rustfmt: Run on util/transaction_utils.rs

Author: tnull

lightning/src/util/transaction_utils.rs

@@ -8,23 +8,21 @@
 // licenses.
 
 use bitcoin::amount::Amount;
-use bitcoin::transaction::{Transaction, TxOut};
-use bitcoin::script::ScriptBuf;
-use bitcoin::consensus::Encodable;
 use bitcoin::consensus::encode::VarInt;
+use bitcoin::consensus::Encodable;
+use bitcoin::script::ScriptBuf;
+use bitcoin::transaction::{Transaction, TxOut};
 
 #[allow(unused_imports)]
 use crate::prelude::*;
 
 use crate::io_extras::sink;
 use core::cmp::Ordering;
 
-pub fn sort_outputs<T, C : Fn(&T, &T) -> Ordering>(outputs: &mut Vec<(TxOut, T)>, tie_breaker: C) {
+pub fn sort_outputs<T, C: Fn(&T, &T) -> Ordering>(outputs: &mut Vec<(TxOut, T)>, tie_breaker: C) {
 	outputs.sort_unstable_by(|a, b| {
 		a.0.value.cmp(&b.0.value).then_with(|| {
-			a.0.script_pubkey[..].cmp(&b.0.script_pubkey[..]).then_with(|| {
-				tie_breaker(&a.1, &b.1)
-			})
+			a.0.script_pubkey[..].cmp(&b.0.script_pubkey[..]).then_with(|| tie_breaker(&a.1, &b.1))
 		})
 	});
 }
@@ -34,34 +32,44 @@ pub fn sort_outputs<T, C : Fn(&T, &T) -> Ordering>(outputs: &mut Vec<(TxOut, T)>
 /// Assumes at least one input will have a witness (ie spends a segwit output).
 /// Returns an Err(()) if the requested feerate cannot be met.
 /// Returns the expected maximum weight of the fully signed transaction on success.
-pub(crate) fn maybe_add_change_output(tx: &mut Transaction, input_value: Amount, witness_max_weight: u64, feerate_sat_per_1000_weight: u32, change_destination_script: ScriptBuf) -> Result<u64, ()> {
-	if input_value > Amount::MAX_MONEY { return Err(()); }
+pub(crate) fn maybe_add_change_output(
+	tx: &mut Transaction, input_value: Amount, witness_max_weight: u64,
+	feerate_sat_per_1000_weight: u32, change_destination_script: ScriptBuf,
+) -> Result<u64, ()> {
+	if input_value > Amount::MAX_MONEY {
+		return Err(());
+	}
 
 	const WITNESS_FLAG_BYTES: u64 = 2;
 
 	let mut output_value = Amount::ZERO;
 	for output in tx.output.iter() {
 		output_value += output.value;
-		if output_value >= input_value { return Err(()); }
+		if output_value >= input_value {
+			return Err(());
+		}
 	}
 
 	let dust_value = change_destination_script.minimal_non_dust();
-	let mut change_output = TxOut {
-		script_pubkey: change_destination_script,
-		value: Amount::ZERO,
-	};
+	let mut change_output = TxOut { script_pubkey: change_destination_script, value: Amount::ZERO };
 	let change_len = change_output.consensus_encode(&mut sink()).unwrap();
 	let starting_weight = tx.weight().to_wu() + WITNESS_FLAG_BYTES + witness_max_weight as u64;
 	let mut weight_with_change: i64 = starting_weight as i64 + change_len as i64 * 4;
 	// Include any extra bytes required to push an extra output.
-	weight_with_change += (VarInt(tx.output.len() as u64 + 1).size() - VarInt(tx.output.len() as u64).size()) as i64 * 4;
+	weight_with_change += (VarInt(tx.output.len() as u64 + 1).size()
+		- VarInt(tx.output.len() as u64).size()) as i64
+		* 4;
 	// When calculating weight, add two for the flag bytes
-	let change_value: i64 = (input_value - output_value).to_sat() as i64 - weight_with_change * feerate_sat_per_1000_weight as i64 / 1000;
+	let change_value: i64 = (input_value - output_value).to_sat() as i64
+		- weight_with_change * feerate_sat_per_1000_weight as i64 / 1000;
 	if change_value >= dust_value.to_sat() as i64 {
 		change_output.value = Amount::from_sat(change_value as u64);
 		tx.output.push(change_output);
 		Ok(weight_with_change as u64)
-	} else if (input_value - output_value).to_sat() as i64 - (starting_weight as i64) * feerate_sat_per_1000_weight as i64 / 1000 < 0 {
+	} else if (input_value - output_value).to_sat() as i64
+		- (starting_weight as i64) * feerate_sat_per_1000_weight as i64 / 1000
+		< 0
+	{
 		Err(())
 	} else {
 		Ok(starting_weight)
@@ -73,60 +81,58 @@ mod tests {
 	use super::*;
 
 	use bitcoin::amount::Amount;
-	use bitcoin::locktime::absolute::LockTime;
-	use bitcoin::transaction::{TxIn, OutPoint, Version};
-	use bitcoin::script::Builder;
 	use bitcoin::hash_types::Txid;
 	use bitcoin::hashes::Hash;
 	use bitcoin::hex::FromHex;
+	use bitcoin::locktime::absolute::LockTime;
+	use bitcoin::script::Builder;
+	use bitcoin::transaction::{OutPoint, TxIn, Version};
 	use bitcoin::{PubkeyHash, Sequence, Witness};
 
 	use alloc::vec;
 
 	#[test]
 	fn sort_output_by_value() {
 		let txout1 = TxOut {
-			value:  Amount::from_sat(100),
-			script_pubkey: Builder::new().push_int(0).into_script()
+			value: Amount::from_sat(100),
+			script_pubkey: Builder::new().push_int(0).into_script(),
 		};
 		let txout1_ = txout1.clone();
 
 		let txout2 = TxOut {
 			value: Amount::from_sat(99),
-			script_pubkey: Builder::new().push_int(0).into_script()
+			script_pubkey: Builder::new().push_int(0).into_script(),
 		};
 		let txout2_ = txout2.clone();
 
 		let mut outputs = vec![(txout1, "ignore"), (txout2, "ignore")];
-		sort_outputs(&mut outputs, |_, _| { unreachable!(); });
+		sort_outputs(&mut outputs, |_, _| {
+			unreachable!();
+		});
 
-		assert_eq!(
-			&outputs,
-			&vec![(txout2_, "ignore"), (txout1_, "ignore")]
-			);
+		assert_eq!(&outputs, &vec![(txout2_, "ignore"), (txout1_, "ignore")]);
 	}
 
 	#[test]
 	fn sort_output_by_script_pubkey() {
 		let txout1 = TxOut {
-			value:  Amount::from_sat(100),
+			value: Amount::from_sat(100),
 			script_pubkey: Builder::new().push_int(3).into_script(),
 		};
 		let txout1_ = txout1.clone();
 
 		let txout2 = TxOut {
 			value: Amount::from_sat(100),
-			script_pubkey: Builder::new().push_int(1).push_int(2).into_script()
+			script_pubkey: Builder::new().push_int(1).push_int(2).into_script(),
 		};
 		let txout2_ = txout2.clone();
 
 		let mut outputs = vec![(txout1, "ignore"), (txout2, "ignore")];
-		sort_outputs(&mut outputs, |_, _| { unreachable!(); });
+		sort_outputs(&mut outputs, |_, _| {
+			unreachable!();
+		});
 
-		assert_eq!(
-			&outputs,
-			&vec![(txout2_, "ignore"), (txout1_, "ignore")]
-			);
+		assert_eq!(&outputs, &vec![(txout2_, "ignore"), (txout1_, "ignore")]);
 	}
 
 	#[test]
@@ -145,29 +151,28 @@ mod tests {
 		let txout2_ = txout2.clone();
 
 		let mut outputs = vec![(txout1, "ignore"), (txout2, "ignore")];
-		sort_outputs(&mut outputs, |_, _| { unreachable!(); });
+		sort_outputs(&mut outputs, |_, _| {
+			unreachable!();
+		});
 
 		assert_eq!(&outputs, &vec![(txout1_, "ignore"), (txout2_, "ignore")]);
 	}
 
 	#[test]
 	fn sort_output_tie_breaker_test() {
 		let txout1 = TxOut {
-			value:  Amount::from_sat(100),
-			script_pubkey: Builder::new().push_int(1).push_int(2).into_script()
+			value: Amount::from_sat(100),
+			script_pubkey: Builder::new().push_int(1).push_int(2).into_script(),
 		};
 		let txout1_ = txout1.clone();
 
 		let txout2 = txout1.clone();
 		let txout2_ = txout1.clone();
 
 		let mut outputs = vec![(txout1, 420), (txout2, 69)];
-		sort_outputs(&mut outputs, |a, b| { a.cmp(b) });
+		sort_outputs(&mut outputs, |a, b| a.cmp(b));
 
-		assert_eq!(
-			&outputs,
-			&vec![(txout2_, 69), (txout1_, 420)]
-		);
+		assert_eq!(&outputs, &vec![(txout2_, 69), (txout1_, 420)]);
 	}
 
 	fn script_from_hex(hex_str: &str) -> ScriptBuf {
@@ -215,18 +220,35 @@ mod tests {
 	#[test]
 	fn test_tx_value_overrun() {
 		// If we have a bogus input amount or outputs valued more than inputs, we should fail
-		let mut tx = Transaction { version: Version::TWO, lock_time: LockTime::ZERO, input: Vec::new(), output: vec![TxOut {
-			script_pubkey: ScriptBuf::new(), value: Amount::from_sat(1000)
-		}] };
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(21_000_000_0000_0001), 0, 253, ScriptBuf::new()).is_err());
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(400), 0, 253, ScriptBuf::new()).is_err());
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(4000), 0, 253, ScriptBuf::new()).is_ok());
+		let mut tx = Transaction {
+			version: Version::TWO,
+			lock_time: LockTime::ZERO,
+			input: Vec::new(),
+			output: vec![TxOut { script_pubkey: ScriptBuf::new(), value: Amount::from_sat(1000) }],
+		};
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(21_000_000_0000_0001),
+			0,
+			253,
+			ScriptBuf::new()
+		)
+		.is_err());
+		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(400), 0, 253, ScriptBuf::new())
+			.is_err());
+		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(4000), 0, 253, ScriptBuf::new())
+			.is_ok());
 	}
 
 	#[test]
 	fn test_tx_change_edge() {
 		// Check that we never add dust outputs
-		let mut tx = Transaction { version: Version::TWO, lock_time: LockTime::ZERO, input: Vec::new(), output: Vec::new() };
+		let mut tx = Transaction {
+			version: Version::TWO,
+			lock_time: LockTime::ZERO,
+			input: Vec::new(),
+			output: Vec::new(),
+		};
 		let orig_wtxid = tx.compute_wtxid();
 		let output_spk = ScriptBuf::new_p2pkh(&PubkeyHash::hash(&[0; 0]));
 		assert_eq!(output_spk.minimal_non_dust().to_sat(), 546);
@@ -235,25 +257,48 @@ mod tests {
 		// weight = 3 * base size + total size = 3 * (4 + 1 + 0 + 1 + 0 + 4) + (4 + 1 + 1 + 1 + 0 + 1 + 0 + 4) = 3 * 10 + 12 = 42
 		assert_eq!(tx.weight().to_wu(), 42);
 		// 10 sats isn't enough to pay fee on a dummy transaction...
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(10), 0, 250, output_spk.clone()).is_err());
+		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(10), 0, 250, output_spk.clone())
+			.is_err());
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // Failure doesn't change the transaction
-		// but 11 (= ceil(42 * 250 / 1000)) is, just not enough to add a change output...
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(11), 0, 250, output_spk.clone()).is_ok());
+											// but 11 (= ceil(42 * 250 / 1000)) is, just not enough to add a change output...
+		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(11), 0, 250, output_spk.clone())
+			.is_ok());
 		assert_eq!(tx.output.len(), 0);
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // If we don't add an output, we don't change the transaction
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(549), 0, 250, output_spk.clone()).is_ok());
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(549),
+			0,
+			250,
+			output_spk.clone()
+		)
+		.is_ok());
 		assert_eq!(tx.output.len(), 0);
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // If we don't add an output, we don't change the transaction
-		// 590 is also not enough
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(590), 0, 250, output_spk.clone()).is_ok());
+											// 590 is also not enough
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(590),
+			0,
+			250,
+			output_spk.clone()
+		)
+		.is_ok());
 		assert_eq!(tx.output.len(), 0);
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // If we don't add an output, we don't change the transaction
-		// at 591 we can afford the change output at the dust limit (546)
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(591), 0, 250, output_spk.clone()).is_ok());
+											// at 591 we can afford the change output at the dust limit (546)
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(591),
+			0,
+			250,
+			output_spk.clone()
+		)
+		.is_ok());
 		assert_eq!(tx.output.len(), 1);
 		assert_eq!(tx.output[0].value.to_sat(), 546);
 		assert_eq!(tx.output[0].script_pubkey, output_spk);
-		assert_eq!(tx.weight().to_wu() / 4, 590-546); // New weight is exactly the fee we wanted.
+		assert_eq!(tx.weight().to_wu() / 4, 590 - 546); // New weight is exactly the fee we wanted.
 
 		tx.output.pop();
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // The only change is the addition of one output.
@@ -262,28 +307,65 @@ mod tests {
 	#[test]
 	fn test_tx_extra_outputs() {
 		// Check that we correctly handle existing outputs
-		let mut tx = Transaction { version: Version::TWO, lock_time: LockTime::ZERO, input: vec![TxIn {
-			previous_output: OutPoint::new(Txid::all_zeros(), 0), script_sig: ScriptBuf::new(), witness: Witness::new(), sequence: Sequence::ZERO,
-		}], output: vec![TxOut {
-			script_pubkey: Builder::new().push_int(1).into_script(), value: Amount::from_sat(1000)
-		}] };
+		let mut tx = Transaction {
+			version: Version::TWO,
+			lock_time: LockTime::ZERO,
+			input: vec![TxIn {
+				previous_output: OutPoint::new(Txid::all_zeros(), 0),
+				script_sig: ScriptBuf::new(),
+				witness: Witness::new(),
+				sequence: Sequence::ZERO,
+			}],
+			output: vec![TxOut {
+				script_pubkey: Builder::new().push_int(1).into_script(),
+				value: Amount::from_sat(1000),
+			}],
+		};
 		let orig_wtxid = tx.compute_wtxid();
 		let orig_weight = tx.weight().to_wu();
 		assert_eq!(orig_weight / 4, 61);
 
 		assert_eq!(Builder::new().push_int(2).into_script().minimal_non_dust().to_sat(), 474);
 
 		// Input value of the output value + fee - 1 should fail:
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(1000 + 61 + 100 - 1), 400, 250, Builder::new().push_int(2).into_script()).is_err());
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(1000 + 61 + 100 - 1),
+			400,
+			250,
+			Builder::new().push_int(2).into_script()
+		)
+		.is_err());
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // Failure doesn't change the transaction
-		// but one more input sat should succeed, without changing the transaction
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(1000 + 61 + 100), 400, 250, Builder::new().push_int(2).into_script()).is_ok());
+											// but one more input sat should succeed, without changing the transaction
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(1000 + 61 + 100),
+			400,
+			250,
+			Builder::new().push_int(2).into_script()
+		)
+		.is_ok());
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // If we don't add an output, we don't change the transaction
-		// In order to get a change output, we need to add 474 plus the output's weight / 4 (10)...
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(1000 + 61 + 100 + 474 + 9), 400, 250, Builder::new().push_int(2).into_script()).is_ok());
+											// In order to get a change output, we need to add 474 plus the output's weight / 4 (10)...
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(1000 + 61 + 100 + 474 + 9),
+			400,
+			250,
+			Builder::new().push_int(2).into_script()
+		)
+		.is_ok());
 		assert_eq!(tx.compute_wtxid(), orig_wtxid); // If we don't add an output, we don't change the transaction
 
-		assert!(maybe_add_change_output(&mut tx, Amount::from_sat(1000 + 61 + 100 + 474 + 10), 400, 250, Builder::new().push_int(2).into_script()).is_ok());
+		assert!(maybe_add_change_output(
+			&mut tx,
+			Amount::from_sat(1000 + 61 + 100 + 474 + 10),
+			400,
+			250,
+			Builder::new().push_int(2).into_script()
+		)
+		.is_ok());
 		assert_eq!(tx.output.len(), 2);
 		assert_eq!(tx.output[1].value.to_sat(), 474);
 		assert_eq!(tx.output[1].script_pubkey, Builder::new().push_int(2).into_script());