From 6dd14e4f4f744189702802981b466f10332a4c9a Mon Sep 17 00:00:00 2001
From: Jamie Lokier <jamie@shareable.org>
Date: Mon, 3 May 2021 09:07:56 +0100
Subject: [PATCH] GraphQL: Move EVM-calling function makeCall to rpcMakeCall

`makeCall` used by GraphQL is another way to setup and call the EVM.
Move it to `transaction/call_evm`.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
---
 nimbus/graphql/ethapi.nim       | 17 ++++-------------
 nimbus/transaction/call_evm.nim | 15 ++++++++++++++-
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/nimbus/graphql/ethapi.nim b/nimbus/graphql/ethapi.nim
index f38969158..27e4e5981 100644
--- a/nimbus/graphql/ethapi.nim
+++ b/nimbus/graphql/ethapi.nim
@@ -746,20 +746,11 @@ proc toCallData(n: Node): (RpcCallData, bool) =
   (cd, gasLimit)
 
 proc makeCall(ctx: GraphqlContextRef, callData: RpcCallData, header: BlockHeader, chainDB: BaseChainDB): RespResult =
-  # TODO: handle revert
-  var
-    # we use current header stateRoot, unlike block validation
-    # which use previous block stateRoot
-    vmState = newBaseVMState(header.stateRoot, header, chainDB)
-    fork    = toFork(chainDB.config, header.blockNumber)
-    comp    = rpcSetupComputation(vmState, callData, fork)
-
-  let gas = comp.gasMeter.gasRemaining
-  comp.execComputation()
+  let (outputHex, gasUsed, isError) = rpcMakeCall(callData, header, chainDB)
   var map = respMap(ctx.ids[ethCallResult])
-  map["data"]    = resp("0x" & comp.output.toHex)
-  map["gasUsed"] = longNode(gas - comp.gasMeter.gasRemaining).get()
-  map["status"]  = longNode(if comp.isError: 0 else: 1).get()
+  map["data"]    = resp("0x" & outputHex)
+  map["gasUsed"] = longNode(gasUsed).get()
+  map["status"]  = longNode(if isError: 0 else: 1).get()
   ok(map)
 
 proc blockCall(ud: RootRef, params: Args, parent: Node): RespResult {.apiPragma.} =
diff --git a/nimbus/transaction/call_evm.nim b/nimbus/transaction/call_evm.nim
index ae67767b6..3756f6aca 100644
--- a/nimbus/transaction/call_evm.nim
+++ b/nimbus/transaction/call_evm.nim
@@ -7,7 +7,7 @@
 # at your option. This file may not be copied, modified, or distributed except according to those terms.
 
 import
-  eth/common/eth_types, stint, options,
+  eth/common/eth_types, stint, options, stew/byteutils,
   ".."/[vm_types, vm_types2, vm_state, vm_computation],
   ".."/[db/db_chain, config, vm_state_transactions, rpc/hexstrings],
   ".."/[db/accounts_cache, p2p/executor], eth/trie/db
@@ -55,6 +55,19 @@ proc rpcDoCall*(call: RpcCallData, header: BlockHeader, chain: BaseChainDB): Hex
   comp.execComputation()
   result = hexDataStr(comp.output)
 
+proc rpcMakeCall*(call: RpcCallData, header: BlockHeader, chain: BaseChainDB): (string, GasInt, bool) =
+  # TODO: handle revert
+  var
+    # we use current header stateRoot, unlike block validation
+    # which use previous block stateRoot
+    vmState = newBaseVMState(header.stateRoot, header, chain)
+    fork    = toFork(chain.config, header.blockNumber)
+    comp    = rpcSetupComputation(vmState, call, fork)
+
+  let gas = comp.gasMeter.gasRemaining
+  comp.execComputation()
+  return (comp.output.toHex, gas - comp.gasMeter.gasRemaining, comp.isError)
+
 proc rpcEstimateGas*(call: RpcCallData, header: BlockHeader, chain: BaseChainDB, haveGasLimit: bool): GasInt =
   # TODO: handle revert and error
   var