Analyzer implementation to enhance assertions

[AtolagbeMuiz]

This Pull request fixes #6360

This implementation involves changes to the Analyzer to suggest a much cleaner approach to write Assertions that involves the use of Predicate functions. for example

Assert.IsTrue(_enumerable.Where(x => x == 1).Any());
Assert.IsTrue(_enumerable.Any(x => x == 1));
Assert.IsTrue(_enumerable.Count(x => x == 1) > 0);

Analyzer will suggest (Expected Behaviour)
Assert.Contains(x => x == 1, _enumerable);

Example 2:

Assert.IsFalse(_enumerable.Where(x => x == 1).Any());
Assert.IsFalse(_enumerable.Any(x => x == 1));
Assert.IsFalse(_enumerable.Count(x => x == 1) > 0);

Analyzer will suggest (Expected Behaviour)
Assert.DoesNotContain(x => x == 1, _enumerable);

[stan-sz]

Consider adding SingleAny and SingleCount for the .Single() Linq extension method.

[AtolagbeMuiz]

is this just to add it as part of the enums because, there is no use of it for now in the codebase except if we have an issue that wants the analyzer to check for predicate that uses Single Linq

@Youssef1313 thoughts on this?

[stan-sz]

I meant full support of .Single() in this analyzer.

[AtolagbeMuiz]

ohh okay.. please can you provide sample code of how it can be used and the expected suggestion code we want analyzer to give..

just to make sure we are on the same page. thank you.

[cremor]

I can see a few cases, but I'm not sure if they make sense. In all those cases the thrown exception would change at least in one of the possible failure cases. (And those old assertions are not good to start with.)
That's also why I didn't include those when I initially wrote the issue.

// Expected analyzer suggestion:
//Assert.ContainsSingle(x => x == 1, _enumerable);

// Questionable:
Assert.IsNotNull(_enumerable.Where(x => x == 1).SingleOrDefault());
Assert.IsNotNull(_enumerable.SingleOrDefault(x => x == 1));

// Even more questionable:
Assert.IsNotNull(_enumerable.Where(x => x == 1).Single());
Assert.IsNotNull(_enumerable.Single(x => x == 1));

// Expected analyzer suggestion:
//Assert.DoesNotContain(x => x == 1, _enumerable);

// Questionable:
Assert.IsNull(_enumerable.Where(x => x == 1).SingleOrDefault());
Assert.IsNull(_enumerable.SingleOrDefault(x => x == 1));

[AtolagbeMuiz]

the pull request is now updated with the requested changes.. analyzer has been updated for Single and SingleOrDefault @stan-sz @cremor