Do not parse links to posts that do not exists in the time of posting.

boards/views.py

@@ -14,10 +14,12 b' from boards import utils'
 from boards.forms import ThreadForm, PostForm, SettingsForm, PlainErrorList, \
     ThreadCaptchaForm, PostCaptchaForm, LoginForm, ModeratorSettingsForm
 
-from boards.models import Post, Tag, Ban, User, RANK_USER, SETTING_MODERATE
+from boards.models import Post, Tag, Ban, User, RANK_USER, SETTING_MODERATE, \
+    REGEX_REPLY
 from boards import authors
 from boards.utils import get_client_ip
 import neboard
+import re
 
 
 def index(request, page=0):
@@ -70,6 +72,8 b' def _new_post(request, form, thread_id=b'
     title = data['title']
     text = data['text']
 
+    text = _remove_invalid_links(text)
+
     if 'image' in data.keys():
         image = data['image']
     else:
@@ -457,3 +461,18 b' def _ban_current_user(request):'
 
     ip = utils.get_client_ip(request)
     Ban.objects.get_or_create(ip=ip)
+
+
+def _remove_invalid_links(text):
+    """
+    Replace invalid links in posts so that they won't be parsed.
+    Invalid links are links to non-existent posts
+    """
+
+    for reply_number in re.finditer(REGEX_REPLY, text):
+	id = reply_number.group(1)
+	post = Post.objects.filter(id=id)
+	if not post.exists():
+	    text = string.replace(text, '>>' + id, id)
+
+    return text