Merge rust-bitcoin/rust-bitcoin#3058: Improve `define_extension_trait`

386ad93253 Manually format function parameters (Tobin C. Harding)
871f4398b9 Add optional comma to function parameter list (Tobin C. Harding)

Pull request description:

  During #2955 I was lazy and did not think through why the macro didn't handle function parameters on individual lines, I just manually re-formatted all function calls onto a single LOC. This was a bit slack of me.

  - Patch 1: Fix the macro.
  - Patch 2: Revert the manual formatting.

ACKs for top commit:
  jamillambert:
    ACK 386ad93253
  Kixunil:
    ACK 386ad93253
  apoelstra:
    ACK 386ad93253

Tree-SHA512: 577154668a4cd0bad225a5b306193a5cd3d38d275dd5df22b4a29737e0d2c910c695da33c0ed77265f6c5d876c162316e444f8eca80f9c30788d110d989493e3

bitcoin/src/address/script_pubkey.rs

@@ -48,7 +48,11 @@ define_extension_trait! {
 
         /// Computes P2TR output with a given internal key and a single script spending path equal to
         /// the current script, assuming that the script is a Tapscript.
-        fn to_p2tr<C: Verification>(&self, secp: &Secp256k1<C>, internal_key: UntweakedPublicKey) -> ScriptBuf {
+        fn to_p2tr<C: Verification>(
+            &self,
+            secp: &Secp256k1<C>,
+            internal_key: UntweakedPublicKey,
+        ) -> ScriptBuf {
             let leaf_hash = self.tapscript_leaf_hash();
             let merkle_root = TapNodeHash::from(leaf_hash);
             ScriptBuf::new_p2tr(secp, internal_key, Some(merkle_root))
@@ -150,7 +154,11 @@ define_extension_trait! {
 
         /// Generates P2TR for script spending path using an internal public key and some optional
         /// script tree Merkle root.
-        fn new_p2tr<C: Verification>(secp: &Secp256k1<C>, internal_key: UntweakedPublicKey, merkle_root: Option<TapNodeHash>) -> Self {
+        fn new_p2tr<C: Verification>(
+            secp: &Secp256k1<C>,
+            internal_key: UntweakedPublicKey,
+            merkle_root: Option<TapNodeHash>,
+        ) -> Self {
             let (output_key, _) = internal_key.tap_tweak(secp, merkle_root);
             // output key is 32 bytes long, so it's safe to use `new_witness_program_unchecked` (Segwitv1)
             new_witness_program_unchecked(WitnessVersion::V1, output_key.serialize())

bitcoin/src/internal_macros.rs

@@ -218,7 +218,7 @@ macro_rules! define_extension_trait {
     ($(#[$($trait_attrs:tt)*])* $trait_vis:vis trait $trait_name:ident impl for $ty:ident {
         $(
             $(#[$($fn_attrs:tt)*])*
-            fn $fn:ident($slf:ident $(, $param_name:ident: $param_type:ty)*) $( -> $ret:ty )? $body:block
+            fn $fn:ident($slf:ident $(, $param_name:ident: $param_type:ty)* $(,)?) $( -> $ret:ty )? $body:block
         )*
     }) => {
         $(#[$($trait_attrs)*])* $trait_vis trait $trait_name {
@@ -238,7 +238,7 @@ macro_rules! define_extension_trait {
     ($(#[$($trait_attrs:tt)*])* $trait_vis:vis trait $trait_name:ident impl for $ty:ident {
         $(
             $(#[$($fn_attrs:tt)*])*
-            fn $fn:ident(&$slf:ident $(, $param_name:ident: $param_type:ty)*) $( -> $ret:ty )? $body:block
+            fn $fn:ident(&$slf:ident $(, $param_name:ident: $param_type:ty)* $(,)?) $( -> $ret:ty )? $body:block
         )*
     }) => {
         $(#[$($trait_attrs)*])* $trait_vis trait $trait_name {
@@ -258,7 +258,7 @@ macro_rules! define_extension_trait {
     ($(#[$($trait_attrs:tt)*])* $trait_vis:vis trait $trait_name:ident impl for $ty:ident {
         $(
             $(#[$($fn_attrs:tt)*])*
-            fn $fn:ident$(<$($gen:ident: $gent:ident),*>)?(&$slf:ident $(, $param_name:ident: $param_type:ty)*) $( -> $ret:ty )? $body:block
+            fn $fn:ident$(<$($gen:ident: $gent:ident),*>)?(&$slf:ident $(, $param_name:ident: $param_type:ty)* $(,)?) $( -> $ret:ty )? $body:block
         )*
     }) => {
         $(#[$($trait_attrs)*])* $trait_vis trait $trait_name {
@@ -278,7 +278,7 @@ macro_rules! define_extension_trait {
     ($(#[$($trait_attrs:tt)*])* $trait_vis:vis trait $trait_name:ident impl for $ty:ident {
         $(
             $(#[$($fn_attrs:tt)*])*
-            fn $fn:ident$(<$($gen:ident: $gent:ident),*>)?($($param_name:ident: $param_type:ty),*) $( -> $ret:ty )? $body:block
+            fn $fn:ident$(<$($gen:ident: $gent:ident),*>)?($($param_name:ident: $param_type:ty),* $(,)?) $( -> $ret:ty )? $body:block
         )*
     }) => {
         $(#[$($trait_attrs)*])* $trait_vis trait $trait_name {
@@ -298,7 +298,7 @@ macro_rules! define_extension_trait {
     ($(#[$($trait_attrs:tt)*])* $trait_vis:vis trait $trait_name:ident impl for $ty:ident {
         $(
             $(#[$($fn_attrs:tt)*])*
-            fn $fn:ident<T: AsRef<PushBytes>>($($param_name:ident: $param_type:ty),*) $( -> $ret:ty )? $body:block
+            fn $fn:ident<T: AsRef<PushBytes>>($($param_name:ident: $param_type:ty),* $(,)?) $( -> $ret:ty )? $body:block
         )*
     }) => {
         $(#[$($trait_attrs)*])* $trait_vis trait $trait_name {