Merge rust-bitcoin/rust-bitcoin#3487: Move `TxIn` and `TxOut` to `primitives`

003dc9cf4d Move TxOut to primitives (Tobin C. Harding)
4d37d7efc6 Move TxIn to primitives (Tobin C. Harding)
ce0d517383 Use explicit re-export of transaction types (Tobin C. Harding)
4c5dba82f4 Introduce TxInExt trait (Tobin C. Harding)
b7e6c698f8 Split the TxIn impl block in two (Tobin C. Harding)
265589d93d Make TxIn::BASE_WEIGHT a file level const (Tobin C. Harding)

Pull request description:

  Turn the crank; move `TxIn` and `TxOut` to `primitives`.

ACKs for top commit:
  apoelstra:
    ACK 003dc9cf4d80c2a6d614de1e3a1c7c4b1d5372e0; successfully ran local tests

Tree-SHA512: fa9ffb7677999f0e07231d4603db5c005d4dc1c1b9d1faa8df9e90bd8a8088f853c3e0cd2997ca724f6a4e13941afedf5877ba95ac70f31e7b3438b34c205034

bitcoin/src/blockdata/transaction.rs

@@ -32,7 +32,7 @@ use crate::{Amount, FeeRate, SignedAmount};
 
 #[rustfmt::skip]            // Keep public re-exports separate.
 #[doc(inline)]
-pub use primitives::transaction::*;
+pub use primitives::transaction::{OutPoint, ParseOutPointError, Txid, Wtxid, Version, TxIn, TxOut};
 
 impl_hashencode!(Txid);
 impl_hashencode!(Wtxid);
@@ -82,51 +82,16 @@ crate::internal_macros::define_extension_trait! {
     }
 }
 
-/// Bitcoin transaction input.
+/// Returns the input base weight.
 ///
-/// It contains the location of the previous transaction's output,
+/// Base weight excludes the witness and script.
-/// that it spends and set of scripts that satisfy its spending
+// We need to use this const here but do not want to make it public in `primitives::TxIn`.
-/// conditions.
+const TX_IN_BASE_WEIGHT: Weight =
-///
-/// ### Bitcoin Core References
-///
-/// * [CTxIn definition](https://github.com/bitcoin/bitcoin/blob/345457b542b6a980ccfbc868af0970a6f91d1b82/src/primitives/transaction.h#L65)
-#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub struct TxIn {
-    /// The reference to the previous output that is being used as an input.
-    pub previous_output: OutPoint,
-    /// The script which pushes values on the stack which will cause
-    /// the referenced output's script to be accepted.
-    pub script_sig: ScriptBuf,
-    /// The sequence number, which suggests to miners which of two
-    /// conflicting transactions should be preferred, or 0xFFFFFFFF
-    /// to ignore this feature. This is generally never used since
-    /// the miner behavior cannot be enforced.
-    pub sequence: Sequence,
-    /// Witness data: an array of byte-arrays.
-    /// Note that this field is *not* (de)serialized with the rest of the TxIn in
-    /// Encodable/Decodable, as it is (de)serialized at the end of the full
-    /// Transaction. It *is* (de)serialized with the rest of the TxIn in other
-    /// (de)serialization routines.
-    pub witness: Witness,
-}
-
-impl TxIn {
-    /// An empty transaction input with the previous output as for a coinbase transaction.
-    pub const EMPTY_COINBASE: TxIn = TxIn {
-        previous_output: OutPoint::COINBASE_PREVOUT,
-        script_sig: ScriptBuf::new(),
-        sequence: Sequence::MAX,
-        witness: Witness::new(),
-    };
-
-    /// Returns the input base weight.
-    ///
-    /// Base weight excludes the witness and script.
-    const BASE_WEIGHT: Weight =
     Weight::from_vb_unwrap(OutPoint::SIZE as u64 + Sequence::SIZE as u64);
 
+crate::internal_macros::define_extension_trait! {
+    /// Extension functionality for the [`TxIn`] type.
+    pub trait TxInExt impl for TxIn {
         /// Returns true if this input enables the [`absolute::LockTime`] (aka `nLockTime`) of its
         /// [`Transaction`].
         ///
@@ -136,7 +101,7 @@ impl TxIn {
         ///  this input then the script execution will fail [BIP-0065].
         ///
         /// [BIP-65](https://github.com/bitcoin/bips/blob/master/bip-0065.mediawiki)
-    pub fn enables_lock_time(&self) -> bool { self.sequence != Sequence::MAX }
+        fn enables_lock_time(&self) -> bool { self.sequence != Sequence::MAX }
 
         /// The weight of the TxIn when it's included in a legacy transaction (i.e., a transaction
         /// having only legacy inputs).
@@ -147,7 +112,7 @@ impl TxIn {
         /// Keep in mind that when adding a TxIn to a transaction, the total weight of the transaction
         /// might increase more than `TxIn::legacy_weight`. This happens when the new input added causes
         /// the input length `VarInt` to increase its encoding length.
-    pub fn legacy_weight(&self) -> Weight {
+        fn legacy_weight(&self) -> Weight {
             Weight::from_non_witness_data_size(self.base_size().to_u64())
         }
 
@@ -162,7 +127,7 @@ impl TxIn {
         /// - the new input added causes the input length `VarInt` to increase its encoding length
         /// - the new input is the first segwit input added - this will add an additional 2WU to the
         ///   transaction weight to take into account the segwit marker
-    pub fn segwit_weight(&self) -> Weight {
+        fn segwit_weight(&self) -> Weight {
             Weight::from_non_witness_data_size(self.base_size().to_u64())
                 + Weight::from_witness_data_size(self.witness.size().to_u64())
         }
@@ -170,7 +135,7 @@ impl TxIn {
         /// Returns the base size of this input.
         ///
         /// Base size excludes the witness data (see [`Self::total_size`]).
-    pub fn base_size(&self) -> usize {
+        fn base_size(&self) -> usize {
             let mut size = OutPoint::SIZE;
 
             size += compact_size::encoded_size(self.script_sig.len());
@@ -182,33 +147,8 @@ impl TxIn {
         /// Returns the total number of bytes that this input contributes to a transaction.
         ///
         /// Total size includes the witness data (for base size see [`Self::base_size`]).
-    pub fn total_size(&self) -> usize { self.base_size() + self.witness.size() }
+        fn total_size(&self) -> usize { self.base_size() + self.witness.size() }
-}
+    }
-
-/// Bitcoin transaction output.
-///
-/// Defines new coins to be created as a result of the transaction,
-/// along with spending conditions ("script", aka "output script"),
-/// which an input spending it must satisfy.
-///
-/// An output that is not yet spent by an input is called Unspent Transaction Output ("UTXO").
-///
-/// ### Bitcoin Core References
-///
-/// * [CTxOut definition](https://github.com/bitcoin/bitcoin/blob/345457b542b6a980ccfbc868af0970a6f91d1b82/src/primitives/transaction.h#L148)
-#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub struct TxOut {
-    /// The value of the output, in satoshis.
-    pub value: Amount,
-    /// The script which must be satisfied for the output to be spent.
-    pub script_pubkey: ScriptBuf,
-}
-
-impl TxOut {
-    /// This is used as a "null txout" in consensus signing code.
-    pub const NULL: Self =
-        TxOut { value: Amount::from_sat(0xffffffffffffffff), script_pubkey: ScriptBuf::new() };
 }
 
 crate::internal_macros::define_extension_trait! {
@@ -265,13 +205,6 @@ crate::internal_macros::define_extension_trait! {
     }
 }
 
-#[cfg(feature = "arbitrary")]
-impl<'a> Arbitrary<'a> for TxOut {
-    fn arbitrary(u: &mut Unstructured<'a>) -> arbitrary::Result<Self> {
-        Ok(TxOut { value: Amount::arbitrary(u)?, script_pubkey: ScriptBuf::arbitrary(u)? })
-    }
-}
-
 /// Returns the total number of bytes that this script pubkey would contribute to a transaction.
 fn size_from_script_pubkey(script_pubkey: &Script) -> usize {
     let len = script_pubkey.len();
@@ -955,7 +888,7 @@ pub fn effective_value(
     satisfaction_weight: Weight,
     value: Amount,
 ) -> Option<SignedAmount> {
-    let weight = satisfaction_weight.checked_add(TxIn::BASE_WEIGHT)?;
+    let weight = satisfaction_weight.checked_add(TX_IN_BASE_WEIGHT)?;
     let signed_input_fee = fee_rate.checked_mul_by_weight(weight)?.to_signed().ok()?;
     value.to_signed().ok()?.checked_sub(signed_input_fee)
 }
@@ -1304,18 +1237,6 @@ impl InputWeightPrediction {
     }
 }
 
-#[cfg(feature = "arbitrary")]
-impl<'a> Arbitrary<'a> for TxIn {
-    fn arbitrary(u: &mut Unstructured<'a>) -> arbitrary::Result<Self> {
-        Ok(TxIn {
-            previous_output: OutPoint::arbitrary(u)?,
-            script_sig: ScriptBuf::arbitrary(u)?,
-            sequence: Sequence::arbitrary(u)?,
-            witness: Witness::arbitrary(u)?,
-        })
-    }
-}
-
 #[cfg(feature = "arbitrary")]
 impl<'a> Arbitrary<'a> for Transaction {
     fn arbitrary(u: &mut Unstructured<'a>) -> arbitrary::Result<Self> {
@@ -1335,6 +1256,7 @@ mod sealed {
     impl Sealed for super::Txid {}
     impl Sealed for super::Wtxid {}
     impl Sealed for super::OutPoint {}
+    impl Sealed for super::TxIn {}
     impl Sealed for super::TxOut {}
     impl Sealed for super::Version {}
 }

primitives/src/lib.rs

@@ -59,6 +59,7 @@ pub use self::{
 pub use self::{
     locktime::{absolute, relative},
     witness::Witness,
+    transaction::{TxIn, TxOut},
 };
 
 #[rustfmt::skip]

primitives/src/transaction.rs

@@ -18,7 +18,84 @@ use hashes::sha256d;
 #[cfg(feature = "alloc")]
 use internals::write_err;
 #[cfg(feature = "alloc")]
-use units::parse;
+use units::{parse, Amount};
+
+#[cfg(feature = "alloc")]
+use crate::script::ScriptBuf;
+#[cfg(feature = "alloc")]
+use crate::sequence::Sequence;
+#[cfg(feature = "alloc")]
+use crate::witness::Witness;
+
+/// Bitcoin transaction input.
+///
+/// It contains the location of the previous transaction's output,
+/// that it spends and set of scripts that satisfy its spending
+/// conditions.
+///
+/// ### Bitcoin Core References
+///
+/// * [CTxIn definition](https://github.com/bitcoin/bitcoin/blob/345457b542b6a980ccfbc868af0970a6f91d1b82/src/primitives/transaction.h#L65)
+#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg(feature = "alloc")]
+pub struct TxIn {
+    /// The reference to the previous output that is being used as an input.
+    pub previous_output: OutPoint,
+    /// The script which pushes values on the stack which will cause
+    /// the referenced output's script to be accepted.
+    pub script_sig: ScriptBuf,
+    /// The sequence number, which suggests to miners which of two
+    /// conflicting transactions should be preferred, or 0xFFFFFFFF
+    /// to ignore this feature. This is generally never used since
+    /// the miner behavior cannot be enforced.
+    pub sequence: Sequence,
+    /// Witness data: an array of byte-arrays.
+    /// Note that this field is *not* (de)serialized with the rest of the TxIn in
+    /// Encodable/Decodable, as it is (de)serialized at the end of the full
+    /// Transaction. It *is* (de)serialized with the rest of the TxIn in other
+    /// (de)serialization routines.
+    pub witness: Witness,
+}
+
+#[cfg(feature = "alloc")]
+impl TxIn {
+    /// An empty transaction input with the previous output as for a coinbase transaction.
+    pub const EMPTY_COINBASE: TxIn = TxIn {
+        previous_output: OutPoint::COINBASE_PREVOUT,
+        script_sig: ScriptBuf::new(),
+        sequence: Sequence::MAX,
+        witness: Witness::new(),
+    };
+}
+
+/// Bitcoin transaction output.
+///
+/// Defines new coins to be created as a result of the transaction,
+/// along with spending conditions ("script", aka "output script"),
+/// which an input spending it must satisfy.
+///
+/// An output that is not yet spent by an input is called Unspent Transaction Output ("UTXO").
+///
+/// ### Bitcoin Core References
+///
+/// * [CTxOut definition](https://github.com/bitcoin/bitcoin/blob/345457b542b6a980ccfbc868af0970a6f91d1b82/src/primitives/transaction.h#L148)
+#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg(feature = "alloc")]
+pub struct TxOut {
+    /// The value of the output, in satoshis.
+    pub value: Amount,
+    /// The script which must be satisfied for the output to be spent.
+    pub script_pubkey: ScriptBuf,
+}
+
+#[cfg(feature = "alloc")]
+impl TxOut {
+    /// This is used as a "null txout" in consensus signing code.
+    pub const NULL: Self =
+        TxOut { value: Amount::from_sat(0xffffffffffffffff), script_pubkey: ScriptBuf::new() };
+}
 
 /// A reference to a transaction output.
 ///
@@ -199,6 +276,27 @@ impl fmt::Display for Version {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { fmt::Display::fmt(&self.0, f) }
 }
 
+#[cfg(feature = "arbitrary")]
+#[cfg(feature = "alloc")]
+impl<'a> Arbitrary<'a> for TxIn {
+    fn arbitrary(u: &mut Unstructured<'a>) -> arbitrary::Result<Self> {
+        Ok(TxIn {
+            previous_output: OutPoint::arbitrary(u)?,
+            script_sig: ScriptBuf::arbitrary(u)?,
+            sequence: Sequence::arbitrary(u)?,
+            witness: Witness::arbitrary(u)?,
+        })
+    }
+}
+
+#[cfg(feature = "arbitrary")]
+#[cfg(feature = "alloc")]
+impl<'a> Arbitrary<'a> for TxOut {
+    fn arbitrary(u: &mut Unstructured<'a>) -> arbitrary::Result<Self> {
+        Ok(TxOut { value: Amount::arbitrary(u)?, script_pubkey: ScriptBuf::arbitrary(u)? })
+    }
+}
+
 #[cfg(feature = "arbitrary")]
 impl<'a> Arbitrary<'a> for OutPoint {
     fn arbitrary(u: &mut Unstructured<'a>) -> arbitrary::Result<Self> {