This is required for removing the UniValue copy constructor.
-BEGIN VERIFY SCRIPT-
sed -i 's/return NullUniValue/return UniValue::VNULL/g' $(git grep -l NullUniValue ':(exclude)src/univalue')
-END VERIFY SCRIPT-
Seeking to make the `CoinControl` option less confusing/redundant.
In #16377 the `CoinControl` flag ‘m_add_inputs’ was added to tell the coin filtering and selection process two things:
- Coin Filtering: Only use the provided inputs. Skip the Rest.
- Coin Selection: Search the wtxs-outputs and append all the `CoinControl` selected outpoints to the selection result (skipping all the available output checks). Nothing else.
Meanwhile, in `CoinControl` we already have a flag ‘fAllowOtherInputs’ which is already saying:
- Coin Filtering: Only use the provided inputs. Skip the Rest.
- Coin Selection: If false, no selection process -> append all the `CoinControl` selected outpoints to the selection result (while they passed all the `AvailableCoins` checks and are available in the 'vCoins' vector).
As can notice, the first point in the coin filtering process is duplicated in the two option flags. And the second one, is slightly different merely because it takes into account whether the coin is on the `AvailableCoins` vector or not.
So it makes sense to merge ‘m_add_inputs’ and ‘fAllowOtherInputs’ into a single field for the coin filtering process while introduce other changes to add the missing/skipped coins into 'vCoins' vector if they were manually selected by the user (follow-up commits).
fd5c996d16 wallet: GetAvailableBalance, remove double walk-through every available coin (furszy)
162d4ad10f wallet: add 'only_spendable' filter to AvailableCoins (furszy)
cdf185ccfb wallet: remove unused IsSpentKey(hash, index) method (furszy)
4b83bf8dbc wallet: avoid extra IsSpentKey -> GetWalletTx lookups (furszy)
3d8a282257 wallet: decouple IsSpentKey(scriptPubKey) from IsSpentKey(hash, n) (furszy)
a06fa94ff8 wallet: IsSpent, 'COutPoint' arg instead of (hash, index) (furszy)
91902b7720 wallet: IsLockedCoin, 'COutPoint' arg instead of (hash, index) (furszy)
9472ca0a65 wallet: AvailableCoins, don't call 'wtx.tx->vout[i]' multiple times (furszy)
4ce235ef8f wallet: return 'CoinsResult' struct in `AvailableCoins` (furszy)
Pull request description:
This started in #24845 but grew out of scope of it.
So, points tackled:
1) Avoid extra `GetWalletTx` lookups inside `AvailableCoins -> IsSpentKey`.
`IsSpentKey` was receiving the tx hash and index to internally lookup the tx inside the wallet's map. As all the `IsSpentKey` function callers already have the wtx available, them can provide the `scriptPubKey` directly.
2) Most of the time, we call `Wallet::AvailableCoins`, and later on the process, skip the non-spendable coins from the result in subsequent for-loops. So to speedup the process: introduced the ability to filter by "only_spendable" coins inside `Wallet::AvailableCoins` directly.
(the non-spendable coins skip examples are inside `AttemptSelection->GroupOutputs` and `GetAvailableBalance`).
4) Refactored `AvailableCoins` in several ways:
a) Now it will return a new struct `CoinsResult` instead of receiving the vCoins vector reference (which was being cleared at the beginning of the method anyway). --> this is coming from #24845 but cherry-picked it here too to make the following commits look nicer.
b) Unified all the 'wtx.tx->vout[I]' calls into a single call (coming from this comment https://github.com/bitcoin/bitcoin/pull/24699#discussion_r854163032).
5) The wallet `IsLockedCoin` and `IsSpent` methods now accept an `OutPoint` instead of a hash:index. Which let me cleanup a bunch of extra code.
6) Speeded up the wallet 'GetAvailableBalance': filtering `AvailableCoins` by spendable outputs only and using the 'AvailableCoins' retrieved `total_amount` instead of looping over all the retrieved coins once more.
-------------------------------------------------------
Side topic, all this process will look even nicer with #25218
ACKs for top commit:
achow101:
ACK fd5c996d16
brunoerg:
crACK fd5c996d16
w0xlt:
Code Review ACK fd5c996d16
Tree-SHA512: 376a85476f907f4f7d1fc3de74b3dbe159b8cc24687374d8739711ad202ea07a33e86f4e66dece836da3ae6985147119fe584f6e672f11d0450ba6bd165b3220
7832e9438f test: fundrawtransaction preset input weight calculation (S3RK)
c3981e379f wallet: do not count wallet utxos as external (S3RK)
Pull request description:
Correctly differentiating between external vs non-external utxos in coin control produces more accurate weight and fee estimations.
Weight for external utxos is estimated based on the maximum signature size, while for the wallet utxos we expect minimal signature due to signature grinding.
ACKs for top commit:
achow101:
re-ACK 7832e9438f
Xekyo:
re-ACK 7832e9438f
furszy:
ACK 7832e943
Tree-SHA512: bb5635b0bd85fa9a76922a53ad3fa062286424c06a695a0e87407c665713e80a33555b644fbb13bcc1ab503dcd7f53aacbdc368d69ac0ecff8005603623ac94f
Instead of accepting a `vCoins` reference that is cleared at the beginning of the method.
Note:
This new struct, down the commits line, will contain other `AvailableCoins` useful results.
Previously in COutput, effective_value was initialized as the absolute
value of the txout, and fee as 0. effective_value along with fee were
calculated outside of the COutput constructor and set after the
object had been initialized. These changes will allow either the fee
or the feerate to be passed in a COutput constructor. If either are
provided, fee and effective_value are calculated and set in the
constructor. As a result, AvailableCoins also needs to be passed the
feerate when utxos are being spent. When balance is calculated or the
coins are being listed and feerate is neither available nor required,
AvailableCoinsListUnspent is used instead, which runs AvailableCoins
while providing the default value for feerate. Unit tests for the
calculation of effective value have also been added.
_Motivation_
Currently, the wallet uses a fSubtractFeeAmount (SFFO) flag on the
recipients objects for all forms of sending calls. According to the
commit discussion, this flag was chiefly introduced to permit sweeping
without manually calculating the fees of transactions. However, the flag
leads to unintuitive behavior and makes it more complicated to test
many wallet RPCs exhaustively. We proposed to introduce a dedicated
`sendall` RPC with the intention to cover this functionality.
Since the proposal, it was discovered in further discussion that our
proposed `sendall` rpc and SFFO have subtly different scopes of
operation.
• sendall:
Use _specific UTXOs_ to pay a destination the remainder after fees.
• SFFO:
Use a _specific budget_ to pay an address the remainder after fees.
While `sendall` will simplify cases of spending from specific UTXOs,
emptying a wallet, or burning dust, we realized that there are some
cases in which SFFO is used to pay other parties from a limited budget,
which can often lead to the creation of change outputs. This cannot be
easily replicated using `sendall` as it would require manual computation
of the appropriate change amount.
As such, sendall cannot replace all uses of SFFO, but it still has a
different use case and will aid in simplifying some wallet calls and
numerous wallet tests.
_Sendall call details_
The proposed sendall call builds a transaction from a specific subset of
the wallet's UTXO pool (by default all of them) and assigns the funds to
one or more receivers. Receivers can either be specified with a specific
amount or receive an equal share of the remaining unassigned funds. At
least one recipient must be provided without assigned amount to collect
the remainder. The `sendall` call will never create change. The call has
a `send_max` option that changes the default behavior of spending all
UTXOs ("no UTXO left behind"), to maximizing the output amount of the
transaction by skipping uneconomic UTXOs. The `send_max` option is
incompatible with providing a specific set of inputs.
The final step of send either produces a PSBT or the final transaction.
We extract these steps to a new helper function `FinishTransaction()` to
reuse them in `sendall`.
Coin selection requires knowing the weight of a transaction so that fees
can be estimated. However for external inputs, the weight may not be
avialble, and solving data may not be enough as the input could be one
that we do not support. By allowing users to specify input weights,
those external inputs can be included in the transaction.
Additionally, if the weight for an input is specified, that value will
always be used, regardless of whether the input is in the wallet or
solving data is available. This allows us to account for scenarios where
the wallet may be more conservative and estimate a larger input than may
actually be created.
For example, we assume the maximum DER signature size, but an external
input may be signed by a wallet which does nonce grinding in order to get
a smaller signature. In that case, the user can specify the smaller
input weight to avoid overpaying transaction fees.
c0405ee27f rpc: Document that DEFAULT is for Taproot, ALL for everything else (Andrew Chow)
d3992669df psbt: Actually use SIGHASH_DEFAULT (Andrew Chow)
eb9a1a2c59 psbt: Make sighash_type std::optional<int> (Andrew Chow)
Pull request description:
Make the behavior align with the help text by actually using SIGHASH_DEFAULT as the default sighash for signing PSBTs.
ACKs for top commit:
Sjors:
re-utACK c0405ee27f
Tree-SHA512: 5199fb41de416b2f10ac451f824e7c94b428ba11fdb9e50f0027c692e959ce5813a340c34a4e52d7aa128e12008303d80939a693eff36a869720e45442119828
