eth/tracers: revert reason in call_tracer + error for failed internal calls (#21387)

* tests: add testdata of call tracer

* eth/tracers: return revert reason in call_tracer

* eth/tracers: regenerate assets

* eth/tracers: add error message even if no exec occurrs, fixes #21438

Co-authored-by: Martin Holst Swende <martin@swende.se>

eth/tracers/internal/tracers/call_tracer.js

@@ -132,13 +132,12 @@
 				// If the call was a contract call, retrieve the gas usage and output
 				if (call.gas !== undefined) {
 					call.gasUsed = '0x' + bigInt(call.gasIn - call.gasCost + call.gas - log.getGas()).toString(16);
-
-					var ret = log.stack.peek(0);
-					if (!ret.equals(0)) {
-						call.output = toHex(log.memory.slice(call.outOff, call.outOff + call.outLen));
-					} else if (call.error === undefined) {
-						call.error = "internal failure"; // TODO(karalabe): surface these faults somehow
-					}
+				}
+				var ret = log.stack.peek(0);
+				if (!ret.equals(0)) {
+					call.output = toHex(log.memory.slice(call.outOff, call.outOff + call.outLen));
+				} else if (call.error === undefined) {
+					call.error = "internal failure"; // TODO(karalabe): surface these faults somehow
 				}
 				delete call.gasIn; delete call.gasCost;
 				delete call.outOff; delete call.outLen;
@@ -208,7 +207,7 @@
 		} else if (ctx.error !== undefined) {
 			result.error = ctx.error;
 		}
-		if (result.error !== undefined) {
+		if (result.error !== undefined && (result.error !== "execution reverted" || result.output ==="0x")) {
 			delete result.output;
 		}
 		return this.finalize(result);

eth/tracers/testdata/call_tracer_inner_instafail.json

@@ -0,0 +1,72 @@
+{
+  "genesis": {
+    "difficulty": "117067574",
+    "extraData": "0xd783010502846765746887676f312e372e33856c696e7578",
+    "gasLimit": "4712380",
+    "hash": "0xe05db05eeb3f288041ecb10a787df121c0ed69499355716e17c307de313a4486",
+    "miner": "0x0c062b329265c965deef1eede55183b3acb8f611",
+    "mixHash": "0xb669ae39118a53d2c65fd3b1e1d3850dd3f8c6842030698ed846a2762d68b61d",
+    "nonce": "0x2b469722b8e28c45",
+    "number": "24973",
+    "stateRoot": "0x532a5c3f75453a696428db078e32ae283c85cb97e4d8560dbdf022adac6df369",
+    "timestamp": "1479891145",
+    "totalDifficulty": "1892250259406",
+    "alloc": {
+      "0x6c06b16512b332e6cd8293a2974872674716ce18": {
+        "balance": "0x0",
+        "nonce": "1",
+        "code": "0x60606040526000357c0100000000000000000000000000000000000000000000000000000000900480632e1a7d4d146036575b6000565b34600057604e60048080359060200190919050506050565b005b3373ffffffffffffffffffffffffffffffffffffffff166108fc829081150290604051809050600060405180830381858888f19350505050505b5056",
+        "storage": {}
+      },
+      "0x66fdfd05e46126a07465ad24e40cc0597bc1ef31": {
+        "balance": "0x229ebbb36c3e0f20",
+        "nonce": "3",
+        "code": "0x",
+        "storage": {}
+      }
+    },
+    "config": {
+      "chainId": 3,
+      "homesteadBlock": 0,
+      "daoForkSupport": true,
+      "eip150Block": 0,
+      "eip150Hash": "0x41941023680923e0fe4d74a34bdac8141f2540e3ae90623718e47d66d1ca4a2d",
+      "eip155Block": 10,
+      "eip158Block": 10,
+      "byzantiumBlock": 1700000,
+      "constantinopleBlock": 4230000,
+      "petersburgBlock": 4939394,
+      "istanbulBlock": 6485846,
+      "muirGlacierBlock": 7117117,
+      "ethash": {}
+    }
+  },
+  "context": {
+    "number": "24974",
+    "difficulty": "117067574",
+    "timestamp": "1479891162",
+    "gasLimit": "4712388",
+    "miner": "0xc822ef32e6d26e170b70cf761e204c1806265914"
+  },
+  "input": "0xf889038504a81557008301f97e946c06b16512b332e6cd8293a2974872674716ce1880a42e1a7d4d00000000000000000000000000000000000000000000000014d1120d7b1600002aa0e2a6558040c5d72bc59f2fb62a38993a314c849cd22fb393018d2c5af3112095a01bdb6d7ba32263ccc2ecc880d38c49d9f0c5a72d8b7908e3122b31356d349745",
+  "result": {
+    "type": "CALL",
+    "from": "0x66fdfd05e46126a07465ad24e40cc0597bc1ef31",
+    "to": "0x6c06b16512b332e6cd8293a2974872674716ce18",
+    "value": "0x0",
+    "gas": "0x1a466",
+    "gasUsed": "0x1dc6",
+    "input": "0x2e1a7d4d00000000000000000000000000000000000000000000000014d1120d7b160000",
+    "output": "0x",
+    "calls": [
+      {
+        "type": "CALL",
+        "from": "0x6c06b16512b332e6cd8293a2974872674716ce18",
+        "to": "0x66fdfd05e46126a07465ad24e40cc0597bc1ef31",
+        "value": "0x14d1120d7b160000",
+        "error":"internal failure",
+        "input": "0x"
+      }
+    ]
+  }
+}

eth/tracers/tracers_test.go

@@ -269,9 +269,31 @@ func TestCallTracer(t *testing.T) {
 				t.Fatalf("failed to unmarshal trace result: %v", err)
 			}
 
-			if !reflect.DeepEqual(ret, test.Result) {
+			if !jsonEqual(ret, test.Result) {
+				// uncomment this for easier debugging
+				//have, _ := json.MarshalIndent(ret, "", " ")
+				//want, _ := json.MarshalIndent(test.Result, "", " ")
+				//t.Fatalf("trace mismatch: \nhave %+v\nwant %+v", string(have), string(want))
 				t.Fatalf("trace mismatch: \nhave %+v\nwant %+v", ret, test.Result)
 			}
 		})
 	}
 }
+
+// jsonEqual is similar to reflect.DeepEqual, but does a 'bounce' via json prior to
+// comparison
+func jsonEqual(x, y interface{}) bool {
+	xTrace := new(callTrace)
+	yTrace := new(callTrace)
+	if xj, err := json.Marshal(x); err == nil {
+		json.Unmarshal(xj, xTrace)
+	} else {
+		return false
+	}
+	if yj, err := json.Marshal(y); err == nil {
+		json.Unmarshal(yj, yTrace)
+	} else {
+		return false
+	}
+	return reflect.DeepEqual(xTrace, yTrace)
+}