From 0c1236756dd373c73ad7d3efbdc84397667b7515 Mon Sep 17 00:00:00 2001
From: jangko <jangko128@gmail.com>
Date: Wed, 16 Aug 2023 20:05:43 +0700
Subject: [PATCH] EIP-4895: add withdrawal processing in txpool

---
 nimbus/core/executor/process_block.nim     |  9 +--------
 nimbus/core/tx_pool/tx_chain.nim           |  2 +-
 nimbus/core/tx_pool/tx_tasks/tx_packer.nim |  7 ++++++-
 nimbus/utils/utils.nim                     | 12 ++++++++----
 4 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/nimbus/core/executor/process_block.nim b/nimbus/core/executor/process_block.nim
index 80fa7b85e..3eee76278 100644
--- a/nimbus/core/executor/process_block.nim
+++ b/nimbus/core/executor/process_block.nim
@@ -9,7 +9,7 @@
 # according to those terms.
 
 import
-  math,
+  ../../utils/utils,
   ../../common/common,
   ../../constants,
   ../../db/accounts_cache,
@@ -28,13 +28,6 @@ import
 
 {.push raises: [].}
 
-# ------------------------------------------------------------------------------
-# Private functions
-# ------------------------------------------------------------------------------
-
-func gwei(n: uint64): UInt256 =
-  n.u256 * (10 ^ 9).u256
-
 # Factored this out of procBlkPreamble so that it can be used directly for
 # stateless execution of specific transactions.
 proc processTransactions*(vmState: BaseVMState;
diff --git a/nimbus/core/tx_pool/tx_chain.nim b/nimbus/core/tx_pool/tx_chain.nim
index ffa6ad51a..d81cc6a2c 100644
--- a/nimbus/core/tx_pool/tx_chain.nim
+++ b/nimbus/core/tx_pool/tx_chain.nim
@@ -311,7 +311,7 @@ proc vmState*(dh: TxChainRef): BaseVMState =
 
 proc withdrawals*(dh: TxChainRef): seq[Withdrawal] =
   ## Getter, `BaseVmState` descriptor based on the current insertion point.
-  result = system.move(dh.withdrawals)
+  dh.withdrawals
 
 # ------------------------------------------------------------------------------
 # Public functions, setters
diff --git a/nimbus/core/tx_pool/tx_tasks/tx_packer.nim b/nimbus/core/tx_pool/tx_tasks/tx_packer.nim
index f601b643b..6536b7196 100644
--- a/nimbus/core/tx_pool/tx_tasks/tx_packer.nim
+++ b/nimbus/core/tx_pool/tx_tasks/tx_packer.nim
@@ -20,6 +20,7 @@ import
   stew/sorted_set,
   ../../../db/[accounts_cache, core_db],
   ../../../common/common,
+  ../../../utils/utils,
   "../.."/[dao, executor, validate, eip4844],
   ../../../transaction/call_evm,
   ../../../transaction,
@@ -92,7 +93,6 @@ proc runTx(pst: TxPackerStateRef; item: TxItemRef): GasInt
   pst.cleanState = false
   doAssert 0 <= result
 
-
 proc runTxCommit(pst: TxPackerStateRef; item: TxItemRef; gasBurned: GasInt)
     {.gcsafe,raises: [CatchableError].} =
   ## Book keeping after executing argument `item` transaction in the VM. The
@@ -219,6 +219,11 @@ proc vmExecCommit(pst: TxPackerStateRef)
     xp = pst.xp
     vmState = xp.chain.vmState
 
+  # EIP-4895
+  if xp.chain.nextFork >= FkShanghai:
+    for withdrawal in xp.chain.withdrawals:
+      vmState.stateDB.addBalance(withdrawal.address, withdrawal.amount.gwei)
+
   # EIP-3675: no reward for miner in POA/POS
   if vmState.com.consensus == ConsensusType.POW:
     let
diff --git a/nimbus/utils/utils.nim b/nimbus/utils/utils.nim
index b71efebed..8ac6c1963 100644
--- a/nimbus/utils/utils.nim
+++ b/nimbus/utils/utils.nim
@@ -1,4 +1,5 @@
 import
+  std/math,
   eth/[rlp, common/eth_types_rlp],
   stew/byteutils,
   ../db/core_db
@@ -65,8 +66,8 @@ proc short*(h: Hash256): string =
   bytes[^3..^1] = h.data[^3..^1]
   bytes.toHex
 
-proc decompose*(rlp: var Rlp, 
-                header: var BlockHeader, 
+proc decompose*(rlp: var Rlp,
+                header: var BlockHeader,
                 body: var BlockBody) {.gcsafe, raises: [RlpError].} =
   var blk = rlp.read(EthBlock)
   header = system.move(blk.header)
@@ -74,8 +75,11 @@ proc decompose*(rlp: var Rlp,
   body.uncles = system.move(blk.uncles)
   body.withdrawals = system.move(blk.withdrawals)
 
-proc decompose*(rlpBytes: openArray[byte], 
-                header: var BlockHeader, 
+proc decompose*(rlpBytes: openArray[byte],
+                header: var BlockHeader,
                 body: var BlockBody) {.gcsafe, raises: [RlpError].} =
   var rlp = rlpFromBytes(rlpBytes)
   rlp.decompose(header, body)
+
+func gwei*(n: uint64): UInt256 =
+  n.u256 * (10 ^ 9).u256