Julia: RFC: testset should use `try` rather than `begin`

[vtjnash]

Currently Test.@testset requires a begin/end statement. This can be confusing since in actuality it needs to introduce a new scope block (due to emitting inside a try/catch). It would be a better semantic match for this to require using let instead.

julia> @testset "embedding example" let
           x = 1
       end
ERROR: Expected begin/end block or for loop as argument to @testset

[bramtayl]

What about try?

[garrison]

What about try?

Does try/end behave identically to let/end? I believe I would still prefer let/end, as (in my opinion) it makes most sense to use try only in places with catch and/or finally blocks.

[StefanKarpinski]

It should be try since one testset failing should not stop the following ones from running.

[tkelman]

The @testset macro already puts a try-catch in the code that it generates, so maybe we should find a way to append the normal test handling code around the user's try. Should we add it to the user's code, or error, if a user wants to do something in their own catch or finally after a @testset try?

[vtjnash]

I'm recommending it should require use of exactly try/end to "let the user see" that the testset macro is going to wrap it thusly.

[KristofferC]

Why would I care how the test macro is implemented internally? I haven't sern much confusion arising from this.