i18n: leave out entries which contain only a rst directive

This prevents the danger of translating entries like ".. note::"

i18n/posplit

@@ -1,66 +1,69
 #!/usr/bin/env python
 #
 # posplit - split messages in paragraphs on .po/.pot files
 #
 # license: MIT/X11/Expat
 #
 
 import re
 import sys
 import polib
 
 def addentry(po, entry, cache):
     e = cache.get(entry.msgid)
     if e:
         e.occurrences.extend(entry.occurrences)
     else:
         po.append(entry)
         cache[entry.msgid] = entry
 
 def mkentry(orig, delta, msgid, msgstr):
     entry = polib.POEntry()
     entry.merge(orig)
     entry.msgid = msgid or orig.msgid
     entry.msgstr = msgstr or orig.msgstr
     entry.occurrences = [(p, int(l) + delta) for (p, l) in orig.occurrences]
     return entry
 
 if __name__ == "__main__":
     po = polib.pofile(sys.argv[1])
 
     cache = {}
     entries = po[:]
     po[:] = []
     findd = re.compile(r' *\.\. (\w+)::') # for finding directives
     for entry in entries:
         msgids = entry.msgid.split(u'\n\n')
         if entry.msgstr:
             msgstrs = entry.msgstr.split(u'\n\n')
         else:
             msgstrs = [u''] * len(msgids)
 
         if len(msgids) != len(msgstrs):
             # places the whole existing translation as a fuzzy
             # translation for each paragraph, to give the
             # translator a chance to recover part of the old
             # translation - erasing extra paragraphs is
             # probably better than retranslating all from start
             if 'fuzzy' not in entry.flags:
                 entry.flags.append('fuzzy')
             msgstrs = [entry.msgstr] * len(msgids)
 
         delta = 0
         for msgid, msgstr in zip(msgids, msgstrs):
             if msgid and msgid != '::':
                 newentry = mkentry(entry, delta, msgid, msgstr)
                 mdirective = findd.match(msgid)
                 if mdirective:
+                    if not msgid[mdirective.end():].rstrip():
+                        # only directive, nothing to translate here
+                        continue
                     directive = mdirective.group(1)
                     comment = 'do not translate: .. %s::' % directive
                     if not newentry.comment:
                         newentry.comment = comment
                     elif comment not in newentry.comment:
                         newentry.comment += '\n' + comment
                 addentry(po, newentry, cache)
             delta += 2 + msgid.count('\n')
     po.save()