NUnit2008

Incorrect IgnoreCase usage

Description

The IgnoreCase modifier should only be used for string or char arguments. Using it on another type will not have any effect.

Motivation

To bring developers' attention to a scenario in which their code is actually having no effect and may reveal that their test is not doing what they expect.

How to fix violations

Example Violation

[Test]
public void NUnit2008SampleTest()
{
    var date = DateTime.Now;
    Assert.That(date, Is.Not.EqualTo(date.AddDays(1)).IgnoreCase);
}

Explanation

Using IgnoreCase here doesn't make any sense, because the types we're comparing don't have the concept of case. Therefore, it's only suitable to use on textual primitives (e.g. string and char).

Fix

Remove the errant call to IgnoreCase:

[Test]
public void NUnit2008SampleTest()
{
    var date = DateTime.Now;
    Assert.That(date, Is.Not.EqualTo(date.AddDays(1)));
}

Or update the code to compare based on the primitives that are supported by IgnoreCase:

[Test]
public void NUnit2008SampleTest()
{
    var date = DateTime.Now;
    Assert.That(date.ToString(), Is.Not.EqualTo(date.AddDays(1).ToString()).IgnoreCase);
}

Configure severity

Via ruleset file

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

Via .editorconfig file

# NUnit2008: Incorrect IgnoreCase usage
dotnet_diagnostic.NUnit2008.severity = chosenSeverity

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

Via #pragma directive

#pragma warning disable NUnit2008 // Incorrect IgnoreCase usage
Code violating the rule here
#pragma warning restore NUnit2008 // Incorrect IgnoreCase usage

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

#pragma warning disable NUnit2008 // Incorrect IgnoreCase usage

Via attribute [SuppressMessage]

[System.Diagnostics.CodeAnalysis.SuppressMessage("Assertion",
    "NUnit2008:Incorrect IgnoreCase usage",
    Justification = "Reason...")]