NUnit2045

Use Assert.EnterMultipleScope or Assert.Multiple

Description

Hosting Asserts inside an Assert.EnterMultipleScope or Assert.Multiple allows detecting more than one failure.

Motivation

When independent Assert statements are called from an Assert.EnterMultipleScope or Assert.Multiple they all will run. This allows detecting more than one failure in a single test run. Note that Assert.EnterMultipleScope is the preferred method, but this functionality was released in NUnit 4.2. On older NUnit versions one can use Assert.Multiple.

Without the Assert.EnterMultipleScope the below code will stop executing after the first failure and the second violation won't be detected until the next run when the first one has been corrected.

Assert.That(instance.Property1, Is.EqualTo(expectedProperty1Value));
Assert.That(instance.Property2, Is.EqualTo(expectedProperty2Value));

How to fix violations

Add an Assert.EnterMultipleScope using block surrounding the Assert statements.

using (Assert.EnterMultipleScope())
{
    Assert.That(instance.Property1, Is.EqualTo(expectedProperty1Value));
    Assert.That(instance.Property2, Is.EqualTo(expectedProperty2Value));
};

Using Assert.Multiple then the fix would look like this - where all the independent Assert statements are called from inside the lambda parameter.

Assert.Multiple(() =>
{
    Assert.That(instance.Property1, Is.EqualTo(expectedProperty1Value));
    Assert.That(instance.Property2, Is.EqualTo(expectedProperty2Value));
});

Configure severity

Via ruleset file

Configure the severity per project, for more info see MSDN.

Via .editorconfig file

# NUnit2045: Use Assert.EnterMultipleScope or Assert.Multiple
dotnet_diagnostic.NUnit2045.severity = chosenSeverity

where chosenSeverity can be one of none, silent, suggestion, warning, or error.

Via #pragma directive

#pragma warning disable NUnit2045 // Use Assert.EnterMultipleScope or Assert.Multiple
Code violating the rule here
#pragma warning restore NUnit2045 // Use Assert.EnterMultipleScope or Assert.Multiple

Or put this at the top of the file to disable all instances.

#pragma warning disable NUnit2045 // Use Assert.EnterMultipleScope or Assert.Multiple

Via attribute [SuppressMessage]

[System.Diagnostics.CodeAnalysis.SuppressMessage("Assertion",
    "NUnit2045:Use Assert.EnterMultipleScope or Assert.Multiple",
    Justification = "Reason...")]