MATLAB Programming Fundamentals - MathWorks

Create Custom Boolean Constraint

This example shows how to create a custom boolean constraint that determines if a given

value is the same size as an expected value.

In a file in your working folder, create a file HasSameSizeAs.m. The constructor accepts

a value to compare to the actual size. This value is stored within the

ValueWithExpectedSize property. Because it is recommended that

BooleanConstraint implementations be immutable, set the property SetAccess

attribute to immutable.

classdef HasSameSizeAs < matlab.unittest.constraints.BooleanConstraint

properties(SetAccess=immutable)

ValueWithExpectedSize

end

methods

function constraint = HasSameSizeAs(value)

constraint.ValueWithExpectedSize = value;

end

end

end

Include these methods in the methods block in HasSameSizeAs.m. Since the

BooleanConstraint class is a subclass of Constraint, classes that derive from it must

implement the satisfiedBy and getDiagnosticFor methods. For more information

about these methods, see matlab.unittest.constraints.Constraint.

methods

function bool = satisfiedBy(constraint, actual)

bool = isequal(size(actual), size(constraint.ValueWithExpectedSize));

end

function diag = getDiagnosticFor(constraint, actual)

import matlab.unittest.diagnostics.StringDiagnostic

if constraint.satisfiedBy(actual)

diag = StringDiagnostic('HasSameSizeAs passed.');

else

diag = StringDiagnostic(sprintf(...

'HasSameSizeAs failed.\nActual Size: [%s]\nExpectedSize: [%s]',...

int2str(size(actual)),...

int2str(size(constraint.ValueWithExpectedSize))));

end

end

end

Include the getNegativeDiagnosticFor method in the methods block with protected

access in HasSameSizeAs.m. Classes that derive from BooleanConstraint must

implement the getNegativeDiagnosticFor method. This method must provide a

Diagnostic object that is expressed in the negative sense of the constraint.

Create Custom Boolean Constraint