matlab.unittest.plugins.DiagnosticsValidationPlugin Class

In a file named ExampleTest.m in your current folder, create the ExampleTest class. Even though all the tests in the test class pass, the testThree method includes an intentional error in the supplied diagnostic.

classdef ExampleTest < matlab.unittest.TestCase
    methods (Test)
        function testOne(~)
            % Test code
        end

        function testTwo(~)
            % Test code
        end
        
        function testThree(testCase)
            % This test should use @dir as a function handle,
            % but there is a typo
            testCase.verifyEqual("myFile","myFile",@dri)
        end
    end
end

Import the DiagnosticsValidationPlugin class.

import matlab.unittest.plugins.DiagnosticsValidationPlugin

Create a test suite from the ExampleTest class.

suite = testsuite("ExampleTest");

Create a default test runner and use it to run the tests. The testing framework does not encounter the bug in the diagnostic code of testThree because the test passes.

runner = testrunner;
results1 = runner.run(suite);

Running ExampleTest
...
Done ExampleTest
__________

Now, add a DiagnosticsValidationPlugin instance to the test runner and run the tests. The framework executes the diagnostic code specified by the function handle, even though testThree passes, and encounters the bug.

runner.addPlugin(DiagnosticsValidationPlugin)
results2 = runner.run(suite);

Running ExampleTest
..
------------------------------
Validation of Test Diagnostic:
------------------------------
Error occurred while capturing diagnostics:
    Error using evalc
    Unrecognized function or variable 'dri'.
    
    Error in ExampleTest/testThree (line 14)
                testCase.verifyEqual("myFile","myFile",@dri)
.
Done ExampleTest
__________