feat: Waku v2 bridge

Issue #12610

vendor/github.com/anacrolix/missinggo/empty_value.go

@@ -0,0 +1,33 @@
+package missinggo
+
+import "reflect"
+
+func IsZeroValue(i interface{}) bool {
+	return IsEmptyValue(reflect.ValueOf(i))
+}
+
+// Returns whether the value represents the empty value for its type. Used for
+// example to determine if complex types satisfy the common "omitempty" tag
+// option for marshalling. Taken from
+// http://stackoverflow.com/a/23555352/149482.
+func IsEmptyValue(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Func, reflect.Map, reflect.Slice:
+		return v.IsNil()
+	case reflect.Array:
+		z := true
+		for i := 0; i < v.Len(); i++ {
+			z = z && IsEmptyValue(v.Index(i))
+		}
+		return z
+	case reflect.Struct:
+		z := true
+		for i := 0; i < v.NumField(); i++ {
+			z = z && IsEmptyValue(v.Field(i))
+		}
+		return z
+	}
+	// Compare other types directly:
+	z := reflect.Zero(v.Type())
+	return v.Interface() == z.Interface()
+}