1 files changed, 73 insertions, 0 deletions
diff --git a/test/ruby/test_readpartial.rb b/test/ruby/test_readpartial.rb
new file mode 100644
index 0000000000..bc22556cd4
--- /dev/null
+++ b/test/ruby/test_readpartial.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: false
+require 'test/unit'
+require 'timeout'
+require 'fcntl'
+
+class TestReadPartial < Test::Unit::TestCase
+  def make_pipe
+    r, w = IO.pipe
+    r.binmode
+    w.binmode
+    begin
+      yield r, w
+    ensure
+      r.close unless r.closed?
+      w.close unless w.closed?
+    end
+  end
+
+  def pipe
+    make_pipe {|r, w|
+      yield r, w
+    }
+    return unless defined?(Fcntl::F_SETFL)
+    return unless defined?(Fcntl::F_GETFL)
+    return unless defined?(Fcntl::O_NONBLOCK)
+    make_pipe {|r, w|
+      r.fcntl(Fcntl::F_SETFL, r.fcntl(Fcntl::F_GETFL) | Fcntl::O_NONBLOCK)
+      yield r, w
+    }
+  end
+
+  def test_length_zero
+    pipe {|r, w|
+      assert_equal('', r.readpartial(0))
+    }
+  end
+
+  def test_closed_pipe
+    pipe {|r, w|
+      w << 'abc'
+      w.close
+      assert_equal('ab', r.readpartial(2))
+      assert_equal('c', r.readpartial(2))
+      assert_raise(EOFError) { r.readpartial(2) }
+      assert_raise(EOFError) { r.readpartial(2) }
+    }
+  end
+
+  def test_open_pipe
+    pipe {|r, w|
+      w << 'abc'
+      assert_equal('ab', r.readpartial(2))
+      assert_equal('c', r.readpartial(2))
+      assert_raise(Timeout::Error) {
+        Timeout.timeout(0.1) { r.readpartial(2) }
+      }
+    }
+  end
+
+  def test_with_stdio
+    pipe {|r, w|
+      w << "abc\ndef\n"
+      assert_equal("abc\n", r.gets)
+      w << "ghi\n"
+      assert_equal("de", r.readpartial(2))
+      assert_equal("f\n", r.readpartial(4096))
+      assert_equal("ghi\n", r.readpartial(4096))
+      assert_raise(Timeout::Error) {
+        Timeout.timeout(0.1) { r.readpartial(2) }
+      }
+    }
+  end
+end