Add a new 'format-webkitpy' command that will reformat code to the style guide.

Tools/Scripts/webkitpy/formatter/main.py

+# Copyright 2014 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.
+
+import argparse
+import lib2to3.refactor
+
+from webkitpy.common.system.systemhost import SystemHost
+from webkitpy.thirdparty import autopep8
+
+
+def parse_args(args=None):
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--chromium', action='store_const', dest='style', const='chromium', default='blink',
+                        help="format according to Chromium's Python coding styles instead of Blink's")
+    parser.add_argument('--no-backups', action='store_false', default=True, dest='backup',
+                        help='do not back up files before overwriting them')
+    parser.add_argument('-j', '--jobs', metavar='n', type=int, default=0,
+                        help='number of parallel jobs; match CPU count if less than 1')
+    parser.add_argument('files', nargs='*', default=['-'],
+                        help="files to format or '-' for standard in")
+    return parser.parse_args(args=args)
+
+
+def main(host=None, args=None):
+    options = parse_args(args)
+
+    if options.files == ['-']:
+        host = host or SystemHost()
+        host.print_(reformat_source(host.stdin.read(), options.style, '<stdin>'), end='')
+        return
+
+    # We create the arglist before checking if we need to create a Host, because a
+    # real host is non-picklable and can't be passed to host.executive.map().
+    arglist = [(host, name, options.style, options.backup) for name in options.files]
+    host = host or SystemHost()
+
+    host.executive.map(_reformat_thunk, arglist, processes=options.jobs)
+
+
+def _reformat_thunk(args):
+    reformat_file(*args)
+
+
+def reformat_file(host, name, style, should_backup_file):
+    host = host or SystemHost()
+    source = host.filesystem.read_text_file(name)
+    dest = reformat_source(source, style, name)
+    if dest != source:
+        if should_backup_file:
+            host.filesystem.write_text_file(name + '.bak', source)
+        host.filesystem.write_text_file(name, dest)
+
+
+def reformat_source(source, style, name):
+    options = _autopep8_options_for_style(style)
+    tmp_str = autopep8.fix_code(source, options)
+
+    fixers = _fixers_for_style(style)
+    tool = lib2to3.refactor.RefactoringTool(fixer_names=fixers,
+                                            explicit=fixers)
+    return unicode(tool.refactor_string(tmp_str, name=name))
+
+
+def _autopep8_options_for_style(style):
+    if style == 'chromium':
+        max_line_length = 80
+        indent_size = 2
+    else:
+        max_line_length = 132
+        indent_size = 4
+
+    return autopep8.parse_args(['--aggressive',
+                                '--max-line-length', str(max_line_length),
+                                '--indent-size', str(indent_size),
+                                ''])
+
+
+def _fixers_for_style(style):
+    if style == 'chromium':
+        return ['webkitpy.formatter.fix_double_quote_strings']
+    else:
+        return ['webkitpy.formatter.fix_single_quote_strings']