Bug #19829: Enumerator.product called with keyword arguments raises exception with not precise message

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: 3.2.1
• Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN

[andrykonchin (Andrew Konchin)]

The Enumerator.product method, added in Ruby 3.2, when it's called with keyword arguments (but it expects only a list of enums) raises unknown keyword: ... (ArgumentError) exception:

Enumerator.product([], a: 1)
# (irb):1:in `product': unknown keyword: :a (ArgumentError)

But AFAIK unknown keyword is used when a method expects keyword arguments and some not supported keyword arguments were passed. So I would expect raising exception with no keywords accepted (ArgumentError) message instead that states clearly that no keywords should be passed.

[jeremyevans0 (Jeremy Evans)]

I submitted a pull request to fix this, by adding an rb_no_keywords_accepted C-API function and using that for both C methods and Ruby methods that do not accept keywords: https://github.com/ruby/ruby/pull/8243

[matz (Yukihiro Matsumoto)]

• Status changed from Open to Closed

I see no benefit from the proposed change, other than you cannot tell the method takes any keyword argument or not at all from the error message.
In that case, I advise reading the document.

Matz.