record: allow splitting of hunks by manually editing patches
It is possible that unrelated changes in a file are on sequential lines. The
current record extension does not allow these to be committed independently.
An example use case for this is in software development for deeply embedded
real-time systems. In these environments, it is not always possible to use a
debugger (due to time-constraints) and hence inline UART-based printing is
often used. When fixing a bug in a module, it is often convenient to add a
large number of 'printf's (linked to the UART via a custom fputc) to the module
in order to work out what is going wrong. printf is a very slow function (and
also variadic so somewhat frowned upon by the MISRA standard) and hence it is
highly undesirable to commit these lines to the repository. If only a partial
fix is implemented, however, it is desirable to commit the fix without deleting
all of the printf lines. This is also simplifies removal of the printf lines
as once the final fix is committed, 'hg revert' does the rest. It is likely
that the printf lines will be very near the actual fix, so being able to split
the hunk is very useful in this case.
There were two alternatives I considered for the user interface. One was to
manually edit the patch, the other to allow a hunk to be split into individual
lines for consideration. The latter option would require a significant
refactor of the record module and is less flexible. While the former is
potentially more complicated to use, this is a feature that is likely to only
be used in certain exceptional cases (such as the use case proposed above) and
hence I felt that the complexity would not be a considerable issue.
I've also written a follow-up patch that refactors the 'prompt' code to base
everything on the choices variable. This tidies up and clarifies the code a
bit (removes constructs like 'if ret == 7' and removes the 'e' option from the
file scope options as it's not relevant there. It's not really a necessity, so
I've excluded it from this submission for now, but I can send it separately if
there's a desire and it's on bitbucket (see below) in the meantime.
Possible future improvements include:
* Tidying up the 'prompt' code to base everything on the choices variable.
This would allow entries to be removed from the prompt as currently 'e' is
offered even for entire file patches, which is currently unsupported.
* Allowing the entire file (or even multi-file) patch to be edited manually:
this would require quite a large refactor without much benefit, so I decided
to exclude it from the initial submission.
* Allow the option to retry if a patch fails to apply (this is what Git does).
This would require quite a bit of refactoring given the current 'hg record'
implementation, so it's debatable whether it's worth it.
Output is similar to existing record user interface except that an additional
option ('e') exists to allow manual editing of the patch. This opens the
user's configured editor with the patch. A comment is added to the bottom of
the patch explaining what to do (based on Git's one).
A large proportion of the changeset is test-case changes to update the options
reported by record (Ynesfdaq? instead of Ynsfdaq?). Functional changes are in
record.py and there are some new test cases in test-record.t.
# win32mbcs.py -- MBCS filename support for Mercurial
#
# Copyright (c) 2008 Shun-ichi Goto <shunichi.goto@gmail.com>
#
# Version: 0.3
# Author: Shun-ichi Goto <shunichi.goto@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
#
'''allow the use of MBCS paths with problematic encodings
Some MBCS encodings are not good for some path operations (i.e.
splitting path, case conversion, etc.) with its encoded bytes. We call
such a encoding (i.e. shift_jis and big5) as "problematic encoding".
This extension can be used to fix the issue with those encodings by
wrapping some functions to convert to Unicode string before path
operation.
This extension is useful for:
- Japanese Windows users using shift_jis encoding.
- Chinese Windows users using big5 encoding.
- All users who use a repository with one of problematic encodings on
case-insensitive file system.
This extension is not needed for:
- Any user who use only ASCII chars in path.
- Any user who do not use any of problematic encodings.
Note that there are some limitations on using this extension:
- You should use single encoding in one repository.
- If the repository path ends with 0x5c, .hg/hgrc cannot be read.
- win32mbcs is not compatible with fixutf8 extension.
By default, win32mbcs uses encoding.encoding decided by Mercurial.
You can specify the encoding by config option::
[win32mbcs]
encoding = sjis
It is useful for the users who want to commit with UTF-8 log message.
'''
import os, sys
from mercurial.i18n import _
from mercurial import util, encoding
_encoding = None # see extsetup
def decode(arg):
if isinstance(arg, str):
uarg = arg.decode(_encoding)
if arg == uarg.encode(_encoding):
return uarg
raise UnicodeError("Not local encoding")
elif isinstance(arg, tuple):
return tuple(map(decode, arg))
elif isinstance(arg, list):
return map(decode, arg)
elif isinstance(arg, dict):
for k, v in arg.items():
arg[k] = decode(v)
return arg
def encode(arg):
if isinstance(arg, unicode):
return arg.encode(_encoding)
elif isinstance(arg, tuple):
return tuple(map(encode, arg))
elif isinstance(arg, list):
return map(encode, arg)
elif isinstance(arg, dict):
for k, v in arg.items():
arg[k] = encode(v)
return arg
def appendsep(s):
# ensure the path ends with os.sep, appending it if necessary.
try:
us = decode(s)
except UnicodeError:
us = s
if us and us[-1] not in ':/\\':
s += os.sep
return s
def wrapper(func, args, kwds):
# check argument is unicode, then call original
for arg in args:
if isinstance(arg, unicode):
return func(*args, **kwds)
try:
# convert arguments to unicode, call func, then convert back
return encode(func(*decode(args), **decode(kwds)))
except UnicodeError:
raise util.Abort(_("[win32mbcs] filename conversion failed with"
" %s encoding\n") % (_encoding))
def wrapperforlistdir(func, args, kwds):
# Ensure 'path' argument ends with os.sep to avoids
# misinterpreting last 0x5c of MBCS 2nd byte as path separator.
if args:
args = list(args)
args[0] = appendsep(args[0])
if 'path' in kwds:
kwds['path'] = appendsep(kwds['path'])
return func(*args, **kwds)
def wrapname(name, wrapper):
module, name = name.rsplit('.', 1)
module = sys.modules[module]
func = getattr(module, name)
def f(*args, **kwds):
return wrapper(func, args, kwds)
try:
f.__name__ = func.__name__ # fail with python23
except Exception:
pass
setattr(module, name, f)
# List of functions to be wrapped.
# NOTE: os.path.dirname() and os.path.basename() are safe because
# they use result of os.path.split()
funcs = '''os.path.join os.path.split os.path.splitext
os.path.normpath os.makedirs
mercurial.util.endswithsep mercurial.util.splitpath mercurial.util.checkcase
mercurial.util.fspath mercurial.util.pconvert mercurial.util.normpath
mercurial.util.checkwinfilename mercurial.util.checkosfilename'''
# List of Windows specific functions to be wrapped.
winfuncs = '''os.path.splitunc'''
# codec and alias names of sjis and big5 to be faked.
problematic_encodings = '''big5 big5-tw csbig5 big5hkscs big5-hkscs
hkscs cp932 932 ms932 mskanji ms-kanji shift_jis csshiftjis shiftjis
sjis s_jis shift_jis_2004 shiftjis2004 sjis_2004 sjis2004
shift_jisx0213 shiftjisx0213 sjisx0213 s_jisx0213 950 cp950 ms950 '''
def extsetup(ui):
# TODO: decide use of config section for this extension
if ((not os.path.supports_unicode_filenames) and
(sys.platform != 'cygwin')):
ui.warn(_("[win32mbcs] cannot activate on this platform.\n"))
return
# determine encoding for filename
global _encoding
_encoding = ui.config('win32mbcs', 'encoding', encoding.encoding)
# fake is only for relevant environment.
if _encoding.lower() in problematic_encodings.split():
for f in funcs.split():
wrapname(f, wrapper)
if os.name == 'nt':
for f in winfuncs.split():
wrapname(f, wrapper)
wrapname("mercurial.osutil.listdir", wrapperforlistdir)
# Check sys.args manually instead of using ui.debug() because
# command line options is not yet applied when
# extensions.loadall() is called.
if '--debug' in sys.argv:
ui.write("[win32mbcs] activated with encoding: %s\n"
% _encoding)