1 files changed, 32 insertions, 0 deletions
diff --git a/test/-ext-/wait/test_wait.rb b/test/-ext-/wait/test_wait.rb
new file mode 100644
index 0000000000..79127c041b
--- /dev/null
+++ b/test/-ext-/wait/test_wait.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: false
+require 'test/unit'
+
+class TestWait < Test::Unit::TestCase
+  require '-test-/wait'
+
+  def test_wait_for_valid_fd
+    IO.pipe do |r,w|
+      rc = IO.io_wait(w, IO::WRITABLE, nil)
+      assert_equal IO::WRITABLE, rc
+    end
+  end
+
+  def test_wait_for_invalid_fd
+    r, w = IO.pipe
+    r.close
+
+    IO.for_fd(w.fileno).close
+
+    assert_raise(Errno::EBADF) do
+      IO.io_wait(w, IO::WRITABLE, nil)
+    end
+  end
+
+  def test_wait_for_closed_pipe
+    IO.pipe do |r,w|
+      w.close
+      rc = IO.io_wait(r, IO::READABLE, nil)
+      assert_equal IO::READABLE, rc
+    end
+  end
+end