NotificationService: Missing IEquatable<T> Implementation in NotificationMessage

[quicksln]

Describe the bug
The Notification Service relies on distributing messages from an observable collection:

ObservableCollection<NotificationMessage> Messages

The Notification Service includes two 'Notify' methods that check whether the collection contains a specific instance of NotificationMessage and add messages to the collection.

However, it does not function correctly because NotificationMessage does not implement IEquatable.
This interface implementation is necessary to determine if specific object instances are equal when using the List.Contains method.

To Reproduce
Steps to reproduce the behavior:

Run unit test :

        [Fact]
        public void NotificationService_MessagesCount_AfterAddingMessages()
        {
            NotificationService notificationService = new NotificationService();

            //Messages are the same so only one should be added
            notificationService.Notify(NotificationSeverity.Info, "Info Summary", "Info Detail", 4000);
            notificationService.Notify(new NotificationMessage()
            {
                Severity = NotificationSeverity.Info,
                Summary = "Info Summary",
                Detail = "Info Detail",
                Duration = 4000
            });

            int expectedMessagesNumber = 1;

            Assert.Equal(expectedMessagesNumber, notificationService.Messages.Count);
        }

Screenshots

Desktop (please complete the following information):
• OS: all
• Browser: [edge, chrome, safari
• Version: 4.22.1

Additional context
If my assumption is correct, I’ll be happy to fix it.

[enchev]

Hi @quicksln ,

Yes, sure! We accept pull requests!

[quicksln]

Pull request has been created. Please verify if everything is according to your development standards.
If I missed something, just let me know 😊