completing 'PrevRandao Opcode Transactions' test case in engine api test

hive_integration/nodocker/engine/engine_tests.nim

@@ -1421,7 +1421,7 @@ proc sendTx(t: TestEnv): Future[void] {.async.} =
   let
     client = t.rpcClient
     clMock = t.clMock
-    period = chronos.milliseconds(100)
+    period = chronos.milliseconds(500)
 
   while not clMock.ttdReached:
     await sleepAsync(period)
@@ -1474,6 +1474,55 @@ proc prevRandaoOpcodeTx(t: TestEnv): TestStatus =
         expect=2,
         get=opcodeValueAtBlock
 
+  # Send transactions now past TTD, the value of the storage in these blocks must match the prevRandao value
+  type
+    ShadowTx = ref object
+      currentTxIndex: int
+      txs: seq[Transaction]
+
+  let shadow = ShadowTx(currentTxIndex: 0)
+
+  let produceBlockRes = clMock.produceBlocks(1, BlockProcessCallbacks(
+    onPayloadProducerSelected: proc(): bool =
+      let
+        tx = t.makeNextTransaction(prevRandaoContractAddr, 0.u256)
+        rr = client.sendTransaction(tx)
+
+      if rr.isErr:
+        error "Unable to send transaction", msg=rr.error
+        return false
+
+      shadow.txs.add tx
+      inc shadow.currentTxIndex
+      return true
+    ,
+    onForkchoiceBroadcast: proc(): bool =
+      # Check the transaction tracing, which is client specific
+      let expectedPrevRandao = clMock.prevRandaoHistory[clMock.latestHeadNumber + 1'u64]
+      let res = debugPrevRandaoTransaction(client, shadow.txs[shadow.currentTxIndex-1], expectedPrevRandao)
+      if res.isErr:
+        error "unable to debug prev randao", msg=res.error
+        return false
+      return true
+  ))
+
+  let rr = client.blockNumber()
+  testCond rr.isOk:
+    error "Unable to get latest block number"
+
+  let lastBlockNumber = rr.get()
+  for i in ttdBlockNumber + 1 ..< lastBlockNumber:
+    let expectedPrevRandao = UInt256.fromBytesBE(clMock.prevRandaoHistory[i].data)
+    let storageKey = i.u256
+
+    let rz = client.storageAt(prevRandaoContractAddr, storageKey)
+    testCond rz.isOk:
+      error "Unable to get storage", msg=rz.error
+
+    let storage = rz.get()
+    testCond storage == expectedPrevRandao:
+      error "Unexpected storage", expected=expectedPrevRandao.toHex, get=storage.toHex
+
 proc postMergeSync(t: TestEnv): TestStatus =
   result = TestStatus.SKIPPED
   # TODO: need multiple client
@@ -1612,11 +1661,11 @@ const engineTestList* = [
 
   # Eth RPC Status on ForkchoiceUpdated Events
 
-  TestSpec(
+  TestSpec( # TODO: fix/debug
     name: "Latest Block after NewPayload",
     run:  blockStatusExecPayload1,
   ),
-  TestSpec(
+  TestSpec( # TODO: fix/debug
     name: "Latest Block after NewPayload (Transition Block)",
     run:  blockStatusExecPayload2,
     ttd:  5,
@@ -1691,7 +1740,6 @@ const engineTestList* = [
     run:  suggestedFeeRecipient,
   ),
 
-  # TODO: debug and fix
   # PrevRandao opcode tests
   TestSpec(
     name: "PrevRandao Opcode Transactions",

hive_integration/nodocker/engine/helper.nim

@@ -1,7 +1,10 @@
 import
-  std/typetraits,
+  std/[typetraits, json, strutils],
   test_env,
-  eth/rlp
+  eth/rlp,
+  stew/byteutils,
+  json_rpc/rpcclient,
+  ../../../nimbus/rpc/hexstrings
 
 type
   ExecutableData* = object
@@ -144,3 +147,41 @@ proc toExecutableData*(payload: ExecutionPayloadV1): ExecutableData =
   for data in payload.transactions:
     let tx = rlp.decode(distinctBase data, Transaction)
     result.transactions.add tx
+
+proc debugPrevRandaoTransaction*(client: RpcClient, tx: Transaction, expectedPrevRandao: Hash256): Result[void, string] =
+  try:
+    let hash = tx.rlpHash
+    # we only interested in stack, disable all other elems
+    let opts = %* {
+      "disableStorage": true,
+      "disableMemory": true,
+      "disableState": true,
+      "disableStateDiff": true
+    }
+
+    let res = waitFor client.call("debug_traceTransaction", %[%hash, opts])
+    let structLogs = res["structLogs"]
+
+    var prevRandaoFound = false
+    for i, x in structLogs.elems:
+      let op = x["op"].getStr
+      if op != "DIFFICULTY": continue
+
+      if i+1 >= structLogs.len:
+        return err("No information after PREVRANDAO operation")
+
+      prevRandaoFound = true
+      let stack = structLogs[i+1]["stack"]
+      if stack.len < 1:
+        return err("Invalid stack after PREVRANDAO operation")
+
+      let stackHash = Hash256(data: hextoByteArray[32](stack[0].getStr))
+      if stackHash != expectedPrevRandao:
+        return err("Invalid stack after PREVRANDAO operation $1 != $2" % [stackHash.data.toHex, expectedPrevRandao.data.toHex])
+
+    if not prevRandaoFound:
+      return err("PREVRANDAO opcode not found")
+
+    ok()
+  except ValueError as e:
+    err(e.msg)

hive_integration/nodocker/engine/test_env.nim

@@ -18,6 +18,7 @@ import
     db/db_chain,
     rpc/p2p,
     rpc/engine_api,
+    rpc/debug,
     sync/protocol,
     utils/tx_pool
   ],
@@ -93,6 +94,7 @@ proc setupELClient*(t: TestEnv) =
 
   setupEthRpc(t.ethNode, t.ctx, t.chainDB, txPool, t.rpcServer)
   setupEngineAPI(t.sealingEngine, t.rpcServer)
+  setupDebugRpc(t.chainDB, t.rpcServer)
 
   t.sealingEngine.start()
   t.rpcServer.start()
@@ -155,6 +157,5 @@ proc verifyPoWProgress*(t: TestEnv, lastBlockHash: Hash256): bool =
   if res.isErr:
     error "verify PoW Progress error", msg=res.error
     return false
-    
+
   true
-