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Merck / metalite

An R package to create metadata structure for ADaM data analysis and reporting
https://merck.github.io/metalite/
GNU General Public License v3.0
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Remove `library()` calls from `tests/testthat/` #160

Closed nanxstats closed 9 months ago

nanxstats commented 9 months ago

From R Packages:

This eliminates the need for any library() calls below tests/testthat/, for the vast majority of R packages. Any instance of library(testthat) is clearly no longer necessary. Likewise, any instance of attaching one of your dependencies via library(somePkg) is unnecessary. In your tests, if you need to call functions from somePkg, do it just as you do below R/. If you have imported the function into your namespace, use fun(). If you have not, use somePkg::fun(). It’s fair to say that library(somePkg) in the tests should be about as rare as taking a dependency via Depends, i.e. there is almost always a better alternative.

Unnecessary calls to library(somePkg) in test files have a real downside, because they actually change the R landscape. library() alters the search path. This means the circumstances under which you are testing may not necessarily reflect the circumstances under which your package will be used. This makes it easier to create subtle test bugs, which you will have to unravel in the future.