Check the equality of custom Classes using Matlab Unit Test suite

I am currently developing a class based Matlab Unit Test project, I am using the following code to verify the equality of two structures

verifyThat(testCase,struct1,IsEqualTo(struct2,'Within', RelativeTolerance(2*eps)))

But unfortunately I get an error message

    IsEqualTo failed.
    --> Path to failure: <Value>.req_results
        --> ObjectComparator failed.
            --> The objects are not equal using "isequal".
            --> The tolerance was ignored. The tolerance as specified does not support comparisons of Result values.

How to implement a method for testing the equality of two structures, consisting of elements belonging to different classes? Even when some of of them are custom classes.

I want a method compatible with verifyThat

[Stephen Carter]

I see that ObjectComparator is the one that is failing here.

You might be able to leverage the PublicPropertyComparator.supportingAllValues() static method here and use in place of object comparator.

Here is a workaround:

import matlab.unittest.constraints.IsEqualTo;
import matlab.unittest.constraints.PublicPropertyComparator;

% get access to the comparators that IsEqualTo uses by default:
tmp=IsEqualTo([]);
comparators = tmp.Comparator;

% add PublicPropertyComparator to the front (to be picked up before ObjectComparator does)
comparators = [PublicPropertyComparator.supportingAllValues(), comparators];

% perform qualification
verifyThat(testCase,struct1,IsEqualTo(struct2,...
  'Using',comparators,'Within', RelativeTolerance(2*eps)))

Note that PublicPropertyComparator will behave much differently than ObjectComparator in that it only supports MATLAB objects and only inspects the public properties.

Let me know if that helps.

[Jeno Boka]

Thank your for the fast, and exceptionally clear answer! That answer was really helpful! Thanks!

Answer 1

[Stephen Carter]

See answer in comment above.