Improve default email address for my_reviews.py

my_reviews.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.
 
 """Get rietveld stats about the review you done, or forgot to do.
 
 Example:
   - my_reviews.py -r me@chromium.org -Q  for stats for last quarter.
 """
@@ skipping 99 matching lines @@
 
   def finalize(self, first_day, last_day):
     if self.actually_reviewed:
       assert self.actually_reviewed > 0
       self.percent_lgtm = (self.lgtms * 100. / self.actually_reviewed)
       self.percent_drive_by = (self.drive_by * 100. / self.actually_reviewed)
       self.percent_not_requested = (
           self.not_requested * 100. / self.actually_reviewed)
     assert bool(first_day) == bool(last_day)
     if first_day and last_day:
-      assert first_day < last_day
+      assert first_day <= last_day
       self.days = (to_datetime(last_day) - to_datetime(first_day)).days + 1
       assert self.days > 0
 
 
 def _process_issue_lgtms(issue, reviewer, stats):
   """Calculates LGTMs stats."""
   stats.actually_reviewed += 1
   reviewer_lgtms = len([
     msg for msg in issue['messages']
     if msg['approval'] and msg['sender'] == reviewer])
@@ skipping 168 matching lines @@
     begin_month += 12
   begin = '%d-%02d-01' % (begin_year, begin_month)
   return begin, end
 
 
 def main():
   # Silence upload.py.
   rietveld.upload.verbosity = 0
   today = datetime.date.today()
   begin, end = get_previous_quarter(today)
-  parser = optparse.OptionParser(description=sys.modules[__name__].__doc__)
+  default_email = os.environ.get('EMAIL_ADDRESS')
+  if not default_email:
+    user = os.environ.get('USER')
+    if user:
+      default_email = user + '@chromium.org'
+
+  parser = optparse.OptionParser(description=__doc__)
   parser.add_option(
       '--count', action='store_true',
       help='Just count instead of printing individual issues')
   parser.add_option(
-      '-r', '--reviewer', metavar='<email>',
-      default=os.environ.get('EMAIL_ADDRESS'),
+      '-r', '--reviewer', metavar='<email>', default=default_email,
       help='Filter on issue reviewer, default=%default')
   parser.add_option(
       '-b', '--begin', metavar='<date>',
       help='Filter issues created after the date')
   parser.add_option(
       '-e', '--end', metavar='<date>',
       help='Filter issues created before the date')
   parser.add_option(
       '-Q', '--last_quarter', action='store_true',
-      help='Use last quarter\'s dates, e.g. %s to %s' % (
-        begin, end))
+      help='Use last quarter\'s dates, e.g. %s to %s' % (begin, end))
   parser.add_option(
       '-i', '--instance_url', metavar='<host>',
       default='http://codereview.chromium.org',
       help='Host to use, default is %default')
   # Remove description formatting
   parser.format_description = (
       lambda _: parser.description)  # pylint: disable=E1101
   options, args = parser.parse_args()
   if args:
     parser.error('Args unsupported')
-  if not options.reviewer:
-    parser.error('$EMAIL_ADDRESS is not set, please use -r')
+  if options.reviewer is None:
+    parser.error('$EMAIL_ADDRESS and $USER are not set, please use -r')
+
   print >> sys.stderr, 'Searching for reviews by %s' % options.reviewer
   if options.last_quarter:
     options.begin = begin
     options.end = end
     print >> sys.stderr, 'Using range %s to %s' % (
         options.begin, options.end)
+  else:
+    if options.begin is None or options.end is None:
+      parser.error('Please specify either --last_quarter or --begin and --end')
 
   # Validate dates.
   try:
     to_datetime(options.begin)
     to_datetime(options.end)
   except ValueError as e:
     parser.error('%s: %s - %s' % (e, options.begin, options.end))
 
   if options.count:
     print_count(
         options.reviewer,
         options.begin,
         options.end,
         options.instance_url)
   else:
     print_reviews(
         options.reviewer,
         options.begin,
         options.end,
         options.instance_url)
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())