使用Moq在C#中对特定的MongoDb FilterDefintion进行单元测试

using Moq;
using MongoDB.Driver;

public interface IMongoDbRepository
{
    IMongoCollection<T> GetCollection<T>(string collectionName);
}

public class MongoDbRepository : IMongoDbRepository
{
    private readonly IMongoDatabase _database;

    public MongoDbRepository(string connectionString, string databaseName)
    {
        var client = new MongoClient(connectionString);
        _database = client.GetDatabase(databaseName);
    }

    public IMongoCollection<T> GetCollection<T>(string collectionName)
    {
        return _database.GetCollection<T>(collectionName);
    }
}

[Test]
public void TestFilterDefinition()
{
    // 创建Mock的IMongoCollection<T>对象
    var mockCollection = new Mock<IMongoCollection<MyDocument>>();

    // 创建要测试的FilterDefinition
    var filterDefinition = Builders<MyDocument>.Filter.Eq(x => x.Name, "John");

    // 设置Mock的Find方法返回期望的结果
    mockCollection.Setup(x => x.Find(It.IsAny<FilterDefinition<MyDocument>>(), null))
                  .Returns(new List<MyDocument>());

    // 创建要测试的类，并将Mock的IMongoCollection<T>对象传入构造函数
    var repository = new MyRepository(mockCollection.Object);

    // 调用要测试的方法
    var result = repository.GetDocuments(filterDefinition);

    // 断言结果是否符合预期
    Assert.IsEmpty(result);
}