def apply_patch(self, patch_file, base_path, base_dir, p=None,
                    revert=False):
        """Apply the patch and return a PatchResult indicating its success."""
        if not is_valid_version(self.subversion_client_version,
                                self.PATCH_MIN_VERSION):
            raise MinimumVersionError(
                'Using "rbt patch" with the SVN backend requires at least '
                'svn 1.7.0')

        if base_dir and not base_dir.startswith(base_path):
            # The patch was created in either a higher level directory or a
            # directory not under this one. We should exclude files from the
            # patch that are not under this directory.
            excluded, empty = self._exclude_files_not_in_tree(patch_file,
                                                              base_path)

            if excluded:
                logging.warn('This patch was generated in a different '
                             'directory. To prevent conflicts, all files '
                             'not under the current directory have been '
                             'excluded. To apply all files in this '
                             'patch, apply this patch from the %s directory.'
                             % base_dir)

                if empty:
                    logging.warn('All files were excluded from the patch.')

        cmd = ['patch']
        p_num = p or self._get_p_number(base_path, base_dir)

        if p_num >= 0:
            cmd.append('--strip=%s' % p_num)

        if revert:
            cmd.append('--reverse-diff')

        cmd.append(six.text_type(patch_file))

        rc, patch_output = self._run_svn(cmd, return_error_code=True)

        if self.supports_empty_files():
            try:
                with open(patch_file, 'rb') as f:
                    patch = f.read()
            except __HOLE__ as e:
                logging.error('Unable to read file %s: %s', patch_file, e)
                return

            self.apply_patch_for_empty_files(patch, p_num, revert=revert)

            # TODO: What is svn's equivalent of a garbage patch message?

        return PatchResult(applied=(rc == 0), patch_output=patch_output)
dataset/ETHPy150Open reviewboard/rbtools/rbtools/clients/svn.py/SVNClient.apply_patch