public void RelayCommandOfT_Ctor_EmptyPredicate_CanAlwaysExecute()
{
// Setup
var command = new RelayCommand<object>(x => { });
// Act + Verify
Assert.IsTrue(command.CanExecute(null));
}
public void RelayCommand_Ctor_EmptyPredicate_CanAlwaysExecute()
{
// Setup
var command = new RelayCommand(() => { });
// Act + Verify
Assert.IsTrue(command.CanExecute());
}
public void ContextualCommandViewModel_Ctor_NullArgChecks()
{
var command = new RelayCommand(() => { });
ContextualCommandViewModel suppressAnalysisWarning;
Exceptions.Expect<ArgumentNullException>(() =>
{
suppressAnalysisWarning = new ContextualCommandViewModel(null, command);
});
}
/// <summary>
/// Creates an instance of contextual command view model
/// </summary>
/// <param name="fixedContext">Required context</param>
/// <param name="command">Optional real command to trigger and pass the fixed context to</param>
public ContextualCommandViewModel(object fixedContext, ICommand command)
{
if (fixedContext == null)
{
throw new ArgumentNullException(nameof(fixedContext));
}
this.fixedContext = fixedContext;
this.proxyCommand = new RelayCommand(this.Execute, this.CanExecute);
this.SetCommand(command);
}
public void ContextualCommandViewModel_CommandInvocation()
{
// Setup
bool canExecute = false;
bool executed = false;
var realCommand = new RelayCommand<object>(
(state) =>
{
Assert.AreEqual(this, state);
executed = true;
},
(state) =>
{
Assert.AreEqual(this, state);
return canExecute;
});
var testSubject = new ContextualCommandViewModel(this, realCommand);
// Sanity
Assert.IsNotNull(testSubject.Command);
Assert.AreSame(realCommand, testSubject.InternalRealCommand);
// Case 1: Can't execute
canExecute = false;
// Act
Assert.IsFalse(testSubject.Command.CanExecute(null), "CanExecute wasn't called as expected");
// Case 2: Can execute
canExecute = true;
// Act
Assert.IsTrue(testSubject.Command.CanExecute(null), "CanExecute wasn't called as expected");
// Case 3: Execute
// Act
testSubject.Command.Execute(null);
Assert.IsTrue(executed, "Execute wasn't called as expected");
}
public void ContextualCommandViewModel_DisplayText()
{
// Setup
var context = new object();
var command = new RelayCommand(() => { });
var testSubject = new ContextualCommandViewModel(context, command);
using (var tracker = new PropertyChangedTracker(testSubject))
{
// Case 1: null
// Act + Verify
Assert.IsNull(testSubject.DisplayText, "Expected display text to return null when not set");
// Case 2: static
testSubject.DisplayText = "foobar9000";
// Act + Verify
Assert.AreEqual("foobar9000", testSubject.DisplayText, "Unexpected static display text");
tracker.AssertPropertyChangedRaised(nameof(testSubject.DisplayText), 1);
// Case 3: dynamic
var funcInvoked = false;
Func<object, string> func = x =>
{
funcInvoked = true;
return "1234";
};
testSubject.SetDynamicDisplayText(func);
// Act + Verify
Assert.AreEqual("1234", testSubject.DisplayText, "Unexpected dynamic display text");
Assert.IsTrue(funcInvoked, "Dynamic display text function was not invoked");
tracker.AssertPropertyChangedRaised(nameof(testSubject.DisplayText), 2);
}
// Case 4: dynamic - null exception
Exceptions.Expect<ArgumentNullException>(() => testSubject.SetDynamicDisplayText(null));
}
public void ContextualCommandViewModel_Icon()
{
// Setup
var context = new object();
var command = new RelayCommand(() => { });
var testSubject = new ContextualCommandViewModel(context, command);
using (var tracker = new PropertyChangedTracker(testSubject))
{
// Case 1: null
// Act + Verify
Assert.IsNull(testSubject.Icon, "Expected icon to return null when not set");
// Case 2: static
var staticIcon = new IconViewModel(null);
testSubject.Icon = staticIcon;
// Act + Verify
Assert.AreSame(staticIcon, testSubject.Icon, "Unexpected static icon");
tracker.AssertPropertyChangedRaised(nameof(testSubject.Icon), 1);
// Case 3: dynamic
var dynamicIcon = new IconViewModel(null);
var funcInvoked = false;
Func<object, IconViewModel> func = x =>
{
funcInvoked = true;
return dynamicIcon;
};
testSubject.SetDynamicIcon(func);
// Act + Verify
Assert.AreSame(dynamicIcon, testSubject.Icon, "Unexpected dynamic icon");
Assert.IsTrue(funcInvoked, "Dynamic icon function was not invoked");
tracker.AssertPropertyChangedRaised(nameof(testSubject.Icon), 2);
}
// Case 4: dynamic - null exception
Exceptions.Expect<ArgumentNullException>(() => testSubject.SetDynamicIcon(null));
}
