Allow @examplesIf snippet to return last value

[dgkf]

Hi! I'm reaching out because of a challenge I'm facing in testex, a package for in-line testing in @examples sections.

It uses a syntax that looks something like this:

#' @examples
#' 1 + 2
#' @test 3
#' @test is.numeric(.)

Tests are generated that run against the last value produced by the previous example expression. However, using @examplesIf is a bit problematic here because it uses withAutoprint() in the generated @examplesIf snippet. This function returns a slightly mutated value, wrapping the result in a list and providing extra information about whether the expression returned visibly.

withAutoprint(1 + 2)
#> 1 + 2
#> [1] 3
.Last.value
#> $value
#> [1] 3
#> 
#> $visible
#> [1] TRUE

Would it be possible to alter the @examplesIf snippet so it returns the result of the examples expression verbatim? If not, I can check for a list with exactly these two names and handle it as a special case, but I don't feel great about introducing heuristics into testing code.