fee and lock_height maintained in kernel features variants (#2859)

* fee and lock_height now maintained in kernel features enum variants

* sum fees via explicit enum variants

* cleanup semantics around with_fee and with_lock_height for tx builders

* document the kernel feature variants

* serialize kernel features correctly for api json

* cleanup

* commit

* bump to unstick azure

api/src/types.rs

@@ -17,6 +17,7 @@ use std::sync::Arc;
 use crate::chain;
 use crate::core::core::hash::Hashed;
 use crate::core::core::merkle_proof::MerkleProof;
+use crate::core::core::KernelFeatures;
 use crate::core::{core, ser};
 use crate::p2p;
 use crate::util;
@@ -488,10 +489,16 @@ pub struct TxKernelPrintable {
 
 impl TxKernelPrintable {
 	pub fn from_txkernel(k: &core::TxKernel) -> TxKernelPrintable {
+		let features = k.features.as_string();
+		let (fee, lock_height) = match k.features {
+			KernelFeatures::Plain { fee } => (fee, 0),
+			KernelFeatures::Coinbase => (0, 0),
+			KernelFeatures::HeightLocked { fee, lock_height } => (fee, lock_height),
+		};
 		TxKernelPrintable {
-			features: format!("{:?}", k.features),
-			fee: k.fee,
-			lock_height: k.lock_height,
+			features,
+			fee,
+			lock_height,
 			excess: util::to_hex(k.excess.0.to_vec()),
 			excess_sig: util::to_hex(k.excess_sig.to_raw_data().to_vec()),
 		}

core/src/core/block.rs

@@ -28,8 +28,10 @@ use crate::core::compact_block::{CompactBlock, CompactBlockBody};
 use crate::core::hash::{DefaultHashable, Hash, Hashed, ZERO_HASH};
 use crate::core::verifier_cache::VerifierCache;
 use crate::core::{
-	transaction, Commitment, Input, Output, Transaction, TransactionBody, TxKernel, Weighting,
+	transaction, Commitment, Input, KernelFeatures, Output, Transaction, TransactionBody, TxKernel,
+	Weighting,
 };
+
 use crate::global;
 use crate::keychain::{self, BlindingFactor};
 use crate::pow::{Difficulty, Proof, ProofOfWork};
@@ -643,10 +645,7 @@ impl Block {
 
 	/// Sum of all fees (inputs less outputs) in the block
 	pub fn total_fees(&self) -> u64 {
-		self.body
-			.kernels
-			.iter()
-			.fold(0, |acc, ref x| acc.saturating_add(x.fee))
+		self.body.fee()
 	}
 
 	/// Matches any output with a potential spending input, eliminating them
@@ -762,8 +761,10 @@ impl Block {
 		for k in &self.body.kernels {
 			// check we have no kernels with lock_heights greater than current height
 			// no tx can be included in a block earlier than its lock_height
-			if k.lock_height > self.header.height {
-				return Err(Error::KernelLockHeight(k.lock_height));
+			if let KernelFeatures::HeightLocked { lock_height, .. } = k.features {
+				if lock_height > self.header.height {
+					return Err(Error::KernelLockHeight(lock_height));
+				}
 			}
 		}
 		Ok(())

core/src/core/hash.rs

@@ -253,4 +253,5 @@ impl<D: DefaultHashable, E: DefaultHashable, F: DefaultHashable> DefaultHashable
 /// Implement Hashed trait for external types here
 impl DefaultHashable for crate::util::secp::pedersen::RangeProof {}
 impl DefaultHashable for Vec<u8> {}
+impl DefaultHashable for u8 {}
 impl DefaultHashable for u64 {}