refactor: pass BlockCreateOptions to createNewBlock

Rather than pass options individually to createNewBlock and then
combining them into BlockAssembler::Options, this commit introduces
BlockCreateOptions and passes that instead.

Currently there's only one option (use_mempool) but the next
commit adds more.

Co-authored-by: Ryan Ofsky <ryan@ofsky.org>

src/interfaces/mining.h

@@ -5,9 +5,11 @@
 #ifndef BITCOIN_INTERFACES_MINING_H
 #define BITCOIN_INTERFACES_MINING_H
 
+#include <node/types.h>
+#include <uint256.h>
+
 #include <memory>
 #include <optional>
-#include <uint256.h>
 
 namespace node {
 struct CBlockTemplate;
@@ -41,10 +43,10 @@ public:
      * Construct a new block template
      *
      * @param[in] script_pub_key the coinbase output
-     * @param[in] use_mempool set false to omit mempool transactions
+     * @param[in] options options for creating the block
      * @returns a block template
      */
-    virtual std::unique_ptr<node::CBlockTemplate> createNewBlock(const CScript& script_pub_key, bool use_mempool = true) = 0;
+    virtual std::unique_ptr<node::CBlockTemplate> createNewBlock(const CScript& script_pub_key, const node::BlockCreateOptions& options={}) = 0;
 
     /**
      * Processes new block. A valid new block is automatically relayed to peers.

src/node/interfaces.cpp

@@ -884,12 +884,11 @@ public:
         return TestBlockValidity(state, chainman().GetParams(), chainman().ActiveChainstate(), block, tip, /*fCheckPOW=*/false, check_merkle_root);
     }
 
-    std::unique_ptr<CBlockTemplate> createNewBlock(const CScript& script_pub_key, bool use_mempool) override
+    std::unique_ptr<CBlockTemplate> createNewBlock(const CScript& script_pub_key, const BlockCreateOptions& options) override
     {
-        BlockAssembler::Options options;
-        ApplyArgsManOptions(gArgs, options);
-
-        return BlockAssembler{chainman().ActiveChainstate(), use_mempool ? context()->mempool.get() : nullptr, options}.CreateNewBlock(script_pub_key);
+        BlockAssembler::Options assemble_options{options};
+        ApplyArgsManOptions(*Assert(m_node.args), assemble_options);
+        return BlockAssembler{chainman().ActiveChainstate(), context()->mempool.get(), assemble_options}.CreateNewBlock(script_pub_key);
     }
 
     NodeContext* context() override { return &m_node; }

src/node/miner.cpp

@@ -66,7 +66,7 @@ static BlockAssembler::Options ClampOptions(BlockAssembler::Options options)
 
 BlockAssembler::BlockAssembler(Chainstate& chainstate, const CTxMemPool* mempool, const Options& options)
     : chainparams{chainstate.m_chainman.GetParams()},
-      m_mempool{mempool},
+      m_mempool{options.use_mempool ? mempool : nullptr},
       m_chainstate{chainstate},
       m_options{ClampOptions(options)}
 {

src/node/miner.h

@@ -6,6 +6,7 @@
 #ifndef BITCOIN_NODE_MINER_H
 #define BITCOIN_NODE_MINER_H
 
+#include <node/types.h>
 #include <policy/policy.h>
 #include <primitives/block.h>
 #include <txmempool.h>
@@ -153,7 +154,7 @@ private:
     Chainstate& m_chainstate;
 
 public:
-    struct Options {
+    struct Options : BlockCreateOptions {
         // Configuration parameters for the block size
         size_t nBlockMaxWeight{DEFAULT_BLOCK_MAX_WEIGHT};
         CFeeRate blockMinFeeRate{DEFAULT_BLOCK_MIN_TX_FEE};

src/node/types.h

@@ -13,6 +13,8 @@
 #ifndef BITCOIN_NODE_TYPES_H
 #define BITCOIN_NODE_TYPES_H
 
+#include <cstddef>
+
 namespace node {
 enum class TransactionError {
     OK, //!< No error
@@ -24,6 +26,13 @@ enum class TransactionError {
     MAX_BURN_EXCEEDED,
     INVALID_PACKAGE,
 };
+
+struct BlockCreateOptions {
+    /**
+     * Set false to omit mempool transactions
+     */
+    bool use_mempool{true};
+};
 } // namespace node
 
 #endif // BITCOIN_NODE_TYPES_H

src/rpc/mining.cpp

@@ -371,7 +371,7 @@ static RPCHelpMan generateblock()
 
     ChainstateManager& chainman = EnsureChainman(node);
     {
-        std::unique_ptr<CBlockTemplate> blocktemplate{miner.createNewBlock(coinbase_script, /*use_mempool=*/false)};
+        std::unique_ptr<CBlockTemplate> blocktemplate{miner.createNewBlock(coinbase_script, {.use_mempool = false})};
         if (!blocktemplate) {
             throw JSONRPCError(RPC_INTERNAL_ERROR, "Couldn't create new block");
         }