accounts/abi: generic unpacking of event logs into map[string]interface{} (#18440)

Add methods that allow for the unpacking of event logs into maps (allows for agnostic unpacking of logs)

accounts/abi/argument.go

@@ -102,6 +102,16 @@ func (arguments Arguments) Unpack(v interface{}, data []byte) error {
 	return arguments.unpackAtomic(v, marshalledValues[0])
 }
 
+// UnpackIntoMap performs the operation hexdata -> mapping of argument name to argument value
+func (arguments Arguments) UnpackIntoMap(v map[string]interface{}, data []byte) error {
+	marshalledValues, err := arguments.UnpackValues(data)
+	if err != nil {
+		return err
+	}
+
+	return arguments.unpackIntoMap(v, marshalledValues)
+}
+
 // unpack sets the unmarshalled value to go format.
 // Note the dst here must be settable.
 func unpack(t *Type, dst interface{}, src interface{}) error {
@@ -160,6 +170,19 @@ func unpack(t *Type, dst interface{}, src interface{}) error {
 	return nil
 }
 
+// unpackIntoMap unpacks marshalledValues into the provided map[string]interface{}
+func (arguments Arguments) unpackIntoMap(v map[string]interface{}, marshalledValues []interface{}) error {
+	// Make sure map is not nil
+	if v == nil {
+		return fmt.Errorf("abi: cannot unpack into a nil map")
+	}
+
+	for i, arg := range arguments.NonIndexed() {
+		v[arg.Name] = marshalledValues[i]
+	}
+	return nil
+}
+
 // unpackAtomic unpacks ( hexdata -> go ) a single value
 func (arguments Arguments) unpackAtomic(v interface{}, marshalledValues interface{}) error {
 	if arguments.LengthNonIndexed() == 0 {