CRAN: Test if running as CRAN

Description

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.

Usage

CRAN(CRAN_pattern, n_R_CHECK4CRAN)

Arguments

CRAN_pattern

a regular expressions to apply to the names of Sys.getenv() to identify possible CRAN parameters. Defaults to Sys.getenv('_CRAN_pattern_') if available and '^_R_' if not.

n_R_CHECK4CRAN

Assume this is CRAN if at least n_R_CHECK4CRAN elements of Sys.getenv() have names matching x. Defaults to Sys.getenv('_n_R_CHECK4CRAN_') if available and 5 if not.

Value

a logical scalar with attributes 'Sys.getenv' containing the results of Sys.getenv() and 'matches' contining i per step 3 above.

Details

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()

2. Fix CRAN_pattern and 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

Examples

Run this code

# NOT RUN {
<!-- % Look in fda-ex.Rout -->
# }
# NOT RUN {
<!-- % for the results from R CMD check -->
# }
# NOT RUN {
<!-- % Modified defaults were tested with environment variables -->
# }
# NOT RUN {
<!-- % _CRAN_pattern_ = 'A' and _n_R_CHECK4CRAN_ = '10' -->
# }
# NOT RUN {
<!-- % 'R CMD check' found 26 matches and CRAN() returned TRUE -->
# }
# NOT RUN {
cran <- CRAN()
str(cran)
gete <- attr(cran, 'Sys.getenv')
(ngete <- names(gete))

iget <- grep('^_', names(gete))
gete[iget]

# }
# NOT RUN {
if(CRAN()){
  stop('CRAN')
} else {
  stop('NOT CRAN')
}
# }