Meteor 3.0 migration considerations

[klablink]

In preparation for the porting of the package to version 3.0, I would like to share how we should behave. To understand the context, I have prepared a simple table with the availability of mongo methods in the various versions:

Mongo methods	pre 2.12	2.12/2.13	3.0
Async server-side	NA	X*	X
No Async server-side	X	X	NA
Async client-side	NA	X*	X
No Async client-side	X	X	X

• NA=Not available
• * With a mutation that use a Promise.resolve.

My question is as follows: is it worth supporting all cases both client-side and server-side, or is it better to focus on the asynchronous variant alone? Writing all tests for all combinations, even the deprecated ones, may not make sense. What do you think?

[github-actions]

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