BigDecimal#round returns different types depending on argument
BigDecimal#round returns Integer when no arguments are given and BigDecimal otherwise. I would have assumed the result to always be BigDecimal.
BigDecimal.new('12.34').round # => 12 (Integer)
BigDecimal.new('12.34').round(0) # => 12 (BigDecimal)
Attached is a patch with possible fix.
I found a similar issue to this one (https://bugs.ruby-lang.org/issues/2662), but it's in Japanese. If this should be rejected as well could someone provide an explanation in English please? Also in that case documentation should be changed as it clearly states that the result should be BigDecimal: "Round to the nearest integer (by default), returning the result as a BigDecimal."