refactor: proving cost in fee header (#12048)

l1-contracts/src/core/Rollup.sol

@@ -11,6 +11,7 @@ import {
   EnumerableSet
 } from "@aztec/core/interfaces/IStaking.sol";
 import {IValidatorSelection} from "@aztec/core/interfaces/IValidatorSelection.sol";
+import {FeeAssetValue} from "@aztec/core/libraries/RollupLibs/FeeMath.sol";
 
 // We allow the unused imports here as they make it much simpler to import the Rollup later
 // solhint-disable no-unused-import
@@ -39,7 +40,6 @@ import {
   EpochRewards,
   FeeAssetPerEthE9,
   EthValue,
-  FeeAssetValue,
   PriceLib
 } from "./RollupCore.sol";
 // solhint-enable no-unused-import

l1-contracts/src/core/RollupCore.sol

@@ -32,12 +32,7 @@ import {
   ValidateHeaderArgs,
   Header
 } from "@aztec/core/libraries/RollupLibs/ExtRollupLib.sol";
-import {
-  EthValue,
-  FeeAssetValue,
-  FeeAssetPerEthE9,
-  PriceLib
-} from "@aztec/core/libraries/RollupLibs/FeeMath.sol";
+import {EthValue, FeeAssetPerEthE9, PriceLib} from "@aztec/core/libraries/RollupLibs/FeeMath.sol";
 import {IntRollupLib} from "@aztec/core/libraries/RollupLibs/IntRollupLib.sol";
 import {ProposeArgs, ProposeLib} from "@aztec/core/libraries/RollupLibs/ProposeLib.sol";
 import {StakingLib} from "@aztec/core/libraries/staking/StakingLib.sol";
@@ -175,7 +170,13 @@ contract RollupCore is
 
     // Genesis block
     rollupStore.blocks[0] = BlockLog({
-      feeHeader: FeeHeader({excessMana: 0, feeAssetPriceNumerator: 0, manaUsed: 0, congestionCost: 0}),
+      feeHeader: FeeHeader({
+        excessMana: 0,
+        feeAssetPriceNumerator: 0,
+        manaUsed: 0,
+        congestionCost: 0,
+        provingCost: 0
+      }),
       archive: _genesisArchiveRoot,
       blockHash: _genesisBlockHash,
       slotNumber: Slot.wrap(0)
@@ -424,18 +425,7 @@ contract RollupCore is
           interim.totalBurn += interim.burn;
 
           // Compute the proving fee in the fee asset
-          {
-            // @todo likely better for us to store this if we can pack it better
-            interim.feeAssetPrice = IntRollupLib.getFeeAssetPerEth(
-              rollupStore.blocks[_args.start + i - 1].feeHeader.feeAssetPriceNumerator
-            );
-          }
-          interim.proverFee = Math.min(
-            feeHeader.manaUsed
-              * FeeAssetValue.unwrap(rollupStore.provingCostPerMana.toFeeAsset(interim.feeAssetPrice)),
-            interim.fee
-          );
-
+          interim.proverFee = Math.min(feeHeader.manaUsed * feeHeader.provingCost, interim.fee);
           interim.fee -= interim.proverFee;
 
           er.rewards += interim.proverFee;
@@ -498,6 +488,11 @@ contract RollupCore is
     // Decode and validate header
     Header memory header = ExtRollupLib.decodeHeader(_args.header);
 
+    // @todo As part of a refactor of the core for propose and submit, we should
+    //       be able to set it up such that we don't need compute the fee components
+    //       unless needed.
+    //       Would be part of joining the header validation.
+
     setupEpoch();
     ManaBaseFeeComponents memory components =
       getManaBaseFeeComponentsAt(Timestamp.wrap(block.timestamp), true);
@@ -515,7 +510,9 @@ contract RollupCore is
     uint256 blockNumber = ++rollupStore.tips.pendingBlockNumber;
 
     {
-      rollupStore.blocks[blockNumber] = _toBlockLog(_args, blockNumber, components.congestionCost);
+      // @note The components are measured in the fee asset.
+      rollupStore.blocks[blockNumber] =
+        _toBlockLog(_args, blockNumber, components.congestionCost, components.provingCost);
     }
 
     rollupStore.blobPublicInputsHashes[blockNumber] = blobPublicInputsHash;
@@ -729,11 +726,12 @@ contract RollupCore is
   }
 
   // Helper to avoid stack too deep
-  function _toBlockLog(ProposeArgs calldata _args, uint256 _blockNumber, uint256 _congestionCost)
-    internal
-    view
-    returns (BlockLog memory)
-  {
+  function _toBlockLog(
+    ProposeArgs calldata _args,
+    uint256 _blockNumber,
+    uint256 _congestionCost,
+    uint256 _provingCost
+  ) internal view returns (BlockLog memory) {
     FeeHeader memory parentFeeHeader = rollupStore.blocks[_blockNumber - 1].feeHeader;
     return BlockLog({
       archive: _args.archive,
@@ -745,7 +743,8 @@ contract RollupCore is
           _args.oracleInput.feeAssetPriceModifier
         ),
         manaUsed: uint256(bytes32(_args.header[0x0268:0x0288])),
-        congestionCost: _congestionCost
+        congestionCost: _congestionCost,
+        provingCost: _provingCost
       })
     });
   }

l1-contracts/src/core/libraries/RollupLibs/FeeMath.sol

@@ -37,9 +37,10 @@ struct ManaBaseFeeComponents {
 
 struct FeeHeader {
   uint256 excessMana;
-  uint256 feeAssetPriceNumerator;
   uint256 manaUsed;
+  uint256 feeAssetPriceNumerator;
   uint256 congestionCost;
+  uint256 provingCost;
 }
 
 struct L1FeeData {

l1-contracts/test/Rollup.t.sol

@@ -346,6 +346,28 @@ contract RollupTest is RollupBase {
     rollup.propose(args, signatures, data.body, data.blobInputs);
   }
 
+  function testProvingFeeUpdates() public setUpFor("mixed_block_1") {
+    rollup.setProvingCostPerMana(EthValue.wrap(1000));
+    _proposeBlock("mixed_block_1", 1, 1e6);
+
+    rollup.setProvingCostPerMana(EthValue.wrap(2000));
+    _proposeBlock("mixed_block_2", 2, 1e6);
+
+    // At this point in time, we have had different proving costs for the two blocks. When we prove them
+    // in the same epoch, we want to see that the correct fee is taken for each block.
+    _proveBlocks("mixed_block_", 1, 2, address(this));
+
+    // 1e6 mana at 1000 and 2000 cost per manage multiplied by 10 for the price conversion to fee asset.
+    uint256 provingFees = 1e6 * (1000 + 2000) * 10;
+    uint256 expectedProverRewards = rewardDistributor.BLOCK_REWARD() / 2 * 2 + provingFees;
+
+    assertEq(
+      rollup.getCollectiveProverRewardsForEpoch(Epoch.wrap(0)),
+      expectedProverRewards,
+      "invalid prover rewards"
+    );
+  }
+
   struct TestBlockFeeStruct {
     EthValue provingCostPerManaInEth;
     FeeAssetValue provingCostPerManaInFeeAsset;

l1-contracts/test/fees/MinimalFeeModel.sol

@@ -56,7 +56,7 @@ contract MinimalFeeModel {
   EthValue public provingCost = EthValue.wrap(100);
 
   constructor(uint256 _slotDuration, uint256 _epochDuration) {
-    feeHeaders[0] = FeeHeader(0, 0, 0, 0);
+    feeHeaders[0] = FeeHeader(0, 0, 0, 0, 0);
 
     l1BaseFees.pre = L1FeesModel({base_fee: 1 gwei, blob_fee: 1});
     l1BaseFees.post = L1FeesModel({base_fee: block.basefee, blob_fee: _getBlobBaseFee()});
@@ -127,7 +127,8 @@ contract MinimalFeeModel {
       ),
       manaUsed: _manaUsed,
       excessMana: excessMana,
-      congestionCost: 0
+      congestionCost: 0,
+      provingCost: 0
     });
   }
 

yarn-project/aztec.js/src/api/ethereum/cheat_codes.ts

@@ -143,7 +143,7 @@ export class RollupCheatCodes {
 
     const tipsAfter = await this.getTips();
     this.logger.info(
-      `Proven tip moved: ${tipsBefore.proven} -> ${tipsAfter.proven}. Pending tip moved: ${tipsBefore.pending} -> ${tipsAfter.pending}`,
+      `Proven tip moved: ${tipsBefore.proven} -> ${tipsAfter.proven}. Pending tip: ${tipsAfter.pending}.`,
     );
   }