Further tweak compare_codereview.py.

tools/compare_codereview.py

Index: tools/compare_codereview.py
diff --git a/tools/compare_codereview.py b/tools/compare_codereview.py
index b39bfe2942bb7b687b07ba32a3689c77a3cf1284..a58b3c697bf2f105bbc70cd564bf6909b7d288ef 100755
--- a/tools/compare_codereview.py
+++ b/tools/compare_codereview.py
@@ -23,373 +23,392 @@ import HTMLParser
 
 
 class CodeReviewHTMLParser(HTMLParser.HTMLParser):
-    """Parses CodeReview web page.
+  """Parses CodeReview web page.
 
-    Use the CodeReviewHTMLParser.parse static function to make use of
-    this class.
+  Use the CodeReviewHTMLParser.parse static function to make use of
+  this class.
 
-    This uses the HTMLParser class because it's the best thing in
-    Python's standard library.  We need a little more power than a
-    regex.  [Search for "You can't parse [X]HTML with regex." for more
-    information.
+  This uses the HTMLParser class because it's the best thing in
+  Python's standard library.  We need a little more power than a
+  regex.  [Search for "You can't parse [X]HTML with regex." for more
+  information.
+  """
+  # pylint: disable=I0011,R0904
+  @staticmethod
+  def parse(url):
+    """Parses a CodeReview web pages.
+
+    Args:
+      url (string), a codereview URL like this:
+        'https://codereview.chromium.org/?????????'.
+
+    Returns:
+      A dictionary; the keys are bot_name strings, the values
+      are CodeReviewHTMLParser.Status objects
+    """
+    parser = CodeReviewHTMLParser()
+    try:
+      parser.feed(urllib2.urlopen(url).read())
+    except (urllib2.URLError,):
+      print >> sys.stderr, 'Error getting', url
+      return None
+    parser.close()
+    return parser.statuses
+
+  # namedtuples are like lightweight structs in Python.  The low
+  # overhead of a tuple, but the ease of use of an object.
+  Status = collections.namedtuple('Status', ['status', 'url'])
+
+  def __init__(self):
+    HTMLParser.HTMLParser.__init__(self)
+    self._id = None
+    self._status = None
+    self._href = None
+    self._anchor_data = ''
+    self._currently_parsing_trybotdiv = False
+    # statuses is a dictionary of CodeReviewHTMLParser.Status
+    self.statuses = {}
+
+  def handle_starttag(self, tag, attrs):
+    """Overrides the HTMLParser method to implement functionality.
+
+    [[begin standard library documentation]]
+    This method is called to handle the start of a tag
+    (e.g. <div id="main">).
+
+    The tag argument is the name of the tag converted to lower
+    case. The attrs argument is a list of (name, value) pairs
+    containing the attributes found inside the tag's <>
+    brackets. The name will be translated to lower case, and
+    quotes in the value have been removed, and character and
+    entity references have been replaced.
+
+    For instance, for the tag <A HREF="http://www.cwi.nl/">, this
+    method would be called as handle_starttag('a', [('href',
+    'http://www.cwi.nl/')]).
+    [[end standard library documentation]]
     """
-    # pylint: disable=I0011,R0904
-    @staticmethod
-    def parse(url):
-        """Parses a CodeReview web pages.
-
-        Args:
-            url (string), a codereview URL like this:
-                'https://codereview.chromium.org/?????????'.
-
-        Returns:
-            A dictionary; the keys are bot_name strings, the values
-            are CodeReviewHTMLParser.Status objects
-        """
-        parser = CodeReviewHTMLParser()
-        try:
-            parser.feed(urllib2.urlopen(url).read())
-        except (urllib2.URLError,):
-            print >> sys.stderr, 'Error getting', url
-            return None
-        parser.close()
-        return parser.statuses
-
-    # namedtuples are like lightweight structs in Python.  The low
-    # overhead of a tuple, but the ease of use of an object.
-    Status = collections.namedtuple('Status', ['status', 'url'])
-
-    def __init__(self):
-        HTMLParser.HTMLParser.__init__(self)
-        self._id = None
-        self._status = None
-        self._href = None
-        self._anchor_data = ''
-        self._currently_parsing_trybotdiv = False
-        # statuses is a dictionary of CodeReviewHTMLParser.Status
-        self.statuses = {}
-
-    def handle_starttag(self, tag, attrs):
-        """Overrides the HTMLParser method to implement functionality.
-
-        [[begin standard library documentation]]
-        This method is called to handle the start of a tag
-        (e.g. <div id="main">).
-
-        The tag argument is the name of the tag converted to lower
-        case. The attrs argument is a list of (name, value) pairs
-        containing the attributes found inside the tag's <>
-        brackets. The name will be translated to lower case, and
-        quotes in the value have been removed, and character and
-        entity references have been replaced.
-
-        For instance, for the tag <A HREF="http://www.cwi.nl/">, this
-        method would be called as handle_starttag('a', [('href',
-        'http://www.cwi.nl/')]).
-        [[end standard library documentation]]
-        """
-        attrs = dict(attrs)
-        if tag == 'div':
-            # We are looking for <div id="tryjobdiv*">.
-            id_attr = attrs.get('id','')
-            if id_attr.startswith('tryjobdiv'):
-                self._id = id_attr
-        if (self._id and tag == 'a'
-            and 'build-result' in attrs.get('class', '').split()):
-            # If we are already inside a <div id="tryjobdiv*">, we
-            # look for a link if the form
-            # <a class="build-result" href="*">.  Then we save the
-            # (non-standard) status attribute and the URL.
-            self._status = attrs.get('status')
-            self._href = attrs.get('href')
-            self._currently_parsing_trybotdiv = True
-            # Start saving anchor data.
-
-    def handle_data(self, data):
-        """Overrides the HTMLParser method to implement functionality.
-
-        [[begin standard library documentation]]
-        This method is called to process arbitrary data (e.g. text
-        nodes and the content of <script>...</script> and
-        <style>...</style>).
-        [[end standard library documentation]]
-        """
-        # Save the text inside the <a></a> tags.  Assume <a> tags
-        # aren't nested.
-        if self._currently_parsing_trybotdiv:
-            self._anchor_data += data
-
-    def handle_endtag(self, tag):
-        """Overrides the HTMLParser method to implement functionality.
-
-        [[begin standard library documentation]]
-        This method is called to handle the end tag of an element
-        (e.g. </div>).  The tag argument is the name of the tag
-        converted to lower case.
-        [[end standard library documentation]]
-        """
-        if tag == 'a' and self._status:
-            # We take the accumulated self._anchor_data and save it as
-            # the bot name.
-            bot = self._anchor_data.strip()
-            stat = CodeReviewHTMLParser.Status(status=self._status,
-                                               url=self._href)
-            if bot:
-                # Add to accumulating dictionary.
-                self.statuses[bot] = stat
-            # Reset state to search for the next bot.
-            self._currently_parsing_trybotdiv = False
-            self._anchor_data = ''
-            self._status = None
-            self._href = None
+    attrs = dict(attrs)
+    if tag == 'div':
+      # We are looking for <div id="tryjobdiv*">.
+      id_attr = attrs.get('id','')
+      if id_attr.startswith('tryjobdiv'):
+        self._id = id_attr
+    if (self._id and tag == 'a'
+      and 'build-result' in attrs.get('class', '').split()):
+      # If we are already inside a <div id="tryjobdiv*">, we
+      # look for a link if the form
+      # <a class="build-result" href="*">.  Then we save the
+      # (non-standard) status attribute and the URL.
+      self._status = attrs.get('status')
+      self._href = attrs.get('href')
+      self._currently_parsing_trybotdiv = True
+      # Start saving anchor data.
+
+  def handle_data(self, data):
+    """Overrides the HTMLParser method to implement functionality.
+
+    [[begin standard library documentation]]
+    This method is called to process arbitrary data (e.g. text
+    nodes and the content of <script>...</script> and
+    <style>...</style>).
+    [[end standard library documentation]]
+    """
+    # Save the text inside the <a></a> tags.  Assume <a> tags
+    # aren't nested.
+    if self._currently_parsing_trybotdiv:
+      self._anchor_data += data
+
+  def handle_endtag(self, tag):
+    """Overrides the HTMLParser method to implement functionality.
+
+    [[begin standard library documentation]]
+    This method is called to handle the end tag of an element
+    (e.g. </div>).  The tag argument is the name of the tag
+    converted to lower case.
+    [[end standard library documentation]]
+    """
+    if tag == 'a' and self._status:
+      # We take the accumulated self._anchor_data and save it as
+      # the bot name.
+      bot = self._anchor_data.strip()
+      stat = CodeReviewHTMLParser.Status(status=self._status,
+                         url=self._href)
+      if bot:
+        # Add to accumulating dictionary.
+        self.statuses[bot] = stat
+      # Reset state to search for the next bot.
+      self._currently_parsing_trybotdiv = False
+      self._anchor_data = ''
+      self._status = None
+      self._href = None
 
 
 class BuilderHTMLParser(HTMLParser.HTMLParser):
-    """parses Trybot web pages.
+  """parses Trybot web pages.
 
-    Use the BuilderHTMLParser.parse static function to make use of
-    this class.
-
-    This uses the HTMLParser class because it's the best thing in
-    Python's standard library.  We need a little more power than a
-    regex.  [Search for "You can't parse [X]HTML with regex." for more
-    information.
-    """
-    # pylint: disable=I0011,R0904
-    @staticmethod
-    def parse(url):
-        """Parses a Trybot web page.
-
-        Args:
-            url (string), a trybot result URL.
-
-        Returns:
-            An array of BuilderHTMLParser.Results, each a description
-            of failure results, along with an optional url
-        """
-        parser = BuilderHTMLParser()
-        try:
-            parser.feed(urllib2.urlopen(url).read())
-        except (urllib2.URLError,):
-            print >> sys.stderr, 'Error getting', url
-            return []
-        parser.close()
-        return parser.failure_results
-
-    Result = collections.namedtuple('Result', ['text', 'url'])
-
-    def __init__(self):
-        HTMLParser.HTMLParser.__init__(self)
-        self.failure_results = []
-        self._current_failure_result = None
-        self._divlevel = None
-        self._li_level = 0
-        self._li_data = ''
-        self._current_failure = False
-        self._failure_results_url = ''
+  Use the BuilderHTMLParser.parse static function to make use of
+  this class.
 
-    def handle_starttag(self, tag, attrs):
-        """Overrides the HTMLParser method to implement functionality.
-
-        [[begin standard library documentation]]
-        This method is called to handle the start of a tag
-        (e.g. <div id="main">).
-
-        The tag argument is the name of the tag converted to lower
-        case. The attrs argument is a list of (name, value) pairs
-        containing the attributes found inside the tag's <>
-        brackets. The name will be translated to lower case, and
-        quotes in the value have been removed, and character and
-        entity references have been replaced.
-
-        For instance, for the tag <A HREF="http://www.cwi.nl/">, this
-        method would be called as handle_starttag('a', [('href',
-        'http://www.cwi.nl/')]).
-        [[end standard library documentation]]
-        """
-        attrs = dict(attrs)
-        if tag == 'li':
-            # <li> tags can be nested.  So we have to count the
-            # nest-level for backing out.
-            self._li_level += 1
-            return
-        if tag == 'div' and attrs.get('class') == 'failure result':
-            # We care about this sort of thing:
-            # <li>
-            #   <li>
-            #     <li>
-            #       <div class="failure result">...</div>
-            #     </li>
-            #   </li>
-            #   We want this text here.
-            # </li>
-            if self._li_level > 0:
-                self._current_failure = True  # Tells us to keep text.
-            return
-
-        if tag == 'a' and self._current_failure:
-            href = attrs.get('href')
-            # Sometimes we want to keep the stdio url.  We always
-            # return it, just in case.
-            if href.endswith('/logs/stdio'):
-                self._failure_results_url = href
-
-    def handle_data(self, data):
-        """Overrides the HTMLParser method to implement functionality.
-
-        [[begin standard library documentation]]
-        This method is called to process arbitrary data (e.g. text
-        nodes and the content of <script>...</script> and
-        <style>...</style>).
-        [[end standard library documentation]]
-        """
-        if self._current_failure:
-            self._li_data += data
-
-    def handle_endtag(self, tag):
-        """Overrides the HTMLParser method to implement functionality.
-
-        [[begin standard library documentation]]
-        This method is called to handle the end tag of an element
-        (e.g. </div>).  The tag argument is the name of the tag
-        converted to lower case.
-        [[end standard library documentation]]
-        """
-        if tag == 'li':
-            self._li_level -= 1
-            if 0 == self._li_level:
-                if self._current_failure:
-                    result = self._li_data.strip()
-                    first = result.split()[0]
-                    if first:
-                        result = re.sub(
-                            r'^%s(\s+%s)+' % (first, first), first, result)
-                        # Sometimes, it repeats the same thing
-                        # multiple times.
-                    result = re.sub(r'unexpected flaky.*', '', result)
-                    # Remove some extra unnecessary text.
-                    result = re.sub(r'\bpreamble\b', '', result)
-                    result = re.sub(r'\bstdio\b', '', result)
-                    url = self._failure_results_url
-                    self.failure_results.append(
-                        BuilderHTMLParser.Result(result, url))
-                    self._current_failure_result = None
-                # Reset the state.
-                self._current_failure = False
-                self._li_data = ''
-                self._failure_results_url = ''
+  This uses the HTMLParser class because it's the best thing in
+  Python's standard library.  We need a little more power than a
+  regex.  [Search for "You can't parse [X]HTML with regex." for more
+  information.
+  """
+  # pylint: disable=I0011,R0904
+  @staticmethod
+  def parse(url):
+    """Parses a Trybot web page.
 
+    Args:
+      url (string), a trybot result URL.
 
-def printer(indent, string):
-    """Print indented, wrapped text.
+    Returns:
+      An array of BuilderHTMLParser.Results, each a description
+      of failure results, along with an optional url
     """
-    def wrap_to(line, columns):
-        """Wrap a line to the given number of columns, return a list
-        of strings.
-        """
-        ret = []
-        nextline = ''
-        for word in line.split():
-            if nextline:
-                if len(nextline) + 1 + len(word) > columns:
-                    ret.append(nextline)
-                    nextline = word
-                else:
-                    nextline += (' ' + word)
-            else:
-                nextline = word
-        if nextline:
-            ret.append(nextline)
-        return ret
-    out = sys.stdout
-    spacer = '  '
-    for line in string.split('\n'):
-        for i, wrapped_line in enumerate(wrap_to(line, 68 - (2 * indent))):
-            out.write(spacer * indent)
-            if i > 0:
-                out.write(spacer)
-            out.write(wrapped_line)
-            out.write('\n')
-    out.flush()
+    parser = BuilderHTMLParser()
+    try:
+      parser.feed(urllib2.urlopen(url).read())
+    except (urllib2.URLError,):
+      print >> sys.stderr, 'Error getting', url
+      return []
+    parser.close()
+    return parser.failure_results
+
+  Result = collections.namedtuple('Result', ['text', 'url'])
+
+  def __init__(self):
+    HTMLParser.HTMLParser.__init__(self)
+    self.failure_results = []
+    self._current_failure_result = None
+    self._divlevel = None
+    self._li_level = 0
+    self._li_data = ''
+    self._current_failure = False
+    self._failure_results_url = ''
+
+  def handle_starttag(self, tag, attrs):
+    """Overrides the HTMLParser method to implement functionality.
+
+    [[begin standard library documentation]]
+    This method is called to handle the start of a tag
+    (e.g. <div id="main">).
+
+    The tag argument is the name of the tag converted to lower
+    case. The attrs argument is a list of (name, value) pairs
+    containing the attributes found inside the tag's <>
+    brackets. The name will be translated to lower case, and
+    quotes in the value have been removed, and character and
+    entity references have been replaced.
+
+    For instance, for the tag <A HREF="http://www.cwi.nl/">, this
+    method would be called as handle_starttag('a', [('href',
+    'http://www.cwi.nl/')]).
+    [[end standard library documentation]]
+    """
+    attrs = dict(attrs)
+    if tag == 'li':
+      # <li> tags can be nested.  So we have to count the
+      # nest-level for backing out.
+      self._li_level += 1
+      return
+    if tag == 'div' and attrs.get('class') == 'failure result':
+      # We care about this sort of thing:
+      # <li>
+      #   <li>
+      #   <li>
+      #     <div class="failure result">...</div>
+      #   </li>
+      #   </li>
+      #   We want this text here.
+      # </li>
+      if self._li_level > 0:
+        self._current_failure = True  # Tells us to keep text.
+      return
+
+    if tag == 'a' and self._current_failure:
+      href = attrs.get('href')
+      # Sometimes we want to keep the stdio url.  We always
+      # return it, just in case.
+      if href.endswith('/logs/stdio'):
+        self._failure_results_url = href
+
+  def handle_data(self, data):
+    """Overrides the HTMLParser method to implement functionality.
+
+    [[begin standard library documentation]]
+    This method is called to process arbitrary data (e.g. text
+    nodes and the content of <script>...</script> and
+    <style>...</style>).
+    [[end standard library documentation]]
+    """
+    if self._current_failure:
+      self._li_data += data
 
+  def handle_endtag(self, tag):
+    """Overrides the HTMLParser method to implement functionality.
 
-def main(control_url, roll_url, verbosity=1):
-    """Compare two Codereview URLs
+    [[begin standard library documentation]]
+    This method is called to handle the end tag of an element
+    (e.g. </div>).  The tag argument is the name of the tag
+    converted to lower case.
+    [[end standard library documentation]]
+    """
+    if tag == 'li':
+      self._li_level -= 1
+      if 0 == self._li_level:
+        if self._current_failure:
+          result = self._li_data.strip()
+          first = result.split()[0]
+          if first:
+            result = re.sub(
+              r'^%s(\s+%s)+' % (first, first), first, result)
+            # Sometimes, it repeats the same thing
+            # multiple times.
+          result = re.sub(r'unexpected flaky.*', '', result)
+          # Remove some extra unnecessary text.
+          result = re.sub(r'\bpreamble\b', '', result)
+          result = re.sub(r'\bstdio\b', '', result)
+          url = self._failure_results_url
+          self.failure_results.append(
+            BuilderHTMLParser.Result(result, url))
+          self._current_failure_result = None
+        # Reset the state.
+        self._current_failure = False
+        self._li_data = ''
+        self._failure_results_url = ''
 
-    Args:
-        control_url, roll_url: (strings) URL of the format
-            https://codereview.chromium.org/?????????
 
-        verbosity: (int) verbose level.  0, 1, or 2.
+def printer(indent, string):
+  """Print indented, wrapped text.
+  """
+  def wrap_to(line, columns):
+    """Wrap a line to the given number of columns, return a list
+    of strings.
     """
-    # pylint: disable=I0011,R0914,R0912
-    control = CodeReviewHTMLParser.parse(control_url)
-    roll = CodeReviewHTMLParser.parse(roll_url)
-    all_bots = set(control) & set(roll)  # Set intersection.
-    if not all_bots:
-        print >> sys.stderr, (
-            'Error:  control %s and roll %s have no common trybots.'
-            % (list(control), list(roll)))
-        return
-
-    control_name = '[control %s]' % control_url.split('/')[-1]
-    roll_name = '[roll %s]' % roll_url.split('/')[-1]
+    ret = []
+    nextline = ''
+    for word in line.split():
+      if nextline:
+        if len(nextline) + 1 + len(word) > columns:
+          ret.append(nextline)
+          nextline = word
+        else:
+          nextline += (' ' + word)
+      else:
+        nextline = word
+    if nextline:
+      ret.append(nextline)
+    return ret
+  out = sys.stdout
+  spacer = '  '
+  for line in string.split('\n'):
+    for i, wrapped_line in enumerate(wrap_to(line, 68 - (2 * indent))):
+      out.write(spacer * indent)
+      if i > 0:
+        out.write(spacer)
+      out.write(wrapped_line)
+      out.write('\n')
+  out.flush()
 
-    out = sys.stdout
 
-    for bot in sorted(all_bots):
-        if (roll[bot].status == 'success'):
-            if verbosity > 1:
-                printer(0, '==%s==' % bot)
-                printer(1, 'OK')
-            continue
+def main(control_url, roll_url, verbosity=1):
+  """Compare two Codereview URLs
+
+  Args:
+    control_url, roll_url: (strings) URL of the format
+      https://codereview.chromium.org/?????????
+
+    verbosity: (int) verbose level.  0, 1, or 2.
+  """
+  # pylint: disable=I0011,R0914,R0912
+  control = CodeReviewHTMLParser.parse(control_url)
+  roll = CodeReviewHTMLParser.parse(roll_url)
+  all_bots = set(control) & set(roll)  # Set intersection.
+  if not all_bots:
+    print >> sys.stderr, (
+      'Error:  control %s and roll %s have no common trybots.'
+      % (list(control), list(roll)))
+    return
+
+  control_name = '[control %s]' % control_url.split('/')[-1]
+  roll_name = '[roll %s]' % roll_url.split('/')[-1]
+
+  out = sys.stdout
+
+  for bot in sorted(all_bots):
+    if (roll[bot].status == 'success'):
+      if verbosity > 1:
         printer(0, '==%s==' % bot)
+        printer(1, 'OK')
+      continue
 
-        for (status, name, url) in (
+    if control[bot].status != 'failure' and roll[bot].status != 'failure':
+      continue
+    printer(0, '==%s==' % bot)
+
+    formatted_results = []
+    for (status, name, url) in [
             (control[bot].status, control_name, control[bot].url),
-            (roll[bot].status, roll_name, roll[bot].url)):
-
-            if status == 'failure':
-                printer(1, name)
-                results = BuilderHTMLParser.parse(url)
-                for result in results:
-                    formatted_result = re.sub(
-                        r'(\S*\.html) ', '\n__\g<1>\n', result.text)
-                    # Strip runtimes.
-                    formatted_result = re.sub(r'\(.*\)', '', formatted_result)
-                    printer(2, formatted_result)
-                    if ('compile' in result.text
-                        or '...and more' in result.text):
-                        printer(3, re.sub('/[^/]*$', '/', url) + result.url)
-            else:
-                printer(1, name)
-                printer(2, status)
-        out.write('\n')
-
-    if verbosity > 0:
-        # Print out summary of all of the bots.
-        out.write('%11s %11s %4s %s\n\n' %
-                  ('CONTROL', 'ROLL', 'DIFF', 'BOT'))
-        for bot in sorted(all_bots):
-            if roll[bot].status == 'success':
-                diff = ''
-            elif (control[bot].status == 'success' and
-                     roll[bot].status == 'failure'):
-                diff = '!!!!'
-            elif ('pending' in control[bot].status or
-                  'pending' in roll[bot].status):
-                diff = '....'
-            else:
-                diff = '****'
-            out.write('%11s %11s %4s %s\n' % (
-                    control[bot].status, roll[bot].status, diff, bot))
-        out.write('\n')
-        out.flush()
+            (   roll[bot].status,    roll_name,    roll[bot].url)]:
+      lines = []
+      if status == 'failure':
+        results = BuilderHTMLParser.parse(url)
+        for result in results:
+          formatted_result = re.sub(r'(\S*\.html) ', '\n__\g<1>\n', result.text)
+          # Strip runtimes.
+          formatted_result = re.sub(r'\(.*\)', '', formatted_result)
+          lines.append((2, formatted_result))
+          if ('compile' in result.text or '...and more' in result.text):
+            lines.append((3, re.sub('/[^/]*$', '/', url) + result.url))
+      formatted_results.append(lines)
+
+    identical = formatted_results[0] == formatted_results[1]
+
+
+    for (formatted_result, (status, name, url)) in zip(
+        formatted_results,
+        [(control[bot].status, control_name, control[bot].url),
+          (roll[bot].status,  roll_name,  roll[bot].url)]):
+      if status != 'failure' and not identical:
+        printer(1, name)
+        printer(2, status)
+      elif status == 'failure':
+        if identical:
+          printer(1, control_name + ' and ' + roll_name + ' failed identically')
+        else:
+          printer(1, name)
+        for (indent, line) in formatted_result:
+          printer(indent, line)
+        if identical:
+          break
+    out.write('\n')
+
+  if verbosity > 0:
+    # Print out summary of all of the bots.
+    out.write('%11s %11s %4s %s\n\n' %
+          ('CONTROL', 'ROLL', 'DIFF', 'BOT'))
+    for bot in sorted(all_bots):
+      if roll[bot].status == 'success':
+        diff = ''
+      elif (control[bot].status == 'success' and
+           roll[bot].status == 'failure'):
+        diff = '!!!!'
+      elif ('pending' in control[bot].status or
+          'pending' in roll[bot].status):
+        diff = '....'
+      else:
+        diff = '****'
+      out.write('%11s %11s %4s %s\n' % (
+          control[bot].status, roll[bot].status, diff, bot))
+    out.write('\n')
+    out.flush()
 
 if __name__ == '__main__':
-    if len(sys.argv) < 3:
-        print >> sys.stderr, __doc__
-        exit(1)
-    main(sys.argv[1], sys.argv[2],
-         int(os.environ.get('COMPARE_CODEREVIEW_VERBOSITY', 1)))
+  if len(sys.argv) < 3:
+    print >> sys.stderr, __doc__
+    exit(1)
+  main(sys.argv[1], sys.argv[2],
+     int(os.environ.get('COMPARE_CODEREVIEW_VERBOSITY', 1)))