Create Reusable Mock of FileInfo and other Core Classes

[Kevin]

I have determined that the following works:

public class TestCase1
{
    static TestCase1()
    {
        Mock.Replace<FileInfo, bool>(x => x.Exists).In<TestCase1>();
    }

    [Theory]
    [InlineData(false)]
    [InlineData(true)]
    public void MockedFileExists(bool expected)
    {
        FileInfo file = Helper.GetMockedFile(expected);

        bool actual = file.Exists;

        Assert.Equal(expected, actual);
    }
}

public class TestCase2
{
    static TestCase2()
    {
        Mock.Replace<FileInfo, bool>(x => x.Exists).In<TestCase2>();
    }

    [Theory]
    [InlineData(false)]
    [InlineData(true)]
    public void MockedFileExists(bool expected)
    {
        FileInfo file = Helper.GetMockedFile(expected);

        bool actual = file.Exists;

        Assert.Equal(expected, actual);
    }
}

public class Helper
{
    public static FileInfo GetMockedFile(bool exists)
    {
        FileInfo file = Mock.Create<FileInfo>("c:\\test.jpg");
        Mock.Arrange(() => file.Exists).Returns(exists);
        return file;
    }
}

I have two questions regarding the previous code:

1. Is there a way I can specify the Mock.Replace once and not have to specify it in every code file I use the helper method?
2. WIth this approach I have to add a Mock.Replace method for each method that I want to mock.  in cases where I am mocking multiple method calls is there a way to avoid having to specify a Mock.Replace for each method?

[Kaloyan]

Hello Kevin,

 Thank you for contacting Telerik support.

 As I can understand you would like to initialize the Mock.Replace<T> on assembly level. Unfortunately this is not supported in JustMock, because it is a performance blocker in most cases. In JustMock "Mock.Replace" is class based and as such you must initialize it on class level.

 I would recommend you grouping the test methods, that requires MSCorlib mocking into one class, if possible. This will save you a lot of execution time and also you won`t have to write the initialization for every test method you have.

 I hope this answers your question. If there is anything else I can help you with, do not hesitate to ask.

Kind regards,
Kaloyan
the Telerik team