[Core] Tighten variation naming

This tightens up the naming distinctions:

 - Variation - The set of VariationOptions defining when the Variant will
be active.
 - Variant - The collective property, Variation and its value.

It also asyncifies the request for Mac

2 files changed, 77 insertions, 9 deletions

diff --git a/Xamarin.PropertyEditing.Tests/CreateVariantViewModelTests.cs b/Xamarin.PropertyEditing.Tests/CreateVariantViewModelTests.cs
index cd87071..2e33114 100644
--- a/Xamarin.PropertyEditing.Tests/CreateVariantViewModelTests.cs
+++ b/Xamarin.PropertyEditing.Tests/CreateVariantViewModelTests.cs
@@ -50,7 +50,7 @@ namespace Xamarin.PropertyEditing.Tests
 		{
 			var property = GetTestProperty (out PropertyVariationOption[] variations);
 			var categories = variations.Select (v => v.Category).Distinct ().ToArray();
-			var vm = new CreateVariationViewModel (property.Object);
+			var vm = new CreateVariantViewModel (property.Object);
 			Assert.That (vm.VariationCategories.Count, Is.EqualTo (categories.Length));
 			CollectionAssert.AreEqual (vm.VariationCategories.Select (v => v.Name), categories);
 		}
@@ -59,7 +59,7 @@ namespace Xamarin.PropertyEditing.Tests
 		public void WhenAllAnyCommandDisabledEnabled ()
 		{
 			var property = GetTestProperty (out PropertyVariationOption[] variations);
-			var vm = new CreateVariationViewModel (property.Object);
+			var vm = new CreateVariantViewModel (property.Object);
 			Assume.That (vm.VariationCategories.All (vvm => vvm.IsAnySelected), Is.True);
 			Assert.That (vm.CreateVariantCommand.CanExecute (null), Is.False);
 
@@ -75,12 +75,12 @@ namespace Xamarin.PropertyEditing.Tests
 		public void CreateVariant ()
 		{
 			var property = GetTestProperty (out PropertyVariationOption[] variations);
-			var vm = new CreateVariationViewModel (property.Object);
-			Assume.That (vm.Variant, Is.Null);
+			var vm = new CreateVariantViewModel (property.Object);
+			Assume.That (vm.Variation, Is.Null);
 
 			bool changed = false;
 			vm.PropertyChanged += (sender, args) => {
-				if (args.PropertyName == nameof (CreateVariationViewModel.Variant))
+				if (args.PropertyName == nameof (CreateVariantViewModel.Variation))
 					changed = true;
 			};
 
@@ -89,10 +89,10 @@ namespace Xamarin.PropertyEditing.Tests
 			vm.CreateVariantCommand.Execute (null);
 
 			Assert.That (changed, Is.True, "Variation did not fire PropertyChanged");
-			Assert.That (vm.Variant, Is.Not.Null);
-			Assert.That (vm.Variant.Count, Is.EqualTo (2));
-			Assert.That (vm.Variant, Contains.Item (vm.VariationCategories[0].Variations[1]));
-			Assert.That (vm.Variant, Contains.Item (vm.VariationCategories[1].Variations[2]));
+			Assert.That (vm.Variation, Is.Not.Null);
+			Assert.That (vm.Variation.Count, Is.EqualTo (2));
+			Assert.That (vm.Variation, Contains.Item (vm.VariationCategories[0].Variations[1]));
+			Assert.That (vm.Variation, Contains.Item (vm.VariationCategories[1].Variations[2]));
 		}
 
 		private Mock<IPropertyInfo> GetTestProperty (out PropertyVariationOption[] options)
diff --git a/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs b/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs
index f1a0d51..84b5d84 100644
--- a/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs
+++ b/Xamarin.PropertyEditing.Tests/PropertyViewModelTests.cs
@@ -1404,6 +1404,74 @@ namespace Xamarin.PropertyEditing.Tests
 		}
 
 		[Test]
+		public void RequestCreateVariant ()
+		{
+			var mockProperty = GetPropertyMock ();
+			mockProperty.SetupGet (v => v.Variations).Returns (new[] { new PropertyVariationOption ("Category", "Value") });
+
+			var target = new object ();
+			var editor = new Mock<IObjectEditor> ();
+			editor.SetTarget (target);
+			editor.Setup (oe => oe.Properties).Returns (new[] { mockProperty.Object });
+			SetupPropertyGet (editor, mockProperty.Object, default(TValue));
+
+			var vm = GetViewModel (mockProperty.Object, editor.Object);
+
+			var variation = new PropertyVariation (new[] { mockProperty.Object.Variations[0] });
+			bool requested = false;
+			vm.CreateVariantRequested += (sender, args) => {
+				requested = true;
+				args.Variation = Task.FromResult (variation);
+			};
+
+			vm.RequestCreateVariantCommand.Execute (null);
+
+			Assert.That (requested, Is.True, "CreateVariantRequested didn't fire");
+			editor.Verify (oe => oe.SetValueAsync (mockProperty.Object, It.IsAny<ValueInfo<TValue>> (), variation));
+		}
+
+		[Test]
+		public void RequestCreateVariantCancel ()
+		{
+			var mockProperty = GetPropertyMock ();
+			mockProperty.SetupGet (v => v.Variations).Returns (new[] { new PropertyVariationOption ("Category", "Value") });
+
+			var target = new object ();
+			var editor = new Mock<IObjectEditor> ();
+			editor.SetTarget (target);
+			editor.Setup (oe => oe.Properties).Returns (new[] { mockProperty.Object });
+			SetupPropertyGet (editor, mockProperty.Object, default (TValue));
+
+			var vm = GetViewModel (mockProperty.Object, editor.Object);
+
+			int t = 0;
+			bool requested = false;
+			vm.CreateVariantRequested += (sender, args) => {
+				requested = true;
+
+				switch (t) {
+				case 0:
+					args.Variation = null;
+					break;
+				case 1:
+					args.Variation = Task.FromCanceled<PropertyVariation> (new CancellationToken (true));
+					break;
+				case 2:
+					args.Variation = Task.FromResult<PropertyVariation> (null);
+					break;
+				}
+
+				t++;
+			};
+
+			for (int i = 0; i < 3; i++) {
+				Assert.That (() => vm.RequestCreateVariantCommand.Execute (null), Throws.Nothing);
+				Assert.That (requested, Is.True, "CreateVariantRequested didn't fire");
+				editor.Verify (oe => oe.SetValueAsync (mockProperty.Object, It.IsAny<ValueInfo<TValue>> (), It.IsAny<PropertyVariation> ()), Times.Never);
+			}
+		}
+
+		[Test]
 		public void CreateBinding ()
 		{
 			var mockProperty = GetPropertyMock ();