third_party/WebKit/Tools/Scripts/webkitpy/style/patchreader.py

# Copyright (C) 2010 Google Inc. All rights reserved.
# Copyright (C) 2010 Chris Jerdonek (chris.jerdonek@gmail.com)
# Copyright (C) 2010 ProFUSION embedded systems
#
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import logging

from webkitpy.common.checkout.diff_parser import DiffParser


_log = logging.getLogger(__name__)


class PatchReader(object):
    """Supports checking style in patches."""

    def __init__(self, text_file_reader):
        """Create a PatchReader instance.

        Args:
          text_file_reader: A TextFileReader instance.
        """
        self._text_file_reader = text_file_reader

    def check(self, patch_string):
        """Checks style in the given patch."""
        patch_files = DiffParser(patch_string.splitlines()).files

        for path, diff_file in patch_files.iteritems():
            line_numbers = diff_file.added_or_modified_line_numbers()
            _log.debug('Found %s new or modified lines in: %s', len(line_numbers), path)

            if not line_numbers:
                # Don't check files which contain only deleted lines
                # as they can never add style errors. However, mark them as
                # processed so that we count up number of such files.
                self._text_file_reader.count_delete_only_file()
                continue

            self._text_file_reader.process_file(file_path=path, line_numbers=line_numbers)