ACK 79e2a276e4817a25c8c8a757dc6ce8e52c1b37f6

Concept ACK

Non-blocking suggestion: Could in-class initialize vsize and weight to reasonable defaults?

The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

Conflicts

Reviewers, this pull request conflicts with the following ones:

• wallet: Introduce SelectionResult for encapsulating a coin selection solution #22019 (wallet: Introduce SelectionResult for encapsulating a coin selection solution by achow101)
• wallet: Cleanup and refactor CreateTransactionInternal #22008 (wallet: Cleanup and refactor CreateTransactionInternal by achow101)
• MOVEONLY: CWallet transaction code out of wallet.cpp/.h #21207 (MOVEONLY: CWallet transaction code out of wallet.cpp/.h by ryanofsky)
• refactor: Make CWalletTx sync state type-safe #21206 (refactor: Make CWalletTx sync state type-safe by ryanofsky)
• Allow fundrawtransaction and walletcreatefundedpsbt to take external inputs #17211 (Allow fundrawtransaction and walletcreatefundedpsbt to take external inputs by achow101)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

utACK 299e85c8188510528f1e49a0b8d2a99f45916898

good changes in git diff 79e2a27 299e85c, modulo clang format nits

rebased on master

review ACK 881a3e2

cr ACK 881a3e2

Much more readable!

Possible candidates for similar treatment (out of scope for this PR of course):

$ git grep -E '^( |std::optional<)*std::pair.*\(' -- "*.h"
src/consensus/tx_verify.h:std::pair<int, int64_t> CalculateSequenceLocks(const CTransaction &tx, int flags, std::vector<int>& prevHeights, const CBlockIndex& block);
src/httpserver.h:    std::pair<bool, std::string> GetHeader(const std::string& hdr) const;
src/indirectmap.h:    std::pair<iterator, bool> insert(const value_type& value) { return m.insert(value); }
src/pubkey.h:    std::optional<std::pair<XOnlyPubKey, bool>> CreateTapTweak(const uint256* merkle_root) const;
src/rpc/util.h:std::pair<int64_t, int64_t> ParseDescriptorRange(const UniValue& value);
src/txorphanage.h:    std::pair<CTransactionRef, NodeId> GetTx(const uint256& txid) const EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans);
src/util/readwritefile.h:std::pair<bool,std::string> ReadBinaryFile(const fs::path &filename, size_t maxsize=std::numeric_limits<size_t>::max());
src/util/system.h:    std::pair<int, char**> get();