bookflow: new extension for bookmark-based branching
This extension should be helpful for feature branches - based workflows.
At my company we first considered branches, but weren't sure about creating a lot of permanent objects.
We tried bookmarks, but found some scenarios to be difficult to control.
The main problem, was the active bookmark being moved on update.
Disabling that made everything a lot more predictable.
Bookmarks move on commit, and updating means switching between them.
The extension also implements a few minor features to better guide the workflow:
- hg bookmark NAME can be ambiguous (create or move), unlike hg branch. The extension requires -rev to move.
- require an active bookmark on commit.
- some bookmarks can be protected (like @), useful for teams, that require code reviews.
- block creation of new branches.
The initial implementation requires no changes in the core, but it does rely on some implementation details.
I thought it may be useful to discuss the functionality first, and then focus making the code more robust.
Differential Revision: https://phab.mercurial-scm.org/D4312
# config.py - configuration parsing for Mercurial
#
# Copyright 2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import errno
import os
from .i18n import _
from . import (
error,
pycompat,
util,
)
class config(object):
def __init__(self, data=None, includepaths=None):
self._data = {}
self._unset = []
self._includepaths = includepaths or []
if data:
for k in data._data:
self._data[k] = data[k].copy()
self._source = data._source.copy()
else:
self._source = util.cowdict()
def copy(self):
return config(self)
def __contains__(self, section):
return section in self._data
def hasitem(self, section, item):
return item in self._data.get(section, {})
def __getitem__(self, section):
return self._data.get(section, {})
def __iter__(self):
for d in self.sections():
yield d
def update(self, src):
self._source = self._source.preparewrite()
for s, n in src._unset:
ds = self._data.get(s, None)
if ds is not None and n in ds:
self._data[s] = ds.preparewrite()
del self._data[s][n]
del self._source[(s, n)]
for s in src:
ds = self._data.get(s, None)
if ds:
self._data[s] = ds.preparewrite()
else:
self._data[s] = util.cowsortdict()
self._data[s].update(src._data[s])
self._source.update(src._source)
def get(self, section, item, default=None):
return self._data.get(section, {}).get(item, default)
def backup(self, section, item):
"""return a tuple allowing restore to reinstall a previous value
The main reason we need it is because it handles the "no data" case.
"""
try:
value = self._data[section][item]
source = self.source(section, item)
return (section, item, value, source)
except KeyError:
return (section, item)
def source(self, section, item):
return self._source.get((section, item), "")
def sections(self):
return sorted(self._data.keys())
def items(self, section):
return list(self._data.get(section, {}).iteritems())
def set(self, section, item, value, source=""):
if pycompat.ispy3:
assert not isinstance(value, str), (
'config values may not be unicode strings on Python 3')
if section not in self:
self._data[section] = util.cowsortdict()
else:
self._data[section] = self._data[section].preparewrite()
self._data[section][item] = value
if source:
self._source = self._source.preparewrite()
self._source[(section, item)] = source
def restore(self, data):
"""restore data returned by self.backup"""
self._source = self._source.preparewrite()
if len(data) == 4:
# restore old data
section, item, value, source = data
self._data[section] = self._data[section].preparewrite()
self._data[section][item] = value
self._source[(section, item)] = source
else:
# no data before, remove everything
section, item = data
if section in self._data:
self._data[section].pop(item, None)
self._source.pop((section, item), None)
def parse(self, src, data, sections=None, remap=None, include=None):
sectionre = util.re.compile(br'\[([^\[]+)\]')
itemre = util.re.compile(br'([^=\s][^=]*?)\s*=\s*(.*\S|)')
contre = util.re.compile(br'\s+(\S|\S.*\S)\s*$')
emptyre = util.re.compile(br'(;|#|\s*$)')
commentre = util.re.compile(br'(;|#)')
unsetre = util.re.compile(br'%unset\s+(\S+)')
includere = util.re.compile(br'%include\s+(\S|\S.*\S)\s*$')
section = ""
item = None
line = 0
cont = False
if remap:
section = remap.get(section, section)
for l in data.splitlines(True):
line += 1
if line == 1 and l.startswith('\xef\xbb\xbf'):
# Someone set us up the BOM
l = l[3:]
if cont:
if commentre.match(l):
continue
m = contre.match(l)
if m:
if sections and section not in sections:
continue
v = self.get(section, item) + "\n" + m.group(1)
self.set(section, item, v, "%s:%d" % (src, line))
continue
item = None
cont = False
m = includere.match(l)
if m and include:
expanded = util.expandpath(m.group(1))
includepaths = [os.path.dirname(src)] + self._includepaths
for base in includepaths:
inc = os.path.normpath(os.path.join(base, expanded))
try:
include(inc, remap=remap, sections=sections)
break
except IOError as inst:
if inst.errno != errno.ENOENT:
raise error.ParseError(_("cannot include %s (%s)")
% (inc, inst.strerror),
"%s:%d" % (src, line))
continue
if emptyre.match(l):
continue
m = sectionre.match(l)
if m:
section = m.group(1)
if remap:
section = remap.get(section, section)
if section not in self:
self._data[section] = util.cowsortdict()
continue
m = itemre.match(l)
if m:
item = m.group(1)
cont = True
if sections and section not in sections:
continue
self.set(section, item, m.group(2), "%s:%d" % (src, line))
continue
m = unsetre.match(l)
if m:
name = m.group(1)
if sections and section not in sections:
continue
if self.get(section, name) is not None:
self._data[section] = self._data[section].preparewrite()
del self._data[section][name]
self._unset.append((section, name))
continue
raise error.ParseError(l.rstrip(), ("%s:%d" % (src, line)))
def read(self, path, fp=None, sections=None, remap=None):
if not fp:
fp = util.posixfile(path, 'rb')
assert getattr(fp, 'mode', r'rb') == r'rb', (
'config files must be opened in binary mode, got fp=%r mode=%r' % (
fp, fp.mode))
self.parse(path, fp.read(),
sections=sections, remap=remap, include=self.read)
def parselist(value):
"""parse a configuration value as a list of comma/space separated strings
>>> parselist(b'this,is "a small" ,test')
['this', 'is', 'a small', 'test']
"""
def _parse_plain(parts, s, offset):
whitespace = False
while offset < len(s) and (s[offset:offset + 1].isspace()
or s[offset:offset + 1] == ','):
whitespace = True
offset += 1
if offset >= len(s):
return None, parts, offset
if whitespace:
parts.append('')
if s[offset:offset + 1] == '"' and not parts[-1]:
return _parse_quote, parts, offset + 1
elif s[offset:offset + 1] == '"' and parts[-1][-1:] == '\\':
parts[-1] = parts[-1][:-1] + s[offset:offset + 1]
return _parse_plain, parts, offset + 1
parts[-1] += s[offset:offset + 1]
return _parse_plain, parts, offset + 1
def _parse_quote(parts, s, offset):
if offset < len(s) and s[offset:offset + 1] == '"': # ""
parts.append('')
offset += 1
while offset < len(s) and (s[offset:offset + 1].isspace() or
s[offset:offset + 1] == ','):
offset += 1
return _parse_plain, parts, offset
while offset < len(s) and s[offset:offset + 1] != '"':
if (s[offset:offset + 1] == '\\' and offset + 1 < len(s)
and s[offset + 1:offset + 2] == '"'):
offset += 1
parts[-1] += '"'
else:
parts[-1] += s[offset:offset + 1]
offset += 1
if offset >= len(s):
real_parts = _configlist(parts[-1])
if not real_parts:
parts[-1] = '"'
else:
real_parts[0] = '"' + real_parts[0]
parts = parts[:-1]
parts.extend(real_parts)
return None, parts, offset
offset += 1
while offset < len(s) and s[offset:offset + 1] in [' ', ',']:
offset += 1
if offset < len(s):
if offset + 1 == len(s) and s[offset:offset + 1] == '"':
parts[-1] += '"'
offset += 1
else:
parts.append('')
else:
return None, parts, offset
return _parse_plain, parts, offset
def _configlist(s):
s = s.rstrip(' ,')
if not s:
return []
parser, parts, offset = _parse_plain, [''], 0
while parser:
parser, parts, offset = parser(parts, s, offset)
return parts
if value is not None and isinstance(value, bytes):
result = _configlist(value.lstrip(' ,\n'))
else:
result = value
return result or []