~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2005, 2006 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

"""Commit message editor support."""

import codecs

import errno

import os

from subprocess import call

import sys

from bzrlib import (

    config,

    osutils,

    trace,

    )

from bzrlib.errors import BzrError, BadCommitMessageEncoding

from bzrlib.hooks import HookPoint, Hooks

def _get_editor():

    """Return a sequence of possible editor binaries for the current platform"""

    try:

        yield os.environ["BZR_EDITOR"], '$BZR_EDITOR'

    except KeyError:

        pass

    e = config.GlobalConfig().get_editor()

    if e is not None:

        yield e, config.config_filename()

    for varname in 'VISUAL', 'EDITOR':

        if varname in os.environ:

            yield os.environ[varname], '$' + varname

    if sys.platform == 'win32':

        for editor in 'wordpad.exe', 'notepad.exe':

            yield editor, None

    else:

        for editor in ['/usr/bin/editor', 'vi', 'pico', 'nano', 'joe']:

            yield editor, None

def _run_editor(filename):

    """Try to execute an editor to edit the commit message."""

    for candidate, candidate_source in _get_editor():

        edargs = candidate.split(' ')

        try:

            ## mutter("trying editor: %r", (edargs +[filename]))

            x = call(edargs + [filename])

        except OSError, e:

            # We're searching for an editor, so catch safe errors and continue

            # errno 193 is ERROR_BAD_EXE_FORMAT on Windows. Python2.4 uses the

            # winerror for errno. Python2.5+ use errno ENOEXEC and set winerror

            # to 193. However, catching 193 here should be fine. Other

            # platforms aren't likely to have that high of an error. And even

            # if they do, it is still reasonable to fall back to the next

            # editor.

            if e.errno in (errno.ENOENT, errno.EACCES, errno.ENOEXEC, 193):

                if candidate_source is not None:

                    # We tried this editor because some user configuration (an

                    # environment variable or config file) said to try it.  Let

                    # the user know their configuration is broken.

                    trace.warning(

                        'Could not start editor "%s" (specified by %s): %s\n'

                        % (candidate, candidate_source, str(e)))

                continue

            raise

        if x == 0:

            return True

        elif x == 127:

            continue

        else:

            break

    raise BzrError("Could not start any editor.\nPlease specify one with:\n"

                   " - $BZR_EDITOR\n - editor=/some/path in %s\n"

                   " - $VISUAL\n - $EDITOR" % \

                    config.config_filename())

DEFAULT_IGNORE_LINE = "%(bar)s %(msg)s %(bar)s" % \

    { 'bar' : '-' * 14, 'msg' : 'This line and the following will be ignored' }

def edit_commit_message(infotext, ignoreline=DEFAULT_IGNORE_LINE,

                        start_message=None):

    """Let the user edit a commit message in a temp file.

    This is run if they don't give a message or

    message-containing file on the command line.

    :param infotext:    Text to be displayed at bottom of message

                        for the user's reference;

                        currently similar to 'bzr status'.

    :param ignoreline:  The separator to use above the infotext.

    :param start_message:   The text to place above the separator, if any.

                            This will not be removed from the message

                            after the user has edited it.

    :return:    commit message or None.

    """

    if not start_message is None:

        start_message = start_message.encode(osutils.get_user_encoding())

    infotext = infotext.encode(osutils.get_user_encoding(), 'replace')

    return edit_commit_message_encoded(infotext, ignoreline, start_message)

def edit_commit_message_encoded(infotext, ignoreline=DEFAULT_IGNORE_LINE,

                                start_message=None):

    """Let the user edit a commit message in a temp file.

    This is run if they don't give a message or

    message-containing file on the command line.

    :param infotext:    Text to be displayed at bottom of message

                        for the user's reference;

                        currently similar to 'bzr status'.

                        The string is already encoded

    :param ignoreline:  The separator to use above the infotext.

    :param start_message:   The text to place above the separator, if any.

                            This will not be removed from the message

                            after the user has edited it.

                            The string is already encoded

    :return:    commit message or None.

    """

    msgfilename = None

    try:

        msgfilename, hasinfo = _create_temp_file_with_commit_template(

                                    infotext, ignoreline, start_message)

        if not msgfilename or not _run_editor(msgfilename):

            return None

        started = False

        msg = []

        lastline, nlines = 0, 0

        # codecs.open() ALWAYS opens file in binary mode but we need text mode

        # 'rU' mode useful when bzr.exe used on Cygwin (bialix 20070430)

        f = file(msgfilename, 'rU')

        try:

            try:

                for line in codecs.getreader(osutils.get_user_encoding())(f):

                    stripped_line = line.strip()

                    # strip empty line before the log message starts

                    if not started:

                        if stripped_line != "":

                            started = True

                        else:

                            continue

                    # check for the ignore line only if there

                    # is additional information at the end

                    if hasinfo and stripped_line == ignoreline:

                        break

                    nlines += 1

                    # keep track of the last line that had some content

                    if stripped_line != "":

                        lastline = nlines

                    msg.append(line)

            except UnicodeDecodeError:

                raise BadCommitMessageEncoding()

        finally:

            f.close()

        if len(msg) == 0:

            return ""

        # delete empty lines at the end

        del msg[lastline:]

        # add a newline at the end, if needed

        if not msg[-1].endswith("\n"):

            return "%s%s" % ("".join(msg), "\n")

        else:

            return "".join(msg)

    finally:

        # delete the msg file in any case

        if msgfilename is not None:

            try:

                os.unlink(msgfilename)

            except IOError, e:

                trace.warning(

                    "failed to unlink %s: %s; ignored", msgfilename, e)

def _create_temp_file_with_commit_template(infotext,

                                           ignoreline=DEFAULT_IGNORE_LINE,

                                           start_message=None):

    """Create temp file and write commit template in it.

    :param infotext:    Text to be displayed at bottom of message

                        for the user's reference;

                        currently similar to 'bzr status'.

                        The text is already encoded.

    :param ignoreline:  The separator to use above the infotext.

    :param start_message:   The text to place above the separator, if any.

                            This will not be removed from the message

                            after the user has edited it.

                            The string is already encoded

    :return:    2-tuple (temp file name, hasinfo)

    """

    import tempfile

    tmp_fileno, msgfilename = tempfile.mkstemp(prefix='bzr_log.',

                                               dir='.',

                                               text=True)

    msgfilename = osutils.basename(msgfilename)

    msgfile = os.fdopen(tmp_fileno, 'w')

    try:

        if start_message is not None:

            msgfile.write("%s\n" % start_message)

        if infotext is not None and infotext != "":

            hasinfo = True

            msgfile.write("\n\n%s\n\n%s" %(ignoreline, infotext))

        else:

            hasinfo = False

    finally:

        msgfile.close()

    return (msgfilename, hasinfo)

def make_commit_message_template(working_tree, specific_files):

    """Prepare a template file for a commit into a branch.

    Returns a unicode string containing the template.

    """

    # TODO: make provision for this to be overridden or modified by a hook

    #

    # TODO: Rather than running the status command, should prepare a draft of

    # the revision to be committed, then pause and ask the user to

    # confirm/write a message.

    from StringIO import StringIO       # must be unicode-safe

    from bzrlib.status import show_tree_status

    status_tmp = StringIO()

    show_tree_status(working_tree, specific_files=specific_files,

                     to_file=status_tmp, verbose=True)

    return status_tmp.getvalue()

def make_commit_message_template_encoded(working_tree, specific_files,

                                         diff=None, output_encoding='utf-8'):

    """Prepare a template file for a commit into a branch.

    Returns an encoded string.

    """

    # TODO: make provision for this to be overridden or modified by a hook

    #

    # TODO: Rather than running the status command, should prepare a draft of

    # the revision to be committed, then pause and ask the user to

    # confirm/write a message.

    from StringIO import StringIO       # must be unicode-safe

    from bzrlib.diff import show_diff_trees

    template = make_commit_message_template(working_tree, specific_files)

    template = template.encode(output_encoding, "replace")

    if diff:

        stream = StringIO()

        show_diff_trees(working_tree.basis_tree(),

                        working_tree, stream, specific_files,

                        path_encoding=output_encoding)

        template = template + '\n' + stream.getvalue()

    return template

class MessageEditorHooks(Hooks):

    """A dictionary mapping hook name to a list of callables for message editor

    hooks.

    e.g. ['commit_message_template'] is the list of items to be called to

    generate a commit message template

    """

    def __init__(self):

        """Create the default hooks.

        These are all empty initially.

        """

        Hooks.__init__(self)

        self.create_hook(HookPoint('commit_message_template',

            "Called when a commit message is being generated. "

            "commit_message_template is called with the bzrlib.commit.Commit "

            "object and the message that is known so far. "

            "commit_message_template must return a new message to use (which "

            "could be the same as it was given. When there are multiple "

            "hooks registered for commit_message_template, they are chained "

            "with the result from the first passed into the second, and so "

            "on.", (1, 10), None))

hooks = MessageEditorHooks()

def generate_commit_message_template(commit, start_message=None):

    """Generate a commit message template.

    :param commit: Commit object for the active commit.

    :param start_message: Message to start with.

    :return: A start commit message or None for an empty start commit message.

    """

    start_message = None

    for hook in hooks['commit_message_template']:

        start_message = hook(commit, start_message)

    return start_message