#!/usr/bin/python##  Copyright (c) 2012 The WebM project authors. All Rights Reserved.####  Use of this source code is governed by a BSD-style license##  that can be found in the LICENSE file in the root of the source##  tree. An additional intellectual property rights grant can be found##  in the file PATENTS.  All contributing project authors may##  be found in the AUTHORS file in the root of the source tree.##"""Performs style checking on each diff hunk."""import getoptimport osimport StringIOimport subprocessimport sys import diff  SHORT_OPTIONS = "h"LONG_OPTIONS = ["help"] TOPLEVEL_CMD = ["git", "rev-parse", "--show-toplevel"]DIFF_CMD = ["git", "diff"]DIFF_INDEX_CMD = ["git", "diff-index", "-u", "HEAD", "--"]SHOW_CMD = ["git", "show"]CPPLINT_FILTERS = ["-readability/casting"]  class Usage(Exception):    pass  class SubprocessException(Exception):    def __init__(self, args):        msg = "Failed to execute '%s'"%(" ".join(args))        super(SubprocessException, self).__init__(msg)  class Subprocess(subprocess.Popen):    """Adds the notion of an expected returncode to Popen."""     def __init__(self, args, expected_returncode=0, **kwargs):        self._args = args        self._expected_returncode = expected_returncode        super(Subprocess, self).__init__(args, **kwargs)     def communicate(self, *args, **kwargs):        result = super(Subprocess, self).communicate(*args, **kwargs)        if self._expected_returncode is not None:            try:                ok = self.returncode in self._expected_returncode            except TypeError:                ok = self.returncode == self._expected_returncode            if not ok:                raise SubprocessException(self._args)        return result  def main(argv=None):    if argv is None:        argv = sys.argv    try:        try:            opts, args = getopt.getopt(argv[1:], SHORT_OPTIONS, LONG_OPTIONS)        except getopt.error, msg:            raise Usage(msg)         # process options        for o, _ in opts:            if o in ("-h", "--help"):                print __doc__                sys.exit(0)         if args and len(args) > 1:            print __doc__            sys.exit(0)         # Find the fully qualified path to the root of the tree        tl = Subprocess(TOPLEVEL_CMD, stdout=subprocess.PIPE)        tl = tl.communicate()[0].strip()         # See if we're working on the index or not.        if args:            diff_cmd = DIFF_CMD + [args[0] + "^!"]        else:            diff_cmd = DIFF_INDEX_CMD         # Build the command line to execute cpplint        cpplint_cmd = [os.path.join(tl, "tools", "cpplint.py"),                       "--filter=" + ",".join(CPPLINT_FILTERS),                       "-"]         # Get a list of all affected lines        file_affected_line_map = {}        p = Subprocess(diff_cmd, stdout=subprocess.PIPE)        stdout = p.communicate()[0]        for hunk in diff.ParseDiffHunks(StringIO.StringIO(stdout)):            filename = hunk.right.filename[2:]            if filename not in file_affected_line_map:                file_affected_line_map[filename] = set()            file_affected_line_map[filename].update(hunk.right.delta_line_nums)         # Run each affected file through cpplint        lint_failed = False        for filename, affected_lines in file_affected_line_map.iteritems():            if filename.split(".")[-1] not in ("c", "h", "cc"):                continue            if filename.startswith("third_party"):                continue             if args:                # File contents come from git                show_cmd = SHOW_CMD + [args[0] + ":" + filename]                show = Subprocess(show_cmd, stdout=subprocess.PIPE)                lint = Subprocess(cpplint_cmd, expected_returncode=(0, 1),                                  stdin=show.stdout, stderr=subprocess.PIPE)                lint_out = lint.communicate()[1]            else:                # File contents come from the working tree                lint = Subprocess(cpplint_cmd, expected_returncode=(0, 1),                                  stdin=subprocess.PIPE, stderr=subprocess.PIPE)                stdin = open(os.path.join(tl, filename)).read()                lint_out = lint.communicate(stdin)[1]             for line in lint_out.split("\n"):                fields = line.split(":")                if fields[0] != "-":                    continue                warning_line_num = int(fields[1])                if warning_line_num in affected_lines:                    print "%s:%d:%s"%(filename, warning_line_num,                                      ":".join(fields[2:]))                    lint_failed = True         # Set exit code if any relevant lint errors seen        if lint_failed:            return 1     except Usage, err:        print >>sys.stderr, err        print >>sys.stderr, "for help use --help"        return 2 if __name__ == "__main__":    sys.exit(main())