Create Basic Parameterized Test - MATLAB & Simulink (original) (raw)

This example shows how to create a parameterized test to test the output of a function in terms of value, class, and size.

Create Function to Test

In your current folder, create a function in the filesierpinski.m. This function returns a matrix representing an image of a Sierpinski carpet fractal. It takes as input the fractal level and an optional data type.

function carpet = sierpinski(levels,classname) if nargin == 1 classname = 'single'; end

msize = 3^levels; carpet = ones(msize,classname);

cutCarpet(1,1,msize,levels) % Begin recursion

function cutCarpet(x,y,s,cl)
    if cl
        ss = s/3; % Define subsize
        for lx = 0:2
            for ly = 0:2
                if lx == 1 && ly == 1
                    % Remove center square
                    carpet(x+ss:x+2*ss-1,y+ss:y+2*ss-1) = 0;
                else
                    % Recurse
                    cutCarpet(x+lx*ss,y+ly*ss,ss,cl-1)
                end
            end
        end
    end
end

end

Create TestCarpet Test Class

In a file in your current folder, create the TestCarpet class to test the sierpinski function. Define the properties used for parameterized testing in a properties block with theTestParameter attribute.

classdef TestCarpet < matlab.unittest.TestCase
properties (TestParameter) type = {'single','double','uint16'}; level = struct('small',2,'medium',4,'large',6); side = struct('small',9,'medium',81,'large',729); end end

The type property contains the different data types you want to test. The level property contains the different fractal levels you want to test. The side property contains the number of rows and columns in the Sierpinski carpet matrix and corresponds to the level property.

Define Test methods Block

In a methods block with the Test attribute, define three test methods:

The testRemainPixels method tests the output of the sierpinski function by verifying that the number of nonzero pixels is the same as expected for a particular level. This method uses the level property and, therefore, results in three test elements—one for each value in level.
The testClass method tests the class of the output from the sierpinski function with each combination of the type andlevel parameter values (that is, exhaustive parameter combination). The method results in nine test elements.
The testDefaultL1Output method does not use aTestParameter property and, therefore, is not parameterized. The method verifies that the level 1 matrix contains the expected values. Because the test method is not parameterized, it results in one test element.

methods (Test)
    function testRemainPixels(testCase,level)
        expPixelCount = 8^level;
        actPixels = find(sierpinski(level));
        testCase.verifyNumElements(actPixels,expPixelCount)
    end
    
    function testClass(testCase,type,level)
        testCase.verifyClass( ...
            sierpinski(level,type),type)
    end
    
    function testDefaultL1Output(testCase)
        exp = single([1 1 1; 1 0 1; 1 1 1]);
        testCase.verifyEqual(sierpinski(1),exp)
    end
end

end

Define Test methods Block with ParameterCombination Attribute

Define the testNumel method to ensure that the matrix returned by the sierpinski function has the correct number of elements. Set the ParameterCombination attribute for the method to 'sequential'. Because the level and side properties each specify three parameter values, thetestNumel method is invoked three times — one time for each of the 'small', 'medium', and'large' values.

methods (Test)
    function testRemainPixels(testCase,level)
        expPixelCount = 8^level;
        actPixels = find(sierpinski(level));
        testCase.verifyNumElements(actPixels,expPixelCount)
    end
    
    function testClass(testCase,type,level)
        testCase.verifyClass( ...
            sierpinski(level,type),type)
    end
    
    function testDefaultL1Output(testCase)
        exp = single([1 1 1; 1 0 1; 1 1 1]);
        testCase.verifyEqual(sierpinski(1),exp)
    end
end

methods (Test, ParameterCombination = 'sequential')
    function testNumel(testCase,level,side)
        import matlab.unittest.constraints.HasElementCount
        testCase.verifyThat(sierpinski(level), ...
            HasElementCount(side^2))
    end
end

end

Run All Tests

At the command prompt, create a suite from TestCarpet.m. The suite has 16 test elements. MATLAB® includes parameterization information in the names of the suite elements.

suite = matlab.unittest.TestSuite.fromFile('TestCarpet.m'); {suite.Name}'

ans =

16×1 cell array

{'TestCarpet/testNumel(level=small,side=small)'  }
{'TestCarpet/testNumel(level=medium,side=medium)'}
{'TestCarpet/testNumel(level=large,side=large)'  }
{'TestCarpet/testRemainPixels(level=small)'      }
{'TestCarpet/testRemainPixels(level=medium)'     }
{'TestCarpet/testRemainPixels(level=large)'      }
{'TestCarpet/testClass(type=single,level=small)' }
{'TestCarpet/testClass(type=single,level=medium)'}
{'TestCarpet/testClass(type=single,level=large)' }
{'TestCarpet/testClass(type=double,level=small)' }
{'TestCarpet/testClass(type=double,level=medium)'}
{'TestCarpet/testClass(type=double,level=large)' }
{'TestCarpet/testClass(type=uint16,level=small)' }
{'TestCarpet/testClass(type=uint16,level=medium)'}
{'TestCarpet/testClass(type=uint16,level=large)' }
{'TestCarpet/testDefaultL1Output'                }

Run the tests.

Running TestCarpet .......... ...... Done TestCarpet

ans =

1×16 TestResult array with properties:

Name
Passed
Failed
Incomplete
Duration
Details

Totals: 16 Passed, 0 Failed, 0 Incomplete. 2.459 seconds testing time.

Run Tests with level Property Named 'small'

Use the selectIf method ofTestSuite to select test elements that use a particular parameterization. Select all test elements that use the parameter name'small' in the level parameterization property list. The filtered suite has five elements.

s1 = suite.selectIf('ParameterName','small'); {s1.Name}'

ans =

5×1 cell array

{'TestCarpet/testNumel(level=small,side=small)' }
{'TestCarpet/testRemainPixels(level=small)'     }
{'TestCarpet/testClass(type=single,level=small)'}
{'TestCarpet/testClass(type=double,level=small)'}
{'TestCarpet/testClass(type=uint16,level=small)'}

Run the filtered test suite.

Running TestCarpet ..... Done TestCarpet

Alternatively, you can create the same test suite directly using thefromFile method of TestSuite.

import matlab.unittest.selectors.HasParameter s1 = matlab.unittest.TestSuite.fromFile('TestCarpet.m', ... HasParameter('Name','small'));

Create Basic Parameterized Test - MATLAB & Simulink (original) (raw)

Create Function to Test

Create TestCarpet Test Class

Define Test methods Block

Define Test methods Block with ParameterCombination Attribute

Run All Tests

Run Tests with level Property Named 'small'

See Also

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