NUnit2043

Use ComparisonConstraint for better assertion messages in case of failure

Topic	Value
Id	NUnit2043
Severity	Info
Enabled	True
Category	Assertion
Code	ComparisonConstraintUsageAnalyzer

Description

Using ComparisonConstraint will lead to better assertion messages in case of failure.

Motivation

Using Is.GreaterThan constraint will lead to better assertion messages in case of failure, so this analyzer marks all usages of a comparison operators >, >=, < and <= where it is possible to replace with the appropriate comparison constraint.

[Test]
public void Test()
{
    Assert.True(actual > expected);
}

How to fix violations

The analyzer comes with a code fix that will replace Assert.True(actual > expected) with Assert.That(actual, Is.GreaterThan(expected)). So the code block above will be changed into

[Test]
public void Test()
{
    Assert.That(actual, Is.GreaterThan(expected));
}

Configure severity

Via ruleset file

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

Via .editorconfig file

# NUnit2043: Use ComparisonConstraint for better assertion messages in case of failure
dotnet_diagnostic.NUnit2043.severity = chosenSeverity

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

Via #pragma directive

#pragma warning disable NUnit2043 // Use ComparisonConstraint for better assertion messages in case of failure
Code violating the rule here
#pragma warning restore NUnit2043 // Use ComparisonConstraint for better assertion messages in case of failure

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

#pragma warning disable NUnit2043 // Use ComparisonConstraint for better assertion messages in case of failure

Via attribute [SuppressMessage]

[System.Diagnostics.CodeAnalysis.SuppressMessage("Assertion",
    "NUnit2043:Use ComparisonConstraint for better assertion messages in case of failure",
    Justification = "Reason...")]