如何使用macwire

Question

注入特质我有一个Scala的特质

trait UserRepository { 
    def findByEmail(email: String): User 
} 

我想注入到这个服务与MacWire

class AccountService(){ 
    val userRepo = wire[UserRepository] 
} 

，然后在测试或

类使用

class AccountServiceSpec { 
    val userRepo = new UserRepositoryImpl() 
    val accountSvc = new AccountService() //<--not manually injecting repo in service constructor 
} 

，但我在服务类获得一个编译错误

找不到一个公共的构造函数，也不是 accounts.repository.UserRepository

Answer 1

您可以尝试变换userRepo类参数同伴对象，它允许macwire自动为服务提供其值：

import com.softwaremill.macwire._ 

case class User(email: String) 

trait UserRepository { 
    def findByEmail(email: String): User 
} 

class AccountService(val userRepo: UserRepository) 

class UserRepositoryImpl extends UserRepository{ 
    def findByEmail(email: String): User = new User(email) 
} 

class AccountServiceSpec { 
    val userRepo = new UserRepositoryImpl() 
    val accountSvc = wire[AccountService] //<--not manually injecting repo in service constructor 
}