Generate Tests for MATLAB Source Code

Since R2025a

You can use MATLAB® Test™ to generate tests that exercise your MATLAB source code. You can also generate tests that generate target code from a MATLAB function and test it for equivalence. This table summarizes the different methods.

TaskBenefitsCreate Tests FromSpecifying Input and Expected Output Values
Generate basic unit test for current file

  • Generate basic test that executes the currently open script, function, or class file. Complete the test by specifying input and expected output values.

  • Generate tests for all methods in a class file.

Currently open script, function, or class file in the MATLAB Editor

  • You must specify the expected output values.

  • If the function or methods use an arguments block for input argument validation, MATLAB Test attempts to generate input argument values. Otherwise, you must specify the function or method input values.

Generate unit test for the current file using MATLAB Copilot

  • Generate tests that execute functions, classes, and methods in the currently open file by using MATLAB Copilot.

  • You can run the tests without specifying input values or expected output values.

Currently open script, function, or class file in the MATLAB Editor

  • You do not need to specify input or output values.

Generate unit test from commands that you executed in the MATLAB Command Window

  • Generate test that executes functions or methods that you executed in the MATLAB Command Window. Complete the test by specifying expected output values.

  • Generated tests use input values defined in the Command History.

Commands in the Command History panel

  • You must specify the expected output values.

  • You can define the function or method input values when you execute the commands in the MATLAB Command Window. However, if the commands in the Command History panel do not specify the values, you must specify them in the test.

Generate basic equivalence test for the current file

  • Generate basic equivalence test for the currently open function file. Complete the test by specifying input values. The test includes code that builds and executes the target code from the function in the currently open file, and verifies that the execution of the target code matches the execution of the function.

  • You can generate equivalence tests that generate code for these targets:

    • C code

    • C++ code

    • Python® packages

    • Java® packages

    • .NET assemblies

    • Deployable archives

    • Deployable C++ shared libraries

Currently open function file in the MATLAB Editor

  • You do not need to specify the expected output values.

  • You must specify the function input values.

Generate Basic Unit Tests for Current File

You can generate basic unit tests for the current source code file. The generated unit tests execute the source code and test the output by using the verifyEqual method. Complete the tests by specifying the expected output of the source code in the test, and if necessary, by specifying the input values. For more information about building on the generated code, see Create Basic Tests for MATLAB Source Code.

Generate Tests

To generate a test, open a source code file in MATLAB. Then, in the Editor or Live Editor tab, in the Test section, click Generate Test > Generate Test by using static analysis, or click Generate Test. The generated test opens.

Note

Alternatively, you can generate the tests by right-clicking in the Editor and selecting Create Test (since R2024a).

For example, suppose that you have a function called quadraticSolver. The function takes as inputs the coefficients of a quadratic polynomial and returns the roots of that polynomial.

function r = quadraticSolver(a,b,c)
% quadraticSolver returns solutions to the
% quadratic equation a*x^2 + b*x + c = 0.

r = sort([(-b + sqrt(b^2 - 4*a*c)) / (2*a); ...
    (-b - sqrt(b^2 - 4*a*c)) / (2*a)]);
end

The generated test for this function calls the quadraticSolver function to produce an output and uses the verifyEqual qualification method to test the produced output.

% This is an autogenerated sample test for file quadraticSolver.m
classdef testquadraticSolver < matlab.unittest.TestCase

    methods (Test)

        function test_quadraticSolver(testCase)
            % Specify the input(s) of quadraticSolver
            a = 
            b = 
            c = 

            % Specify the expected output(s) of quadraticSolver
            expected_r = 

            % Exercise the function quadraticSolver
            actual_r = quadraticSolver(a, b, c);

            testCase.verifyEqual(actual_r, expected_r);
        end
    end
end

Complete Tests

To avoid invalid expressions in the test, specify the function or method input values and the expected output of the source code file.

Note

If the function or methods use an arguments block for input argument validation, MATLAB Test attempts to generate input argument values for a function or class method. For more information, see Create Basic Tests for MATLAB Source Code.

For example, you can complete the test_quadraticSolver test by specifying values for the inputs a, b, and c and by specifying values for the expected output, expected_r.

% This is an autogenerated sample test for file quadraticSolver.m
classdef testquadraticSolver < matlab.unittest.TestCase

    methods (Test)

        function test_quadraticSolver(testCase)
            % Specify the input(s) of quadraticSolver
            a = 2;
            b = 2;
            c = -4;

            % Specify the expected output(s) of quadraticSolver
            expected_r = sort(roots([a b c]));

            % Exercise the function quadraticSolver
            actual_r = quadraticSolver(a, b, c);

            testCase.verifyEqual(actual_r, expected_r);
        end
    end
end

Generate Unit Tests for Current File Using MATLAB Copilot

If you have a MATLAB Copilot license, you can generate unit tests for a source code file using MATLAB Copilot. The generated tests execute the source code and test the output by using qualification methods. For more information about qualification methods, see Table of Verifications, Assertions, and Other Qualifications. You do not need to specify input or output values to run the tests.

Tip

MATLAB Copilot attempts to generate test code that qualifies the source code. However, the generated tests might contain errors or incorrect code. Validate the generated tests before use, and ensure that the tests exercise the functional behavior that you want to test. You can use MATLAB Copilot to explain the generated tests by selecting the test code in the Editor and, on the Editor tab, selecting Copilot > Explain Code.

To generate a test, open a source code file in MATLAB. Then, on the Editor or Live Editor tab, in the Test section, select Generate Test > Generate test for the current file using Copilot. The test file that opens can contain one or more tests. You do not need to specify input or expected output values in the test.

For example, suppose that you have a function named quadraticSolver.

function r = quadraticSolver(a,b,c)
% quadraticSolver returns solutions to the
% quadratic equation a*x^2 + b*x + c = 0.

arguments
    a (1,1) {mustBeNumeric,mustBeNonzero}
    b (1,1) {mustBeNumeric}
    c (1,1) {mustBeNumeric}
end

r = sort([(-b + sqrt(b^2 - 4*a*c)) / (2*a); ...
    (-b - sqrt(b^2 - 4*a*c)) / (2*a)]);
end

Then, generate tests for the function using MATLAB Copilot. Save the test file.

% This test file was generated by Copilot. Validate the generated output before use.
classdef TestQuadraticSolver < matlab.unittest.TestCase

    methods(Test)

        function testRealRoots(testCase)
            % Test case with real roots
            a = 1; b = -3; c = 2; % (x-1)(x-2) = 0
            expected = [1; 2];
            actual = quadraticSolver(a,b,c);
            testCase.verifyEqual(actual,expected,"AbsTol",1e-10);
        end

        function testComplexRoots(testCase)
            % Test case with complex roots
            a = 1; b = 2; c = 5; % x^2 + 2x + 5 = 0
            expected = [-1 + 2i; -1 - 2i];
            actual = quadraticSolver(a,b,c);
            testCase.verifyEqual(actual,expected,"AbsTol",1e-10);
        end

        function testDoubleRoot(testCase)
            % Test case with a double root
            a = 1; b = 2; c = 1; % (x+1)^2 = 0
            expected = [-1; -1];
            actual = quadraticSolver(a,b,c);
            testCase.verifyEqual(actual,expected,"AbsTol",1e-10);
        end

        function testInvalidInput(testCase)
            % Test case for invalid input (non-numeric)
            testCase.verifyError(@() quadraticSolver("a",2,1), ...
                "MATLAB:validators:mustBeNumeric");
        end

        function testZeroCoefficientA(testCase)
            % Test case for zero coefficient a
            testCase.verifyError(@() quadraticSolver(0,2,1), ...
                "MATLAB:validators:mustBeNonzero");
        end

    end
end

To validate the generated tests and test the source code, run the tests and review the results.

For example, when you run the tests in the TestQuadraticSolver file, the testComplexRoots test fails. The test values in the failure diagnostic indicate that the expected values do not match the order of the actual values. To fix this test failure, replace expected = [-1 + 2i; -1 - 2i]; with expected = sort([-1 + 2i; -1 - 2i]);. Save the test file and run the tests again. The tests pass.

Generate Unit Tests from Command History

You can generate unit tests from commands that you executed in the MATLAB Command Window. The generated tests execute the commands that you generate the tests from and test the output by using the verifyEqual method. Complete the tests by specifying the expected output of the source code.

Generate Tests

To generate a test from commands that you executed in the MATLAB Command Window, use the Command History panel. Right-click a command and select Generate Test. If the Command History icon is not in the sidebar, click the Open more panels button and select Command History.

To generate tests from commands that use ellipses to span multiple lines, select each of the lines, then generate the test.

To generate tests from conditional statements, select the first line of the conditional statement through the last line. For example, for code that includes if, elseif, else statements, select the entire if...end block. Alternatively, you can select the statements that execute if the if, elseif, or else statements are true.

When you generate tests from functions or methods that require input arguments, the tests use inputs that appear in the command history. For example, suppose that you have a function called quadraticSolver.

function r = quadraticSolver(a,b,c)
% quadraticSolver returns solutions to the
% quadratic equation a*x^2 + b*x + c = 0.

r = sort([(-b + sqrt(b^2 - 4*a*c)) / (2*a); ...
    (-b - sqrt(b^2 - 4*a*c)) / (2*a)]);
end

Suppose that you executed these commands.

>> a = 2;
>> b = 2;
>> c = -4;
>> r = quadraticSolver(a,b,c);

Generating a test from the execution of the quadraticSolver function creates this test.

% This is an autogenerated sample test for file quadraticSolver.m
classdef testquadraticSolver < matlab.unittest.TestCase
    methods (Test)
        function test_quadraticSolver(testCase)
            % Specify the input(s) of quadraticSolver
            a = 2;
            b = 2;
            c = -4;

            % Exercise the function quadraticSolver.m
            actualOutput_r = quadraticSolver(a,b,c);

            % Specify the expected output(s) of quadraticSolver
            expectedOutput_r = 

            testCase.verifyEqual(actualOutput_r, expectedOutput_r);
        end
    end
end

Complete Tests

To avoid invalid expressions in the test, specify the expected output of the source code.

For example, you can complete the test_quadraticSolver test by specifying values for the expected output, expected_r.

% This is an autogenerated sample test for file quadraticSolver.m
classdef testquadraticSolver < matlab.unittest.TestCase

    methods (Test)

        function test_quadraticSolver(testCase)
            % Specify the input(s) of quadraticSolver
            a = 2;
            b = 2;
            c = -4;

            % Specify the expected output(s) of quadraticSolver
            expected_r = sort(roots([a b c]));

            % Exercise the function quadraticSolver
            actual_r = quadraticSolver(a, b, c);

            testCase.verifyEqual(actual_r, expected_r);
        end
    end
end

Note

If the command history does not contain the commands that specify the input argument values, you must specify them in the test. This might occur if you specify input variables at the MATLAB Command Window by loading MAT files or by running scripts, specifying variable values by passing handle objects as function inputs, or if you delete commands that specify input variables from the command history.

Generate Equivalence Tests for Current Function File

You can generate equivalence tests for the current function file by using static analysis. The generated tests build target code for the current function, execute the target code, and verify that the execution of the target code matches the execution of the MATLAB function. Complete the tests by specifying the function input values. For more information about equivalence tests, see Generate C/C++ Code and Test for Equivalence and Generate Deployed Code Artifacts and Test for Equivalence.

You can generate equivalence tests that generate code for these targets:

  • C code

  • C++ code

  • Python packages

  • Java packages

  • .NET assemblies

  • Deployable archives

  • Deployable C++ shared libraries

Generate Tests

To generate an equivalence test, open a function file in MATLAB. Then, in the Editor or Live Editor tab, in the Test section, click Generate Test and, under Equivalence Tests, select your desired target language.

Tip

Selecting Generate Test > C/C++ Code Generation creates a C equivalence test. To specify the target language as C++, set the value of the CodeGenerationArguments argument of the build method to {"-lang:c++"}. For more information, see Specify Target Language as C++.

For example, suppose that you have a function called quadraticSolver.

function r = quadraticSolver(a,b,c)
% quadraticSolver returns solutions to the
% quadratic equation a*x^2 + b*x + c = 0.

r = sort([(-b + sqrt(b^2 - 4*a*c)) / (2*a); ...
    (-b - sqrt(b^2 - 4*a*c)) / (2*a)]);
end

Generating an equivalence test for this function by selecting Generate Test > Python Package creates this test, which:

  • Generates a Python package from the quadraticSolver function

  • Executes the Python package

  • Verifies that the execution of the Python package matches the execution of the quadraticSolver function by using the verifyExecutionMatchesMATLAB method

% This is an autogenerated sample test for file quadraticSolver.m
classdef testquadraticSolverCompilerEquivalence < matlabtest.compiler.TestCase
    methods (Test)
        function test_quadraticSolverCompilerEquivalence(testCase)
            functionToBuild = "quadraticSolver";
            compilerTarget = "pythonPackage";

            % Specify the inputs
            a = 
            b = 
            c = 
            inputArgs = {a, b, c};

            % Build artifact
            functionPath = which(functionToBuild);
            buildResults = testCase.build(functionPath, compilerTarget);

            % Execute artifact
            executionResults = testCase.execute(buildResults, inputArgs);

            % Execute MATLAB code and compare
            testCase.verifyExecutionMatchesMATLAB(executionResults)
        end
    end
end

Complete Tests

To avoid invalid expressions in the test, specify the function input values.

For example, you can complete the test_quadraticSolverCompilerEquivalence test by specifying values for the function input values a, b, and c.

% This is an autogenerated sample test for file quadraticSolver.m
classdef testquadraticSolverCompilerEquivalence < matlabtest.compiler.TestCase
    methods (Test)
        function test_quadraticSolverCompilerEquivalence(testCase)
            functionToBuild = "quadraticSolver";
            compilerTarget = "pythonPackage";

            % Specify the inputs
            a = 2;
            b = 2;
            c = -4;
            inputArgs = {a, b, c};

            % Build artifact
            functionPath = which(functionToBuild);
            buildResults = testCase.build(functionPath, compilerTarget);

            % Execute artifact
            executionResults = testCase.execute(buildResults, inputArgs);

            % Execute MATLAB code and compare
            testCase.verifyExecutionMatchesMATLAB(executionResults)
        end
    end
end
You can also customize the test by generating target code with additional options or by adding tolerances. For more information, see Generate C/C++ Code and Test for Equivalence and Generate Deployed Code Artifacts and Test for Equivalence.

Run Tests and Verify Results

You can run the generated tests by using any of these options:

For more information, see Run MATLAB Tests.

See Also

Apps

Functions

Topics