/brz/remove-bazaar

To get this branch, use:
bzr branch http://gegoxaren.bato24.eu/bzr/brz/remove-bazaar
2052.3.2 by John Arbash Meinel
Change Copyright .. by Canonical to Copyright ... Canonical
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# Copyright (C) 2005 Canonical Ltd
1185.47.1 by Martin Pool
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#
2052.3.1 by John Arbash Meinel
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
4183.7.1 by Sabin Iacob
update FSF mailing address
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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6379.6.3 by Jelmer Vernooij
Use absolute_import.
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from __future__ import absolute_import
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1185.47.1 by Martin Pool
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# \subsection{\emph{rio} - simple text metaformat}
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#
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# \emph{r} stands for `restricted', `reproducible', or `rfc822-like'.
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#
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# The stored data consists of a series of \emph{stanzas}, each of which contains
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# \emph{fields} identified by an ascii name, with Unicode or string contents.
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# The field tag is constrained to alphanumeric characters.
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# There may be more than one field in a stanza with the same name.
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#
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# The format itself does not deal with character encoding issues, though
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# the result will normally be written in Unicode.
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#
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# The format is intended to be simple enough that there is exactly one character
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# stream representation of an object and vice versa, and that this relation
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# will continue to hold for future versions of bzr.
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import re
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6624 by Jelmer Vernooij
Merge Python3 porting work ('py3 pokes')
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from . import osutils
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from .iterablefile import IterableFile
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from .sixish import (
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    text_type,
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    )
1534.10.2 by Aaron Bentley
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1185.47.1 by Martin Pool
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# XXX: some redundancy is allowing to write stanzas in isolation as well as
3943.8.1 by Marius Kruger
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# through a writer object.
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7143.15.2 by Jelmer Vernooij
Run autopep8.
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1185.47.1 by Martin Pool
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class RioWriter(object):
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    def __init__(self, to_file):
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        self._soft_nl = False
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        self._to_file = to_file
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    def write_stanza(self, stanza):
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        if self._soft_nl:
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            self._to_file.write(b'\n')
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        stanza.write(self._to_file)
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        self._soft_nl = True
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class RioReader(object):
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    """Read stanzas from a file as a sequence
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    to_file can be anything that can be enumerated as a sequence of
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    lines (with newlines.)
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    """
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Run autopep8.
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    def __init__(self, from_file):
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        self._from_file = from_file
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    def __iter__(self):
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        while True:
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            s = read_stanza(self._from_file)
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            if s is None:
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                break
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            else:
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                yield s
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1534.10.2 by Aaron Bentley
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def rio_file(stanzas, header=None):
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    """Produce a rio IterableFile from an iterable of stanzas"""
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    def str_iter():
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        if header is not None:
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            yield header + b'\n'
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        first_stanza = True
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        for s in stanzas:
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            if first_stanza is not True:
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                yield b'\n'
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            for line in s.to_lines():
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                yield line
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            first_stanza = False
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    return IterableFile(str_iter())
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def read_stanzas(from_file):
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    while True:
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        s = read_stanza(from_file)
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        if s is None:
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            break
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Review comments & test fixes.
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        yield s
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def read_stanzas_unicode(from_file):
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    while True:
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        s = read_stanza_unicode(from_file)
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        if s is None:
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            break
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        yield s
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class Stanza(object):
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    """One stanza for rio.
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    Each stanza contains a set of named fields.
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    Names must be non-empty ascii alphanumeric plus _.  Names can be repeated
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    within a stanza.  Names are case-sensitive.  The ordering of fields is
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    preserved.
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    Each field value must be either an int or a string.
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    """
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    __slots__ = ['items']
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    def __init__(self, **kwargs):
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        """Construct a new Stanza.
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        The keyword arguments, if any, are added in sorted order to the stanza.
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        """
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        self.items = []
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        if kwargs:
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            for tag, value in sorted(kwargs.items()):
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                self.add(tag, value)
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    def add(self, tag, value):
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        """Append a name and value to the stanza."""
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        if not valid_tag(tag):
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            raise ValueError("invalid tag %r" % (tag,))
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        if isinstance(value, bytes):
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            value = value.decode('ascii')
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        elif isinstance(value, text_type):
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            pass
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        else:
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rio.Stanza.add should raise TypeError on invalid types.
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            raise TypeError("invalid type for rio value: %r of type %s"
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                            % (value, type(value)))
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        self.items.append((tag, value))
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    @classmethod
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    def from_pairs(cls, pairs):
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        ret = cls()
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        ret.items = pairs
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        return ret
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    def __contains__(self, find_tag):
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        """True if there is any field in this stanza with the given tag."""
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        for tag, value in self.items:
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            if tag == find_tag:
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                return True
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        return False
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    def __len__(self):
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        """Return number of pairs in the stanza."""
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        return len(self.items)
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    def __eq__(self, other):
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        if not isinstance(other, Stanza):
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            return False
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        return self.items == other.items
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    def __ne__(self, other):
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        return not self.__eq__(other)
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    def __repr__(self):
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        return "Stanza(%r)" % self.items
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    def iter_pairs(self):
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        """Return iterator of tag, value pairs."""
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        return iter(self.items)
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    def to_lines(self):
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        """Generate sequence of lines for external version of this file.
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1553.5.32 by Martin Pool
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        The lines are always utf-8 encoded strings.
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        """
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        if not self.items:
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            # max() complains if sequence is empty
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            return []
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        result = []
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        for text_tag, text_value in self.items:
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            tag = text_tag.encode('ascii')
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            value = text_value.encode('utf-8')
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            if value == b'':
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                result.append(tag + b': \n')
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            elif b'\n' in value:
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                # don't want splitlines behaviour on empty lines
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                val_lines = value.split(b'\n')
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                result.append(tag + b': ' + val_lines[0] + b'\n')
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                for line in val_lines[1:]:
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                    result.append(b'\t' + line + b'\n')
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            else:
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                result.append(tag + b': ' + value + b'\n')
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        return result
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    def to_string(self):
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        """Return stanza as a single string"""
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        return b''.join(self.to_lines())
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2030.1.1 by John Arbash Meinel
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    def to_unicode(self):
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        """Return stanza as a single Unicode string.
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        This is most useful when adding a Stanza to a parent Stanza
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        """
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        if not self.items:
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            return u''
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        result = []
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        for tag, value in self.items:
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            if value == u'':
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                result.append(tag + u': \n')
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            elif u'\n' in value:
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                # don't want splitlines behaviour on empty lines
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                val_lines = value.split(u'\n')
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                result.append(tag + u': ' + val_lines[0] + u'\n')
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                for line in val_lines[1:]:
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More performance tweaks.
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                    result.append(u'\t' + line + u'\n')
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            else:
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More performance tweaks.
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                result.append(tag + u': ' + value + u'\n')
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        return u''.join(result)
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1185.47.1 by Martin Pool
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    def write(self, to_file):
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        """Write stanza to a file"""
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        to_file.writelines(self.to_lines())
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    def get(self, tag):
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        """Return the value for a field wih given tag.
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        If there is more than one value, only the first is returned.  If the
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        tag is not present, KeyError is raised.
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        """
241
        for t, v in self.items:
242
            if t == tag:
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                return v
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        else:
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            raise KeyError(tag)
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    __getitem__ = get
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    def get_all(self, tag):
250
        r = []
251
        for t, v in self.items:
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            if t == tag:
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                r.append(v)
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        return r
1553.5.8 by Martin Pool
New Rio.as_dict method
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    def as_dict(self):
257
        """Return a dict containing the unique values of the stanza.
258
        """
259
        d = {}
260
        for tag, value in self.items:
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            d[tag] = value
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        return d
3943.8.1 by Marius Kruger
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4354.3.1 by Jelmer Vernooij
Move core RIO parsing functionality to _rio_py.py.
264
1185.47.1 by Martin Pool
[broken] start converting basic_io to more rfc822-like format
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def valid_tag(tag):
4354.3.1 by Jelmer Vernooij
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    return _valid_tag(tag)
1185.47.1 by Martin Pool
[broken] start converting basic_io to more rfc822-like format
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def read_stanza(line_iter):
270
    """Return new Stanza read from list of lines or a file
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1185.47.1 by Martin Pool
[broken] start converting basic_io to more rfc822-like format
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    Returns one Stanza that was read, or returns None at end of file.  If a
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    blank line follows the stanza, it is consumed.  It's not an error for
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    there to be no blank at end of file.  If there is a blank file at the
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    start of the input this is really an empty stanza and that is returned.
1185.47.2 by Martin Pool
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277
    Only the stanza lines and the trailing blank (if any) are consumed
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    from the line_iter.
1553.5.32 by Martin Pool
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    The raw lines must be in utf-8 encoding.
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[broken] start converting basic_io to more rfc822-like format
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    """
4354.3.1 by Jelmer Vernooij
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282
    return _read_stanza_utf8(line_iter)
2030.1.5 by John Arbash Meinel
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def read_stanza_unicode(unicode_iter):
286
    """Read a Stanza from a list of lines or a file.
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288
    The lines should already be in unicode form. This returns a single
289
    stanza that was read. If there is a blank line at the end of the Stanza,
290
    it is consumed. It is not an error for there to be no blank line at
291
    the end of the iterable. If there is a blank line at the beginning,
292
    this is treated as an empty Stanza and None is returned.
293
294
    Only the stanza lines and the trailing blank (if any) are consumed
295
    from the unicode_iter
296
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    :param unicode_iter: A iterable, yeilding Unicode strings. See read_stanza
298
        if you have a utf-8 encoded string.
299
    :return: A Stanza object if there are any lines in the file.
300
        None otherwise
301
    """
4354.3.1 by Jelmer Vernooij
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302
    return _read_stanza_unicode(unicode_iter)
1551.12.38 by Aaron Bentley
Add docs for MergeDirective and RIO-patch functions
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1551.12.10 by Aaron Bentley
Reduce max width to 72
305
def to_patch_lines(stanza, max_width=72):
1551.12.38 by Aaron Bentley
Add docs for MergeDirective and RIO-patch functions
306
    """Convert a stanza into RIO-Patch format lines.
307
308
    RIO-Patch is a RIO variant designed to be e-mailed as part of a patch.
309
    It resists common forms of damage such as newline conversion or the removal
310
    of trailing whitespace, yet is also reasonably easy to read.
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    :param max_width: The maximum number of characters per physical line.
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    :return: a list of lines
314
    """
3376.2.4 by Martin Pool
Remove every assert statement from bzrlib!
315
    if max_width <= 6:
316
        raise ValueError(max_width)
1551.12.10 by Aaron Bentley
Reduce max width to 72
317
    max_rio_width = max_width - 4
1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
318
    lines = []
319
    for pline in stanza.to_lines():
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
320
        for line in pline.split(b'\n')[:-1]:
321
            line = re.sub(b'\\\\', b'\\\\\\\\', line)
1551.12.9 by Aaron Bentley
force patch-rio to 76 characters
322
            while len(line) > 0:
1551.12.10 by Aaron Bentley
Reduce max width to 72
323
                partline = line[:max_rio_width]
324
                line = line[max_rio_width:]
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
325
                if len(line) > 0 and line[:1] != [b' ']:
1551.12.21 by Aaron Bentley
Patch-RIO does line breaks in slightly more readable places
326
                    break_index = -1
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
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                    break_index = partline.rfind(b' ', -20)
1551.12.23 by Aaron Bentley
Indent line continuations in Patch-RIO, to improve readability
328
                    if break_index < 3:
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
329
                        break_index = partline.rfind(b'-', -20)
1551.12.21 by Aaron Bentley
Patch-RIO does line breaks in slightly more readable places
330
                        break_index += 1
1551.12.23 by Aaron Bentley
Indent line continuations in Patch-RIO, to improve readability
331
                    if break_index < 3:
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
332
                        break_index = partline.rfind(b'/', -20)
1551.12.23 by Aaron Bentley
Indent line continuations in Patch-RIO, to improve readability
333
                    if break_index >= 3:
1551.12.21 by Aaron Bentley
Patch-RIO does line breaks in slightly more readable places
334
                        line = partline[break_index:] + line
335
                        partline = partline[:break_index]
1551.12.23 by Aaron Bentley
Indent line continuations in Patch-RIO, to improve readability
336
                if len(line) > 0:
6684.1.6 by Martin
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                    line = b'  ' + line
338
                partline = re.sub(b'\r', b'\\\\r', partline)
1551.12.11 by Aaron Bentley
Handle trailing whitepace cleanly
339
                blank_line = False
1551.12.9 by Aaron Bentley
force patch-rio to 76 characters
340
                if len(line) > 0:
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
341
                    partline += b'\\'
342
                elif re.search(b' $', partline):
343
                    partline += b'\\'
1551.12.11 by Aaron Bentley
Handle trailing whitepace cleanly
344
                    blank_line = True
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
345
                lines.append(b'# ' + partline + b'\n')
1551.12.11 by Aaron Bentley
Handle trailing whitepace cleanly
346
                if blank_line:
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
347
                    lines.append(b'#   \n')
1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
348
    return lines
349
1551.12.23 by Aaron Bentley
Indent line continuations in Patch-RIO, to improve readability
350
1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
351
def _patch_stanza_iter(line_iter):
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
352
    map = {b'\\\\': b'\\',
7143.15.2 by Jelmer Vernooij
Run autopep8.
353
           b'\\r': b'\r',
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
354
           b'\\\n': b''}
7143.15.2 by Jelmer Vernooij
Run autopep8.
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1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
356
    def mapget(match):
357
        return map[match.group(0)]
358
1551.12.9 by Aaron Bentley
force patch-rio to 76 characters
359
    last_line = None
1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
360
    for line in line_iter:
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
361
        if line.startswith(b'# '):
1551.12.22 by Aaron Bentley
Fix handling of whitespace-stripping without newline munging
362
            line = line[2:]
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
363
        elif line.startswith(b'#'):
1551.12.22 by Aaron Bentley
Fix handling of whitespace-stripping without newline munging
364
            line = line[1:]
3376.2.4 by Martin Pool
Remove every assert statement from bzrlib!
365
        else:
366
            raise ValueError("bad line %r" % (line,))
1551.12.23 by Aaron Bentley
Indent line continuations in Patch-RIO, to improve readability
367
        if last_line is not None and len(line) > 2:
368
            line = line[2:]
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
369
        line = re.sub(b'\r', b'', line)
370
        line = re.sub(b'\\\\(.|\n)', mapget, line)
1551.12.9 by Aaron Bentley
force patch-rio to 76 characters
371
        if last_line is None:
372
            last_line = line
373
        else:
374
            last_line += line
6684.1.6 by Martin
Finish making rio module string usage work on Python 3
375
        if last_line[-1:] == b'\n':
1551.12.9 by Aaron Bentley
force patch-rio to 76 characters
376
            yield last_line
377
            last_line = None
378
    if last_line is not None:
379
        yield last_line
1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
380
1551.12.23 by Aaron Bentley
Indent line continuations in Patch-RIO, to improve readability
381
1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
382
def read_patch_stanza(line_iter):
1551.12.38 by Aaron Bentley
Add docs for MergeDirective and RIO-patch functions
383
    """Convert an iterable of RIO-Patch format lines into a Stanza.
384
385
    RIO-Patch is a RIO variant designed to be e-mailed as part of a patch.
386
    It resists common forms of damage such as newline conversion or the removal
387
    of trailing whitespace, yet is also reasonably easy to read.
388
389
    :return: a Stanza
390
    """
1551.12.1 by Aaron Bentley
Basic RIO patch-compatible format is working
391
    return read_stanza(_patch_stanza_iter(line_iter))
4354.3.1 by Jelmer Vernooij
Move core RIO parsing functionality to _rio_py.py.
392
393
394
try:
6624 by Jelmer Vernooij
Merge Python3 porting work ('py3 pokes')
395
    from ._rio_pyx import (
4354.3.1 by Jelmer Vernooij
Move core RIO parsing functionality to _rio_py.py.
396
        _read_stanza_utf8,
397
        _read_stanza_unicode,
398
        _valid_tag,
399
        )
6619.3.2 by Jelmer Vernooij
Apply 2to3 except fix.
400
except ImportError as e:
4574.3.8 by Martin Pool
Only mutter extension load errors when they occur, and record for later
401
    osutils.failed_to_load_extension(e)
6624 by Jelmer Vernooij
Merge Python3 porting work ('py3 pokes')
402
    from ._rio_py import (
7143.15.2 by Jelmer Vernooij
Run autopep8.
403
        _read_stanza_utf8,
404
        _read_stanza_unicode,
405
        _valid_tag,
406
        )