delta: exclude base candidate much smaller than the target
If a revision's full text is that much bigger than a base candidate full text,
we no longer consider that candidate.
This solves a pathological case we encountered on a very specify repository.
It contains a long series of changesets with a very small manifest (one file)
co-existing with others changesets using a very large manifest.
Without this filtering, we ended up considering a large number of tiny full
snapshots as a potential base. It resulted in very large delta (the size of
the full text) and mercurial spending 99% of its time compressing these
deltas.
The timing of a commit moved from about 400s to about 10s (still slow, but not
ridiculously slow).
#!/usr/bin/env python
#
# hggettext - carefully extract docstrings 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.
# The normalize function is taken from pygettext which is distributed
# with Python under the Python License, which is GPL compatible.
"""Extract docstrings from Mercurial commands.
Compared to pygettext, this script knows about the cmdtable and table
dictionaries used by Mercurial, and will only extract docstrings from
functions mentioned therein.
Use xgettext like normal to extract strings marked as translatable and
join the message cataloges to get the final catalog.
"""
from __future__ import absolute_import, print_function
import inspect
import os
import re
import sys
def escape(s):
# The order is important, the backslash must be escaped first
# since the other replacements introduce new backslashes
# themselves.
s = s.replace('\\', '\\\\')
s = s.replace('\n', '\\n')
s = s.replace('\r', '\\r')
s = s.replace('\t', '\\t')
s = s.replace('"', '\\"')
return s
def normalize(s):
# This converts the various Python string types into a format that
# is appropriate for .po files, namely much closer to C style.
lines = s.split('\n')
if len(lines) == 1:
s = '"' + escape(s) + '"'
else:
if not lines[-1]:
del lines[-1]
lines[-1] = lines[-1] + '\n'
lines = map(escape, lines)
lineterm = '\\n"\n"'
s = '""\n"' + lineterm.join(lines) + '"'
return s
def poentry(path, lineno, s):
return ('#: %s:%d\n' % (path, lineno) +
'msgid %s\n' % normalize(s) +
'msgstr ""\n')
doctestre = re.compile(r'^ +>>> ', re.MULTILINE)
def offset(src, doc, name, lineno, default):
"""Compute offset or issue a warning on stdout."""
# remove doctest part, in order to avoid backslash mismatching
m = doctestre.search(doc)
if m:
doc = doc[:m.start()]
# Backslashes in doc appear doubled in src.
end = src.find(doc.replace('\\', '\\\\'))
if end == -1:
# This can happen if the docstring contains unnecessary escape
# sequences such as \" in a triple-quoted string. The problem
# is that \" is turned into " and so doc wont appear in src.
sys.stderr.write("%s:%d:warning:"
" unknown docstr offset, assuming %d lines\n"
% (name, lineno, default))
return default
else:
return src.count('\n', 0, end)
def importpath(path):
"""Import a path like foo/bar/baz.py and return the baz module."""
if path.endswith('.py'):
path = path[:-3]
if path.endswith('/__init__'):
path = path[:-9]
path = path.replace('/', '.')
mod = __import__(path)
for comp in path.split('.')[1:]:
mod = getattr(mod, comp)
return mod
def docstrings(path):
"""Extract docstrings from path.
This respects the Mercurial cmdtable/table convention and will
only extract docstrings from functions mentioned in these tables.
"""
mod = importpath(path)
if not path.startswith('mercurial/') and mod.__doc__:
with open(path) as fobj:
src = fobj.read()
lineno = 1 + offset(src, mod.__doc__, path, 1, 7)
print(poentry(path, lineno, mod.__doc__))
functions = list(getattr(mod, 'i18nfunctions', []))
functions = [(f, True) for f in functions]
cmdtable = getattr(mod, 'cmdtable', {})
if not cmdtable:
# Maybe we are processing mercurial.commands?
cmdtable = getattr(mod, 'table', {})
functions.extend((c[0], False) for c in cmdtable.itervalues())
for func, rstrip in functions:
if func.__doc__:
docobj = func # this might be a proxy to provide formatted doc
func = getattr(func, '_origfunc', func)
funcmod = inspect.getmodule(func)
extra = ''
if funcmod.__package__ == funcmod.__name__:
extra = '/__init__'
actualpath = '%s%s.py' % (funcmod.__name__.replace('.', '/'), extra)
src = inspect.getsource(func)
lineno = inspect.getsourcelines(func)[1]
doc = docobj.__doc__
origdoc = getattr(docobj, '_origdoc', '')
if rstrip:
doc = doc.rstrip()
origdoc = origdoc.rstrip()
if origdoc:
lineno += offset(src, origdoc, actualpath, lineno, 1)
else:
lineno += offset(src, doc, actualpath, lineno, 1)
print(poentry(actualpath, lineno, doc))
def rawtext(path):
with open(path) as f:
src = f.read()
print(poentry(path, 1, src))
if __name__ == "__main__":
# It is very important that we import the Mercurial modules from
# the source tree where hggettext is executed. Otherwise we might
# accidentally import and extract strings from a Mercurial
# installation mentioned in PYTHONPATH.
sys.path.insert(0, os.getcwd())
from mercurial import demandimport; demandimport.enable()
for path in sys.argv[1:]:
if path.endswith('.txt'):
rawtext(path)
else:
docstrings(path)