Fix special character conversion

Author: pplulee

telebot/formatting.py

@@ -425,15 +425,14 @@ def func(upd_text, subst_type=None, url=None, user=None, custom_emoji_id=None, l
             url = "tg://user?id={0}".format(user.id)
         elif subst_type == "mention":
             url = "https://t.me/{0}".format(upd_text[1:])
-        elif subst_type == "pre":
-            if language is not None:
-                return '<pre><code class="language-{0}">{1}</code></pre>'.format(language, upd_text)
         upd_text = upd_text.replace("&", "&amp;").replace("<", "&lt;").replace(">", "&gt;")
         if not subst_type or not _subs.get(subst_type):
             return upd_text
         subs = _subs.get(subst_type)
         if subst_type == "custom_emoji":
             return subs.format(text=upd_text, custom_emoji_id=custom_emoji_id)
+        elif (subst_type == "pre") and language:
+            return "<pre><code class=\"language-{0}\">{1}</code></pre>".format(language, upd_text)
         return subs.format(text=upd_text, url=url)
 
     offset = 0

tests/test_telebot.py

@@ -716,6 +716,7 @@ def test_apply_html_entities(self):
             "`inline code`": "<code>inline code</code>",
             "```\ncode block```": "<pre>code block</pre>",
             "```python\nprint('Hello, world!')\n```": "<pre><code class=\"language-python\">print('Hello, world!')</code></pre>",
+            "```python\nprint(1 < 2)\n```": "<pre><code class=\"language-python\">print(1 &lt; 2)</code></pre>",
             "[link](http://example.com/)": "<a href=\"http://example.com/\">link</a>",
             ">blockquote": "<blockquote>blockquote</blockquote>",
         }