blob: 88bbd555c3952a64037f738d231b1e2e4f647a7a [file] [log] [blame]
#!/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.
"""Given a filename as an argument, sort the #include/#imports in that file.
Shows a diff and prompts for confirmation before doing the deed.
Works great with tools/git/for-all-touched-files.py.
"""
import optparse
import os
import sys
from yes_no import YesNo
def IsInclude(line):
"""Returns True if the line is an #include/#import/import line."""
return any([line.startswith('#include '), line.startswith('#import '),
line.startswith('import ')])
def IncludeCompareKey(line, for_blink):
"""Sorting comparator key used for comparing two #include lines.
Returns an integer, optionally followed by a string. The integer is used
for coarse sorting of different categories of headers, and the string is
used for fine sorting of headers within categeries.
"""
for prefix in ('#include ', '#import ', 'import '):
if line.startswith(prefix):
line = line[len(prefix):]
break
if for_blink:
# Blink likes to have its "config.h" include first.
if line.startswith('"config.h"'):
return '0'
# Blink sorts system headers after others. This is handled by sorting
# alphabetically so no need to do anything tricky.
return '1' + line
# The win32 api has all sorts of implicit include order dependencies :-/
# Give a few headers special sort keys that make sure they appear before all
# other headers.
if line.startswith('<windows.h>'): # Must be before e.g. shellapi.h
return '0'
if line.startswith('<atlbase.h>'): # Must be before atlapp.h.
return '1' + line
if line.startswith('<ole2.h>'): # Must be before e.g. intshcut.h
return '1' + line
if line.startswith('<unknwn.h>'): # Must be before e.g. intshcut.h
return '1' + line
# C++ system headers should come after C system headers.
if line.startswith('<'):
if line.find('.h>') != -1:
return '2' + line.lower()
else:
return '3' + line.lower()
return '4' + line
def SortHeader(infile, outfile, for_blink):
"""Sorts the headers in infile, writing the sorted file to outfile."""
def CompareKey(line):
return IncludeCompareKey(line, for_blink)
for line in infile:
if IsInclude(line):
headerblock = []
while IsInclude(line):
infile_ended_on_include_line = False
headerblock.append(line)
# Ensure we don't die due to trying to read beyond the end of the file.
try:
line = infile.next()
except StopIteration:
infile_ended_on_include_line = True
break
for header in sorted(headerblock, key=CompareKey):
outfile.write(header)
if infile_ended_on_include_line:
# We already wrote the last line above; exit to ensure it isn't written
# again.
return
# Intentionally fall through, to write the line that caused
# the above while loop to exit.
outfile.write(line)
def FixFileWithConfirmFunction(filename, confirm_function,
perform_safety_checks, for_blink=False):
"""Creates a fixed version of the file, invokes |confirm_function|
to decide whether to use the new file, and cleans up.
|confirm_function| takes two parameters, the original filename and
the fixed-up filename, and returns True to use the fixed-up file,
false to not use it.
If |perform_safety_checks| is True, then the function checks whether it is
unsafe to reorder headers in this file and skips the reorder with a warning
message in that case.
"""
if perform_safety_checks and IsUnsafeToReorderHeaders(filename):
print ('Not reordering headers in %s as the script thinks that the '
'order of headers in this file is semantically significant.'
% (filename))
return
fixfilename = filename + '.new'
infile = open(filename, 'rb')
outfile = open(fixfilename, 'wb')
SortHeader(infile, outfile, for_blink)
infile.close()
outfile.close() # Important so the below diff gets the updated contents.
try:
if confirm_function(filename, fixfilename):
if sys.platform == 'win32':
os.unlink(filename)
os.rename(fixfilename, filename)
finally:
try:
os.remove(fixfilename)
except OSError:
# If the file isn't there, we don't care.
pass
def DiffAndConfirm(filename, should_confirm, perform_safety_checks, for_blink):
"""Shows a diff of what the tool would change the file named
filename to. Shows a confirmation prompt if should_confirm is true.
Saves the resulting file if should_confirm is false or the user
answers Y to the confirmation prompt.
"""
def ConfirmFunction(filename, fixfilename):
diff = os.system('diff -u %s %s' % (filename, fixfilename))
if sys.platform != 'win32':
diff >>= 8
if diff == 0: # Check exit code.
print '%s: no change' % filename
return False
return (not should_confirm or YesNo('Use new file (y/N)?'))
FixFileWithConfirmFunction(filename, ConfirmFunction, perform_safety_checks,
for_blink)
def IsUnsafeToReorderHeaders(filename):
# *_message_generator.cc is almost certainly a file that generates IPC
# definitions. Changes in include order in these files can result in them not
# building correctly.
if filename.find("message_generator.cc") != -1:
return True
return False
def main():
parser = optparse.OptionParser(usage='%prog filename1 filename2 ...')
parser.add_option('-f', '--force', action='store_false', default=True,
dest='should_confirm',
help='Turn off confirmation prompt.')
parser.add_option('--no_safety_checks',
action='store_false', default=True,
dest='perform_safety_checks',
help='Do not perform the safety checks via which this '
'script refuses to operate on files for which it thinks '
'the include ordering is semantically significant.')
parser.add_option('--for_blink', action='store_true', default=False,
dest='for_blink', help='Whether the blink header sorting '
'rules should be applied.')
opts, filenames = parser.parse_args()
if len(filenames) < 1:
parser.print_help()
return 1
for filename in filenames:
DiffAndConfirm(filename, opts.should_confirm, opts.perform_safety_checks,
opts.for_blink)
if __name__ == '__main__':
sys.exit(main())