string.h>
 #include <util/thread.h>
@@ -50,11 +55,12 @@
 
 using node::BlockAssembler;
 using node::CalculateCacheSizes;
+using node::fPruneMode;
+using node::fReindex;
 using node::LoadChainstate;
+using node::NodeContext;
 using node::RegenerateCommitments;
 using node::VerifyLoadedChainstate;
-using node::fPruneMode;
-using node::fReindex;
 
 const std::function<std::string(const char*)> G_TRANSLATION_FUN = nullptr;
 UrlDecodeFn* const URL_DECODE = nullptr;
@@ -149,6 +155,18 @@ BasicTestingSetup::~BasicTestingSetup()
     gArgs.ClearArgs();
 }
 
+CTxMemPool::Options MemPoolOptionsForTest(const NodeContext& node)
+{
+    CTxMemPool::Options mempool_opts{
+        Desig(estimator) node.fee_estimator.get(),
+        // Default to always checking mempool regardless of
+        // chainparams.DefaultConsistencyChecks for tests
+        Desig(check_ratio) 1,
+    };
+    ApplyArgsManOptions(*node.args, mempool_opts);
+    return mempool_opts;
+}
+
 ChainTestingSetup::ChainTestingSetup(const std::string& chainName, const std::vector<const char*>& extra_args)
     : BasicTestingSetup(chainName, extra_args)
 {
@@ -160,8 +178,8 @@ ChainTestingSetup::ChainTestingSetup(const std::string& chainName, const std::ve
     m_node.scheduler->m_service_thread = std::thread(util::TraceThread, "scheduler", [&] { m_node.scheduler->serviceQueue(); });
     GetMainSignals().RegisterBackgroundSignalScheduler(*m_node.scheduler);
 
-    m_node.fee_estimator = std::make_unique<CBlockPolicyEstimator>();
-    m_node.mempool = std::make_unique<CTxMemPool>(m_node.fee_estimator.get(), m_node.args->GetIntArg("-checkmempool", 1));
+    m_node.fee_estimator = std::make_unique<CBlockPolicyEstimator>(FeeestPath(*m_node.args));
+    m_node.mempool = std::make_unique<CTxMemPool>(MemPoolOptionsForTest(m_node));
 
     m_cache_sizes = CalculateCacheSizes(m_args);
 
diff --git a/src/test/util/setup_common.h b/src/test/util/setup_common.h
index 37407bcb92..ed2c5db7e6 100644
--- a/src/test/util/setup_common.h
+++ b/src/test/util/setup_common.h
@@ -90,6 +90,9 @@ struct BasicTestingSetup {
     ArgsManager m_args;
 };
 
+
+CTxMemPool::Options MemPoolOptionsForTest(const node::NodeContext& node);
+
 /** Testing setup that performs all steps up until right before
  * ChainstateManager gets initialized. Meant for testing ChainstateManager
  * initialization behaviour.