public void FirstOrDefault_ObservableSourceNewFirstItemAdded_Update()
{
var update = false;
var coll = new NotifyCollection <string>()
{
"23"
};
var test = Observable.Expression(() => coll.FirstOrDefault());
test.ValueChanged += (o, e) =>
{
update = true;
Assert.AreEqual("42", e.NewValue);
Assert.AreEqual("23", e.OldValue);
};
Assert.AreEqual("23", test.Value);
Assert.IsFalse(update);
coll.Insert(0, "42");
Assert.IsTrue(update);
Assert.AreEqual("42", test.Value);
}
public void PredicateFirstOrDefault_ObservableSourceFirstItemAdded_NoUpdateWhenDetached()
{
var update = false;
var coll = new NotifyCollection <string>()
{
"1"
};
var test = Observable.Expression(() => coll.FirstOrDefault(s => s.Length > 1));
test.ValueChanged += (o, e) => update = true;
Assert.IsNull(test.Value);
Assert.IsFalse(update);
test.Detach();
update = false;
coll.Add("42");
Assert.IsFalse(update);
test.Attach();
Assert.IsTrue(update);
Assert.AreEqual("42", test.Value);
update = false;
coll.Remove("42");
Assert.IsTrue(update);
}
public void PredicateFirstOrDefault_ObservableSourceRemoveNewFirstItem_Update()
{
var update = false;
var coll = new NotifyCollection <string>()
{
"1", "42", "23"
};
var test = Observable.Expression(() => coll.FirstOrDefault(s => s.Length > 1));
test.ValueChanged += (o, e) =>
{
update = true;
Assert.AreEqual("42", e.OldValue);
Assert.AreEqual("23", e.NewValue);
};
Assert.AreEqual("42", test.Value);
Assert.IsFalse(update);
coll.Remove("42");
Assert.IsTrue(update);
Assert.AreEqual("23", test.Value);
}
public void ReversableFirstOrDefault_SetToNull_Correct()
{
var collection = new NotifyCollection <string>()
{
"a", "b", "c"
};
SetValue(() => collection.FirstOrDefault(), null);
Assert.AreEqual(0, collection.Count);
}
public void ReversableFirstOrDefault_WithPredicate_SetToNull_Correct()
{
var collection = new NotifyCollection <string>()
{
"a", "b", "c"
};
SetValue(() => collection.FirstOrDefault(s => string.Compare(s, "a") > 0), null);
Assert.AreEqual(1, collection.Count);
Assert.IsTrue(collection.Contains("a"));
}
public void ReversableFirstOrDefault_SetToExistingItem_Correct()
{
var collection = new NotifyCollection <string>()
{
"a", "b", "c"
};
SetValue(() => collection.FirstOrDefault(), "b");
Assert.AreEqual(3, collection.Count);
Assert.IsTrue(collection.Contains("a"));
Assert.IsTrue(collection.Contains("b"));
Assert.IsTrue(collection.Contains("c"));
}
public void ReversableFirstOrDefault_WithPredicate_SetToOtherItem_Correct()
{
INotifyCollection <string> collection = new NotifyCollection <string>()
{
"a", "b", "c"
};
SetValue(() => collection.FirstOrDefault(s => string.Compare(s, "a") > 0), "d");
Assert.AreEqual(4, collection.Count);
Assert.IsTrue(collection.Contains("a"));
Assert.IsTrue(collection.Contains("b"));
Assert.IsTrue(collection.Contains("c"));
Assert.IsTrue(collection.Contains("d"));
}
public void FirstOrDefault_ObservableSourceOtherItemAdded_NoUpdate()
{
var update = false;
var coll = new NotifyCollection<string>() { "23" };
var test = Observable.Expression(() => coll.FirstOrDefault());
test.ValueChanged += (o, e) => update = true;
Assert.AreEqual("23", test.Value);
Assert.IsFalse(update);
coll.Add("42");
Assert.IsFalse(update);
}
public void FirstOrDefault_ObservableSourceOtherItemAdded_NoUpdate()
{
var update = false;
var coll = new NotifyCollection <string>()
{
"23"
};
var test = Observable.Expression(() => coll.FirstOrDefault());
test.ValueChanged += (o, e) => update = true;
Assert.AreEqual("23", test.Value);
Assert.IsFalse(update);
coll.Add("42");
Assert.IsFalse(update);
}
public void FirstOrDefault_ObservableSourceNewFirstItemAdded_Update()
{
var update = false;
var coll = new NotifyCollection<string>() { "23" };
var test = Observable.Expression(() => coll.FirstOrDefault());
test.ValueChanged += (o, e) =>
{
update = true;
Assert.AreEqual("42", e.NewValue);
Assert.AreEqual("23", e.OldValue);
};
Assert.AreEqual("23", test.Value);
Assert.IsFalse(update);
coll.Insert(0, "42");
Assert.IsTrue(update);
Assert.AreEqual("42", test.Value);
}
public void PredicateFirstOrDefault_ObservableSourceFirstItemAdded_NoUpdateWhenDetached()
{
var update = false;
var coll = new NotifyCollection<string>() { "1" };
var test = Observable.Expression(() => coll.FirstOrDefault(s => s.Length > 1));
test.ValueChanged += (o, e) => update = true;
Assert.IsNull(test.Value);
Assert.IsFalse(update);
test.Detach();
update = false;
coll.Add("42");
Assert.IsFalse(update);
test.Attach();
Assert.IsTrue(update);
Assert.AreEqual("42", test.Value);
update = false;
coll.Remove("42");
Assert.IsTrue(update);
}
public void PredicateFirstOrDefault_ObservableSourceOtherItemRemoved_NoUpdate()
{
var update = false;
var coll = new NotifyCollection<string>() { "1", "23", "42" };
var test = Observable.Expression(() => coll.FirstOrDefault(s => s.Length > 1));
test.ValueChanged += (o, e) => update = true;
Assert.AreEqual("23", test.Value);
Assert.IsFalse(update);
coll.Remove("42");
Assert.IsFalse(update);
}
public void PredicateFirstOrDefault_ObservableSourceFirstItemAdded_Update()
{
var update = false;
var coll = new NotifyCollection<string>() { "1" };
var test = Observable.Expression(() => coll.FirstOrDefault(s => s.Length > 1));
test.ValueChanged += (o, e) =>
{
update = true;
Assert.AreEqual("42", e.NewValue);
Assert.IsNull(e.OldValue);
};
Assert.IsNull(test.Value);
Assert.IsFalse(update);
coll.Add("42");
Assert.IsTrue(update);
Assert.AreEqual("42", test.Value);
}
public IEnumerable <T> GetSequenceForItem(T item)
{
return(Sequences.FirstOrDefault(s => s.Contains(item)));
}