all_args_have_default_values and NULL default parameters

[dernst]

I have a driver constructor of this form:

foo = function(driverclass=NULL, classpath=NULL) {
#...
new("foo")
}

which gives the following error when trying to run the tests:

> DBItest::test_all(skip=c("package_name", NULL))
Error: Test failed: 'DBItest: Driver: constructor'
* values must be length 1,
 but FUN(X[[1]]) result is length 0
1: expect_warning(expect_that(constructor, all_args_have_default_values()), NA)
2: quasi_capture(enquo(object), capture_warnings, label = label)
3: capture(act$val <- eval_bare(get_expr(quo), get_env(quo)))
4: withCallingHandlers(code, warning = function(condition) {
       out$push(condition)
       invokeRestart("muffleWarning")
   })
5: eval_bare(get_expr(quo), get_env(quo))
6: expect_that(constructor, all_args_have_default_values())
7: condition(object)
8: expect_true(all(vapply(args, as.character, character(1L)) != ""), "has arguments without default values")
9: quasi_label(enquo(object), label)
10: eval_bare(get_expr(quo), get_env(quo))
11: vapply(args, as.character, character(1L))

Are NULL default parameters not allowed for driver constructors in DBI? The error seems to occur in vapply, the analogous statement with lapply seems to give the expected result.
Thanks.

[krlmlr]

Thanks for reporting!