/brz/remove-bazaar

# Copyright (C) 2008 Canonical Ltd

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

"""The python implementation of chunks_to_lines"""

def chunks_to_lines(chunks):

    """Re-split chunks into simple lines.

    Each entry in the result should contain a single newline at the end. Except

    for the last entry which may not have a final newline. If chunks is already

    a simple list of lines, we return it directly.

    :param chunks: An list/tuple of strings. If chunks is already a list of

        lines, then we will return it as-is.

    :return: A list of strings.

    """

    # Optimize for a very common case when chunks are already lines

    last_no_newline = False

    for chunk in chunks:

        if last_no_newline:

            # Only the last chunk is allowed to not have a trailing newline

            # Getting here means the last chunk didn't have a newline, and we

            # have a chunk following it

            break

        if not chunk:

            # Empty strings are never valid lines

            break

        elif b'\n' in chunk[:-1]:

            # This chunk has an extra '\n', so we will have to split it

            break

        elif chunk[-1:] != b'\n':

            # This chunk does not have a trailing newline

            last_no_newline = True

    else:

        # All of the lines (but possibly the last) have a single newline at the

        # end of the string.

        # For the last one, we allow it to not have a trailing newline, but it

        # is not allowed to be an empty string.

        return chunks

    # These aren't simple lines, just join and split again.

    from breezy import osutils

    return osutils._split_lines(b''.join(chunks))