fix: add name for MethodMeta (#5387)

Author: simlecode

venus-shared/utils/method_map.go

@@ -2,7 +2,9 @@ package utils
 
 import (
 	"reflect"
+	"runtime"
 	"strconv"
+	"strings"
 
 	"github.com/filecoin-project/go-state-types/abi"
 	actorstypes "github.com/filecoin-project/go-state-types/actors"
@@ -19,7 +21,8 @@ import (
 )
 
 type MethodMeta struct {
-	Num string
+	Num  string
+	Name string
 
 	Params reflect.Type
 	Ret    reflect.Type
@@ -75,6 +78,7 @@ func loadMethodsMap() {
 			// Explicitly add send, it's special.
 			methods[builtin.MethodSend] = MethodMeta{
 				Num:    "0",
+				Name:   "Send",
 				Params: reflect.TypeOf(new(abi.EmptyValue)),
 				Ret:    reflect.TypeOf(new(abi.EmptyValue)),
 			}
@@ -89,11 +93,33 @@ func loadMethodsMap() {
 				ev := reflect.ValueOf(export)
 				et := ev.Type()
 
-				methods[abi.MethodNum(number)] = MethodMeta{
+				methodMeta := MethodMeta{
 					Num:    strconv.Itoa(int(number)),
 					Params: et.In(1),
 					Ret:    et.Out(0),
 				}
+
+				// if actor version grater than Version8, we could not get method name.
+				// venus-wallet need `fnName`
+				if awv.av < actorstypes.Version8 {
+					// Extract the method names using reflection. These
+					// method names always match the field names in the
+					// `builtin.Method*` structs (tested in the specs-actors
+					// tests).
+					fnName := runtime.FuncForPC(ev.Pointer()).Name()
+					fnName = strings.TrimSuffix(fnName[strings.LastIndexByte(fnName, '.')+1:], "-fm")
+
+					switch abi.MethodNum(number) {
+					case builtin.MethodSend:
+						panic("method 0 is reserved for Send")
+					case builtin.MethodConstructor:
+						if fnName != "Constructor" {
+							panic("method 1 is reserved for Constructor")
+						}
+					}
+					methodMeta.Name = fnName
+				}
+				methods[abi.MethodNum(number)] = methodMeta
 			}
 
 			MethodsMap[actor.Code()] = methods