Ruby

[ruby/prism] Fix a diagnostic incompatibility

This PR fixes a diagnostic incompatibility when using no anonymous keyword rest parameter:

foo(**) 

Note, although the actual update applies only to the foo(**) case, for reference,
foo(*) and `foo(&) are also mentioned below.

Ruby (Expected)¶

$ ruby -cve 'foo(*)' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] -e:1: no anonymous rest parameter -e: compile error (SyntaxError) $ ruby -cve 'foo(**)' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] -e:1: no anonymous keyword rest parameter -e: compile error (SyntaxError) $ ruby -cve 'foo(&)' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] -e:1: no anonymous block parameter -e: compile error (SyntaxError) 

Prism (Actual)¶

Before:

$ bundle exec ruby -Ilib -rprism -wve 'p Prism.parse("foo(*)").errors' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] [#<Prism::ParseError @type=:argument_no_forwarding_star @message="unexpected `*` when the parent method is not forwarding" @location=#<Prism::Location @start_offset=4 @length=1 start_line=1> @level=:fatal>]  $ bundle exec ruby -Ilib -rprism -wve 'p Prism.parse("foo(**)").errors' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] [#<Prism::ParseError @type=:expect_expression_after_splat_hash @message="expected an expression after `**` in a hash" @location=#<Prism::Location @start_offset=4 @length=2 start_line=1> @level=:fatal>]  $ bundle exec ruby -Ilib -rprism -wve 'p Prism.parse("foo(&)").errors' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] [#<Prism::ParseError @type=:argument_no_forwarding_amp @message="unexpected `&` when the parent method is not forwarding" @location=#<Prism::Location @start_offset=4 @length=1 start_line=1> @level=:fatal>] 

After:

$ bundle exec ruby -Ilib -rprism -wve 'p Prism.parse("foo(*)").errors' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] [#<Prism::ParseError @type=:argument_no_forwarding_star @message="unexpected `*` when the parent method is not forwarding" @location=#<Prism::Location @start_offset=4 @length=1 start_line=1> @level=:fatal>]  $ bundle exec ruby -Ilib -rprism -wve 'p Prism.parse("foo(**)").errors' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] [#<Prism::ParseError @type=:argument_no_forwarding_star_star @message="unexpected `**` when the parent method is not forwarding" @location=#<Prism::Location @start_offset=4 @length=2 start_line=1> @level=:fatal>]  $ bundle exec ruby -Ilib -rprism -wve 'p Prism.parse("foo(&)").errors' ruby 3.3.0 (2023-12-25 revision https://github.com/ruby/prism/commit/5124f9ac75) [x86_64-darwin22] [#<Prism::ParseError @type=:argument_no_forwarding_amp @message="unexpected `&` when the parent method is not forwarding" @location=#<Prism::Location @start_offset=4 @length=1 start_line=1> @level=:fatal>] 

https://github.com/ruby/prism/commit/633c9d9fd4