False Constraint

FalseConstraint tests that a value is false. Use this constraint when asserting that a boolean condition or expression evaluates to false.

Usage

Is.False
Is.Not.False  // equivalent to Is.True

Examples

[Test]
public void FalseConstraint_Examples()
{
    Assert.That(2 + 2 == 5, Is.False);
    var isDisabled = false;
    Assert.That(isDisabled, Is.False);
    ICollection<int> list = new List<int>();
    Assert.That(list.IsReadOnly, Is.False);

    // With nullable booleans
    bool? isDeleted = false;
    Assert.That(isDeleted, Is.False);
}

Notes

  1. Is.Not.False is equivalent to Is.True for non-nullable booleans.
  2. For nullable booleans (bool?), Is.False only passes when the value is exactly false, not when it's null.

See Also