tests: extend test case util with RANDOM support

Author: MariusVanDerWijden

cmd/evm/internal/t8ntool/execution.go

@@ -66,6 +66,7 @@ type ommer struct {
 type stEnv struct {
 	Coinbase         common.Address                      `json:"currentCoinbase"   gencodec:"required"`
 	Difficulty       *big.Int                            `json:"currentDifficulty"`
+	Random           *big.Int                            `json:"currentRandom"`
 	ParentDifficulty *big.Int                            `json:"parentDifficulty"`
 	GasLimit         uint64                              `json:"currentGasLimit"   gencodec:"required"`
 	Number           uint64                              `json:"currentNumber"     gencodec:"required"`
@@ -80,6 +81,7 @@ type stEnv struct {
 type stEnvMarshaling struct {
 	Coinbase         common.UnprefixedAddress
 	Difficulty       *math.HexOrDecimal256
+	Random           *math.HexOrDecimal256
 	ParentDifficulty *math.HexOrDecimal256
 	GasLimit         math.HexOrDecimal64
 	Number           math.HexOrDecimal64

cmd/evm/internal/t8ntool/gen_stenv.go

@@ -294,7 +294,8 @@ func (g *Genesis) ToBlock(db ethdb.Database) *types.Block {
 	if g.GasLimit == 0 {
 		head.GasLimit = params.GenesisGasLimit
 	}
-	if g.Difficulty == nil {
+	emptyHash := common.Hash{}
+	if g.Difficulty == nil && bytes.Equal(g.Mixhash[:], emptyHash[:]) {
 		head.Difficulty = params.GenesisDifficulty
 	}
 	if g.Config != nil && g.Config.IsLondon(common.Big0) {

core/genesis.go

@@ -80,7 +80,8 @@ type stPostState struct {
 
 type stEnv struct {
 	Coinbase   common.Address `json:"currentCoinbase"   gencodec:"required"`
-	Difficulty *big.Int       `json:"currentDifficulty" gencodec:"required"`
+	Difficulty *big.Int       `json:"currentDifficulty" gencodec:"optional"`
+	Random     *big.Int       `json:"currentRandom" gencodec:"optional"`
 	GasLimit   uint64         `json:"currentGasLimit"   gencodec:"required"`
 	Number     uint64         `json:"currentNumber"     gencodec:"required"`
 	Timestamp  uint64         `json:"currentTimestamp"  gencodec:"required"`
@@ -90,6 +91,7 @@ type stEnv struct {
 type stEnvMarshaling struct {
 	Coinbase   common.UnprefixedAddress
 	Difficulty *math.HexOrDecimal256
+	Random     *math.HexOrDecimal256
 	GasLimit   math.HexOrDecimal64
 	Number     math.HexOrDecimal64
 	Timestamp  math.HexOrDecimal64
@@ -218,8 +220,11 @@ func (t *StateTest) RunNoVerify(subtest StateSubtest, vmconfig vm.Config, snapsh
 	context := core.NewEVMBlockContext(block.Header(), nil, &t.json.Env.Coinbase)
 	context.GetHash = vmTestBlockHash
 	context.BaseFee = baseFee
+	if t.json.Env.Random != nil {
+		context.Random = common.BigToHash(t.json.Env.Random)
+		context.Difficulty = nil
+	}
 	evm := vm.NewEVM(context, txContext, statedb, config, vmconfig)
-
 	// Execute the message.
 	snapshot := statedb.Snapshot()
 	gaspool := new(core.GasPool)
@@ -268,7 +273,7 @@ func MakePreState(db ethdb.Database, accounts core.GenesisAlloc, snapshotter boo
 }
 
 func (t *StateTest) genesis(config *params.ChainConfig) *core.Genesis {
-	return &core.Genesis{
+	genesis := &core.Genesis{
 		Config:     config,
 		Coinbase:   t.json.Env.Coinbase,
 		Difficulty: t.json.Env.Difficulty,
@@ -277,6 +282,12 @@ func (t *StateTest) genesis(config *params.ChainConfig) *core.Genesis {
 		Timestamp:  t.json.Env.Timestamp,
 		Alloc:      t.json.Pre,
 	}
+	if t.json.Env.Random != nil {
+		// Post-Merge
+		genesis.Mixhash = common.BigToHash(t.json.Env.Random)
+		genesis.Difficulty = nil
+	}
+	return genesis
 }
 
 func (tx *stTransaction) toMessage(ps stPostState, baseFee *big.Int) (core.Message, error) {