test: fs.createReadStream().destroy() fd leak

PR-URL: #56
Reviewed-By: Rod Vagg <rod@vagg.org>

See PR for long discussion

test/parallel/test-fs-read-stream-fd-leak.js

@@ -0,0 +1,66 @@
+// Copyright io.js contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var common = require('../common');
+var assert = require('assert');
+var fs = require('fs');
+var path = require('path');
+
+var openCount = 0;
+var _fsopen = fs.open;
+var _fsclose = fs.close;
+
+var loopCount = 50;
+var emptyTxt = path.join(common.fixturesDir, 'empty.txt');
+
+fs.open = function() {
+  openCount++;
+  return _fsopen.apply(null, arguments);
+}
+
+fs.close = function() {
+  openCount--;
+  return _fsclose.apply(null, arguments);
+}
+
+function testLeak(endFn, callback) {
+  console.log('testing for leaks from fs.createReadStream().%s()...', endFn);
+
+  var i = 0;
+
+  setInterval(function() {
+    var s = fs.createReadStream(emptyTxt);
+    s[endFn]();
+
+    if (++i === loopCount) {
+      clearTimeout(this);
+      setTimeout(function() {
+        assert.equal(0, openCount, 'no leaked file descriptors using ' + endFn + '() (got ' + openCount + ')');
+        openCount = 0;
+        callback && setTimeout(callback, 100);
+      }, 100);
+    }
+  }, 2);
+}
+
+testLeak('close', function() {
+  testLeak('destroy');
+});