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This project is not being actively maintained. Instead consider using Verify. See Migrating from ApprovalTests for more information.

Capturing Human Intelligence - ApprovalTests is an open source assertion/verification library to aid unit testing.

It is compatible with most .Net unit testing frameworks (Nunit, MsTest, xUnit, MBUnit)


What can it be used for?

Approval Tests can be used for verifying objects that require more than a simple assert. They also come prepackaged with utilities for some common .Net scenarios including:

Video Tutorials

You can watch a bunch of short videos on getting started and using ApprovalTests in .Net at YouTube


If you prefer auditory learning, you might enjoy the following podcast


Available on NuGet

Install-Package ApprovalTests


Verifying a List

public class SampleTest
    public void TestList()
        var names = new[] {"Llewellyn", "James", "Dan", "Jason", "Katrina"};
        Approvals.VerifyAll(names, label: "");

snippet source | anchor

Will Produce a File


[0] = Dan
[1] = James
[2] = Jason
[3] = Katrina
[4] = Llewellyn

snippet source | anchor

It will also open these 2 files (.received. & .approved. ) in a diff editor.

You can approve these results by copying everything (ctrl+a, ctrl+c) and pasting it in the right hand side (ctrl+a, ctrl+v)

In most situations, you will use one of the supported DiffTools to examine and approve the result.

Alternatively, you can rename the .received. file to SampleTest.TestList.approved.txt and the test will now pass.

note: The diff tools are NOT opened when the tests pass, only on failure.

Approved File Artifacts

The *.approved.* files must be checked into source your source control. ApprovalTests now ignores line endings by default (so you can remove *.approved.* binary from your .gitattributes file if you added previously).

If you would like to verify line endings, simply add [assembly: IgnoreLineEndingsAttribute(false)] to your AssemblyInfo.cs

Do not add *.received.* files to your source control (they are transitory, and some SCMs like TFS will lock them or mark them read-only, which will break every dependent test).

More Info


ask on twitter: @LlewellynFalco or #ApprovalTests



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