merge revision(s) d118c84b0b9110462e479487ffaf175a75e5718e: [Backport #15199]

	Fix IO#scanf on pipes on Windows

	IO.seek on a pipe on Windows raises Errno::EINVAL instead of
	Errno::ESPIPE.

	Fixes Ruby Bug #15199

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67754 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 7 insertions, 0 deletions

diff --git a/test/scanf/test_scanfio.rb b/test/scanf/test_scanfio.rb
index cec8750aef..f7c439276d 100644
--- a/test/scanf/test_scanfio.rb
+++ b/test/scanf/test_scanfio.rb
@@ -17,5 +17,12 @@ class TestScanfIO < Test::Unit::TestCase
   ensure
     fh.close
   end
+
+  def test_pipe_scanf
+    r, w = IO.pipe
+    w.write('a')
+    w.close
+    assert_equal([], r.scanf('a'))
+  end
 end