[ruby/pathname] Fix segfault of Pathname#split

Fix segmentation fault of Pathname#split when File.split returns
non array value [Bug #17755]

https://github.com/ruby/pathname/commit/e29b49e3b1
https://github.com/ruby/pathname/commit/1db7479a74

1 files changed, 15 insertions, 0 deletions

diff --git a/test/pathname/test_pathname.rb b/test/pathname/test_pathname.rb
index 46a04ee2b6..8a0f3cbb66 100644
--- a/test/pathname/test_pathname.rb
+++ b/test/pathname/test_pathname.rb
@@ -1067,6 +1067,21 @@ class TestPathname < Test::Unit::TestCase
 
   def test_split
     assert_equal([Pathname("dirname"), Pathname("basename")], Pathname("dirname/basename").split)
+
+    assert_separately([], <<-'end;')
+      require 'pathname'
+
+      mod = Module.new do
+        def split(_arg)
+        end
+      end
+
+      File.singleton_class.prepend(mod)
+
+      assert_raise(TypeError) do
+        Pathname('/').split
+      end
+    end;
   end
 
   def test_blockdev?