Controlling execution order of unit tests in Visual Studio

Question

Okay, I\'m done searching for good information on this. I have a series of Unit Tests that call a static class which, once initialized, sets properties that cannot (or I don

Answer 1

As you should know by now, purists say it's forbiden to run ordered tests. That might be true for unit tests. MSTest and other Unit Test frameworks are used to run pure unit test but also UI tests, full integration tests, you name it. Maybe we shouldn't call them Unit Test frameworks, or maybe we should and use them according to our needs. That's what most people do anyway.

I'm running VS2015 and I MUST run tests in a given order because I'm running UI tests (Selenium).

Priority - Doesn't do anything at all This attribute is not used by the test system. It is provided to the user for custom purposes.

orderedtest - it works but I don't recommend it because:

1. An orderedtest a text file that lists your tests in the order they should be executed. If you change a method name, you must fix the file.
2. The test execution order is respected inside a class. You can't order which class executes its tests first.
3. An orderedtest file is bound to a configuration, either Debug or Release
4. You can have several orderedtest files but a given method can not be repeated in different orderedtest files. So you can't have one orderedtest file for Debug and another for Release.

Other suggestions in this thread are interesting but you loose the ability to follow the test progress on Test Explorer.

You are left with the solution that purist will advise against, but in fact is the solution that works: sort by declaration order.

The MSTest executor uses an interop that manages to get the declaration order and this trick will work until Microsoft changes the test executor code.

This means the test method that is declared in the first place executes before the one that is declared in second place, etc.

To make your life easier, the declaration order should match the alphabetical order that is is shown in the Test Explorer.

• A010_FirstTest
• A020_SecondTest
• etc
• A100_TenthTest

I strongly suggest some old and tested rules:

• use a step of 10 because you will need to insert a test method later on
• avoid the need to renumber your tests by using a generous step between test numbers
• use 3 digits to number your tests if you are running more than 10 tests
• use 4 digits to number your tests if you are running more than 100 tests

VERY IMPORTANT

In order to execute the tests by the declaration order, you must use Run All in the Test Explorer.

Say you have 3 test classes (in my case tests for Chrome, Firefox and Edge). If you select a given class and right click Run Selected Tests it usually starts by executing the method declared in the last place.

Again, as I said before, declared order and listed order should match or else you'll in big trouble in no time.