[release/3.1] Query: Use stronger reflection in Queryable/Enumerable methods (#24090)

[smitpatel]

Resolves #24002

Description

As per dotnet/runtime#28776, there are new queryable/enumerable method overloads of existing methods are being added. We use reflection to get some of the methods which EF Core translates and uses in generating result. Those new overloads could cause error in finding correct method.

Customer Impact

Customers won't be able to use EF Core 3.1 on net6 platform.

How found

Indicated on API proposal by customers.

Test coverage

Whole query pipeline uses both classes so any error in reflection will cause all query tests to fail due to type initialization error.

Regression?

No. This is to make code forward-compatible for platform.

Risk

Very low. All tests verify that current code for reflection is correct. Comparison based on exact type of arguments validates that this would not need to be changed in future.

[ajcvickers]

@smitpatel Were you able to verify whether 2.1 also has this issue?

[smitpatel]

EF Core 2.1 doesn't have this specific issue because the code doesn't exist in 2.1 but it can still get broken mainly because Remotion.Linq parses expression tree for us. And those methods would throw up that library if it is not going reflection propertly.

[ajcvickers]

@smitpatel Have you verified this? If Remotion.Linq does fail, does that mean that any LINQ provider that uses it will fail?

[smitpatel]

Remotion.Linq does not have faulty reflection but it doesn't have specific method selected to generate operations, instead it works with all overloads. It may just work as long new methods are not being used in query. But without running the code it is hard to say for sure.

[wtgodbe]

@smitpatel who should review this? Branches are open until EOD Thursday