System.Not Supported 用于模拟 ExecuteSQLCommand Moq Entity Framework Core 的异常

Question

I am trying to write a unit test for a method in my database layer. I am getting error at context.Setup for ExecuteSqlCommand :

System.NotSupportedException: 'Unsupported expression: ... => .... ExecuteSqlCommand((RawSqlString)It.IsAny<string>(), It.IsAny<object[]>()) Extension methods (here: RelationalDatabaseFacadeExtensions.ExecuteSqlCommand) may not be used in setup / verification expressions.

My method looks like this:

public void InsertIntoQueue()
{           
    context.Database
           .ExecuteSqlCommand(" EXEC SP_Name param1",
                              new SqlParameter("param1", param1.value));           
}

My unit test is something like this:

[Fact]
[Trait("TestCategory", "Unit")]
public async void Test1_Ok()
{
    var context = new Mock<Context>();
    {
        context.Setup(x => x.Database.ExecuteSqlCommand(It.IsAny<string>(), It.IsAny<object[]>())).Returns(1);
        var repo = GetDBRepository(context.Object);
        repo.InsertIntoQueue();                
    }
}

Is there a way to mock the ExecuteSQLCommand method directly?

Answer 1

It is not possible to mock it directly as it is an extension method.

It is possible to mock what that extension method invokes though and mock it indirectly. I had a similar case and ended up implementing EntityFrameworkCore.Testing as it's a pretty involved Moq set up.

var relationalCommandMock = new Mock<IRelationalCommand>();
relationalCommandMock
    .Setup(m => m.ExecuteNonQuery(It.IsAny<IRelationalConnection>(), It.IsAny<IReadOnlyDictionary<string, object>>()))
    .Returns((IRelationalConnection providedConnection, IReadOnlyDictionary<string, object> providedParameterValues) => executeSqlCommandResult);
relationalCommandMock
    .Setup(m => m.ExecuteNonQueryAsync(It.IsAny<IRelationalConnection>(), It.IsAny<IReadOnlyDictionary<string, object>>(), It.IsAny<CancellationToken>()))
    .Returns((IRelationalConnection providedConnection, IReadOnlyDictionary<string, object> providedParameterValues, CancellationToken providedCancellationToken) => Task.FromResult(executeSqlCommandResult));
var relationalCommand = relationalCommandMock.Object;

var rawSqlCommandMock = new Mock<RawSqlCommand>(MockBehavior.Strict, relationalCommand, new Dictionary<string, object>());
rawSqlCommandMock.Setup(m => m.RelationalCommand).Returns(relationalCommand);
rawSqlCommandMock.Setup(m => m.ParameterValues).Returns(new Dictionary<string, object>());
var rawSqlCommand = rawSqlCommandMock.Object;

var rawSqlCommandBuilderMock = new Mock<IRawSqlCommandBuilder>();

rawSqlCommandBuilderMock
    .Setup(m => m.Build(It.IsAny<string>(), It.IsAny<IEnumerable<object>>()))
    .Returns((string providedSql, IEnumerable<object> providedParameters) => rawSqlCommand);

var rawSqlCommandBuilder = rawSqlCommandBuilderMock.Object;

var serviceProviderMock = new Mock<IServiceProvider>();
serviceProviderMock.Setup(m => m.GetService(It.Is<Type>(t => t == typeof(IConcurrencyDetector)))).Returns((Type providedType) => Mock.Of<IConcurrencyDetector>());
serviceProviderMock.Setup(m => m.GetService(It.Is<Type>(t => t == typeof(IRawSqlCommandBuilder)))).Returns((Type providedType) => rawSqlCommandBuilder);
serviceProviderMock.Setup(m => m.GetService(It.Is<Type>(t => t == typeof(IRelationalConnection)))).Returns((Type providedType) => Mock.Of<IRelationalConnection>());
var serviceProvider = serviceProviderMock.Object;

var databaseFacadeMock = new Mock<DatabaseFacade>(MockBehavior.Strict, mockedDbContext);
databaseFacadeMock.As<IInfrastructure<IServiceProvider>>().Setup(m => m.Instance).Returns(serviceProvider);
var databaseFacade = databaseFacadeMock.Object;

Mock.Get(mockedDbContext).Setup(m => m.Database).Returns(databaseFacade);

This is the set up required to support both ExecuteSqlCommand and ExecuteSqlCommandAsync. executeSqlCommandResult is the integer result to return when invoked.

Note that I am passing the mocked db context to the database facade mock constructor then performing another Moq set up on the mocked database, I get away with this as I have already performed a set up on the DbContext Database property as part of mocking the db context. I have observed test success with an inline new instance so I don't think it matters, just in my case I didn't want to spin up another instance.