From 98464ca46329e3b3a8190eb47def387f5540fd6a Mon Sep 17 00:00:00 2001
From: philip-morlier <philipmorlier@gmail.com>
Date: Wed, 28 Feb 2024 20:37:17 -0800
Subject: [PATCH] Further changes to enable the shanghai fork as well as
 redefining the random opcode

---
 core/vm/interpreter.go | 9 ++++++++-
 params/config.go       | 6 +++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/core/vm/interpreter.go b/core/vm/interpreter.go
index f34c082eb..1c175baf6 100644
--- a/core/vm/interpreter.go
+++ b/core/vm/interpreter.go
@@ -60,6 +60,11 @@ func NewEVMInterpreter(evm *EVM) *EVMInterpreter {
 		table = &cancunInstructionSet
 	case evm.chainRules.IsShanghai:
 		table = &shanghaiInstructionSet
+		// begin PluGeth injection
+		if !evm.chainRules.IsMerge {
+			table[RANDOM] = frontierInstructionSet[DIFFICULTY]
+		}
+		// end PluGeth injection
 	case evm.chainRules.IsMerge:
 		table = &mergeInstructionSet
 	case evm.chainRules.IsLondon:
@@ -72,10 +77,12 @@ func NewEVMInterpreter(evm *EVM) *EVMInterpreter {
 		table = &constantinopleInstructionSet
 	case evm.chainRules.IsByzantium:
 		table = &byzantiumInstructionSet
+
 	// begin PluGeth injection
 	case evm.chainRules.IsEIP160:
-	// end PluGeth injection
 		table = &spuriousDragonInstructionSet
+	// end PluGeth injection
+	
 	case evm.chainRules.IsEIP150:
 		table = &tangerineWhistleInstructionSet
 	case evm.chainRules.IsHomestead:
diff --git a/params/config.go b/params/config.go
index f31f4f98c..9c4958569 100644
--- a/params/config.go
+++ b/params/config.go
@@ -933,7 +933,11 @@ func (c *ChainConfig) Rules(num *big.Int, isMerge bool, timestamp uint64) Rules
 		IsBerlin:         c.IsBerlin(num),
 		IsLondon:         c.IsLondon(num),
 		IsMerge:          isMerge,
-		IsShanghai:       isMerge && c.IsShanghai(num, timestamp),
+		// IsShanghai:       isMerge && c.IsShanghai(num, timestamp),
+		// the above is being commented and replaced with the plugeth code below to hotwire the chainrules to allow shanghai without the merge
+		// begin PluGeth injection
+		IsShanghai:       c.IsShanghai(num, timestamp),
+		// end PluGeth injection
 		IsCancun:         isMerge && c.IsCancun(num, timestamp),
 		IsPrague:         isMerge && c.IsPrague(num, timestamp),
 		IsVerkle:         isMerge && c.IsVerkle(num, timestamp),