Fix Time.new keyword arguments on JRuby 10 (#443)

* Fix Time.new with keyword arguments on JRuby 10 and Ruby 3.1+

Replace `ruby2_keywords` approach with explicit `**kwargs` in
`new_with_mock_time`. On JRuby 10 (Ruby 3.4 compat), the
`ruby2_keywords` flag doesn't properly forward keyword arguments
through `new_without_mock_time`, causing `TypeError: no implicit
conversion of Hash into Integer` when ActiveModel deserializes
datetime columns.

The fix uses explicit `**kwargs` which works correctly across all
Ruby versions and implementations.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* replaced rescue ArgumentError with skip + version guard. This ensures a TypeError (or any other error) on older Ruby won't silently mask a failure. Also new test covering kwargs only, no positional args), which exercises the args.empty? && kwargs.any? branch

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: Josh Cronemeyer <joshuacronemeyer@gmail.com>

Author: 3 people

lib/timecop/time_extensions.rb

@@ -18,12 +18,16 @@ def now_with_mock_time
 
     alias_method :new_without_mock_time, :new
 
-    def new_with_mock_time(*args)
-      args.size <= 0 ? now : new_without_mock_time(*args)
+    def new_with_mock_time(*args, **kwargs)
+      if args.empty? && kwargs.empty?
+        now
+      elsif kwargs.any?
+        new_without_mock_time(*args, **kwargs)
+      else
+        new_without_mock_time(*args)
+      end
     end
 
-    ruby2_keywords :new_with_mock_time if Module.private_method_defined?(:ruby2_keywords)
-
     alias_method :new, :new_with_mock_time
   end
 end

test/timecop_test.rb

@@ -519,6 +519,32 @@ def test_mock_time_new_same_as_now
     assert_equal date, Time.new
   end
 
+  def test_time_new_with_keyword_arguments
+    skip "Time.new with in: keyword requires Ruby 3.1+" if RUBY_VERSION < "3.1"
+    Timecop.freeze(2011, 1, 2) do
+      t = Time.new(2020, 1, 1, 0, 0, 0, in: "+05:00")
+      assert_equal 2020, t.year
+      assert_equal 18000, t.utc_offset
+    end
+  end
+
+  def test_time_new_with_only_keyword_arguments
+    skip "Time.new with in: keyword requires Ruby 3.1+" if RUBY_VERSION < "3.1"
+    Timecop.freeze(2011, 1, 2) do
+      t = Time.new(in: "+05:00")
+      assert_equal 18000, t.utc_offset
+    end
+  end
+
+  def test_time_new_with_positional_args_still_works
+    Timecop.freeze(2011, 1, 2) do
+      t = Time.new(2020, 6, 15, 12, 30, 0)
+      assert_equal 2020, t.year
+      assert_equal 6, t.month
+      assert_equal 15, t.day
+    end
+  end
+
   def test_not_callable_send_travel
     assert_raises NoMethodError do
       Timecop.send_travel(:travel, Time.now - 100)