[No longer updated.]

Checks using older R-devel with

setenv _R_CHECK_LENGTH_1_LOGIC2_ "package:_R_CHECK_PACKAGE_NAME_,abort,verbose"

showing 
 
'length > 1 in coercion to logical'

issues (from using || or &&) in the package under test.

As from 2022-04-26 these are errors in R-devel, but the verbose reports 
can pro tem still be generated by setting that env variable.

(Reproducible also using R 4.1.3. and 4.2.0.)

You should never test class with class(x) == "foo": use inheritsi() or is().

'the condition has length > 1' always gives an error in R 4.2.0 and later.

File ls.txt is a listing of the current (non-archived) packages with logs here.