eth/tracers: flag for empty acounts in prestateTracer (#31855)

This PR introduces a flag that enables returning of newly created state
objects in the prestateTracer.

**Rationale**
Having this information is useful because local execution can more
easily distinguish between newly created objects and system contracts.

---------

Co-authored-by: Sina Mahmoodi <itz.s1na@gmail.com>

Author: nebojsa94

eth/tracers/internal/tracetest/testdata/prestate_tracer/enable_empty.json

@@ -0,0 +1,61 @@
+{
+  "context": {
+    "difficulty": "3755480783",
+    "gasLimit": "5401723",
+    "miner": "0xd049bfd667cb46aa3ef5df0da3e57db3be39e511",
+    "number": "2294702",
+    "timestamp": "1513676146"
+  },
+  "genesis": {
+    "alloc": {
+      "0x13e4acefe6a6700604929946e70e6443e4e73447": {
+        "balance": "0xcf3e0938579f000",
+        "code": "0x",
+        "nonce": "9",
+        "storage": {}
+      }
+    },
+    "config": {
+      "byzantiumBlock": 1700000,
+      "chainId": 3,
+      "daoForkSupport": true,
+      "eip150Block": 0,
+      "eip150Hash": "0x41941023680923e0fe4d74a34bdac8141f2540e3ae90623718e47d66d1ca4a2d",
+      "eip155Block": 10,
+      "eip158Block": 10,
+      "ethash": {},
+      "homesteadBlock": 0
+    },
+    "difficulty": "3757315409",
+    "extraData": "0x566961425443",
+    "gasLimit": "5406414",
+    "hash": "0xae107f592eebdd9ff8d6ba00363676096e6afb0e1007a7d3d0af88173077378d",
+    "miner": "0xd049bfd667cb46aa3ef5df0da3e57db3be39e511",
+    "mixHash": "0xc927aa05a38bc3de864e95c33b3ae559d3f39c4ccd51cef6f113f9c50ba0caf1",
+    "nonce": "0x93363bbd2c95f410",
+    "number": "2294701",
+    "stateRoot": "0x6b6737d5bde8058990483e915866bd1578014baeff57bd5e4ed228a2bfad635c",
+    "timestamp": "1513676127"
+  },
+  "input": "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",
+  "tracerConfig": {
+    "includeEmpty": true
+  },
+  "result": {
+    "0x13e4acefe6a6700604929946e70e6443e4e73447": {
+      "balance": "0xcf3e0938579f000",
+      "nonce": 9
+    },
+    "0x7dc9c9730689ff0b0fd506c67db815f12d90a448": {
+      "balance": "0x0",
+      "storage": {
+        "0x0000000000000000000000000000000000000000000000000000000000000000": "0x0000000000000000000000000000000000000000000000000000000000000000",
+        "0x0000000000000000000000000000000000000000000000000000000000000001": "0x0000000000000000000000000000000000000000000000000000000000000000",
+        "0x0000000000000000000000000000000000000000000000000000000000000004": "0x0000000000000000000000000000000000000000000000000000000000000000"
+      }
+    },
+    "0xd049bfd667cb46aa3ef5df0da3e57db3be39e511": {
+      "balance": "0x0"
+    }
+  }
+}

eth/tracers/native/prestate.go

@@ -19,6 +19,7 @@ package native
 import (
 	"bytes"
 	"encoding/json"
+	"errors"
 	"math/big"
 	"sync/atomic"
 
@@ -75,13 +76,19 @@ type prestateTracerConfig struct {
 	DiffMode       bool `json:"diffMode"`       // If true, this tracer will return state modifications
 	DisableCode    bool `json:"disableCode"`    // If true, this tracer will not return the contract code
 	DisableStorage bool `json:"disableStorage"` // If true, this tracer will not return the contract storage
+	IncludeEmpty   bool `json:"includeEmpty"`   // If true, this tracer will return empty state objects
 }
 
 func newPrestateTracer(ctx *tracers.Context, cfg json.RawMessage, chainConfig *params.ChainConfig) (*tracers.Tracer, error) {
 	var config prestateTracerConfig
 	if err := json.Unmarshal(cfg, &config); err != nil {
 		return nil, err
 	}
+	// Diff mode has special semantics around account creating and deletion which
+	// requires it to include empty accounts and storage.
+	if config.DiffMode && config.IncludeEmpty {
+		return nil, errors.New("cannot use diffMode with includeEmpty")
+	}
 	t := &prestateTracer{
 		pre:     stateMap{},
 		post:    stateMap{},
@@ -180,7 +187,7 @@ func (t *prestateTracer) OnTxEnd(receipt *types.Receipt, err error) {
 	// the new created contracts' prestate were empty, so delete them
 	for a := range t.created {
 		// the created contract maybe exists in statedb before the creating tx
-		if s := t.pre[a]; s != nil && s.empty {
+		if s := t.pre[a]; s != nil && s.empty && !t.config.IncludeEmpty {
 			delete(t.pre, a)
 		}
 	}