This function allows package developers to run tests themselves that should not run on CRAN or with "R CMD check –as-cran" because of compute time constraints with CRAN tests.
a regular expressions to apply to the names of
Assume this is CRAN if at least n_R_CHECK4CRAN elements of
The "Writing R Extensions" manual says that "R CMD check" can be customized "by setting environment variables _R_CHECK_*_:, as described in" the Tools section of the "R Internals" manual.
'R CMD check' was tested with R 3.0.1 under Fedora 18 Linux and with Rtools 3.0 from April 16, 2013 under Windows 7. With the '–as-cran' option, 7 matches were found; without it, only 3 were found. These numbers were unaffected by the presence or absence of the '–timings' parameter. On this basis, the default value of n_R_CHECK4CRAN was set at 5.
1. x. <- Sys.getenv()
n_R_CHECK4CRAN if missing.
3. Let i be the indices of x. whose names match all the patterns in the vector x.
4. Assume this is CRAN if length(i) >= n_R_CHECK4CRAN
a logical scalar with attributes 'Sys.getenv' containing the results
Sys.getenv() and 'matches' contining
i per step 3
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16