我使用LINQ来创建对象和DI。
假设我有一个使用存储库的服务:
public FooService : Service, IFooService
{
private IFooRepository Repository { get; set; }
public GetSpecialFoos()
{
return from f in Repository.SelectAll()
where f.IsSpecial
select f;
}
public FooService(IFooRepository repository)
{
this.Repository = repository;
}
}
现在我可以使用构造函数注入来注入模拟存储库进行测试。通常,您会为此使用DI框架。但重要的是,模拟存储库可以使用LINQ访问对象:
public MockFooRepository : IFooRepository
{
public IList<Foo> Data { get; set; }
public IQueryable<Foo> SelectAll()
{
return Data.AsQueryable();
}
}
现在我可以测试:
[TestMethod]
public void GetSpecialFoos_returns_only_special_foos()
{
var specialId = 1;
var notSoSpecialId = 2;
var foos = new List<Foo>
{
new Foo
{
Id = specialId,
IsSpecial = true
},
new Foo
{
Id = notSoSpecialId,
IsSpecial = false
}
}
// use a DI framework here instead, in the real world
var repository = new MockFooRepository
{
Data = foos
};
var service = new FooService(repository);
var actual = service.GetSpecialFoos();
var returned = actual.First();
Assert.AreEqual(true, returned.IsSpecial);
Assert.AreEqual(specialId, returned.Id);
}