Add template methods around DbConnection inside RelationalConnection

[joaopgrassi]

Resolves #21327

[joaopgrassi]

There's a test failing (RelationalApiConsistencyTest) due to the newly added template method for DbConnection.CloseAsync()... Not sure how to proceed. The method is protected, so I can't add to the exclusion list (AsyncMethodExceptions). If I make it public then it's not consistent with the rest of the template methods.. and just adding the cancellation token to make the tests pass seems hacky (since it's not used by DbConnection.CloseAsync). Any ideas?

[ajcvickers]

@dotnet/efteam Any thoughts on naming these template methods before merging? (We will review in API review later anyway.)

[ajcvickers]

@joaopgrassi You should be able to add the method to AsyncMethodExceptions even though it is protected. Something like:

typeof(RelationalConnection).GetMethod("CreateDbConnection", BindingFlags.Instance | BindingFlags.NonPublic);

[joaopgrassi]

typeof(RelationalConnection).GetMethod("CreateDbConnection", BindingFlags.Instance | BindingFlags.NonPublic);

Right 😅. Was so deep into the errors forgot the obvious, lol.

I did notice though that some methods return a ValueTask but they were not being caught by this consistency check. Looking more I saw that's because inside Async_methods_should_have_overload_with_cancellation_token_and_end_with_async_suffix it just looks for Task. Not sure if it's something to change as well.. probably not now since it will produce errors everywhere.

[ajcvickers]

@joaopgrassi Thanks for the contribution!