diff --git a/js/binary/writer_test.js b/js/binary/writer_test.js
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+++ b/js/binary/writer_test.js
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+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/**
+ * @fileoverview Test cases for jspb's binary protocol buffer writer. In
+ * practice BinaryWriter is used to drive the Decoder and Reader test cases,
+ * so only writer-specific tests are here.
+ *
+ * Test suite is written using Jasmine -- see http://jasmine.github.io/
+ *
+ * @author aappleby@google.com (Austin Appleby)
+ */
+
+goog.require('goog.crypt');
+goog.require('goog.testing.asserts');
+goog.require('jspb.BinaryWriter');
+
+
+/**
+ * @param {function()} func This function should throw an error when run.
+ */
+function assertFails(func) {
+  var e = assertThrows(func);
+  console.log(e);
+  //assertNotNull(e.toString().match(/Error/));
+}
+
+
+describe('binaryWriterTest', function() {
+  /**
+   * Verifies that misuse of the writer class triggers assertions.
+   */
+  it('testWriteErrors', function() {
+    // Submessages with invalid field indices should assert.
+    var writer = new jspb.BinaryWriter();
+    var dummyMessage = /** @type {!jspb.BinaryMessage} */({});
+
+    assertFails(function() {
+      writer.writeMessage(-1, dummyMessage, goog.nullFunction);
+    });
+
+    // Writing invalid field indices should assert.
+    writer = new jspb.BinaryWriter();
+    assertFails(function() {writer.writeUint64(-1, 1);});
+
+    // Writing out-of-range field values should assert.
+    writer = new jspb.BinaryWriter();
+
+    assertFails(function() {writer.writeInt32(1, -Infinity);});
+    assertFails(function() {writer.writeInt32(1, Infinity);});
+
+    assertFails(function() {writer.writeInt64(1, -Infinity);});
+    assertFails(function() {writer.writeInt64(1, Infinity);});
+
+    assertFails(function() {writer.writeUint32(1, -1);});
+    assertFails(function() {writer.writeUint32(1, Infinity);});
+
+    assertFails(function() {writer.writeUint64(1, -1);});
+    assertFails(function() {writer.writeUint64(1, Infinity);});
+
+    assertFails(function() {writer.writeSint32(1, -Infinity);});
+    assertFails(function() {writer.writeSint32(1, Infinity);});
+
+    assertFails(function() {writer.writeSint64(1, -Infinity);});
+    assertFails(function() {writer.writeSint64(1, Infinity);});
+
+    assertFails(function() {writer.writeFixed32(1, -1);});
+    assertFails(function() {writer.writeFixed32(1, Infinity);});
+
+    assertFails(function() {writer.writeFixed64(1, -1);});
+    assertFails(function() {writer.writeFixed64(1, Infinity);});
+
+    assertFails(function() {writer.writeSfixed32(1, -Infinity);});
+    assertFails(function() {writer.writeSfixed32(1, Infinity);});
+
+    assertFails(function() {writer.writeSfixed64(1, -Infinity);});
+    assertFails(function() {writer.writeSfixed64(1, Infinity);});
+  });
+
+
+  /**
+   * Basic test of retrieving the result as a Uint8Array buffer
+   */
+  it('testGetResultBuffer', function() {
+    var expected = '0864120b48656c6c6f20776f726c641a0301020320c801';
+
+    var writer = new jspb.BinaryWriter();
+    writer.writeUint32(1, 100);
+    writer.writeString(2, 'Hello world');
+    writer.writeBytes(3, new Uint8Array([1, 2, 3]));
+    writer.writeUint32(4, 200);
+
+    var buffer = writer.getResultBuffer();
+    assertEquals(expected, goog.crypt.byteArrayToHex(buffer));
+  });
+});