[ruby/csv] CSV(): Add support for Ruby 3 (https://github.com/ruby/csv/pull/215)

The implementation of the `CSV` shortcut method is broken in Ruby 3
for calls that look like this:

```ruby
CSV(write_stream, col_sep: "|", headers: headers, write_headers: true) do |csv|
  ...
end
```

The above will result in the following error when the `CSV` method attempts to pass
on arguments to `CSV#instance`:

```
ArgumentError: wrong number of arguments (given 2, expected 0..1)
```

The issue is due to the changes in Ruby 3 relating to positional & keyword arguments.

This commit updates the `CSV()` shortcut implementation to work with Ruby 3, and also
updates the documentation for the shortcut method.

https://github.com/ruby/csv/commit/310dee45fa

1 files changed, 9 insertions, 0 deletions

diff --git a/test/csv/interface/test_read_write.rb b/test/csv/interface/test_read_write.rb
index 20c9fe317e..c371e9c5fc 100644
--- a/test/csv/interface/test_read_write.rb
+++ b/test/csv/interface/test_read_write.rb
@@ -112,4 +112,13 @@ a;b;c
     assert_equal(CSV.instance,
                  CSV {|csv| csv})
   end
+
+  def test_instance_shortcut_with_io
+    io = StringIO.new
+    from_instance = CSV.instance(io, col_sep: ";") { |csv| csv << ["a", "b", "c"] }
+    from_shortcut = CSV(io, col_sep: ";") { |csv| csv << ["e", "f", "g"] }
+
+    assert_equal(from_instance, from_shortcut)
+    assert_equal(from_instance.string, "a;b;c\ne;f;g\n")
+  end
 end