fix bug about Reg string

Author: studyzy

container.go

@@ -298,7 +298,7 @@ func (c *Container) invoke(function interface{}, specifiedParameters map[int]int
 	var errPtr *error
 	errType := reflect.TypeOf(errPtr).Elem()
 	for _, rt := range returns {
-		if !rt.IsNil() && rt.Type().Implements(errType) { //返回类型中有不为空的error
+		if rt.Type().Implements(errType) && !rt.IsNil() { //返回类型中有不为空的error
 			return nil, rt.Interface().(error)
 		}
 		returnList = append(returnList, rt.Interface())

container_test.go

@@ -374,3 +374,17 @@ func TestContainer_Clone(t *testing.T) {
 	assert.True(t, strings.Contains(log, "bar:"))
 
 }
+func TestContainer_ResolveString(t *testing.T) {
+	log = ""
+	defer Reset()
+	Register(func() string { return "mock" })
+	Register(func(s string) Foobarer { return &Foobar{msg: s} })
+	Register(func() Fooer { return &Foo{} })
+	Register(func() Barer { return &Bar{} })
+	var fb Foobarer
+	err := Resolve(&fb)
+	assert.Nil(t, err)
+	fb.Say(123, "Hello World")
+	t.Log(log)
+	assert.True(t, strings.Contains(log, "mock"))
+}