tools/lint-hunks.py

   1 #!/usr/bin/python
   2 ##  Copyright (c) 2012 The WebM project authors. All Rights Reserved.
   3 ##
   4 ##  Use of this source code is governed by a BSD-style license
   5 ##  that can be found in the LICENSE file in the root of the source
   6 ##  tree. An additional intellectual property rights grant can be found
   7 ##  in the file PATENTS.  All contributing project authors may
   8 ##  be found in the AUTHORS file in the root of the source tree.
   9 ##
  10 """Performs style checking on each diff hunk."""
  11 import getopt
  12 import os
  13 import StringIO
  14 import subprocess
  15 import sys
  16
  17 import diff
  18
  19
  20 SHORT_OPTIONS = "h"
  21 LONG_OPTIONS = ["help"]
  22
  23 TOPLEVEL_CMD = ["git", "rev-parse", "--show-toplevel"]
  24 DIFF_CMD = ["git", "diff"]
  25 DIFF_INDEX_CMD = ["git", "diff-index", "-u", "HEAD", "--"]
  26 SHOW_CMD = ["git", "show"]
  27 CPPLINT_FILTERS = ["-readability/casting"]
  28
  29
  30 class Usage(Exception):
  31     pass
  32
  33
  34 class SubprocessException(Exception):
  35     def __init__(self, args):
  36         msg = "Failed to execute '%s'"%(" ".join(args))
  37         super(SubprocessException, self).__init__(msg)
  38
  39
  40 class Subprocess(subprocess.Popen):
  41     """Adds the notion of an expected returncode to Popen."""
  42
  43     def __init__(self, args, expected_returncode=0, **kwargs):
  44         self._args = args
  45         self._expected_returncode = expected_returncode
  46         super(Subprocess, self).__init__(args, **kwargs)
  47
  48     def communicate(self, *args, **kwargs):
  49         result = super(Subprocess, self).communicate(*args, **kwargs)
  50         if self._expected_returncode is not None:
  51             try:
  52                 ok = self.returncode in self._expected_returncode
  53             except TypeError:
  54                 ok = self.returncode == self._expected_returncode
  55             if not ok:
  56                 raise SubprocessException(self._args)
  57         return result
  58
  59
  60 def main(argv=None):
  61     if argv is None:
  62         argv = sys.argv
  63     try:
  64         try:
  65             opts, args = getopt.getopt(argv[1:], SHORT_OPTIONS, LONG_OPTIONS)
  66         except getopt.error, msg:
  67             raise Usage(msg)
  68
  69         # process options
  70         for o, _ in opts:
  71             if o in ("-h", "--help"):
  72                 print __doc__
  73                 sys.exit(0)
  74
  75         if args and len(args) > 1:
  76             print __doc__
  77             sys.exit(0)
  78
  79         # Find the fully qualified path to the root of the tree
  80         tl = Subprocess(TOPLEVEL_CMD, stdout=subprocess.PIPE)
  81         tl = tl.communicate()[0].strip()
  82
  83         # See if we're working on the index or not.
  84         if args:
  85             diff_cmd = DIFF_CMD + [args[0] + "^!"]
  86         else:
  87             diff_cmd = DIFF_INDEX_CMD
  88
  89         # Build the command line to execute cpplint
  90         cpplint_cmd = [os.path.join(tl, "tools", "cpplint.py"),
  91                        "--filter=" + ",".join(CPPLINT_FILTERS),
  92                        "-"]
  93
  94         # Get a list of all affected lines
  95         file_affected_line_map = {}
  96         p = Subprocess(diff_cmd, stdout=subprocess.PIPE)
  97         stdout = p.communicate()[0]
  98         for hunk in diff.ParseDiffHunks(StringIO.StringIO(stdout)):
  99             filename = hunk.right.filename[2:]
 100             if filename not in file_affected_line_map:
 101                 file_affected_line_map[filename] = set()
 102             file_affected_line_map[filename].update(hunk.right.delta_line_nums)
 103
 104         # Run each affected file through cpplint
 105         lint_failed = False
 106         for filename, affected_lines in file_affected_line_map.iteritems():
 107             if filename.split(".")[-1] not in ("c", "h", "cc"):
 108                 continue
 109
 110             if args:
 111                 # File contents come from git
 112                 show_cmd = SHOW_CMD + [args[0] + ":" + filename]
 113                 show = Subprocess(show_cmd, stdout=subprocess.PIPE)
 114                 lint = Subprocess(cpplint_cmd, expected_returncode=(0, 1),
 115                                   stdin=show.stdout, stderr=subprocess.PIPE)
 116                 lint_out = lint.communicate()[1]
 117             else:
 118                 # File contents come from the working tree
 119                 lint = Subprocess(cpplint_cmd, expected_returncode=(0, 1),
 120                                   stdin=subprocess.PIPE, stderr=subprocess.PIPE)
 121                 stdin = open(os.path.join(tl, filename)).read()
 122                 lint_out = lint.communicate(stdin)[1]
 123
 124             for line in lint_out.split("\n"):
 125                 fields = line.split(":")
 126                 if fields[0] != "-":
 127                     continue
 128                 warning_line_num = int(fields[1])
 129                 if warning_line_num in affected_lines:
 130                     print "%s:%d:%s"%(filename, warning_line_num,
 131                                       ":".join(fields[2:]))
 132                     lint_failed = True
 133
 134         # Set exit code if any relevant lint errors seen
 135         if lint_failed:
 136             return 1
 137
 138     except Usage, err:
 139         print >>sys.stderr, err
 140         print >>sys.stderr, "for help use --help"
 141         return 2
 142
 143 if __name__ == "__main__":
 144     sys.exit(main())