Add m-esr52 at 52.6.0

13 files changed, 1851 insertions, 0 deletions

diff --git a/toolkit/components/osfile/tests/mochi/.eslintrc.js b/toolkit/components/osfile/tests/mochi/.eslintrc.js
new file mode 100644
index 000000000..8c0f4f574
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/.eslintrc.js
@@ -0,0 +1,7 @@
+"use strict";
+
+module.exports = {
+  "extends": [
+    "../../../../../testing/mochitest/chrome.eslintrc.js"
+  ]
+};
diff --git a/toolkit/components/osfile/tests/mochi/chrome.ini b/toolkit/components/osfile/tests/mochi/chrome.ini
new file mode 100644
index 000000000..1da463316
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/chrome.ini
@@ -0,0 +1,15 @@
+[DEFAULT]
+skip-if = os == 'android'
+support-files =
+  main_test_osfile_async.js
+  worker_handler.js
+  worker_test_osfile_comms.js
+  worker_test_osfile_front.js
+  worker_test_osfile_shared.js
+  worker_test_osfile_unix.js
+  worker_test_osfile_win.js
+
+[test_osfile_async.xul]
+[test_osfile_back.xul]
+[test_osfile_comms.xul]
+[test_osfile_front.xul]
diff --git a/toolkit/components/osfile/tests/mochi/main_test_osfile_async.js b/toolkit/components/osfile/tests/mochi/main_test_osfile_async.js
new file mode 100644
index 000000000..b940a032a
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/main_test_osfile_async.js
@@ -0,0 +1,443 @@
+"use strict";
+
+Components.utils.import("resource://gre/modules/osfile.jsm");
+Components.utils.import("resource://gre/modules/Promise.jsm");
+Components.utils.import("resource://gre/modules/Task.jsm");
+Components.utils.import("resource://gre/modules/AsyncShutdown.jsm");
+
+// The following are used to compare against a well-tested reference
+// implementation of file I/O.
+Components.utils.import("resource://gre/modules/NetUtil.jsm");
+Components.utils.import("resource://gre/modules/FileUtils.jsm");
+Components.utils.import("resource://gre/modules/Services.jsm");
+
+var myok = ok;
+var myis = is;
+var myinfo = info;
+var myisnot = isnot;
+
+var isPromise = function ispromise(value) {
+  return value != null && typeof value == "object" && "then" in value;
+};
+
+var maketest = function(prefix, test) {
+  let utils = {
+    ok: function ok(t, m) {
+      myok(t, prefix + ": " + m);
+    },
+    is: function is(l, r, m) {
+      myis(l, r, prefix + ": " + m);
+    },
+    isnot: function isnot(l, r, m) {
+      myisnot(l, r, prefix + ": " + m);
+    },
+    info: function info(m) {
+      myinfo(prefix + ": " + m);
+    },
+    fail: function fail(m) {
+      utils.ok(false, m);
+    },
+    okpromise: function okpromise(t, m) {
+      return t.then(
+        function onSuccess() {
+          util.ok(true, m);
+        },
+        function onFailure() {
+          util.ok(false, m);
+        }
+      );
+    }
+  };
+  return function runtest() {
+    utils.info("Entering");
+    try {
+      let result = test.call(this, utils);
+      if (!isPromise(result)) {
+        throw new TypeError("The test did not return a promise");
+      }
+      utils.info("This was a promise");
+      // The test returns a promise
+      result = result.then(function test_complete() {
+        utils.info("Complete");
+      }, function catch_uncaught_errors(err) {
+        utils.fail("Uncaught error " + err);
+        if (err && typeof err == "object" && "message" in err) {
+          utils.fail("(" + err.message + ")");
+        }
+        if (err && typeof err == "object" && "stack" in err) {
+          utils.fail("at " + err.stack);
+        }
+      });
+      return result;
+    } catch (x) {
+      utils.fail("Error " + x + " at " + x.stack);
+      return null;
+    }
+  };
+};
+
+/**
+ * Fetch asynchronously the contents of a file using xpcom.
+ *
+ * Used for comparing xpcom-based results to os.file-based results.
+ *
+ * @param {string} path The _absolute_ path to the file.
+ * @return {promise}
+ * @resolves {string} The contents of the file.
+ */
+var reference_fetch_file = function reference_fetch_file(path, test) {
+  test.info("Fetching file " + path);
+  let promise = Promise.defer();
+  let file = new FileUtils.File(path);
+  NetUtil.asyncFetch({
+    uri: NetUtil.newURI(file),
+    loadUsingSystemPrincipal: true
+  }, function(stream, status) {
+      if (!Components.isSuccessCode(status)) {
+        promise.reject(status);
+        return;
+      }
+      let result, reject;
+      try {
+        result = NetUtil.readInputStreamToString(stream, stream.available());
+      } catch (x) {
+        reject = x;
+      }
+      stream.close();
+      if (reject) {
+        promise.reject(reject);
+      } else {
+        promise.resolve(result);
+      }
+    });
+
+  return promise.promise;
+};
+
+/**
+ * Compare asynchronously the contents two files using xpcom.
+ *
+ * Used for comparing xpcom-based results to os.file-based results.
+ *
+ * @param {string} a The _absolute_ path to the first file.
+ * @param {string} b The _absolute_ path to the second file.
+ *
+ * @resolves {null}
+ */
+var reference_compare_files = function reference_compare_files(a, b, test) {
+  test.info("Comparing files " + a + " and " + b);
+  let a_contents = yield reference_fetch_file(a, test);
+  let b_contents = yield reference_fetch_file(b, test);
+  is(a_contents, b_contents, "Contents of files " + a + " and " + b + " match");
+};
+
+var reference_dir_contents = function reference_dir_contents(path) {
+  let result = [];
+  let entries = new FileUtils.File(path).directoryEntries;
+  while (entries.hasMoreElements()) {
+    let entry = entries.getNext().QueryInterface(Components.interfaces.nsILocalFile);
+    result.push(entry.path);
+  }
+  return result;
+};
+
+// Set/Unset OS.Shared.DEBUG, OS.Shared.TEST and a console listener.
+function toggleDebugTest (pref, consoleListener) {
+  Services.prefs.setBoolPref("toolkit.osfile.log", pref);
+  Services.prefs.setBoolPref("toolkit.osfile.log.redirect", pref);
+  Services.console[pref ? "registerListener" : "unregisterListener"](
+    consoleListener);
+}
+
+var test = maketest("Main", function main(test) {
+  return Task.spawn(function() {
+    SimpleTest.waitForExplicitFinish();
+    yield test_stat();
+    yield test_debug();
+    yield test_info_features_detect();
+    yield test_position();
+    yield test_iter();
+    yield test_exists();
+    yield test_debug_test();
+    info("Test is over");
+    SimpleTest.finish();
+  });
+});
+
+/**
+ * A file that we know exists and that can be used for reading.
+ */
+var EXISTING_FILE = OS.Path.join("chrome", "toolkit", "components",
+  "osfile", "tests", "mochi", "main_test_osfile_async.js");
+
+/**
+ * Test OS.File.stat and OS.File.prototype.stat
+ */
+var test_stat = maketest("stat", function stat(test) {
+  return Task.spawn(function() {
+    // Open a file and stat it
+    let file = yield OS.File.open(EXISTING_FILE);
+    let stat1;
+
+    try {
+      test.info("Stating file");
+      stat1 = yield file.stat();
+      test.ok(true, "stat has worked " + stat1);
+      test.ok(stat1, "stat is not empty");
+    } finally {
+      yield file.close();
+    }
+
+    // Stat the same file without opening it
+    test.info("Stating a file without opening it");
+    let stat2 = yield OS.File.stat(EXISTING_FILE);
+    test.ok(true, "stat 2 has worked " + stat2);
+    test.ok(stat2, "stat 2 is not empty");
+    for (let key in stat2) {
+      test.is("" + stat1[key], "" + stat2[key], "Stat field " + key + "is the same");
+    }
+  });
+});
+
+/**
+ * Test feature detection using OS.File.Info.prototype on main thread
+ */
+var test_info_features_detect = maketest("features_detect", function features_detect(test) {
+  return Task.spawn(function() {
+    if (OS.Constants.Win) {
+      // see if winBirthDate is defined
+      if ("winBirthDate" in OS.File.Info.prototype) {
+        test.ok(true, "winBirthDate is defined");
+      } else {
+        test.fail("winBirthDate not defined though we are under Windows");
+      }
+    } else if (OS.Constants.libc) {
+      // see if unixGroup is defined
+      if ("unixGroup" in OS.File.Info.prototype) {
+        test.ok(true, "unixGroup is defined");
+      } else {
+        test.fail("unixGroup is not defined though we are under Unix");
+      }
+    }
+  });
+});
+
+/**
+ * Test file.{getPosition, setPosition}
+ */
+var test_position = maketest("position", function position(test) {
+  return Task.spawn(function() {
+    let file = yield OS.File.open(EXISTING_FILE);
+
+    try {
+      let view = yield file.read();
+      test.info("First batch of content read");
+      let CHUNK_SIZE = 178;// An arbitrary number of bytes to read from the file
+      let pos = yield file.getPosition();
+      test.info("Obtained position");
+      test.is(pos, view.byteLength, "getPosition returned the end of the file");
+      pos = yield file.setPosition(-CHUNK_SIZE, OS.File.POS_END);
+      test.info("Changed position");
+      test.is(pos, view.byteLength - CHUNK_SIZE, "setPosition returned the correct position");
+
+      let view2 = yield file.read();
+      test.info("Read the end of the file");
+      for (let i = 0; i < CHUNK_SIZE; ++i) {
+        if (view2[i] != view[i + view.byteLength - CHUNK_SIZE]) {
+          test.is(view2[i], view[i], "setPosition put us in the right position");
+        }
+      }
+    } finally {
+      yield file.close();
+    }
+  });
+});
+
+/**
+ * Test OS.File.prototype.{DirectoryIterator}
+ */
+var test_iter = maketest("iter", function iter(test) {
+  return Task.spawn(function() {
+    let currentDir = yield OS.File.getCurrentDirectory();
+
+    // Trivial walks through the directory
+    test.info("Preparing iteration");
+    let iterator = new OS.File.DirectoryIterator(currentDir);
+    let temporary_file_name = OS.Path.join(currentDir, "empty-temporary-file.tmp");
+    try {
+      yield OS.File.remove(temporary_file_name);
+    } catch (err) {
+      // Ignore errors removing file
+    }
+    let allFiles1 = yield iterator.nextBatch();
+    test.info("Obtained all files through nextBatch");
+    test.isnot(allFiles1.length, 0, "There is at least one file");
+    test.isnot(allFiles1[0].path, null, "Files have a path");
+
+    // Ensure that we have the same entries with |reference_dir_contents|
+    let referenceEntries = new Set();
+    for (let entry of reference_dir_contents(currentDir)) {
+      referenceEntries.add(entry);
+    }
+    test.is(referenceEntries.size, allFiles1.length, "All the entries in the directory have been listed");
+    for (let entry of allFiles1) {
+      test.ok(referenceEntries.has(entry.path), "File " + entry.path + " effectively exists");
+      // Ensure that we have correct isDir and isSymLink
+      // Current directory is {objdir}/_tests/testing/mochitest/, assume it has some dirs and symlinks.
+      var f = new FileUtils.File(entry.path);
+      test.is(entry.isDir, f.isDirectory(), "Get file " + entry.path + " isDir correctly");
+      test.is(entry.isSymLink, f.isSymlink(), "Get file " + entry.path + " isSymLink correctly");
+    }
+
+    yield iterator.close();
+    test.info("Closed iterator");
+
+    test.info("Double closing DirectoryIterator");
+    iterator = new OS.File.DirectoryIterator(currentDir);
+    yield iterator.close();
+    yield iterator.close(); //double closing |DirectoryIterator|
+    test.ok(true, "|DirectoryIterator| was closed twice successfully");
+
+    let allFiles2 = [];
+    let i = 0;
+    iterator = new OS.File.DirectoryIterator(currentDir);
+    yield iterator.forEach(function(entry, index) {
+      test.is(i++, index, "Getting the correct index");
+      allFiles2.push(entry);
+    });
+    test.info("Obtained all files through forEach");
+    is(allFiles1.length, allFiles2.length, "Both runs returned the same number of files");
+    for (let i = 0; i < allFiles1.length; ++i) {
+      if (allFiles1[i].path != allFiles2[i].path) {
+        test.is(allFiles1[i].path, allFiles2[i].path, "Both runs return the same files");
+        break;
+      }
+    }
+
+    // Testing batch iteration + whether an iteration can be stopped early
+    let BATCH_LENGTH = 10;
+    test.info("Getting some files through nextBatch");
+    yield iterator.close();
+
+    iterator = new OS.File.DirectoryIterator(currentDir);
+    let someFiles1 = yield iterator.nextBatch(BATCH_LENGTH);
+    let someFiles2 = yield iterator.nextBatch(BATCH_LENGTH);
+    yield iterator.close();
+
+    iterator = new OS.File.DirectoryIterator(currentDir);
+    yield iterator.forEach(function cb(entry, index, iterator) {
+      if (index < BATCH_LENGTH) {
+        test.is(entry.path, someFiles1[index].path, "Both runs return the same files (part 1)");
+      } else if (index < 2*BATCH_LENGTH) {
+        test.is(entry.path, someFiles2[index - BATCH_LENGTH].path, "Both runs return the same files (part 2)");
+      } else if (index == 2 * BATCH_LENGTH) {
+        test.info("Attempting to stop asynchronous forEach");
+        return iterator.close();
+      } else {
+        test.fail("Can we stop an asynchronous forEach? " + index);
+      }
+      return null;
+    });
+    yield iterator.close();
+
+    // Ensuring that we find new files if they appear
+    let file = yield OS.File.open(temporary_file_name, { write: true } );
+    file.close();
+    iterator = new OS.File.DirectoryIterator(currentDir);
+    try {
+      let files = yield iterator.nextBatch();
+      is(files.length, allFiles1.length + 1, "The directory iterator has noticed the new file");
+      let exists = yield iterator.exists();
+      test.ok(exists, "After nextBatch, iterator detects that the directory exists");
+    } finally {
+      yield iterator.close();
+    }
+
+    // Ensuring that opening a non-existing directory fails consistently
+    // once iteration starts.
+    try {
+      iterator = null;
+      iterator = new OS.File.DirectoryIterator("/I do not exist");
+      let exists = yield iterator.exists();
+      test.ok(!exists, "Before any iteration, iterator detects that the directory doesn't exist");
+      let exn = null;
+      try {
+        yield iterator.next();
+      } catch (ex if ex instanceof OS.File.Error && ex.becauseNoSuchFile) {
+        exn = ex;
+        let exists = yield iterator.exists();
+        test.ok(!exists, "After one iteration, iterator detects that the directory doesn't exist");
+      }
+      test.ok(exn, "Iterating through a directory that does not exist has failed with becauseNoSuchFile");
+    } finally {
+      if (iterator) {
+        iterator.close();
+      }
+    }
+    test.ok(!!iterator, "The directory iterator for a non-existing directory was correctly created");
+  });
+});
+
+/**
+ * Test OS.File.prototype.{exists}
+ */
+var test_exists = maketest("exists", function exists(test) {
+  return Task.spawn(function() {
+    let fileExists = yield OS.File.exists(EXISTING_FILE);
+    test.ok(fileExists, "file exists");
+    fileExists = yield OS.File.exists(EXISTING_FILE + ".tmp");
+    test.ok(!fileExists, "file does not exists");
+  });
+});
+
+/**
+ * Test changes to OS.Shared.DEBUG flag.
+ */
+var test_debug = maketest("debug", function debug(test) {
+  return Task.spawn(function() {
+    function testSetDebugPref (pref) {
+      try {
+        Services.prefs.setBoolPref("toolkit.osfile.log", pref);
+      } catch (x) {
+        test.fail("Setting OS.Shared.DEBUG to " + pref +
+          " should not cause error.");
+      } finally {
+        test.is(OS.Shared.DEBUG, pref, "OS.Shared.DEBUG is set correctly.");
+      }
+    }
+    testSetDebugPref(true);
+    let workerDEBUG = yield OS.File.GET_DEBUG();
+    test.is(workerDEBUG, true, "Worker's DEBUG is set.");
+    testSetDebugPref(false);
+    workerDEBUG = yield OS.File.GET_DEBUG();
+    test.is(workerDEBUG, false, "Worker's DEBUG is unset.");
+  });
+});
+
+/**
+ * Test logging in the main thread with set OS.Shared.DEBUG and
+ * OS.Shared.TEST flags.
+ */
+var test_debug_test = maketest("debug_test", function debug_test(test) {
+  return Task.spawn(function () {
+    // Create a console listener.
+    let consoleListener = {
+      observe: function (aMessage) {
+        // Ignore unexpected messages.
+        if (!(aMessage instanceof Components.interfaces.nsIConsoleMessage)) {
+          return;
+        }
+        if (aMessage.message.indexOf("TEST OS") < 0) {
+          return;
+        }
+        test.ok(true, "DEBUG TEST messages are logged correctly.");
+      }
+    };
+    toggleDebugTest(true, consoleListener);
+    // Execution of OS.File.exist method will trigger OS.File.LOG several times.
+    let fileExists = yield OS.File.exists(EXISTING_FILE);
+    toggleDebugTest(false, consoleListener);
+  });
+});
+
+
diff --git a/toolkit/components/osfile/tests/mochi/test_osfile_async.xul b/toolkit/components/osfile/tests/mochi/test_osfile_async.xul
new file mode 100644
index 000000000..1ef103f02
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/test_osfile_async.xul
@@ -0,0 +1,23 @@
+<?xml version="1.0"?>
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<window title="Testing async I/O with OS.File"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        onload="test();">
+
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"/>
+  <script type="application/javascript"
+          src="main_test_osfile_async.js"/>
+
+  <body xmlns="http://www.w3.org/1999/xhtml">
+    <p id="display"></p>
+    <div id="content" style="display:none;"></div>
+    <pre id="test"></pre>
+  </body>
+  <label id="test-result"/>
+</window>
diff --git a/toolkit/components/osfile/tests/mochi/test_osfile_back.xul b/toolkit/components/osfile/tests/mochi/test_osfile_back.xul
new file mode 100644
index 000000000..b6af6303f
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/test_osfile_back.xul
@@ -0,0 +1,46 @@
+<?xml version="1.0"?>
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<window title="Testing OS.File on a chrome worker thread"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        onload="test();">
+
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"/>
+  <script type="application/javascript"
+          src="worker_handler.js"/>
+  <script type="application/javascript">
+  <![CDATA[
+
+let worker;
+
+function test() {
+  ok(true, "test_osfile.xul: Starting test");
+  if (navigator.platform.indexOf("Win") != -1) {
+    ok(true, "test_osfile.xul: Using Windows test suite");
+    worker = new ChromeWorker("worker_test_osfile_win.js");
+  } else {
+    ok(true, "test_osfile.xul: Using Unix test suite");
+    worker = new ChromeWorker("worker_test_osfile_unix.js");
+  }
+  SimpleTest.waitForExplicitFinish();
+  ok(true, "test_osfile.xul: Chrome worker created");
+  dump("MAIN: go\n");
+  worker_handler(worker);
+  worker.postMessage(0);
+  ok(true, "test_osfile.xul: Test in progress");
+};
+]]>
+  </script>
+
+  <body xmlns="http://www.w3.org/1999/xhtml">
+    <p id="display"></p>
+    <div id="content" style="display:none;"></div>
+    <pre id="test"></pre>
+  </body>
+  <label id="test-result"/>
+</window>
diff --git a/toolkit/components/osfile/tests/mochi/test_osfile_comms.xul b/toolkit/components/osfile/tests/mochi/test_osfile_comms.xul
new file mode 100644
index 000000000..88e474ce2
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/test_osfile_comms.xul
@@ -0,0 +1,84 @@
+<?xml version="1.0"?>
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<window title="Testing OS.File on a chrome worker thread"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        onload="test();">
+
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"/>
+  <script type="application/javascript">
+  <![CDATA[
+
+"use strict";
+
+let worker;
+
+let test = function test() {
+  SimpleTest.info("test_osfile_comms.xul: Starting test");
+  Components.utils.import("resource://gre/modules/ctypes.jsm");
+  Components.utils.import("resource://gre/modules/osfile.jsm");
+  worker = new ChromeWorker("worker_test_osfile_comms.js");
+  SimpleTest.waitForExplicitFinish();
+  try {
+    worker.onerror = function onerror(error) {
+      SimpleTest.ok(false, "received error "+error);
+    }
+   worker.onmessage = function onmessage(msg) {
+    Components.utils.forceShrinkingGC();
+    switch (msg.data.kind) {
+      case "is":
+        SimpleTest.ok(msg.data.outcome, msg.data.description +
+        " ("+ msg.data.a + " ==? " + msg.data.b + ")" );
+        return;
+      case "isnot":
+        SimpleTest.ok(msg.data.outcome, msg.data.description +
+        " ("+ msg.data.a + " !=? " + msg.data.b + ")" );
+        return;
+      case "ok":
+        SimpleTest.ok(msg.data.condition, msg.data.description);
+        return;
+      case "info":
+        SimpleTest.info(msg.data.description);
+        return;
+      case "finish":
+        SimpleTest.finish();
+        return;
+      case "value":
+        SimpleTest.ok(true, "test_osfile_comms.xul: Received value " + JSON.stringify(msg.data.value));
+        let type = eval(msg.data.typename);
+        let check = eval(msg.data.check);
+        let value = msg.data.value;
+        let deserialized = type.fromMsg(value);
+        check(deserialized, "Main thread test: ");
+       return;
+      default:
+        SimpleTest.ok(false, "test_osfile_comms.xul: wrong message "+JSON.stringify(msg.data));
+        return;
+      }
+    };
+    worker.postMessage(0)
+    ok(true, "Worker launched");
+  } catch(x) {
+    // As we have set |waitForExplicitFinish|, we add this fallback
+    // in case of uncaught error, to ensure that the test does not
+    // just freeze.
+    ok(false, "Caught exception " + x + " at " + x.stack);
+    SimpleTest.finish();
+  }
+};
+
+]]>
+  </script>
+
+  <body xmlns="http://www.w3.org/1999/xhtml">
+    <p id="display"></p>
+    <div id="content" style="display:none;"></div>
+    <pre id="test"></pre>
+  </body>
+  <label id="test-result"/>
+</window>
diff --git a/toolkit/components/osfile/tests/mochi/test_osfile_front.xul b/toolkit/components/osfile/tests/mochi/test_osfile_front.xul
new file mode 100644
index 000000000..10d3fbd01
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/test_osfile_front.xul
@@ -0,0 +1,44 @@
+<?xml version="1.0"?>
+<!--
+  Any copyright is dedicated to the Public Domain.
+  http://creativecommons.org/publicdomain/zero/1.0/
+-->
+<window title="Testing OS.File on a chrome worker thread"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        onload="test();">
+
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js"/>
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/EventUtils.js"/>
+  <script type="application/javascript"
+          src="worker_handler.js"/>
+  <script type="application/javascript">
+  <![CDATA[
+
+let worker;
+let main = this;
+
+function test() {
+  info("test_osfile_front.xul: Starting test");
+
+  // Test the OS.File worker
+
+  worker = new ChromeWorker("worker_test_osfile_front.js");
+  SimpleTest.waitForExplicitFinish();
+  info("test_osfile_front.xul: Chrome worker created");
+  dump("MAIN: go\n");
+  worker_handler(worker);
+  worker.postMessage(0);
+  ok(true, "test_osfile_front.xul: Test in progress");
+};
+]]>
+  </script>
+
+  <body xmlns="http://www.w3.org/1999/xhtml">
+    <p id="display"></p>
+    <div id="content" style="display:none;"></div>
+    <pre id="test"></pre>
+  </body>
+  <label id="test-result"/>
+</window>
diff --git a/toolkit/components/osfile/tests/mochi/worker_handler.js b/toolkit/components/osfile/tests/mochi/worker_handler.js
new file mode 100644
index 000000000..6c513e6ba
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/worker_handler.js
@@ -0,0 +1,34 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function worker_handler(worker) {
+  worker.onerror = function(error) {
+    error.preventDefault();
+    ok(false, "Worker error " + error.message);
+  }
+  worker.onmessage = function(msg) {
+    ok(true, "MAIN: onmessage " + JSON.stringify(msg.data));
+    switch (msg.data.kind) {
+    case "is":
+      SimpleTest.ok(msg.data.outcome, msg.data.description +
+         "( "+ msg.data.a + " ==? " + msg.data.b + ")" );
+      return;
+    case "isnot":
+      SimpleTest.ok(msg.data.outcome, msg.data.description +
+      "( "+ msg.data.a + " !=? " + msg.data.b + ")" );
+         return;
+    case "ok":
+      SimpleTest.ok(msg.data.condition, msg.data.description);
+      return;
+    case "info":
+      SimpleTest.info(msg.data.description);
+      return;
+    case "finish":
+      SimpleTest.finish();
+      return;
+    default:
+      SimpleTest.ok(false, "test_osfile.xul: wrong message " + JSON.stringify(msg.data));
+      return;
+    }
+  };
+}
diff --git a/toolkit/components/osfile/tests/mochi/worker_test_osfile_comms.js b/toolkit/components/osfile/tests/mochi/worker_test_osfile_comms.js
new file mode 100644
index 000000000..5e8bdd9ca
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/worker_test_osfile_comms.js
@@ -0,0 +1,145 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+importScripts('worker_test_osfile_shared.js');
+
+// The set of samples for communications test. Declare as a global
+// variable to prevent this from being garbage-collected too early.
+var samples;
+
+self.onmessage = function(msg) {
+  info("Initializing");
+  self.onmessage = function on_unexpected_message(msg) {
+    throw new Error("Unexpected message " + JSON.stringify(msg.data));
+  };
+  importScripts("resource://gre/modules/osfile.jsm");
+  info("Initialization complete");
+
+  samples = [
+    { typename: "OS.Shared.Type.char.in_ptr",
+      valuedescr: "String",
+      value: "This is a test",
+      type: OS.Shared.Type.char.in_ptr,
+      check: function check_string(candidate, prefix) {
+        is(candidate, "This is a test", prefix);
+      }},
+    { typename: "OS.Shared.Type.char.in_ptr",
+      valuedescr: "Typed array",
+      value: (function() {
+                let view = new Uint8Array(15);
+                for (let i = 0; i < 15; ++i) {
+                  view[i] = i;
+                }
+                return view;
+              })(),
+      type: OS.Shared.Type.char.in_ptr,
+      check: function check_ArrayBuffer(candidate, prefix) {
+        for (let i = 0; i < 15; ++i) {
+          is(candidate[i], i % 256, prefix + "Checking that the contents of the ArrayBuffer were preserved");
+        }
+      }},
+    { typename: "OS.Shared.Type.char.in_ptr",
+      valuedescr: "Pointer",
+      value: new OS.Shared.Type.char.in_ptr.implementation(1),
+      type: OS.Shared.Type.char.in_ptr,
+      check: function check_ptr(candidate, prefix) {
+        let address = ctypes.cast(candidate, ctypes.uintptr_t).value.toString();
+        is(address, "1", prefix + "Checking that the pointer address was preserved");
+      }},
+    { typename: "OS.Shared.Type.char.in_ptr",
+      valuedescr: "C array",
+      value: (function() {
+                let buf = new (ctypes.ArrayType(ctypes.uint8_t, 15))();
+                for (let i = 0; i < 15; ++i) {
+                  buf[i] = i % 256;
+                }
+                return buf;
+              })(),
+      type: OS.Shared.Type.char.in_ptr,
+      check: function check_array(candidate, prefix) {
+        let cast = ctypes.cast(candidate, ctypes.uint8_t.ptr);
+        for (let i = 0; i < 15; ++i) {
+          is(cast.contents, i % 256, prefix + "Checking that the contents of the C array were preserved, index " + i);
+          cast = cast.increment();
+        }
+      }
+    },
+    { typename: "OS.File.Error",
+      valuedescr: "OS Error",
+      type: OS.File.Error,
+      value: new OS.File.Error("foo", 1),
+      check: function check_error(candidate, prefix) {
+        ok(candidate instanceof OS.File.Error,
+          prefix + "Error is an OS.File.Error");
+        ok(candidate.unixErrno == 1 || candidate.winLastError == 1,
+           prefix + "Error code is correct");
+        try {
+          let string = candidate.toString();
+          info(prefix + ".toString() works " + string);
+        } catch (x) {
+          ok(false, prefix + ".toString() fails " + x);
+        }
+      }
+    }
+  ];
+  samples.forEach(function test(sample) {
+    let type = sample.type;
+    let value = sample.value;
+    let check = sample.check;
+    info("Testing handling of type " + sample.typename + " communicating " + sample.valuedescr);
+
+    // 1. Test serialization
+    let serialized;
+    let exn;
+    try {
+      serialized = type.toMsg(value);
+    } catch (ex) {
+      exn = ex;
+    }
+    is(exn, null, "Can I serialize the following value? " + value +
+      " aka " + JSON.stringify(value));
+    if (exn) {
+      return;
+    }
+
+    if ("data" in serialized) {
+      // Unwrap from `Meta`
+      serialized = serialized.data;
+    }
+
+    // 2. Test deserialization
+    let deserialized;
+    try {
+      deserialized = type.fromMsg(serialized);
+    } catch (ex) {
+      exn = ex;
+    }
+    is(exn, null, "Can I deserialize the following message? " + serialized
+     + " aka " + JSON.stringify(serialized));
+    if (exn) {
+      return;
+    }
+
+    // 3. Local test deserialized value
+    info("Running test on deserialized value " + deserialized +
+      " aka " + JSON.stringify(deserialized));
+    check(deserialized, "Local test: ");
+
+    // 4. Test sending serialized
+    info("Attempting to send message");
+    try {
+      self.postMessage({kind:"value",
+        typename: sample.typename,
+        value: serialized,
+        check: check.toSource()});
+    } catch (ex) {
+      exn = ex;
+    }
+    is(exn, null, "Can I send the following message? " + serialized
+     + " aka " + JSON.stringify(serialized));
+  });
+
+  finish();
+ };
diff --git a/toolkit/components/osfile/tests/mochi/worker_test_osfile_front.js b/toolkit/components/osfile/tests/mochi/worker_test_osfile_front.js
new file mode 100644
index 000000000..29e613510
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/worker_test_osfile_front.js
@@ -0,0 +1,566 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+importScripts('worker_test_osfile_shared.js');
+importScripts("resource://gre/modules/workers/require.js");
+
+var SharedAll = require("resource://gre/modules/osfile/osfile_shared_allthreads.jsm");
+SharedAll.Config.DEBUG = true;
+
+function should_throw(f) {
+  try {
+    f();
+  } catch (x) {
+    return x;
+  }
+  return null;
+}
+
+self.onmessage = function onmessage_start(msg) {
+  self.onmessage = function onmessage_ignored(msg) {
+    log("ignored message " + JSON.stringify(msg.data));
+  };
+  try {
+    test_init();
+    test_open_existing_file();
+    test_open_non_existing_file();
+    test_flush_open_file();
+    test_copy_existing_file();
+    test_position();
+    test_move_file();
+    test_iter_dir();
+    test_info();
+    test_path();
+    test_exists_file();
+    test_remove_file();
+  } catch (x) {
+    log("Catching error: " + x);
+    log("Stack: " + x.stack);
+    log("Source: " + x.toSource());
+    ok(false, x.toString() + "\n" + x.stack);
+  }
+  finish();
+};
+
+function test_init() {
+  info("Starting test_init");
+  importScripts("resource://gre/modules/osfile.jsm");
+}
+
+/**
+ * Test that we can open an existing file.
+ */
+function test_open_existing_file()
+{
+  info("Starting test_open_existing");
+  let file = OS.File.open("chrome/toolkit/components/osfile/tests/mochi/worker_test_osfile_unix.js");
+  file.close();
+}
+
+/**
+ * Test that opening a file that does not exist fails with the right error.
+ */
+function test_open_non_existing_file()
+{
+  info("Starting test_open_non_existing");
+  let exn;
+  try {
+    let file = OS.File.open("/I do not exist");
+  } catch (x) {
+    exn = x;
+    info("test_open_non_existing_file: Exception detail " + exn);
+  }
+  ok(!!exn, "test_open_non_existing_file: Exception was raised ");
+  ok(exn instanceof OS.File.Error, "test_open_non_existing_file: Exception was a OS.File.Error");
+  ok(exn.becauseNoSuchFile, "test_open_non_existing_file: Exception confirms that the file does not exist");
+}
+
+/**
+ * Test that to ensure that |foo.flush()| does not
+ * cause an error, where |foo| is an open file.
+ */
+function test_flush_open_file()
+{
+  info("Starting test_flush_open_file");
+  let tmp = "test_flush.tmp";
+  let file = OS.File.open(tmp, {create: true, write: true});
+  file.flush();
+  file.close();
+  OS.File.remove(tmp);
+}
+
+/**
+ * Utility function for comparing two files (or a prefix of two files).
+ *
+ * This function returns nothing but fails of both files (or prefixes)
+ * are not identical.
+ *
+ * @param {string} test The name of the test (used for logging).
+ * @param {string} sourcePath The name of the first file.
+ * @param {string} destPath The name of the second file.
+ * @param {number=} prefix If specified, only compare the |prefix|
+ * first bytes of |sourcePath| and |destPath|.
+ */
+function compare_files(test, sourcePath, destPath, prefix)
+{
+  info(test + ": Comparing " + sourcePath + " and " + destPath);
+  let source = OS.File.open(sourcePath);
+  let dest = OS.File.open(destPath);
+  info("Files are open");
+  let sourceResult, destResult;
+  try {
+    if (prefix != undefined) {
+      sourceResult = source.read(prefix);
+      destResult = dest.read(prefix);
+    } else {
+      sourceResult = source.read();
+      destResult = dest.read();
+    }
+    is(sourceResult.length, destResult.length, test + ": Both files have the same size");
+    for (let i = 0; i < sourceResult.length; ++i) {
+      if (sourceResult[i] != destResult[i]) {
+        is(sourceResult[i] != destResult[i], test + ": Comparing char " + i);
+        break;
+      }
+    }
+  } finally {
+    source.close();
+    dest.close();
+  }
+  info(test + ": Comparison complete");
+}
+
+/**
+ * Test that copying a file using |copy| works.
+ */
+function test_copy_existing_file()
+{
+  let src_file_name =
+    OS.Path.join("chrome", "toolkit", "components", "osfile", "tests", "mochi",
+                 "worker_test_osfile_front.js");
+  let tmp_file_name = "test_osfile_front.tmp";
+  info("Starting test_copy_existing");
+  OS.File.copy(src_file_name, tmp_file_name);
+
+  info("test_copy_existing: Copy complete");
+  compare_files("test_copy_existing", src_file_name, tmp_file_name);
+
+  // Create a bogus file with arbitrary content, then attempt to overwrite
+  // it with |copy|.
+  let dest = OS.File.open(tmp_file_name, {trunc: true});
+  let buf = new Uint8Array(50);
+  dest.write(buf);
+  dest.close();
+
+  OS.File.copy(src_file_name, tmp_file_name);
+
+  compare_files("test_copy_existing 2", src_file_name, tmp_file_name);
+
+  // Attempt to overwrite with noOverwrite
+  let exn;
+  try {
+    OS.File.copy(src_file_name, tmp_file_name, {noOverwrite: true});
+  } catch(x) {
+    exn = x;
+  }
+  ok(!!exn, "test_copy_existing: noOverwrite prevents overwriting existing files");
+
+  info("test_copy_existing: Cleaning up");
+  OS.File.remove(tmp_file_name);
+}
+
+/**
+ * Test that moving a file works.
+ */
+function test_move_file()
+{
+  info("test_move_file: Starting");
+  // 1. Copy file into a temporary file
+  let src_file_name =
+    OS.Path.join("chrome", "toolkit", "components", "osfile", "tests", "mochi",
+                 "worker_test_osfile_front.js");
+  let tmp_file_name = "test_osfile_front.tmp";
+  let tmp2_file_name = "test_osfile_front.tmp2";
+  OS.File.copy(src_file_name, tmp_file_name);
+
+  info("test_move_file: Copy complete");
+
+  // 2. Move
+  OS.File.move(tmp_file_name, tmp2_file_name);
+
+  info("test_move_file: Move complete");
+
+  // 3. Check that destination exists
+  compare_files("test_move_file", src_file_name, tmp2_file_name);
+
+  // 4. Check that original file does not exist anymore
+  let exn;
+  try {
+    OS.File.open(tmp_file_name);
+  } catch (x) {
+    exn = x;
+  }
+  ok(!!exn, "test_move_file: Original file has been removed");
+
+  info("test_move_file: Cleaning up");
+  OS.File.remove(tmp2_file_name);
+}
+
+function test_iter_dir()
+{
+  info("test_iter_dir: Starting");
+
+  // Create a file, to be sure that it exists
+  let tmp_file_name = "test_osfile_front.tmp";
+  let tmp_file = OS.File.open(tmp_file_name, {write: true, trunc:true});
+  tmp_file.close();
+
+  let parent = OS.File.getCurrentDirectory();
+  info("test_iter_dir: directory " + parent);
+  let iterator = new OS.File.DirectoryIterator(parent);
+  info("test_iter_dir: iterator created");
+  let encountered_tmp_file = false;
+  for (let entry in iterator) {
+    // Checking that |name| can be decoded properly
+    info("test_iter_dir: encountering entry " + entry.name);
+
+    if (entry.name == tmp_file_name) {
+      encountered_tmp_file = true;
+      isnot(entry.isDir, "test_iter_dir: The temporary file is not a directory");
+      isnot(entry.isSymLink, "test_iter_dir: The temporary file is not a link");
+    }
+
+    let file;
+    let success = true;
+    try {
+      file = OS.File.open(entry.path);
+    } catch (x) {
+      if (x.becauseNoSuchFile) {
+        success = false;
+      }
+    }
+    if (file) {
+      file.close();
+    }
+    ok(success, "test_iter_dir: Entry " + entry.path + " exists");
+
+    if (OS.Win) {
+      // We assume that the files are at least as recent as 2009.
+      // Since this test was written in 2011 and some of our packaging
+      // sets dates arbitrarily to 2010, this should be safe.
+      let year = new Date().getFullYear();
+      let creation = entry.winCreationDate;
+      ok(creation, "test_iter_dir: Windows creation date exists: " + creation);
+      ok(creation.getFullYear() >= 2009 && creation.getFullYear() <= year, "test_iter_dir: consistent creation date");
+
+      let lastWrite = entry.winLastWriteDate;
+      ok(lastWrite, "test_iter_dir: Windows lastWrite date exists: " + lastWrite);
+      ok(lastWrite.getFullYear() >= 2009 && lastWrite.getFullYear() <= year, "test_iter_dir: consistent lastWrite date");
+
+      let lastAccess = entry.winLastAccessDate;
+      ok(lastAccess, "test_iter_dir: Windows lastAccess date exists: " + lastAccess);
+      ok(lastAccess.getFullYear() >= 2009 && lastAccess.getFullYear() <= year, "test_iter_dir: consistent lastAccess date");
+    }
+
+  }
+  ok(encountered_tmp_file, "test_iter_dir: We have found the temporary file");
+
+  info("test_iter_dir: Cleaning up");
+  iterator.close();
+
+  // Testing nextBatch()
+  iterator = new OS.File.DirectoryIterator(parent);
+  let allentries = [];
+  for (let x in iterator) {
+    allentries.push(x);
+  }
+  iterator.close();
+
+  ok(allentries.length >= 14, "test_iter_dir: Meta-check: the test directory should contain at least 14 items");
+
+  iterator = new OS.File.DirectoryIterator(parent);
+  let firstten = iterator.nextBatch(10);
+  is(firstten.length, 10, "test_iter_dir: nextBatch(10) returns 10 items");
+  for (let i = 0; i < firstten.length; ++i) {
+    is(allentries[i].path, firstten[i].path, "test_iter_dir: Checking that batch returns the correct entries");
+  }
+  let nextthree = iterator.nextBatch(3);
+  is(nextthree.length, 3, "test_iter_dir: nextBatch(3) returns 3 items");
+  for (let i = 0; i < nextthree.length; ++i) {
+    is(allentries[i + firstten.length].path, nextthree[i].path, "test_iter_dir: Checking that batch 2 returns the correct entries");
+  }
+  let everythingelse = iterator.nextBatch();
+  ok(everythingelse.length >= 1, "test_iter_dir: nextBatch() returns at least one item");
+  for (let i = 0; i < everythingelse.length; ++i) {
+    is(allentries[i + firstten.length + nextthree.length].path, everythingelse[i].path, "test_iter_dir: Checking that batch 3 returns the correct entries");
+  }
+  is(iterator.nextBatch().length, 0, "test_iter_dir: Once there is nothing left, nextBatch returns an empty array");
+  iterator.close();
+
+  iterator = new OS.File.DirectoryIterator(parent);
+  iterator.close();
+  is(iterator.nextBatch().length, 0, "test_iter_dir: nextBatch on closed iterator returns an empty array");
+
+  iterator = new OS.File.DirectoryIterator(parent);
+  let allentries2 = iterator.nextBatch();
+  is(allentries.length, allentries2.length, "test_iter_dir: Checking that getBatch(null) returns the right number of entries");
+  for (let i = 0; i < allentries.length; ++i) {
+    is(allentries[i].path, allentries2[i].path, "test_iter_dir: Checking that getBatch(null) returns everything in the right order");
+  }
+  iterator.close();
+
+  // Test forEach
+  iterator = new OS.File.DirectoryIterator(parent);
+  let index = 0;
+  iterator.forEach(
+    function cb(entry, aIndex, aIterator) {
+      is(index, aIndex, "test_iter_dir: Checking that forEach index is correct");
+      ok(iterator == aIterator, "test_iter_dir: Checking that right iterator is passed");
+      if (index < 10) {
+        is(allentries[index].path, entry.path, "test_iter_dir: Checking that forEach entry is correct");
+      } else if (index == 10) {
+        iterator.close();
+      } else {
+        ok(false, "test_iter_dir: Checking that forEach can be stopped early");
+      }
+      ++index;
+  });
+  iterator.close();
+
+  //test for prototype |OS.File.DirectoryIterator.unixAsFile|
+  if ("unixAsFile" in OS.File.DirectoryIterator.prototype) {
+    info("testing property unixAsFile");
+    let path = OS.Path.join("chrome", "toolkit", "components", "osfile", "tests", "mochi");
+    iterator = new OS.File.DirectoryIterator(path);
+
+    let dir_file = iterator.unixAsFile();// return |File|
+    let stat0 = dir_file.stat();
+    let stat1 = OS.File.stat(path);
+
+    let unix_info_to_string = function unix_info_to_string(info) {
+      return "| " + info.unixMode + " | " + info.unixOwner + " | " + info.unixGroup + " | " + info.creationDate + " | " + info.lastModificationDate + " | " + info.lastAccessDate + " | " + info.size + " |";
+    };
+
+    let s0_string = unix_info_to_string(stat0);
+    let s1_string = unix_info_to_string(stat1);
+
+    ok(stat0.isDir, "unixAsFile returned a directory");
+    is(s0_string, s1_string, "unixAsFile returned the correct file");
+    dir_file.close();
+    iterator.close();
+  }
+  info("test_iter_dir: Complete");
+}
+
+function test_position() {
+  info("test_position: Starting");
+
+  ok("POS_START" in OS.File, "test_position: POS_START exists");
+  ok("POS_CURRENT" in OS.File, "test_position: POS_CURRENT exists");
+  ok("POS_END" in OS.File, "test_position: POS_END exists");
+
+  let ARBITRARY_POSITION = 321;
+  let src_file_name =
+    OS.Path.join("chrome", "toolkit", "components", "osfile", "tests", "mochi",
+                 "worker_test_osfile_front.js");
+
+  let file = OS.File.open(src_file_name);
+  is(file.getPosition(), 0, "test_position: Initial position is 0");
+
+  let size = 0 + file.stat().size; // Hack: We can remove this 0 + once 776259 has landed
+
+  file.setPosition(ARBITRARY_POSITION, OS.File.POS_START);
+  is(file.getPosition(), ARBITRARY_POSITION, "test_position: Setting position from start");
+
+  file.setPosition(0, OS.File.POS_START);
+  is(file.getPosition(), 0, "test_position: Setting position from start back to 0");
+
+  file.setPosition(ARBITRARY_POSITION);
+  is(file.getPosition(), ARBITRARY_POSITION, "test_position: Setting position without argument");
+
+  file.setPosition(-ARBITRARY_POSITION, OS.File.POS_END);
+  is(file.getPosition(), size - ARBITRARY_POSITION, "test_position: Setting position from end");
+
+  file.setPosition(ARBITRARY_POSITION, OS.File.POS_CURRENT);
+  is(file.getPosition(), size, "test_position: Setting position from current");
+
+  file.close();
+  info("test_position: Complete");
+}
+
+function test_info() {
+  info("test_info: Starting");
+
+  let filename = "test_info.tmp";
+  let size = 261;// An arbitrary file length
+  let start = new Date();
+
+ // Cleanup any leftover from previous tests
+  try {
+    OS.File.remove(filename);
+    info("test_info: Cleaned up previous garbage");
+  } catch (x) {
+    if (!x.becauseNoSuchFile) {
+      throw x;
+    }
+    info("test_info: No previous garbage");
+  }
+
+  let file = OS.File.open(filename, {trunc: true});
+  let buf = new ArrayBuffer(size);
+  file._write(buf, size);
+  file.close();
+
+  // Test OS.File.stat on new file
+  let stat = OS.File.stat(filename);
+  ok(!!stat, "test_info: info acquired");
+  ok(!stat.isDir, "test_info: file is not a directory");
+  is(stat.isSymLink, false, "test_info: file is not a link");
+  is(stat.size.toString(), size, "test_info: correct size");
+
+  let stop = new Date();
+
+  // We round down/up by 1s as file system precision is lower than
+  // Date precision (no clear specifications about that, but it seems
+  // that this can be a little over 1 second under ext3 and 2 seconds
+  // under FAT).
+  let SLOPPY_FILE_SYSTEM_ADJUSTMENT = 3000;
+  let startMs = start.getTime() - SLOPPY_FILE_SYSTEM_ADJUSTMENT;
+  let stopMs  = stop.getTime() + SLOPPY_FILE_SYSTEM_ADJUSTMENT;
+  info("Testing stat with bounds [ " + startMs + ", " + stopMs +" ]");
+
+  (function() {
+    let birth;
+    if ("winBirthDate" in stat) {
+      birth = stat.winBirthDate;
+    } else if ("macBirthDate" in stat) {
+      birth = stat.macBirthDate;
+    } else {
+      ok(true, "Skipping birthdate test");
+      return;
+    }
+    ok(birth.getTime() <= stopMs,
+    "test_info: platformBirthDate is consistent");
+    // Note: Previous versions of this test checked whether the file
+    // has been created after the start of the test. Unfortunately,
+    // this sometimes failed under Windows, in specific circumstances:
+    // if the file has been removed at the start of the test and
+    // recreated immediately, the Windows file system detects this and
+    // decides that the file was actually truncated rather than
+    // recreated, hence that it should keep its previous creation
+    // date.  Debugging hilarity ensues.
+  });
+
+  let change = stat.lastModificationDate;
+  info("Testing lastModificationDate: " + change);
+  ok(change.getTime() >= startMs && change.getTime() <= stopMs,
+     "test_info: lastModificationDate is consistent");
+
+  // Test OS.File.prototype.stat on new file
+  file = OS.File.open(filename);
+  try {
+    stat = file.stat();
+  } finally {
+    file.close();
+  }
+
+  ok(!!stat, "test_info: info acquired 2");
+  ok(!stat.isDir, "test_info: file is not a directory 2");
+  ok(!stat.isSymLink, "test_info: file is not a link 2");
+  is(stat.size.toString(), size, "test_info: correct size 2");
+
+  stop = new Date();
+
+  // Round up/down as above
+  startMs = start.getTime() - SLOPPY_FILE_SYSTEM_ADJUSTMENT;
+  stopMs  = stop.getTime() + SLOPPY_FILE_SYSTEM_ADJUSTMENT;
+  info("Testing stat 2 with bounds [ " + startMs + ", " + stopMs +" ]");
+
+  let access = stat.lastAccessDate;
+  info("Testing lastAccessDate: " + access);
+  ok(access.getTime() >= startMs && access.getTime() <= stopMs,
+     "test_info: lastAccessDate is consistent");
+
+  change = stat.lastModificationDate;
+  info("Testing lastModificationDate 2: " + change);
+  ok(change.getTime() >= startMs && change.getTime() <= stopMs,
+     "test_info: lastModificationDate 2 is consistent");
+
+  // Test OS.File.stat on directory
+  stat = OS.File.stat(OS.File.getCurrentDirectory());
+  ok(!!stat, "test_info: info on directory acquired");
+  ok(stat.isDir, "test_info: directory is a directory");
+
+  info("test_info: Complete");
+}
+
+// Note that most of the features of path are tested in
+// worker_test_osfile_{unix, win}.js
+function test_path()
+{
+  info("test_path: starting");
+  let abcd = OS.Path.join("a", "b", "c", "d");
+  is(OS.Path.basename(abcd), "d", "basename of a/b/c/d");
+
+  let abc = OS.Path.join("a", "b", "c");
+  is(OS.Path.dirname(abcd), abc, "dirname of a/b/c/d");
+
+  let abdotsc = OS.Path.join("a", "b", "..", "c");
+  is(OS.Path.normalize(abdotsc), OS.Path.join("a", "c"), "normalize a/b/../c");
+
+  let adotsdotsdots = OS.Path.join("a", "..", "..", "..");
+  is(OS.Path.normalize(adotsdotsdots), OS.Path.join("..", ".."), "normalize a/../../..");
+
+  info("test_path: Complete");
+}
+
+/**
+ * Test the file |exists| method.
+ */
+function test_exists_file()
+{
+  let file_name = OS.Path.join("chrome", "toolkit", "components" ,"osfile",
+                               "tests", "mochi", "test_osfile_front.xul");
+  info("test_exists_file: starting");
+  ok(OS.File.exists(file_name), "test_exists_file: file exists (OS.File.exists)");
+  ok(!OS.File.exists(file_name + ".tmp"), "test_exists_file: file does not exists (OS.File.exists)");
+
+  let dir_name = OS.Path.join("chrome", "toolkit", "components" ,"osfile",
+                               "tests", "mochi");
+  ok(OS.File.exists(dir_name), "test_exists_file: directory exists");
+  ok(!OS.File.exists(dir_name) + ".tmp", "test_exists_file: directory does not exist");
+
+  info("test_exists_file: complete");
+}
+
+/**
+ * Test the file |remove| method.
+ */
+function test_remove_file()
+{
+  let absent_file_name = "test_osfile_front_absent.tmp";
+
+  // Check that removing absent files is handled correctly
+  let exn = should_throw(function() {
+    OS.File.remove(absent_file_name, {ignoreAbsent: false});
+  });
+  ok(!!exn, "test_remove_file: throws if there is no such file");
+
+  exn = should_throw(function() {
+    OS.File.remove(absent_file_name, {ignoreAbsent: true});
+    OS.File.remove(absent_file_name);
+  });
+  ok(!exn, "test_remove_file: ignoreAbsent works");
+
+  if (OS.Win) {
+    let file_name = "test_osfile_front_file_to_remove.tmp";
+    let file = OS.File.open(file_name, {write: true});
+    file.close();
+    ok(OS.File.exists(file_name), "test_remove_file: test file exists");
+    OS.Win.File.SetFileAttributes(file_name,
+                                  OS.Constants.Win.FILE_ATTRIBUTE_READONLY);
+    OS.File.remove(file_name);
+    ok(!OS.File.exists(file_name),
+       "test_remove_file: test file has been removed");
+  }
+}
diff --git a/toolkit/components/osfile/tests/mochi/worker_test_osfile_shared.js b/toolkit/components/osfile/tests/mochi/worker_test_osfile_shared.js
new file mode 100644
index 000000000..da82d4b0a
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/worker_test_osfile_shared.js
@@ -0,0 +1,32 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function log(text) {
+  dump("WORKER " + text + "\n");
+}
+
+function send(message) {
+  self.postMessage(message);
+}
+
+function finish() {
+  send({kind: "finish"});
+}
+
+function ok(condition, description) {
+  send({kind: "ok", condition: !!condition, description: "" + description});
+}
+
+function is(a, b, description) {
+  let outcome = a == b; // Need to decide outcome here, as not everything can be serialized
+  send({kind: "is", outcome: outcome, description: "" + description, a: "" + a, b: "" + b});
+}
+
+function isnot(a, b, description) {
+  let outcome = a != b; // Need to decide outcome here, as not everything can be serialized
+  send({kind: "isnot", outcome: outcome, description: "" + description, a: "" + a, b: "" + b});
+}
+
+function info(description) {
+  send({kind: "info", description: "" + description});
+}
diff --git a/toolkit/components/osfile/tests/mochi/worker_test_osfile_unix.js b/toolkit/components/osfile/tests/mochi/worker_test_osfile_unix.js
new file mode 100644
index 000000000..9fe2d0b4e
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/worker_test_osfile_unix.js
@@ -0,0 +1,201 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+importScripts('worker_test_osfile_shared.js');
+
+self.onmessage = function(msg) {
+  log("received message "+JSON.stringify(msg.data));
+  self.onmessage = function(msg) {
+    log("ignored message "+JSON.stringify(msg.data));
+  };
+  test_init();
+  test_getcwd();
+  test_open_close();
+  test_create_file();
+  test_access();
+  test_read_write();
+  test_passing_undefined();
+  finish();
+};
+
+function test_init() {
+  info("Starting test_init");
+  importScripts("resource://gre/modules/osfile.jsm");
+}
+
+function test_open_close() {
+  info("Starting test_open_close");
+  is(typeof OS.Unix.File.open, "function", "OS.Unix.File.open is a function");
+  let file = OS.Unix.File.open("chrome/toolkit/components/osfile/tests/mochi/worker_test_osfile_unix.js", OS.Constants.libc.O_RDONLY, 0);
+  isnot(file, -1, "test_open_close: opening succeeded");
+  info("Close: "+OS.Unix.File.close.toSource());
+  let result = OS.Unix.File.close(file);
+  is(result, 0, "test_open_close: close succeeded");
+
+  file = OS.Unix.File.open("/i do not exist", OS.Constants.libc.O_RDONLY, 0);
+  is(file, -1, "test_open_close: opening of non-existing file failed");
+  is(ctypes.errno, OS.Constants.libc.ENOENT, "test_open_close: error is ENOENT");
+}
+
+function test_create_file()
+{
+  info("Starting test_create_file");
+  let file = OS.Unix.File.open("test.tmp", OS.Constants.libc.O_RDWR
+                               | OS.Constants.libc.O_CREAT
+                               | OS.Constants.libc.O_TRUNC,
+                               OS.Constants.libc.S_IRWXU);
+  isnot(file, -1, "test_create_file: file created");
+  OS.Unix.File.close(file);
+}
+
+function test_access()
+{
+  info("Starting test_access");
+  let file = OS.Unix.File.open("test1.tmp", OS.Constants.libc.O_RDWR
+                               | OS.Constants.libc.O_CREAT
+                               | OS.Constants.libc.O_TRUNC,
+                               OS.Constants.libc.S_IRWXU);
+  let result = OS.Unix.File.access("test1.tmp", OS.Constants.libc.R_OK | OS.Constants.libc.W_OK | OS.Constants.libc.X_OK | OS.Constants.libc.F_OK);
+  is(result, 0, "first call to access() succeeded");
+  OS.Unix.File.close(file);
+
+  file = OS.Unix.File.open("test1.tmp", OS.Constants.libc.O_WRONLY
+                               | OS.Constants.libc.O_CREAT
+                               | OS.Constants.libc.O_TRUNC,
+                               OS.Constants.libc.S_IWUSR);
+
+  info("test_access: preparing second call to access()");
+  result = OS.Unix.File.access("test2.tmp", OS.Constants.libc.R_OK
+                        | OS.Constants.libc.W_OK
+                        | OS.Constants.libc.X_OK
+                        | OS.Constants.libc.F_OK);
+  is(result, -1, "test_access: second call to access() failed as expected");
+  is(ctypes.errno, OS.Constants.libc.ENOENT, "This is the correct error");
+  OS.Unix.File.close(file);
+}
+
+function test_getcwd()
+{
+  let array = new (ctypes.ArrayType(ctypes.char, 32768))();
+  let path = OS.Unix.File.getcwd(array, array.length);
+  if (ctypes.char.ptr(path).isNull()) {
+    ok(false, "test_get_cwd: getcwd returned null, errno: " + ctypes.errno);
+  }
+  let path2;
+  if (OS.Unix.File.get_current_dir_name) {
+    path2 = OS.Unix.File.get_current_dir_name();
+  } else {
+    path2 = OS.Unix.File.getwd_auto(null);
+  }
+  if (ctypes.char.ptr(path2).isNull()) {
+    ok(false, "test_get_cwd: getwd_auto/get_current_dir_name returned null, errno: " + ctypes.errno);
+  }
+  is(path.readString(), path2.readString(), "test_get_cwd: getcwd and getwd return the same path");
+}
+
+function test_read_write()
+{
+  let output_name = "osfile_copy.tmp";
+  // Copy file
+  let input = OS.Unix.File.open(
+    "chrome/toolkit/components/osfile/tests/mochi/worker_test_osfile_unix.js",
+    OS.Constants.libc.O_RDONLY, 0);
+  isnot(input, -1, "test_read_write: input file opened");
+  let output = OS.Unix.File.open("osfile_copy.tmp", OS.Constants.libc.O_RDWR
+    | OS.Constants.libc.O_CREAT
+    | OS.Constants.libc.O_TRUNC,
+    OS.Constants.libc.S_IRWXU);
+  isnot(output, -1, "test_read_write: output file opened");
+
+  let array = new (ctypes.ArrayType(ctypes.char, 4096))();
+  let bytes = -1;
+  let total = 0;
+  while (true) {
+    bytes = OS.Unix.File.read(input, array, 4096);
+    ok(bytes != undefined, "test_read_write: bytes is defined");
+    isnot(bytes, -1, "test_read_write: no read error");
+    let write_from = 0;
+    if (bytes == 0) {
+      break;
+    }
+    while (bytes > 0) {
+      let ptr = array.addressOfElement(write_from);
+      // Note: |write| launches an exception in case of error
+      let written = OS.Unix.File.write(output, array, bytes);
+      isnot(written, -1, "test_read_write: no write error");
+      write_from += written;
+      bytes -= written;
+    }
+    total += write_from;
+  }
+  info("test_read_write: copy complete " + total);
+
+  // Compare files
+  let result;
+  info("SEEK_SET: " + OS.Constants.libc.SEEK_SET);
+  info("Input: " + input + "(" + input.toSource() + ")");
+  info("Output: " + output + "(" + output.toSource() + ")");
+  result = OS.Unix.File.lseek(input, 0, OS.Constants.libc.SEEK_SET);
+  info("Result of lseek: " + result);
+  isnot(result, -1, "test_read_write: input seek succeeded " + ctypes.errno);
+  result = OS.Unix.File.lseek(output, 0, OS.Constants.libc.SEEK_SET);
+  isnot(result, -1, "test_read_write: output seek succeeded " + ctypes.errno);
+
+  let array2 = new (ctypes.ArrayType(ctypes.char, 4096))();
+  let bytes2 = -1;
+  let pos = 0;
+  while (true) {
+    bytes = OS.Unix.File.read(input, array, 4096);
+    isnot(bytes, -1, "test_read_write: input read succeeded");
+    bytes2 = OS.Unix.File.read(output, array2, 4096);
+    isnot(bytes, -1, "test_read_write: output read succeeded");
+    is(bytes > 0, bytes2 > 0, "Both files contain data or neither does "+bytes+", "+bytes2);
+    if (bytes == 0) {
+      break;
+    }
+    if (bytes != bytes2) {
+      // This would be surprising, but theoretically possible with a
+      // remote file system, I believe.
+      bytes = Math.min(bytes, bytes2);
+      pos += bytes;
+      result = OS.Unix.File.lseek(input, pos, OS.Constants.libc.SEEK_SET);
+      isnot(result, -1, "test_read_write: input seek succeeded");
+      result = OS.Unix.File.lseek(output, pos, OS.Constants.libc.SEEK_SET);
+      isnot(result, -1, "test_read_write: output seek succeeded");
+    } else {
+      pos += bytes;
+    }
+    for (let i = 0; i < bytes; ++i) {
+      if (array[i] != array2[i]) {
+        ok(false, "Files do not match at position " + i
+           + " ("+array[i] + "/"+array2[i] + ")");
+      }
+    }
+  }
+  info("test_read_write test complete");
+  result = OS.Unix.File.close(input);
+  isnot(result, -1, "test_read_write: input close succeeded");
+  result = OS.Unix.File.close(output);
+  isnot(result, -1, "test_read_write: output close succeeded");
+  result = OS.Unix.File.unlink(output_name);
+  isnot(result, -1, "test_read_write: input remove succeeded");
+  info("test_read_write cleanup complete");
+}
+
+function test_passing_undefined()
+{
+  info("Testing that an exception gets thrown when an FFI function is passed undefined");
+  let exceptionRaised = false;
+
+  try {
+    let file = OS.Unix.File.open(undefined, OS.Constants.libc.O_RDWR
+                                            | OS.Constants.libc.O_CREAT
+                                            | OS.Constants.libc.O_TRUNC,
+                                            OS.Constants.libc.S_IRWXU);
+  } catch(e if e instanceof TypeError && e.message.indexOf("open") > -1) {
+    exceptionRaised = true;
+  }
+
+  ok(exceptionRaised, "test_passing_undefined: exception gets thrown")
+}
+
diff --git a/toolkit/components/osfile/tests/mochi/worker_test_osfile_win.js b/toolkit/components/osfile/tests/mochi/worker_test_osfile_win.js
new file mode 100644
index 000000000..f41fdecfe
--- /dev/null
+++ b/toolkit/components/osfile/tests/mochi/worker_test_osfile_win.js
@@ -0,0 +1,211 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+importScripts('worker_test_osfile_shared.js');
+
+self.onmessage = function(msg) {
+  self.onmessage = function(msg) {
+    log("ignored message "+JSON.stringify(msg.data));
+  };
+
+  test_init();
+  test_GetCurrentDirectory();
+  test_OpenClose();
+  test_CreateFile();
+  test_ReadWrite();
+  test_passing_undefined();
+  finish();
+};
+
+function test_init() {
+  info("Starting test_init");
+  importScripts("resource://gre/modules/osfile.jsm");
+}
+
+function test_OpenClose() {
+  info("Starting test_OpenClose");
+  is(typeof OS.Win.File.CreateFile, "function", "OS.Win.File.CreateFile is a function");
+  is(OS.Win.File.CloseHandle(OS.Constants.Win.INVALID_HANDLE_VALUE), true, "CloseHandle returns true given the invalid handle");
+  is(OS.Win.File.FindClose(OS.Constants.Win.INVALID_HANDLE_VALUE), true, "FindClose returns true given the invalid handle");
+  isnot(OS.Constants.Win.GENERIC_READ, undefined, "GENERIC_READ exists");
+  isnot(OS.Constants.Win.FILE_SHARE_READ, undefined, "FILE_SHARE_READ exists");
+  isnot(OS.Constants.Win.FILE_ATTRIBUTE_NORMAL, undefined, "FILE_ATTRIBUTE_NORMAL exists");
+  let file = OS.Win.File.CreateFile(
+    "chrome\\toolkit\\components\\osfile\\tests\\mochi\\worker_test_osfile_win.js",
+    OS.Constants.Win.GENERIC_READ,
+    0,
+    null,
+    OS.Constants.Win.OPEN_EXISTING,
+    0,
+    null);
+  info("test_OpenClose: Passed open");
+  isnot(file, OS.Constants.Win.INVALID_HANDLE_VALUE, "test_OpenClose: file opened");
+  let result = OS.Win.File.CloseHandle(file);
+  isnot(result, 0, "test_OpenClose: close succeeded");
+
+  file = OS.Win.File.CreateFile(
+    "\\I do not exist",
+    OS.Constants.Win.GENERIC_READ,
+    OS.Constants.Win.FILE_SHARE_READ,
+    null,
+    OS.Constants.Win.OPEN_EXISTING,
+    OS.Constants.Win.FILE_ATTRIBUTE_NORMAL,
+    null);
+  is(file, OS.Constants.Win.INVALID_HANDLE_VALUE, "test_OpenClose: cannot open non-existing file");
+  is(ctypes.winLastError, OS.Constants.Win.ERROR_FILE_NOT_FOUND, "test_OpenClose: error is ERROR_FILE_NOT_FOUND");
+}
+
+function test_CreateFile()
+{
+  info("Starting test_CreateFile");
+  let file = OS.Win.File.CreateFile(
+    "test.tmp",
+    OS.Constants.Win.GENERIC_READ | OS.Constants.Win.GENERIC_WRITE,
+    OS.Constants.Win.FILE_SHARE_READ | OS.Constants.FILE_SHARE_WRITE,
+    null,
+    OS.Constants.Win.CREATE_ALWAYS,
+    OS.Constants.Win.FILE_ATTRIBUTE_NORMAL,
+    null);
+  isnot(file, OS.Constants.Win.INVALID_HANDLE_VALUE, "test_CreateFile: opening succeeded");
+  let result = OS.Win.File.CloseHandle(file);
+  isnot(result, 0, "test_CreateFile: close succeeded");
+}
+
+function test_GetCurrentDirectory()
+{
+  let array = new (ctypes.ArrayType(ctypes.char16_t, 4096))();
+  let result = OS.Win.File.GetCurrentDirectory(4096, array);
+  ok(result < array.length, "test_GetCurrentDirectory: length sufficient");
+  ok(result > 0, "test_GetCurrentDirectory: length != 0");
+}
+
+function test_ReadWrite()
+{
+  info("Starting test_ReadWrite");
+  let output_name = "osfile_copy.tmp";
+  // Copy file
+  let input = OS.Win.File.CreateFile(
+    "chrome\\toolkit\\components\\osfile\\tests\\mochi\\worker_test_osfile_win.js",
+     OS.Constants.Win.GENERIC_READ,
+     0,
+     null,
+     OS.Constants.Win.OPEN_EXISTING,
+     0,
+     null);
+  isnot(input, OS.Constants.Win.INVALID_HANDLE_VALUE, "test_ReadWrite: input file opened");
+  let output = OS.Win.File.CreateFile(
+     "osfile_copy.tmp",
+     OS.Constants.Win.GENERIC_READ | OS.Constants.Win.GENERIC_WRITE,
+     0,
+     null,
+     OS.Constants.Win.CREATE_ALWAYS,
+     OS.Constants.Win.FILE_ATTRIBUTE_NORMAL,
+     null);
+  isnot(output, OS.Constants.Win.INVALID_HANDLE_VALUE, "test_ReadWrite: output file opened");
+  let array = new (ctypes.ArrayType(ctypes.char, 4096))();
+  let bytes_read = new ctypes.uint32_t(0);
+  let bytes_read_ptr = bytes_read.address();
+  log("We have a pointer for bytes read: "+bytes_read_ptr);
+  let bytes_written = new ctypes.uint32_t(0);
+  let bytes_written_ptr = bytes_written.address();
+  log("We have a pointer for bytes written: "+bytes_written_ptr);
+  log("test_ReadWrite: buffer and pointers ready");
+  let result;
+  while (true) {
+    log("test_ReadWrite: reading");
+    result = OS.Win.File.ReadFile(input, array, 4096, bytes_read_ptr, null);
+    isnot (result, 0, "test_ReadWrite: read success");
+    let write_from = 0;
+    let bytes_left = bytes_read;
+    log("test_ReadWrite: read chunk complete " + bytes_left.value);
+    if (bytes_left.value == 0) {
+      break;
+    }
+    while (bytes_left.value > 0) {
+      log("test_ReadWrite: writing "+bytes_left.value);
+      let ptr = array.addressOfElement(write_from);
+      // Note: |WriteFile| launches an exception in case of error
+      result = OS.Win.File.WriteFile(output, array, bytes_left, bytes_written_ptr, null);
+      isnot (result, 0, "test_ReadWrite: write success");
+      write_from += bytes_written;
+      bytes_left -= bytes_written;
+    }
+  }
+  info("test_ReadWrite: copy complete");
+
+  // Compare files
+  result = OS.Win.File.SetFilePointer(input, 0, null, OS.Constants.Win.FILE_BEGIN);
+  isnot (result, OS.Constants.Win.INVALID_SET_FILE_POINTER, "test_ReadWrite: input reset");
+
+  result = OS.Win.File.SetFilePointer(output, 0, null, OS.Constants.Win.FILE_BEGIN);
+  isnot (result, OS.Constants.Win.INVALID_SET_FILE_POINTER, "test_ReadWrite: output reset");
+
+  let array2 = new (ctypes.ArrayType(ctypes.char, 4096))();
+  let bytes_read2 = new ctypes.uint32_t(0);
+  let bytes_read2_ptr = bytes_read2.address();
+  let pos = 0;
+  while (true) {
+    result = OS.Win.File.ReadFile(input, array, 4096, bytes_read_ptr, null);
+    isnot(result, 0, "test_ReadWrite: input read succeeded");
+
+    result = OS.Win.File.ReadFile(output, array2, 4096, bytes_read2_ptr, null);
+    isnot(result, 0, "test_ReadWrite: output read succeeded");
+
+    is(bytes_read.value > 0, bytes_read2.value > 0,
+       "Both files contain data or neither does " + bytes_read.value + ", " + bytes_read2.value);
+    if (bytes_read.value == 0) {
+      break;
+    }
+    let bytes;
+    if (bytes_read.value != bytes_read2.value) {
+      // This would be surprising, but theoretically possible with a
+      // remote file system, I believe.
+      bytes = Math.min(bytes_read.value, bytes_read2.value);
+      pos += bytes;
+      result = OS.Win.File.SetFilePointer(input,  pos, null, OS.Constants.Win.FILE_BEGIN);
+      isnot(result, 0, "test_ReadWrite: input seek succeeded");
+
+      result = OS.Win.File.SetFilePointer(output, pos, null, OS.Constants.Win.FILE_BEGIN);
+      isnot(result, 0, "test_ReadWrite: output seek succeeded");
+
+    } else {
+      bytes = bytes_read.value;
+      pos += bytes;
+    }
+    for (let i = 0; i < bytes; ++i) {
+      if (array[i] != array2[i]) {
+        ok(false, "Files do not match at position " + i
+           + " ("+array[i] + "/"+array2[i] + ")");
+      }
+    }
+  }
+  info("test_ReadWrite test complete");
+  result = OS.Win.File.CloseHandle(input);
+  isnot(result, 0, "test_ReadWrite: inpout close succeeded");
+  result = OS.Win.File.CloseHandle(output);
+  isnot(result, 0, "test_ReadWrite: outpout close succeeded");
+  result = OS.Win.File.DeleteFile(output_name);
+  isnot(result, 0, "test_ReadWrite: output remove succeeded");
+  info("test_ReadWrite cleanup complete");
+}
+
+function test_passing_undefined()
+{
+  info("Testing that an exception gets thrown when an FFI function is passed undefined");
+  let exceptionRaised = false;
+
+  try {
+    let file = OS.Win.File.CreateFile(
+      undefined,
+      OS.Constants.Win.GENERIC_READ,
+      0,
+      null,
+      OS.Constants.Win.OPEN_EXISTING,
+      0,
+      null);
+  } catch(e if e instanceof TypeError && e.message.indexOf("CreateFile") > -1) {
+    exceptionRaised = true;
+  }
+
+  ok(exceptionRaised, "test_passing_undefined: exception gets thrown")
+}