eth/tracers: simplify test framework

eth/tracers/internal/tracetest/calltrace_test.go

@@ -144,17 +144,21 @@ func testCallTracer(tracerName string, dirPath string, t *testing.T) {
 			if err != nil {
 				t.Fatalf("failed to retrieve trace result: %v", err)
 			}
-			ret := new(callTrace)
-			if err := json.Unmarshal(res, ret); err != nil {
-				t.Fatalf("failed to unmarshal trace result: %v", err)
+			// The legacy javascript calltracer marshals json in js, which
+			// is not deterministic (as opposed to the golang json encoder).
+			{
+				// This is a tweak to make it deterministic. Can be removed when
+				// we remove the legacy tracer.
+				var x callTrace
+				json.Unmarshal(res, &x)
+				res, _ = json.Marshal(x)
 			}
-
-			if !jsonEqual(ret, test.Result, new(callTrace), new(callTrace)) {
-				// 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)
+			want, err := json.Marshal(test.Result)
+			if err != nil {
+				t.Fatalf("failed to marshal test: %v", err)
+			}
+			if string(want) != string(res) {
+				t.Fatalf("trace mismatch\n have: %v\n want: %v\n", string(res), string(want))
 			}
 		})
 	}
@@ -298,14 +302,9 @@ func TestZeroValueToNotExitCall(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to retrieve trace result: %v", err)
 	}
-	have := new(callTrace)
-	if err := json.Unmarshal(res, have); err != nil {
-		t.Fatalf("failed to unmarshal trace result: %v", err)
-	}
-	wantStr := `{"type":"CALL","from":"0x682a80a6f560eec50d54e63cbeda1c324c5f8d1b","to":"0x00000000000000000000000000000000deadbeef","value":"0x0","gas":"0x7148","gasUsed":"0x2d0","input":"0x","output":"0x","calls":[{"type":"CALL","from":"0x00000000000000000000000000000000deadbeef","to":"0x00000000000000000000000000000000000000ff","value":"0x0","gas":"0x6cbf","gasUsed":"0x0","input":"0x","output":"0x"}]}`
-	want := new(callTrace)
-	json.Unmarshal([]byte(wantStr), want)
-	if !jsonEqual(have, want, new(callTrace), new(callTrace)) {
-		t.Error("have != want")
+	wantStr := `{"from":"0x682a80a6f560eec50d54e63cbeda1c324c5f8d1b","gas":"0x7148","gasUsed":"0x2d0","to":"0x00000000000000000000000000000000deadbeef","input":"0x","calls":[{"from":"0x00000000000000000000000000000000deadbeef","gas":"0x6cbf","gasUsed":"0x0","to":"0x00000000000000000000000000000000000000ff","input":"0x","value":"0x0","type":"CALL"}],"value":"0x0","type":"CALL"}`
+	//want := new(callTrace)
+	if string(res) != wantStr {
+		t.Fatalf("trace mismatch\n have: %v\n want: %v\n", string(res), wantStr)
 	}
 }

eth/tracers/internal/tracetest/prestate_test.go

@@ -33,21 +33,8 @@ import (
 	"github.com/ethereum/go-ethereum/tests"
 )
 
-// prestateTrace is the result of a prestateTrace run.
-type prestateTrace = map[common.Address]*account
-type account struct {
-	Balance string                      `json:"balance,omitempty"`
-	Nonce   uint64                      `json:"nonce,omitempty"`
-	Code    string                      `json:"code,omitempty"`
-	Storage map[common.Hash]common.Hash `json:"storage,omitempty"`
-}
-type prePostStateTrace struct {
-	Pre  prestateTrace `json:"pre"`
-	Post prestateTrace `json:"post"`
-}
-
-// prestateTraceTest defines a single test to check the stateDiff tracer against.
-type prestateTraceTest struct {
+// testcase defines a single test to check the stateDiff tracer against.
+type testcase struct {
 	Genesis      *core.Genesis   `json:"genesis"`
 	Context      *callContext    `json:"context"`
 	Input        string          `json:"input"`
@@ -56,14 +43,14 @@ type prestateTraceTest struct {
 }
 
 func TestPrestateTracer(t *testing.T) {
-	testPrestateDiffTracer("prestateTracer", "prestate_tracer", t, func() interface{} { return new(prestateTrace) })
+	testPrestateDiffTracer("prestateTracer", "prestate_tracer", t)
 }
 
 func TestPrestateWithDiffModeTracer(t *testing.T) {
-	testPrestateDiffTracer("prestateTracer", "prestate_tracer_with_diff_mode", t, func() interface{} { return new(prePostStateTrace) })
+	testPrestateDiffTracer("prestateTracer", "prestate_tracer_with_diff_mode", t)
 }
 
-func testPrestateDiffTracer(tracerName string, dirPath string, t *testing.T, typeBuilder func() interface{}) {
+func testPrestateDiffTracer(tracerName string, dirPath string, t *testing.T) {
 	files, err := os.ReadDir(filepath.Join("testdata", dirPath))
 	if err != nil {
 		t.Fatalf("failed to retrieve tracer test suite: %v", err)
@@ -77,7 +64,7 @@ func testPrestateDiffTracer(tracerName string, dirPath string, t *testing.T, typ
 			t.Parallel()
 
 			var (
-				test = new(prestateTraceTest)
+				test = new(testcase)
 				tx   = new(types.Transaction)
 			)
 			// Call tracer test found, read if from disk
@@ -127,17 +114,12 @@ func testPrestateDiffTracer(tracerName string, dirPath string, t *testing.T, typ
 			if err != nil {
 				t.Fatalf("failed to retrieve trace result: %v", err)
 			}
-			ret := typeBuilder()
-			if err := json.Unmarshal(res, ret); err != nil {
-				t.Fatalf("failed to unmarshal trace result: %v", err)
+			want, err := json.Marshal(test.Result)
+			if err != nil {
+				t.Fatalf("failed to marshal test: %v", err)
 			}
-
-			if !jsonEqual(ret, test.Result, typeBuilder(), typeBuilder()) {
-				// 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)
+			if string(want) != string(res) {
+				t.Fatalf("trace mismatch\n have: %v\n want: %v\n", string(res), string(want))
 			}
 		})
 	}

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

@@ -77,8 +77,7 @@
       "nonce": 29072
     },
     "0x1585936b53834b021f68cc13eeefdec2efc8e724": {
-      "balance": "0x0",
-      "nonce": 0
+      "balance": "0x0"
     }
   }
 }

eth/tracers/internal/tracetest/util.go

@@ -1,8 +1,6 @@
 package tracetest
 
 import (
-	"encoding/json"
-	"reflect"
 	"strings"
 	"unicode"
 
@@ -64,22 +62,6 @@ var makeTest = function(tx, rewind) {
 }
 */
 
-// jsonEqual is similar to reflect.DeepEqual, but does a 'bounce' via json prior to
-// comparison
-func jsonEqual(xi, yi, xt, yt interface{}) bool {
-	if xj, err := json.Marshal(xi); err == nil {
-		json.Unmarshal(xj, xt)
-	} else {
-		return false
-	}
-	if yj, err := json.Marshal(yi); err == nil {
-		json.Unmarshal(yj, yt)
-	} else {
-		return false
-	}
-	return reflect.DeepEqual(xt, yt)
-}
-
 // camel converts a snake cased input string into a camel cased output.
 func camel(str string) string {
 	pieces := strings.Split(str, "_")

eth/tracers/js/internal/tracers/call_tracer_legacy.js

@@ -204,7 +204,6 @@
 			gasUsed: '0x' + bigInt(ctx.gasUsed).toString(16),
 			input:   toHex(ctx.input),
 			output:  toHex(ctx.output),
-			time:    ctx.time,
 		};
 		if (this.callstack[0].calls !== undefined) {
 			result.calls = this.callstack[0].calls;

eth/tracers/native/prestate.go

@@ -40,8 +40,8 @@ type state = map[common.Address]*account
 
 type account struct {
 	Balance *big.Int                    `json:"balance,omitempty"`
-	Nonce   uint64                      `json:"nonce,omitempty"`
 	Code    []byte                      `json:"code,omitempty"`
+	Nonce   uint64                      `json:"nonce,omitempty"`
 	Storage map[common.Hash]common.Hash `json:"storage,omitempty"`
 }
 
@@ -244,9 +244,9 @@ func (t *prestateTracer) GetResult() (json.RawMessage, error) {
 	var err error
 	if t.config.DiffMode {
 		res, err = json.Marshal(struct {
-			Pre  state `json:"pre"`
 			Post state `json:"post"`
-		}{t.pre, t.post})
+			Pre  state `json:"pre"`
+		}{t.post, t.pre})
 	} else {
 		res, err = json.Marshal(t.pre)
 	}