Mock with interface style

[zhangzitao]

Describe the feature

Interface style

Motivation

Why this project doesn't write in interface style ?

Related Issues

It's impossible to mock xxxDo struct when importing dao in other packages, the only way to write unit test for these packages is to launch a sqlite database then fill some fake records.
Is there any way to mock method of xxxDo struct?
if not, I think it's not appropriate for serious project, only suitable for project that is not in need for unit test.

[zhangzitao]

take a look on this:

https://github.com/gogf/gf

[tr1v3r]

maybe u should try sqlmock? https://www.google.com.hk/search?q=gorm+sqlmock&oq=gorm+sqlmock&aqs=chrome..69i57j0i512l4j69i60l3.2218j0j7&sourceid=chrome&ie=UTF-8

[zhangzitao]

Sqlmock is a kind of integrated test, not unit test. And it's hard to compose test case.
When you have a situation of teamwork, for example, that some guy finished the orm package and it's unit tests, and you need to write service package which import orm package. It's not necessary to test orm again.

By the way, interface style will not change the api, but provide a way to mock. It's not complicated to implement.

[tr1v3r]

i don't understand, do you mean you want to mock with interface in orm's unit test?

[zhangzitao]

i don't understand, do you mean you want to mock with interface in orm's unit test?

Not in in orm's unit test. But in other packages which import orm and need to mock orm.

I've pushed a pr, you may understand what I mean after gen some code.

[tr1v3r]

i know about the interface style you said, just confused about its applicable scenes

[zhangzitao]

folder tree

• service
  • service.go
• orm
  • mock
    • mock.orm.go
  • user.gen.go
  • gen.go
• model
  • user.gen.go

service.go

package service

import (
    myproject/orm
    myproject/model
)

type service struct {
    QueryCtx orm.QueryCtx
}

func (s service) CreateUserIfCapacious() error {
     users, err := s.Query.User.Find()
     if len(users)>100 {
        return nil
     }
     return s.Query.User.Create(&model.User{ID:123, Name:"123"})
}

service_test.go

package service

import (
	mock_orm "myproject/orm/mock"
	orm "myproject/orm"
)
...

serviceInstance := new(service)
serviceInstance.QueryCtx = orm.QueryCtx{}
serviceInstance.QueryCtx.User = mock_orm.NewMockIUserDo(mockCtrl) // This is the point

Describe("Service", func() {
    Context("CreateUserIfCapacious", func() {
	    It("should be ok", func() {
	   	   mockOrmUser.EXPECT().Find().Return([]model.User{}, nil)
	   	   mockOrmUser.EXPECT().Create(gomock.Any()).Return(nil)
	   	   Expect(serviceInstance.CreateUserIfCapacious()).Error().To(BeNil())
	    })
    })
})
...

In this way, you can write unit test, not integrated. Focus on the logic of service. And you can find which part has problem if test fail after some features added.

[tr1v3r]

ok, i will carefully consider your proposal

[tr1v3r]

I will implement this feature in the near future.

[sol-mocha]

Hey folks, @RiverChu any updates on this issue?

[FLAGLORD]

Now gen only generates interface for DO object. Is it possible to generate interface for Query in gen.go? Most services would import Query instead of some DO object(because DO object would use context to initialilze). It would be easier to mock if we have a interface for Query and queryCtx