Bug #14176: Unclear error message when calling method with keyword arguments

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 2.4.2p198 (2017-09-14 revision 59899) [x86_64-darwin17]
• Backport: 2.3: UNKNOWN, 2.4: UNKNOWN

[vfonic (Viktor Fonic)]

I (wrongly) created a method with the following signature:

def asd(first, options: {}); end

(notice that options is a keyword argument)

I called the method this way:

asd(arg, options)

And got the following misleading error:
ArgumentError: wrong number of arguments (given 2, expected 1)

It took me some time to realize that the options argument is a keyword argument:

method(:asd)
Object#asd(first, ?)

It would be much more helpful if the error would mention this:
ArgumentError: wrong number of arguments (given 2, expected 1 and 1 keyword argument: options)

Thanks!

[marcandre (Marc-Andre Lafortune)]

Note that Ruby 2.5 improves this since #13196 if options has only symbol keys:

asd(42, {a:1})  # => ArgumentError: unknown keyword: a

I agree the message could still be improved as you suggest.

[marcandre (Marc-Andre Lafortune)]

• Related to Bug #13196: Improve keyword argument errors when non-keyword arguments given added

[marcandre (Marc-Andre Lafortune)]

• Subject changed from Calling method with keyword arguments inconsistent behavior to Unclear error message when calling method with keyword arguments

[jeremyevans0 (Jeremy Evans)]

• Status changed from Open to Closed

With the separation of keyword arguments and positional arguments in #14183, I think this can be closed.