Merge bitcoin/bitcoin#24152: policy / validation: CPFP fee bumping within packages

9bebf35e269b2a918df27708565ecd0c5bd3f116 [validation] don't package validate if not policy or missing inputs (glozow)
51edcffa0e156dba06191a8d5c636ba01fa5b65f [unit test] package feerate and package cpfp (glozow)
1b93748c937e870e7574a8e120a85bee6f9013ff [validation] try individual validation before package validation (glozow)
17a8ffd8020375d60428695858558f2be264aa36 [packages/policy] use package feerate in package validation (glozow)
09f32cffa6c3e8b2d77281a5983ffe8f482a5945 [docs] package feerate (glozow)

Pull request description:

  Part of #22290, aka [Package Mempool Accept](https://gist.github.com/glozow/dc4e9d5c5b14ade7cdfac40f43adb18a).

  This enables CPFP fee bumping in child-with-unconfirmed-parents packages by introducing [package feerate](https://gist.github.com/glozow/dc4e9d5c5b14ade7cdfac40f43adb18a#fee-related-checks-use-package-feerate) (total modified fees divided by total virtual size) and using it in place of individual feerate. We also always [validate individual transactions first](https://gist.github.com/glozow/dc4e9d5c5b14ade7cdfac40f43adb18a#always-try-individual-submission-first) to avoid incentive-incompatible policies like "parents pay for children" or "siblings pay for siblings" behavior.

ACKs for top commit:
  instagibbs:
    reACK https://github.com/bitcoin/bitcoin/pull/24152/commits/9bebf35e269b2a918df27708565ecd0c5bd3f116
  mzumsande:
    Code review ACK 9bebf35e269b2a918df27708565ecd0c5bd3f116
  t-bast:
    ACK https://github.com/bitcoin/bitcoin/pull/24152/commits/9bebf35e269b2a918df27708565ecd0c5bd3f116

Tree-SHA512: 5117cfcc3ce55c00384d9e8003a0589ceac1e6f738b1c299007d9cd9cdd2d7c530d31cfd23658b041a6604d39073bcc6e81f0639a300082a92097682a6ea8c8f

1 files changed, 9 insertions, 5 deletions

diff --git a/src/test/fuzz/tx_pool.cpp b/src/test/fuzz/tx_pool.cpp
index df5b271d06..f686f4fd86 100644
--- a/src/test/fuzz/tx_pool.cpp
+++ b/src/test/fuzz/tx_pool.cpp
@@ -234,14 +234,18 @@ FUZZ_TARGET_INIT(tx_pool_standard, initialize_tx_pool)
         const bool bypass_limits = fuzzed_data_provider.ConsumeBool();
         ::fRequireStandard = fuzzed_data_provider.ConsumeBool();
 
-        // Make sure ProcessNewPackage on one transaction works and always fully validates the transaction.
+        // Make sure ProcessNewPackage on one transaction works.
         // The result is not guaranteed to be the same as what is returned by ATMP.
         const auto result_package = WITH_LOCK(::cs_main,
                                     return ProcessNewPackage(chainstate, tx_pool, {tx}, true));
-        auto it = result_package.m_tx_results.find(tx->GetWitnessHash());
-        Assert(it != result_package.m_tx_results.end());
-        Assert(it->second.m_result_type == MempoolAcceptResult::ResultType::VALID ||
-               it->second.m_result_type == MempoolAcceptResult::ResultType::INVALID);
+        // If something went wrong due to a package-specific policy, it might not return a
+        // validation result for the transaction.
+        if (result_package.m_state.GetResult() != PackageValidationResult::PCKG_POLICY) {
+            auto it = result_package.m_tx_results.find(tx->GetWitnessHash());
+            Assert(it != result_package.m_tx_results.end());
+            Assert(it->second.m_result_type == MempoolAcceptResult::ResultType::VALID ||
+                   it->second.m_result_type == MempoolAcceptResult::ResultType::INVALID);
+        }
 
         const auto res = WITH_LOCK(::cs_main, return AcceptToMemoryPool(chainstate, tx, GetTime(), bypass_limits, /*test_accept=*/false));
         const bool accepted = res.m_result_type == MempoolAcceptResult::ResultType::VALID;