/// <summary>
/// Asserts that the specified object does not raise the <see cref="INotifyPropertyChanged.PropertyChanged"/> event.
/// </summary>
/// <typeparam name="TObject">The <see cref="Type">type</see> of <see cref="INotifyPropertyChanged">object</see> to test.</typeparam>
/// <typeparam name="TValue">The <see cref="Type">type</see> of value to assign to the property.</typeparam>
/// <param name="assert">The extended <see cref="Asserter"/>.</param>
/// <param name="subject">The <see cref="INotifyPropertyChanged">object</see> to test.</param>
/// <param name="testProperty">The <see cref="Expression{T}">expression</see> representing the test property.</param>
/// <param name="value">The value to to assign to the tested property.</param>
/// <include file="examples.xml" path="Types/Type[@name='INotifyPropertyChangedExtensions']/Member[@name='PropertyNotChanged`2']/example" />
public static void PropertyNotChanged <TObject, TValue>(this Asserter assert, TObject subject, Expression <Func <TObject, TValue> > testProperty, TValue value) where TObject : INotifyPropertyChanged
{
Arg.NotNull(assert, nameof(assert));
assert.AssertParameterIsNotNull(subject, nameof(subject));
assert.AssertParameterIsNotNull(testProperty, nameof(testProperty));
var changed = false;
var test = subject.GetTestForProperty(assert, testProperty, out var propertyName);
void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
{
changed = true;
propertyName = e.PropertyName;
}
subject.PropertyChanged += OnPropertyChanged;
try
{
test(subject, value);
}
finally
{
subject.PropertyChanged -= OnPropertyChanged;
}
if (string.IsNullOrEmpty(propertyName))
{
assert.IsFalse(changed, AllPropertiesChangedRaised);
}
else
{
assert.IsFalse(changed, PropertyChangedRaised, propertyName);
}
}
