我目前正在为一个应用程序编写各种单元测试。
现在，我确实有测试来检查代码是否正常工作。但我是否也应该模拟，例如：
我知道这不是一个编码问题，但我想对此有一些一般性的想法。
如果需要，我想到了以下方法：
SettingsUnavailableMock.Setup(x => x.PageRepository.All()).Throws(new Exception());
SettingsUnavailableMock.Setup(x => x.PageRepository.Get(It.IsAny<int>())).Throws(new Exception());
SettingsUnavailableMock.Setup(x => x.PageRepository.Get(It.IsAny<string>())).Throws(new Exception());
SettingsUnavailableMock.Setup(x => x.PageRepository.Refresh(It.IsAny<Page>())).Throws(new Exception());
SettingsUnavailableMock.Setup(x => x.PageRepository.Save()).Throws(new Exception());
当然，添加所有存储库。
然后在我的测试课中，我可以选择我想使用的Mock。
答案 0 :(得分：1)
这实际上取决于您的代码与数据库交互的内容。
单元测试背后的理念是单独测试一个类。应该模拟其所有外部依赖项。
但是，您也可以检查您的类是否正确使用了它的依赖项。这将是交互测试
最终，如果一切听起来不错，你想检查整个系统是否一起工作。这是集成测试。
请注意，有一些图书馆允许您更轻松地执行集成测试，例如Specflow
public class Product
{
public int Id { get; set; }
public string Name { get; set; }
}
public interface IProductRepository
{
List<Product> LoadProducts();
}
public class ProductRepository : IProductRepository
{
public List<Product> LoadProducts()
{
// database code which returns the list of product
return new List<Product>();
}
}
public class StorageStatisticsGenerator
{
private readonly IProductRepository _repository;
public StorageStatisticsGenerator(IProductRepository repository)
{
_repository = repository;
}
public int ComputeNumberOfProducts()
{
var products = _repository.LoadProducts();
return products.Count;
}
}
鉴于以下课程，您可能想要测试不同类型的东西。
[TestFixture]
public class StorageStatisticsGeneratorTests
{
private Mock<IProductRepository> _productRepository;
private StorageStatisticsGenerator _statisticGenerator;
[SetUp]
public void Setup()
{
_productRepository = new Mock<IProductRepository>();
_statisticGenerator = new StorageStatisticsGenerator(_productRepository.Object);
}
// In this test we test if the statistic generator works correctly
// This is a UNIT TEST
[Test]
public void ComputeNumberOfProducts_Should_Returns_TheCorrectCount()
{
// Arrange
_productRepository.Setup(p => p.LoadProducts()).Returns(new List<Product>
{
new Product(), new Product(), new Product()
});
// Act
int result = _statisticGenerator.ComputeNumberOfProducts();
// Assert
Assert.AreEqual(3, result);
}
// In this test we test if the statistic generator use the repository as expected
// This is an INTERACTION TEST, you could check corner case using "real life data"
[Test]
public void ComputeNumberOfProducts_Should_Use_The_Product_Repository()
{
// Arrange
_productRepository.Setup(p => p.LoadProducts()).Returns(new List<Product>
{
new Product()
});
// Act
_statisticGenerator.ComputeNumberOfProducts();
// Assert
_productRepository.Verify(p => p.LoadProducts());
}
// In this test we use the real repository this is an INTEGRATION TEST
// You can flag this kind of slow test to run only during the night for instabce
[Test, Category("Nightly")]
public void ComputeNumberOfProducts_Should_Correctly_Integrate_With_ProductRepository()
{
// Arrange
_statisticGenerator = new StorageStatisticsGenerator(new ProductRepository());
// Act
_statisticGenerator.ComputeNumberOfProducts();
// Assert
_productRepository.Verify(p => p.LoadProducts());
}
}
如果您想了解更多信息，请阅读The art of unit testing
答案 1 :(得分：1)
理想情况下，你应该测试以上所有内容;但是，这取决于你的情况。就个人而言，我总是测试一切我可以切实测试的东西。
花费很长时间的查询非常现实。 不可用的数据库也非常现实。
Query返回null我不太确定;但是，如果这是一个现实的情况，那么一定要将它存根并进行测试。
更新 - 基于评论，我认为添加
是一件好事public interface IRepository<T> where T : IRepositoryEntry, new()
{
event EventHandler<RepositoryOperationEventArgs> InsertEvent;
event EventHandler<RepositoryOperationEventArgs> UpdateEvent;
event EventHandler<RepositoryOperationEventArgs> DeleteEvent;
IList<String> PrimaryKeys { get; }
void Insert(T Entry);
void Update(T Entry);
void Delete(Predicate<T> predicate);
bool Exists(Predicate<T> predicate);
T Retrieve(Predicate<T> predicate);
IEnumerable<T> RetrieveAll();
}
public interface IRepositoryEntry
{
IList<String> GetPrimaryKeys();
}
public class OracleRepository
{
const string ConnectionString = "*"
public static IDbConnection GetIDbConnection()
{
IDbConnection connection = new OracleConnection(ConnectionString).OpenConnection();
return connection;
}
public IDbConnection GetConnection()
{
IDbConnection connection = new OracleConnection(ConnectionString).OpenConnection();
return connection;
}
}
public class OracleRepository<T> : OracleRepository, IDisposable, IRepository<T> where T : RepositoryEntryBase, IRepositoryEntry, new()
{
/// <summary>
/// Gets all property names from a type.
/// </summary>
/// <returns>IEnumerable of strings</returns>
static IEnumerable<String> GetEntryPropertyNames(Type type)
{
foreach (var propInfo in type.GetProperties())
yield return propInfo.Name;
}
public event EventHandler<RepositoryOperationEventArgs> InsertEvent;
public event EventHandler<RepositoryOperationEventArgs> UpdateEvent;
public event EventHandler<RepositoryOperationEventArgs> DeleteEvent;
#region Properties
public IList<String> PrimaryKeys
{
get
{
return primaryKeys.AsReadOnly();
}
private set
{
primaryKeys = new List<String>(value);
}
}
public IList<String> Properties { get; private set; }
public String InsertText { get; private set; }
public String UpdateText { get; private set; }
public String DeleteText { get; private set; }
public String SelectText { get; private set; }
#endregion
#region Fields
IDbConnection connection;
IDbTransaction transaction;
List<String> primaryKeys;
#endregion
#region Constructors
public OracleRepository()
{
PrimaryKeys = new List<String>(new T().GetPrimaryKeys());
Properties = new List<String>(GetEntryPropertyNames(typeof(T))).AsReadOnly();
InsertText = GenerateInsertText();
UpdateText = GenerateUpdateText();
SelectText = GenerateSelectText();
DeleteText = GenerateDeleteText();
connection = GetConnection();
}
#endregion
#region Interface Implementations
public void Insert(T Entry)
{
Insert(connection, Entry);
}
public void Update(T Entry)
{
Update(connection, Entry);
}
public void Delete(Predicate<T> predicate)
{
Delete(connection, predicate);
}
public T Retrieve(Predicate<T> predicate)
{
return Retrieve(connection, predicate);
}
public bool Exists( Predicate<T> predicate)
{
return Exists(connection, predicate);
}
public IEnumerable<T> RetrieveAll()
{
return RetrieveAll(connection);
}
public void Dispose()
{
if (transaction != null)
transaction.Dispose();
connection.Dispose();
}
#endregion
#region Public Methods
public void StartTransaction()
{
if (transaction != null)
throw new InvalidOperationException("Transaction is already set. Please Rollback or commit transaction");
transaction = connection.BeginTransaction();
}
public void CommitTransaction()
{
transaction.Commit();
transaction.Dispose();
transaction = null;
}
public void RollbackTransaction()
{
transaction.Rollback();
transaction.Dispose();
transaction = null;
}
public void Insert(IDbConnection connection, T Entry)
{
Type type = typeof(T);
List<Object> args = new List<Object>();
for (int i = 0; i < Properties.Count; i++)
args.Add(type.GetProperty(Properties[i]).GetValue(Entry));
connection.NonQuery(InsertText, args.ToArray());
if (InsertEvent != null)
InsertEvent(this, new OracleRepositoryOperationEventArgs() { Entry = Entry, Transaction = (transaction != null) });
}
public void Update(IDbConnection connection, T Entry)
{
Type type = typeof(T);
List<Object> args = new List<Object>();
foreach (var propertyName in Properties.Where(p => !PrimaryKeys.Any(k => k == p)))
args.Add(type.GetProperty(propertyName).GetValue(Entry));
foreach (var PropertyName in PrimaryKeys)
args.Add(type.GetProperty(PropertyName).GetValue(Entry));
connection.NonQuery(UpdateText, args.ToArray());
if (UpdateEvent != null)
UpdateEvent(this, new OracleRepositoryOperationEventArgs() { Entry = Entry, Transaction = (transaction != null) });
}
public void Delete(IDbConnection connection, Predicate<T> predicate)
{
var entryList = RetrieveAll(connection).Where(new Func<T, bool>(predicate));
Type type = typeof(T);
foreach(var entry in entryList)
{
List<Object> args = new List<Object>();
foreach (var PropertyName in PrimaryKeys)
args.Add(type.GetProperty(PropertyName).GetValue(entry));
connection.NonQuery(DeleteText, args.ToArray());
if (DeleteEvent != null)
DeleteEvent(this, new OracleRepositoryOperationEventArgs() { Entry = null, Transaction = (transaction != null) });
}
}
public T Retrieve(IDbConnection connection, Predicate<T> predicate)
{
return RetrieveAll(connection).FirstOrDefault(new Func<T, bool>(predicate));
}
public bool Exists(IDbConnection connection, Predicate<T> predicate)
{
return RetrieveAll(connection).Any(new Func<T, bool>(predicate));
}
public IEnumerable<T> RetrieveAll(IDbConnection connection)
{
List<T> collection = new List<T>();
var result = connection.Query(SelectText);
foreach (var row in result.Tuples)
collection.Add(RepositoryEntryBase.FromPlexQueryResultTuple(new T(), row) as T);
return collection;
}
#endregion
#region Private Methods
String GenerateInsertText()
{
String statement = "INSERT INTO {0}({1}) VALUES ({2})";
//Do first entry here becasse its unique input.
String columnNames = Properties.First();
String delimiter = ", ";
String bph = ":a";
String placeHolders = bph + 0;
//Start @ 1 since first entry is already done
for (int i = 1; i < Properties.Count; i++)
{
columnNames += delimiter + Properties[i];
placeHolders += delimiter + bph + i;
}
statement = String.Format(statement, typeof(T).Name, columnNames, placeHolders);
return statement;
}
String GenerateUpdateText()
{
String bph = ":a";
String cvpTemplate = "{0} = {1}";
String statement = "UPDATE {0} SET {1} WHERE {2}";
//Can only set Cols that are not a primary Keys, Get those Columns
var Settables = Properties.Where(p => !PrimaryKeys.Any(k => k == p)).ToList();
String cvp = String.Format(cvpTemplate, Settables.First() , bph + 0 );
String condition = String.Format(cvpTemplate, PrimaryKeys.First(), bph + Settables.Count);
//These are the values to be set | Start @ 1 since first entry is done above.
for (int i = 1; i < Settables.Count; i++)
cvp += ", " + String.Format(cvpTemplate, Settables[i], bph + i);
//This creates the conditions under which the values are set. | Start @ 1 since first entry is done above.
for (int i = Settables.Count + 1; i < Properties.Count; i++)
condition += ", " + String.Format(cvpTemplate, PrimaryKeys[i - Settables.Count], bph + i);
statement = String.Format(statement, typeof(T).Name, cvp, condition);
return statement;
}
String GenerateDeleteText()
{
String bph = ":a";
String cvpTemplate = "{0} = {1}";
String statement = "DELETE FROM {0} WHERE {1}";
String condition = String.Format(cvpTemplate, PrimaryKeys.First(), bph + 0);
for (int i =1; i < PrimaryKeys.Count; i++)
condition += ", " + String.Format(cvpTemplate, PrimaryKeys[i], bph + i);
statement = String.Format(statement, typeof(T).Name, condition);
return statement;
}
String GenerateSelectText()
{
String statement = "SELECT * FROM {0}";
statement = String.Format(statement, typeof(T).Name);
return statement;
}
#endregion
}
这是实现IReposistoryEntry的元素的样子：
public class APPS : RepositoryEntryBase, IRepositoryEntry
{
public int APP_ID { get; set; }
public string AUTH_KEY { get; set; }
public string TITLE { get; set; }
public string DESCRIPTION { get; set; }
public int IS_CLIENT_CUSTOM_APP { get; set; }
public APPS() : base() {
primaryKeys.Add("APP_ID");
}
public APPS(PlexQueryResultTuple plexTuple) : base(plexTuple) { }
}
public class RepositoryEntryBase
{
public static RepositoryEntryBase FromPlexQueryResultTuple( RepositoryEntryBase reb, PlexQueryResultTuple plexTuple)
{
if (plexTuple.parent == null)
throw new NotSupportedException("This Operation is Not supported by this PlexTuple.");
Type type = reb.GetType();
var pInfo = type.GetProperties();
PlexQueryResult result = plexTuple.parent;
foreach (var p in pInfo)
{
int index = result.Tuples.IndexOf(plexTuple);
if (result[p.Name, index] == null)
continue;
var conversationType = Nullable.GetUnderlyingType(p.PropertyType) ?? p.PropertyType;
object value = Convert.ChangeType(result[p.Name, index], (result[p.Name, index] != null)?conversationType: p.PropertyType);
p.SetValue(reb, value);
}
return reb;
}
protected IList<String> primaryKeys;
public RepositoryEntryBase()
{
primaryKeys = new List<String>();
}
public RepositoryEntryBase(PlexQueryResultTuple plexTuple) : this()
{
FromPlexQueryResultTuple(this, plexTuple);
}
public IList<String> GetPrimaryKeys()
{
return primaryKeys;
}
}
下面我发布了模拟数据库。这里重新认识的重要一点是，测试实际上使用了界面，我可以交换，可以很容易地将真实数据库与模拟数据库交换。我喜欢重复使用这个代码（它实际上在我的dll中）。所以我不必为每个项目重新编码数据库代码。
public class InMemoryRepository<T> : IRepository<T> where T : IRepositoryEntry, new()
{
//RepositoryEntryBase,
public event EventHandler<RepositoryOperationEventArgs> InsertEvent;
public event EventHandler<RepositoryOperationEventArgs> UpdateEvent;
public event EventHandler<RepositoryOperationEventArgs> DeleteEvent;
public IList<String> PrimaryKeys { get; protected set; }
List<T> data;
public InMemoryRepository() {
PrimaryKeys = new List<String>(new T().GetPrimaryKeys());
data = new List<T>();
}
public void Insert(T Entry){
if(Get(Entry) != null)
throw new Exception("Duplicate Entry - Identical Key already exists");
data.Add(Entry);
if (InsertEvent != null)
InsertEvent(this, new RepositoryOperationEventArgs() { Entry = Entry });
}
public void Update(T Entry){
var obj = Get(Entry);
if (obj == null)
throw new Exception("Object does not exist");
obj = Entry;
if (UpdateEvent != null)
UpdateEvent(this, new RepositoryOperationEventArgs() { Entry = obj });
}
public void Delete(Predicate<T> predicate)
{
data.RemoveAll(predicate);
if (DeleteEvent != null)
DeleteEvent(this, new RepositoryOperationEventArgs() { Entry = null });
}
public bool Exists(Predicate<T> predicate)
{
return data.Exists(predicate);
}
public T Retrieve(Predicate<T> predicate)
{
return data.FirstOrDefault(new Func<T, bool>(predicate));
}
public IEnumerable<T> RetrieveAll()
{
return data.ToArray();
}
T Get(T Entry)
{
//Returns Entry based on Identical PrimaryKeys
Type entryType = typeof(T);
var KeyPropertyInfo = entryType.GetProperties().Where(p => PrimaryKeys.Any(p2 => p2 == p.Name));
foreach (var v in data)
{
//Assume the objects are identical by default to prevent false positives.
Boolean AlreadyExists = true;
foreach (var property in KeyPropertyInfo)
if (!property.GetValue(v).Equals(property.GetValue(Entry)))
AlreadyExists = false;
if (AlreadyExists)
return v;
}
return default(T);
}
}