Move the transaction hash types over to primitives

Move the `Txid` and `Wtxid` hash wrapper types over to `primitives`.
This introduces to `primitves` an unconditional dependency on
`hashes`.

Cargo-minimal.lock

@@ -113,6 +113,7 @@ dependencies = [
  "bitcoin-internals",
  "bitcoin-io",
  "bitcoin-units",
+ "bitcoin_hashes",
  "mutagen",
  "ordered",
  "serde",

Cargo-recent.lock

@@ -112,6 +112,7 @@ dependencies = [
  "bitcoin-internals",
  "bitcoin-io",
  "bitcoin-units",
+ "bitcoin_hashes",
  "mutagen",
  "ordered",
  "serde",

bitcoin/src/blockdata/transaction.rs

@@ -35,31 +35,9 @@ use crate::{Amount, FeeRate, SignedAmount, VarInt};
 #[doc(inline)]
 pub use primitives::transaction::*;
 
-hashes::hash_newtype! {
-    /// A bitcoin transaction hash/transaction ID.
-    ///
-    /// For compatibility with the existing Bitcoin infrastructure and historical and current
-    /// versions of the Bitcoin Core software itself, this and other [`sha256d::Hash`] types, are
-    /// serialized in reverse byte order when converted to a hex string via [`std::fmt::Display`]
-    /// trait operations.
-    ///
-    /// See [`hashes::Hash::DISPLAY_BACKWARD`] for more details.
-    pub struct Txid(sha256d::Hash);
-
-    /// A bitcoin witness transaction ID.
-    pub struct Wtxid(sha256d::Hash);
-}
 impl_hashencode!(Txid);
 impl_hashencode!(Wtxid);
 
-impl Txid {
-    /// The `Txid` used in a coinbase prevout.
-    ///
-    /// This is used as the "txid" of the dummy input of a coinbase transaction. This is not a real
-    /// TXID and should not be used in any other contexts. See [`OutPoint::COINBASE_PREVOUT`].
-    pub const COINBASE_PREVOUT: Self = Self::from_byte_array([0; 32]);
-}
-
 crate::internal_macros::define_extension_trait! {
     /// Extension functionality for the [`Txid`] type.
     pub trait TxidExt impl for Txid {
@@ -69,15 +47,6 @@ crate::internal_macros::define_extension_trait! {
     }
 }
 
-impl Wtxid {
-    /// The `Wtxid` of a coinbase transaction.
-    ///
-    /// This is used as the wTXID for the coinbase transaction when constructing blocks (in the
-    /// witness commitment tree) since the coinbase transaction contains a commitment to all
-    /// transactions' wTXIDs but naturally cannot commit to its own.
-    pub const COINBASE: Self = Self::from_byte_array([0; 32]);
-}
-
 crate::internal_macros::define_extension_trait! {
     /// Extension functionality for the [`Wtxid`] type.
     pub trait WtxidExt impl for Wtxid {

primitives/Cargo.toml

@@ -16,11 +16,12 @@ exclude = ["tests", "contrib"]
 
 [features]
 default = ["std"]
-std = ["alloc", "internals/std", "io/std", "units/std"]
+std = ["alloc", "hashes/std", "internals/std", "io/std", "units/std"]
-alloc = ["internals/alloc", "io/alloc", "units/alloc"]
+alloc = ["hashes/alloc", "internals/alloc", "io/alloc", "units/alloc"]
-serde = ["dep:serde", "internals/serde", "units/serde", "alloc"]
+serde = ["dep:serde", "hashes/serde", "internals/serde", "units/serde", "alloc"]
 
 [dependencies]
+hashes = { package = "bitcoin_hashes", version = "0.14.0", default-features = false, features = ["bitcoin-io"] }
 internals = { package = "bitcoin-internals", version = "0.3.0" }
 io = { package = "bitcoin-io", version = "0.1.1", default-features = false }
 units = { package = "bitcoin-units", version = "0.1.0", default-features = false }

primitives/src/lib.rs

@@ -42,7 +42,11 @@ pub use units::*;
 #[cfg(feature = "alloc")]
 pub use self::locktime::{absolute, relative};
 #[doc(inline)]
-pub use self::{pow::CompactTarget, sequence::Sequence};
+pub use self::{
+    pow::CompactTarget,
+    sequence::Sequence,
+    transaction::{Txid, Wtxid},
+};
 
 #[rustfmt::skip]
 #[allow(unused_imports)]

primitives/src/transaction.rs

@@ -12,6 +12,40 @@
 
 use core::fmt;
 
+use hashes::sha256d;
+
+hashes::hash_newtype! {
+    /// A bitcoin transaction hash/transaction ID.
+    ///
+    /// For compatibility with the existing Bitcoin infrastructure and historical and current
+    /// versions of the Bitcoin Core software itself, this and other [`sha256d::Hash`] types, are
+    /// serialized in reverse byte order when converted to a hex string via [`std::fmt::Display`]
+    /// trait operations.
+    ///
+    /// See [`hashes::Hash::DISPLAY_BACKWARD`] for more details.
+    pub struct Txid(sha256d::Hash);
+
+    /// A bitcoin witness transaction ID.
+    pub struct Wtxid(sha256d::Hash);
+}
+
+impl Txid {
+    /// The `Txid` used in a coinbase prevout.
+    ///
+    /// This is used as the "txid" of the dummy input of a coinbase transaction. This is not a real
+    /// TXID and should not be used in any other contexts. See `OutPoint::COINBASE_PREVOUT`.
+    pub const COINBASE_PREVOUT: Self = Self::from_byte_array([0; 32]);
+}
+
+impl Wtxid {
+    /// The `Wtxid` of a coinbase transaction.
+    ///
+    /// This is used as the wTXID for the coinbase transaction when constructing blocks (in the
+    /// witness commitment tree) since the coinbase transaction contains a commitment to all
+    /// transactions' wTXIDs but naturally cannot commit to its own.
+    pub const COINBASE: Self = Self::from_byte_array([0; 32]);
+}
+
 /// The transaction version.
 ///
 /// Currently, as specified by [BIP-68], only version 1 and 2 are considered standard.