As with many of these posts - this is more of a “note to self”.
Say you have an assertion that looks something like this in your Xunit test:
Assert.True(myEnumerable.Any(a => a.MyValue == "1234"));
In later versions (not sure exactly which one this was introduced it), you’ll get the following warning:
warning xUnit2012: Do not use Enumerable.Any() to check if a value exists in a collection.
So, Xunit has a nice little feature where you can use the following syntax instead:
Assert.Contains(myEnumerable, a => a.MyValue == "1234");