From 2e8acfd4fa24dfce670e2e2413bd6ed862685f2f Mon Sep 17 00:00:00 2001
From: Quentin Mc Gaw <quentin.mcgaw@avalabs.org>
Date: Tue, 21 Jan 2025 10:32:21 +0100
Subject: [PATCH] Header copy hooks

---
 core/types/header_ext.go | 54 ++++++++++++++++++++++++++++++++++++++++
 go.mod                   |  2 +-
 go.sum                   |  4 +--
 3 files changed, 57 insertions(+), 3 deletions(-)

diff --git a/core/types/header_ext.go b/core/types/header_ext.go
index fe1018ffb1..3accde4469 100644
--- a/core/types/header_ext.go
+++ b/core/types/header_ext.go
@@ -67,6 +67,60 @@ func (h *HeaderExtra) UnmarshalJSON(eth *ethtypes.Header, input []byte) error {
 	return nil
 }
 
+func (h *HeaderExtra) Copy(header *Header) *Header {
+	extraCopy := &HeaderExtra{
+		ExtDataHash: h.ExtDataHash,
+	}
+
+	if h.BlockGasCost != nil {
+		extraCopy.BlockGasCost = big.NewInt(0)
+		extraCopy.BlockGasCost.SetBytes(h.BlockGasCost.Bytes())
+	}
+
+	if h.ExtDataGasUsed != nil {
+		extraCopy.ExtDataGasUsed = big.NewInt(0)
+		extraCopy.ExtDataGasUsed.SetBytes(h.ExtDataGasUsed.Bytes())
+	}
+
+	cpy := copyBaseHeader(header)
+	return WithHeaderExtras(cpy, extraCopy)
+}
+
+// TODO add test to make sure this mirrors copy with a no extra header.
+func copyBaseHeader(h *ethtypes.Header) *ethtypes.Header {
+	cpy := *h
+	if cpy.Difficulty = new(big.Int); h.Difficulty != nil {
+		cpy.Difficulty.Set(h.Difficulty)
+	}
+	if cpy.Number = new(big.Int); h.Number != nil {
+		cpy.Number.Set(h.Number)
+	}
+	if h.BaseFee != nil {
+		cpy.BaseFee = new(big.Int).Set(h.BaseFee)
+	}
+	if len(h.Extra) > 0 {
+		cpy.Extra = make([]byte, len(h.Extra))
+		copy(cpy.Extra, h.Extra)
+	}
+	if h.WithdrawalsHash != nil {
+		cpy.WithdrawalsHash = new(common.Hash)
+		*cpy.WithdrawalsHash = *h.WithdrawalsHash
+	}
+	if h.ExcessBlobGas != nil {
+		cpy.ExcessBlobGas = new(uint64)
+		*cpy.ExcessBlobGas = *h.ExcessBlobGas
+	}
+	if h.BlobGasUsed != nil {
+		cpy.BlobGasUsed = new(uint64)
+		*cpy.BlobGasUsed = *h.BlobGasUsed
+	}
+	if h.ParentBeaconRoot != nil {
+		cpy.ParentBeaconRoot = new(common.Hash)
+		*cpy.ParentBeaconRoot = *h.ParentBeaconRoot
+	}
+	return &cpy
+}
+
 //go:generate go run github.com/fjl/gencodec -type HeaderSerializable -field-override headerMarshaling -out gen_header_json.go
 //go:generate go run github.com/ava-labs/libevm/rlp/rlpgen -type HeaderSerializable -out gen_header_rlp.go
 
diff --git a/go.mod b/go.mod
index b154a246e3..e022dff40e 100644
--- a/go.mod
+++ b/go.mod
@@ -136,4 +136,4 @@ require (
 	rsc.io/tmplfunc v0.0.3 // indirect
 )
 
-replace github.com/ava-labs/libevm => github.com/ava-labs/libevm v0.0.0-20250120102234-7ec5d041c250
+replace github.com/ava-labs/libevm => github.com/ava-labs/libevm v0.0.0-20250121093001-0a85fe10c3ef
diff --git a/go.sum b/go.sum
index 8ab3718fa7..830748ef85 100644
--- a/go.sum
+++ b/go.sum
@@ -58,8 +58,8 @@ github.com/allegro/bigcache v1.2.1-0.20190218064605-e24eb225f156/go.mod h1:Cb/ax
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/ava-labs/avalanchego v1.12.1-0.20250107220127-32f58b4fa9c8 h1:qN3MOBHB//Ynhgt5Vys3iVe42Sr0EWSeN18VL3ecXzE=
 github.com/ava-labs/avalanchego v1.12.1-0.20250107220127-32f58b4fa9c8/go.mod h1:2B7+E5neLvkOr2zursGhebjU26d4AfB7RazPxBs8hHg=
-github.com/ava-labs/libevm v0.0.0-20250120102234-7ec5d041c250 h1:qOWsbdH7Nmv2xS9H2qSfDUVhIzEwMxyzGxSoXZjmYm4=
-github.com/ava-labs/libevm v0.0.0-20250120102234-7ec5d041c250/go.mod h1:M8TCw2g1D5GBB7hu7g1F4aot5bRHGSxnBawNVmHE9Z0=
+github.com/ava-labs/libevm v0.0.0-20250121093001-0a85fe10c3ef h1:hl3X0EmZl7eCRi7wHgK0Qgb6wHXkKI71f63L7NY14p4=
+github.com/ava-labs/libevm v0.0.0-20250121093001-0a85fe10c3ef/go.mod h1:M8TCw2g1D5GBB7hu7g1F4aot5bRHGSxnBawNVmHE9Z0=
 github.com/aymerick/raymond v2.0.3-0.20180322193309-b565731e1464+incompatible/go.mod h1:osfaiScAUVup+UC9Nfq76eWqDhXlp+4UYaA8uhTBO6g=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=