[R-pkg-devel] new/slightly mysterious CRAN warnings

[Ben Bolker]

   Submission of most recent version of lme4 threw a NOTE on CRAN's 
Debian platform that we had not seen when running "R CMD check 
--as-cran" with the most recent SVN checkout, nor when submitted to 
win-builder/R-devel.  These are legitimate issues (all now fixed), but 
we were taken by surprise because they weren't detected on any platforms 
we tested on.

   So far, archaeology in the R code base/Github mirror about recent 
changes to tools::checkS3methods, or about environment variables, hasn't 
been entirely successful, although based on

grep Sys.getenv src/library/tools/R/QC.R  | sed -e 's/.*Sys.getenv("//' 
| sed -e 's/"[,)].*//' | sort | uniq

it looks like we *might* want to set

_R_CHECK_S3_METHODS_SHOW_POSSIBLE_ISSUES_

when testing ...

   This is mostly a heads-up/documentation for anyone who might be 
interested.


Debian: 
<https://win-builder.r-project.org/incoming_pretest/lme4_1.1-33_20230421_145951/Debian/00check.log>

  R Under development (unstable) (2023-04-20 r84291)

  NOTE
Mismatches for apparent methods not registered:
print:
   function(x, ...)
print.bootWarnings:
   function(x, verbose)

format:
   function(x, ...)
format.perc:
   function(probs, digits)

Apparent methods for exported generics not registered:
   ngrps.default
See section ‘Registering S3 methods’ in the ‘Writing R Extensions’
manual.