From the NEWS of R 4.0.0:
R CMD check --as-crannow runs
\donttestexamples (which are run by
example()) instead of instructing the tester to do so. This can be temporarily circumvented during development by setting environment variable
_R_CHECK_DONTTEST_EXAMPLES_to a false value.
In my package, I have a few examples that take ca. 1-3 minutes to run. For me, it would be okay if CRAN would run these, but I am wondering whether long-running examples are now okay on CRAN. Or is there a drop-in replacement for
\donttest? Furthermore, others might have examples that may run even longer ...
There is a related issue in the devtools repo: https://github.com/r-lib/devtools/issues/2216