i18n: ignore doctest part to avoid warning at "make update-pot"

hggettext assumes that backslashes in docstring are always doubled in
original source code, in order to find the location of original
docstring out certainly.

This assumption almost always works as expected. But doctest easily
breaks it, because many of backslashes in doctests aren't doubled.
This mismatching causes "unknown offset in ..." warning at "make
update-pot".

To avoid such warning, this patch ignores doctest part of docstring
before finding the location of original docstring out.

BTW, at this patch, only person() in templatefilters.py has doctest
part, which causes "unknown offset ..." warning.

Therefore, just making backslashes in that doctest doubled can avoid
such warning, too. But forcing doctest writers to double backslashes
in doctest isn't reasonable, IMHO.

i18n/hggettext

@@ -1,152 +1,159 b''
 #!/usr/bin/env python
 #
 # hggettext - carefully extract docstrings for Mercurial
 #
 # Copyright 2009 Matt Mackall <[e-mail]> 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, 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("warning: unknown offset in %s, assuming %d lines\n"
                          % (name, 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 mod.__doc__:
         src = open(path).read()
         lineno = 1 + offset(src, mod.__doc__, path, 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__:
             funcmod = inspect.getmodule(func)
             extra = ''
             if funcmod.__package__ == funcmod.__name__:
                 extra = '/__init__'
             actualpath = '%s%s.py' % (funcmod.__name__.replace('.', '/'), extra)
 
             src = inspect.getsource(func)
             name = "%s.%s" % (actualpath, func.__name__)
             lineno = inspect.getsourcelines(func)[1]
             doc = func.__doc__
             origdoc = getattr(func, '_origdoc', '')
             if rstrip:
                 doc = doc.rstrip()
                 origdoc = origdoc.rstrip()
             if origdoc:
                 lineno += offset(src, origdoc, name, 1)
             else:
                 lineno += offset(src, doc, name, 1)
             print(poentry(actualpath, lineno, doc))
 
 
 def rawtext(path):
     src = open(path).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)