问题描述
我正在尝试将 EF6 的新模拟应用到我现有的代码中.
I am trying to apply the new mocking of EF6 to my existing code.
我有一个扩展 DbSet 的类.其中一种方法调用基类 (BdSet) 的 Create 方法.这是一个示例代码(不是完整的解决方案或真实姓名):
I have a class that Extends DbSet. One of the methods call the base class (BdSet) Create method. Here is the a sample code (not the complete solution or real names):
public class DerivedDbSet<TEntity> : DbSet<TEntity>, IKeyValueDbSet<TEntity>, IOrderedQueryable<TEntity> where TEntity : class
{
public virtual bool Add(string value1, string value2) {
var entity = Create(); // There is no direct implementation of the Create method it is calling the base method
// Do something with the values
this.Add(entity);
return true;
}
}
我正在使用 Test Doubles 示例进行模拟(这里是代码的平静):
I am mocking using the Test Doubles sample (here is the peace of code):
var data = new List<DummyEntity> {
new DummyEntity { Value1 = "First", Value2 = "001" },
new DummyEntity { Value1 = "Second", Value2 = "002" }
}.AsQueryable();
var mock = new Mock<DerivedDbSet<DummyEntity>>();
mock.CallBase = true;
mock.As<IQueryable<T>>().Setup(m => m.Provider).Returns(source.Provider);
mock.As<IQueryable<T>>().Setup(m => m.Expression).Returns(source.Expression);
mock.As<IQueryable<T>>().Setup(m => m.ElementType).Returns(source.ElementType);
mock.As<IQueryable<T>>().Setup(m => m.GetEnumerator()).Returns(source.GetEnumerator());
我已将 CallBase 属性设置为 true 以尝试强制调用基类...
I've set the CallBase property to true to try to force the call to the base class...
但我不断收到以下错误:
But I keep receiving the following error:
System.NotImplementedException:成员Create"尚未在继承自DbSet1"的类型DerivedDbSet1Proxy"上实现.'DbSet`1' 的测试替身必须提供所使用的方法和属性的实现.
System.NotImplementedException: The member 'Create' has not been implemented on type 'DerivedDbSet
1Proxy' which inherits from 'DbSet1'. Test doubles for 'DbSet`1' must provide implementations of methods and properties that are used.
我希望 create 调用回退到 DbSet 中的默认实现.
I want the call of create to fallback to the default implementation in DbSet.
有人可以帮我吗?
推荐答案
在对模拟 DbSet 的内部函数和异步引用进行了一些斗争之后，我提出了一个帮助类，它解决了我的大部分问题，并且可以作为有人执行.代码如下:
After some struggle with the internal functions and async references of mocking a DbSet I came out with a helper class that solved most of my problems and might serve as base to someone implementation. Here is the code:
public static class MockHelper
{
internal class TestDbAsyncQueryProvider<TEntity> : IDbAsyncQueryProvider {
private readonly IQueryProvider _inner;
internal TestDbAsyncQueryProvider(IQueryProvider inner) { _inner = inner; }
public IQueryable CreateQuery(Expression expression) { return new TestDbAsyncEnumerable<TEntity>(expression); }
public IQueryable<TElement> CreateQuery<TElement>(Expression expression) { return new TestDbAsyncEnumerable<TElement>(expression); }
public object Execute(Expression expression) { return _inner.Execute(expression); }
public TResult Execute<TResult>(Expression expression) { return _inner.Execute<TResult>(expression); }
public Task<object> ExecuteAsync(Expression expression, CancellationToken cancellationToken) { return Task.FromResult(Execute(expression)); }
public Task<TResult> ExecuteAsync<TResult>(Expression expression, CancellationToken cancellationToken) { return Task.FromResult(Execute<TResult>(expression)); }
}
internal class TestDbAsyncEnumerable<T> : EnumerableQuery<T>, IDbAsyncEnumerable<T> {
public TestDbAsyncEnumerable(IEnumerable<T> enumerable) : base(enumerable) { }
public TestDbAsyncEnumerable(Expression expression) : base(expression) { }
public IDbAsyncEnumerator<T> GetAsyncEnumerator() { return new TestDbAsyncEnumerator<T>(this.AsEnumerable().GetEnumerator()); }
IDbAsyncEnumerator IDbAsyncEnumerable.GetAsyncEnumerator() { return GetAsyncEnumerator(); }
public IQueryProvider Provider { get { return new TestDbAsyncQueryProvider<T>(this); } }
}
internal class TestDbAsyncEnumerator<T> : IDbAsyncEnumerator<T> {
private readonly IEnumerator<T> _inner;
public TestDbAsyncEnumerator(IEnumerator<T> inner) { _inner = inner; }
public void Dispose() { _inner.Dispose(); }
public Task<bool> MoveNextAsync(CancellationToken cancellationToken) { return Task.FromResult(_inner.MoveNext()); }
public T Current { get { return _inner.Current; } }
object IDbAsyncEnumerator.Current { get { return Current; } }
}
public static Mock<TDbSet> CreateDbSet<TDbSet, TEntity>(IList<TEntity> data, Func<object[], TEntity> find = null)
where TDbSet : class, IDbSet<TEntity>
where TEntity : class, new() {
var source = data.AsQueryable();
var mock = new Mock<TDbSet> { CallBase = true };
mock.As<IQueryable<TEntity>>().Setup(m => m.Expression).Returns(source.Expression);
mock.As<IQueryable<TEntity>>().Setup(m => m.ElementType).Returns(source.ElementType);
mock.As<IQueryable<TEntity>>().Setup(m => m.GetEnumerator()).Returns(source.GetEnumerator());
mock.As<IQueryable<TEntity>>().Setup(m => m.Provider).Returns(new TestDbAsyncQueryProvider<TEntity>(source.Provider));
mock.As<IDbAsyncEnumerable<TEntity>>().Setup(m => m.GetAsyncEnumerator()).Returns(new TestDbAsyncEnumerator<TEntity>(data.GetEnumerator()));
mock.As<IDbSet<TEntity>>().Setup(m => m.Create()).Returns(new TEntity());
mock.As<IDbSet<TEntity>>().Setup(m => m.Add(It.IsAny<TEntity>())).Returns<TEntity>(i => { data.Add(i); return i; });
mock.As<IDbSet<TEntity>>().Setup(m => m.Remove(It.IsAny<TEntity>())).Returns<TEntity>(i => { data.Remove(i); return i; });
if (find != null) mock.As<IDbSet<TEntity>>().Setup(m => m.Find(It.IsAny<object[]>())).Returns(find);
return mock;
}
public static Mock<DbSet<TEntity>> CreateDbSet<TEntity>(IList<TEntity> data, Func<object[], TEntity> find = null)
where TEntity : class, new() {
return CreateDbSet<DbSet<TEntity>, TEntity>(data, find);
}
}
这是一个使用示例(基于我之前给出的名称):
And here is a use sample (based on the names I've given before):
var data = new List<DummyEntity> {
new DummyEntity { Value1 = "First", Value2 = "001" } },
new DummyEntity { Value1 = "Second", Value2 = "002" } }
};
var mockDummyEntities = MockHelper.CreateDbSet<DerivedDbSet<DummyEntities>, DummyEntities>(data, i => data.FirstOrDefault(k => k.Value2 == (string)i[0]));
var mockContext = new Mock<DummyDbContext>();
mockContext.Setup(c => c.DummyEntities).Returns(mockDummyEntities.Object);
非常欢迎任何有关如何改进此解决方案的建议.
Any suggestions on how to improve this solution is very welcome.
问候
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