lineno= is not returning an integer
The call-seq for
argf_set_lineno says it returns an
integer, but in fact it returns
p ARGF.send(:lineno=, 1)
IO, the input integer value is returned as documented.
p File.open(__FILE__).send(:lineno=, 1)
ARGF should also return the input value.
I think it is so trivial, but I'm having a little trouble with (adding ARGF to rbs)[https://github.com/ruby/rbs/pull/975].