我无法为此代码编写测试..有人告诉我该怎么做吗？

Question

This is the code..

this class has list, method to add project into list

class ABC
 {
    private List<Project> List { get; set; } = new List<Project>(); // List for project

     public List<Project> List
    {
        get { return ProjectList; } 
    }   

   public void AddProject(Project p) // Method for project addition
     {
      if (!List.Any(x => x.Id == p.Id)) // to check project id already not exist
       {
        List.Add(p); // it will add if already not into list
       }            
     }
  }

I want to write n-unit test for "AddProject" method

I am stuck At 2)Act and 3)Assert

Answer 1

As Somebody mentioned, there is no way to check that the List was modified - you need some externally visible change to make a useful test.

I see some ideas:

1. Make the list public, with a private set - so you can observe it.
2. Create a getter for a Ireadonlycollection, so you can expose the list but disallow modifying the contents.
3. You could use Internal visibillity too and configurre your project accordingly.

Answer 2

Here is a full example:

i have added a new function called HasPrject you can use it in any place to check if the list has a specific project.

public class Program
{
 static void Main(string[] args)
 {
    ABC abc = new ABC();
    Project p = new Project("1");
    abc.AddProject(p);
    Console.WriteLine(abc.HasProject(p));    
    }
}

class ABC
{

private List<Project> List { get; set; } = new List<Project>();

public Boolean HasProject(Project p){
    return List.Any(x => x.Id == p.Id);
}

public Boolean HasProject(Project p){
    return List.Any(x => x.Id == p.Id);
}

 public void AddProject(Project p) // Method for project addition
 {
    if (!List.Any(x => x.Id == p.Id)) // to check project id already not exist
    {
        List.Add(p); // it will add if already not into list
     }            
  }
}

class Project
{
   public Project(string Id)
   {
      this.Id = Id;
   }
   public string Id;
}