How can I set a unit test class variable from a test function?

I am trying to write a unit test class that includes a teardown function that writes a simple report. During execution of the different tests, I'd like to set some class variables that can then be accessed by the teardown function. I've created a simple example below to illustrate this. In this example, why is it that the test01 function can set testCase.variable, but the teardown function doesn't see it?

classdef testClass < matlab.unittest.TestCase
    properties
        variable = []
    end
    methods (TestClassTeardown)
        function teardown(testCase)
            fprintf('Variable was set to %i', testCase.variable);
        end
    end
    methods(Test)
        function test01(testCase)
            testCase.variable = 5;
            testCase.verifyEqual(testCase.variable, 5);
        end
    end
end

Answer 1

[Andy Campbell]

Hello mg,

In order to support the principle of Independent Tests, each test gets its own independent copy of the TestCase instance. The TestCase instance that is created and passed into TestClassSetup gets copied for every test method. This means that each test can have its own listeners and is more likely to remain independent. However, a shallow copy is made from the instance passed into TestClassSetup and TestClassTeardown methods in order for the test methods to use the data setup in TestClassSetup. But the Test methods are prevented from modifying the Class instance for every other Test method, or for the original TestCase modified in TestClassSetup and subsequently passed into TestClassTeardown.

However, what you are trying to do seems to be best solved by writing a plugin rather than doing this from the test content itself. See the following to get started:

• Plugin High Level Overview
• Example 1
• Example 2

Does that help get you started?