Merge bitcoin/bitcoin#22084: package testmempoolaccept followups

ee862d6efb4c3c01e55f0d5d7a82cce75323cf40 MOVEONLY: context-free package policies (glozow)
5cac95cd15da04b83afa1d31a43be9f5b30a1827 disallow_mempool_conflicts -> allow_bip125_replacement and check earlier (glozow)
e8ecc621be6afd3252c0f8147e42c3b4918f7f46 [refactor] comment/naming improvements (glozow)
7d91442461776e2ef240d7885f768b624de341a7 [rpc] reserve space in txns (glozow)
6c5f19d9c4d267c54f4dbc4f9d65370ff1e0625b [package] static_assert max package size >= max tx size (glozow)

Pull request description:

  various followups from #20833

ACKs for top commit:
  jnewbery:
    utACK ee862d6efb4c3c01e55f0d5d7a82cce75323cf40
  ariard:
    Code Review ACK ee862d6

Tree-SHA512: 96ecb41f7bbced84d4253070f5274b7267607bfe4033e2bb0d2f55ec778cc41e811130b6321131e0418b5835894e510a4be8a0f822bc9d68d9224418359ac837

1 files changed, 13 insertions, 7 deletions

diff --git a/src/validation.h b/src/validation.h
index 359a6c779f..0c396c92ee 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -234,11 +234,13 @@ MempoolAcceptResult AcceptToMemoryPool(CChainState& active_chainstate, CTxMemPoo
                                        bool bypass_limits, bool test_accept=false) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 /**
-* Atomically test acceptance of a package. If the package only contains one tx, package rules still apply.
+* Atomically test acceptance of a package. If the package only contains one tx, package rules still
+* apply. Package validation does not allow BIP125 replacements, so the transaction(s) cannot spend
+* the same inputs as any transaction in the mempool.
 * @param[in]    txns                Group of transactions which may be independent or contain
-*                                   parent-child dependencies. The transactions must not conflict, i.e.
-*                                   must not spend the same inputs, even if it would be a valid BIP125
-*                                   replace-by-fee. Parents must appear before children.
+*                                   parent-child dependencies. The transactions must not conflict
+*                                   with each other, i.e., must not spend the same inputs. If any
+*                                   dependencies exist, parents must appear before children.
 * @returns a PackageMempoolAcceptResult which includes a MempoolAcceptResult for each transaction.
 * If a transaction fails, validation will exit early and some results may be missing.
 */
@@ -269,9 +271,13 @@ bool TestLockPointValidity(CChain& active_chain, const LockPoints* lp) EXCLUSIVE
  * Check if transaction will be BIP68 final in the next block to be created on top of tip.
  * @param[in]   tip             Chain tip to check tx sequence locks against. For example,
  *                              the tip of the current active chain.
- * @param[in]   coins_view      Any CCoinsView that provides access to the relevant coins
- *                              for checking sequence locks. Any CCoinsView can be passed in;
- *                              it is assumed to be consistent with the tip.
+ * @param[in]   coins_view      Any CCoinsView that provides access to the relevant coins for
+ *                              checking sequence locks. For example, it can be a CCoinsViewCache
+ *                              that isn't connected to anything but contains all the relevant
+ *                              coins, or a CCoinsViewMemPool that is connected to the
+ *                              mempool and chainstate UTXO set. In the latter case, the caller is
+ *                              responsible for holding the appropriate locks to ensure that
+ *                              calls to GetCoin() return correct coins.
  * Simulates calling SequenceLocks() with data from the tip passed in.
  * Optionally stores in LockPoints the resulting height and time calculated and the hash
  * of the block needed for calculation or skips the calculation and uses the LockPoints