[Extension API Extern Generation] Fix a few bugs in extern generation

tools/json_schema_compiler/code_test.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from code import Code
 import unittest
 
 class CodeTest(unittest.TestCase):
   def testAppend(self):
@@ skipping 173 matching lines @@
         '/**\n'
         ' * @typedef {{\n'
         ' *   foo: bar,\n'
         ' *   baz: {\n'
         ' *     x: y\n'
         ' *   }\n'
         ' * }}\n'
         ' */',
         output)
 
-  def testSameLineAppendAndConcat(self):
+  def testSameLineAppendConcatComment(self):
     c = Code()
     c.Append('This is a line.')
     c.Append('This too.', new_line=False)
     d = Code()
     d.Append('And this.')
     c.Concat(d, new_line=False)
     self.assertEquals('This is a line.This too.And this.', c.Render())
+    c = Code()
+    c.Append('This is a')
+    c.Comment(' spectacular 80-character line thingy ' +
+                  'that fits wonderfully everywhere.',
+              comment_prefix='',
+              new_line=False)
+    self.assertEquals('This is a spectacular 80-character line thingy that ' +
+                          'fits wonderfully everywhere.',
+                      c.Render())
 
 if __name__ == '__main__':
   unittest.main()