Ruby

Date.parse cannot accept incomplete strings whose delimiter is a hyphen like: "2016-12", although it can accept if a delimiter is a slash like: "2016/12"

I'm not really sure if this is a bug or an expected behavior, but a maintainer of rails/rails recommended me to report this to Ruby team when I issued a PR( https://github.com/rails/rails/pull/27181 ) to them. So I'd appreciate if this issue is looked into.

steps to reproduce:

require "date" => true Date.parse("2016/12/01") => #<Date: 2016-12-01 ((2457724j,0s,0n),+0s,2299161j)> Date.parse("2016-12-01") => #<Date: 2016-12-01 ((2457724j,0s,0n),+0s,2299161j)> Date.parse("2016/12") => #<Date: 2016-12-01 ((2457724j,0s,0n),+0s,2299161j)> Date.parse("2016-12") ArgumentError: invalid date from (irb):3:in `parse'	from (irb):3	from /usr/local/bin/irb:11:in `<main>'