Generate Tests with Suggested Values for Function Inputs

Create Tests

To create tests with suggested values, open a function file in the Editor and use the Generate Test > Suggest test inputs option from the MATLAB Toolstrip. The Suggested Test Inputs dialog box displays values based on the function argument validation of the current function. You can review the suggested values, customize your selection, and then create a test file.

For example, in the Editor, open the file for a function named rectangleArea, which computes the area of a rectangle given the lengths of its sides. To validate its inputs, the function uses an arguments block.

function area = rectangleArea(side1,side2)
arguments
    side1 (1,1) double {mustBePositive}
    side2 (1,1) double {mustBePositive}
end

area = side1 * side2;
end

To create tests with suggested input values for the rectangleArea function, on the Editor tab, in the Test section, select Generate Test > Suggest test inputs. The Suggested Test Inputs dialog box displays suggested values for the function inputs, including only values that the function can accept. Because the arguments block of the rectangleArea function restricts inputs to positive numeric scalars, the suggested values in this example are positive finite and infinite values.

The suggested values are based on function argument validation. To update the suggested values after modifying the source code, click Refresh Table in the dialog box. To display only the selected values, click Filter Table .

In the dialog box, you can accept the suggested values, exclude specific values by clearing their corresponding check boxes, or choose other scenarios to generate test data. In this example, create tests for the suggested values by clicking Generate Test. The testing framework generates a test class that contains one test per suggested input value. Each test calls the function with one suggested input while using default values for the remaining inputs.

% Autogenerated test file for rectangleArea using suggested inputs
classdef rectangleAreaTest < matlab.unittest.TestCase
    properties
        % Default input values

        side1Default = 62

        side2Default = 10
    end

    methods (Test)
        % Tests for input arguments with suggested values
        function testSide1IsPositiveInfinity(testCase)
            side1 = Inf;
            rectangleArea(side1, testCase.side2Default);
        end

        function testSide1IsPositiveNumber(testCase)
            side1 = 13;
            rectangleArea(side1, testCase.side2Default);
        end

        function testSide2IsPositiveInfinity(testCase)
            side2 = Inf;
            rectangleArea(testCase.side1Default, side2);
        end

        function testSide2IsPositiveNumber(testCase)
            side2 = 90;
            rectangleArea(testCase.side1Default, side2);
        end
    end
end

Run Tests

You can run the generated tests to verify that the function executes without unexpected errors. For more information about ways to run tests, see Run MATLAB Tests.

For example, run the generated rectangleAreaTest test class by using the runtests function. All tests pass, confirming that the rectangleArea function executes without unexpected errors for the suggested input values.

results = runtests("rectangleAreaTest");

Running rectangleAreaTest
....
Done rectangleAreaTest
__________

You can customize the generated test class by adding qualifications to the Test methods. For example, you can verify the output of the function by using the verifyEqual method. This table shows how to update the testSide1IsPositiveInfinity method to verify the expected output.

function testSide1IsPositiveInfinity(testCase)
    side1 = Inf;
    rectangleArea(side1, testCase.side2Default);
end

function testSide1IsPositiveInfinity(testCase)
    side1 = Inf;
    actual = rectangleArea(side1, testCase.side2Default);
    testCase.verifyEqual(actual, Inf)
end

After adding qualifications, run the tests again to verify that the function produces the expected output for the suggested input values.