1  """Tests for Telegram bot mention detection (bug #12545).
  2  
  3  The old implementation used a naive substring check
  4  (`f"@{bot_username}" in text.lower()`), which incorrectly matched partial
  5  substrings like 'foo@hermes_bot.example'.
  6  
  7  Detection now relies entirely on the MessageEntity objects Telegram's server
  8  emits for real mentions. A bare `@username` substring in message text without
  9  a corresponding `MENTION` entity is NOT a mention — this correctly ignores
 10  @handles that appear inside URLs, code blocks, email-like strings, or quoted
 11  text, because Telegram's parser does not emit mention entities for any of
 12  those contexts.
 13  """
 14  from types import SimpleNamespace
 15  
 16  from gateway.config import Platform, PlatformConfig
 17  from gateway.platforms.telegram import TelegramAdapter
 18  
 19  
 20  def _make_adapter():
 21      adapter = object.__new__(TelegramAdapter)
 22      adapter.platform = Platform.TELEGRAM
 23      adapter.config = PlatformConfig(enabled=True, token="***", extra={})
 24      adapter._bot = SimpleNamespace(id=999, username="hermes_bot")
 25      return adapter
 26  
 27  
 28  def _mention_entity(text, mention="@hermes_bot"):
 29      """Build a MENTION entity pointing at a literal `@username` in `text`."""
 30      offset = text.index(mention)
 31      return SimpleNamespace(type="mention", offset=offset, length=len(mention))
 32  
 33  
 34  def _text_mention_entity(offset, length, user_id):
 35      """Build a TEXT_MENTION entity (used when the target user has no public @handle)."""
 36      return SimpleNamespace(
 37          type="text_mention",
 38          offset=offset,
 39          length=length,
 40          user=SimpleNamespace(id=user_id),
 41      )
 42  
 43  
 44  def _message(text=None, caption=None, entities=None, caption_entities=None):
 45      return SimpleNamespace(
 46          text=text,
 47          caption=caption,
 48          entities=entities or [],
 49          caption_entities=caption_entities or [],
 50          message_thread_id=None,
 51          chat=SimpleNamespace(id=-100, type="group"),
 52          reply_to_message=None,
 53      )
 54  
 55  
 56  class TestRealMentionsAreDetected:
 57      """A real Telegram mention always comes with a MENTION entity — detect those."""
 58  
 59      def test_mention_at_start_of_message(self):
 60          adapter = _make_adapter()
 61          text = "@hermes_bot hello world"
 62          msg = _message(text=text, entities=[_mention_entity(text)])
 63          assert adapter._message_mentions_bot(msg) is True
 64  
 65      def test_mention_mid_sentence(self):
 66          adapter = _make_adapter()
 67          text = "hey @hermes_bot, can you help?"
 68          msg = _message(text=text, entities=[_mention_entity(text)])
 69          assert adapter._message_mentions_bot(msg) is True
 70  
 71      def test_mention_at_end_of_message(self):
 72          adapter = _make_adapter()
 73          text = "thanks for looking @hermes_bot"
 74          msg = _message(text=text, entities=[_mention_entity(text)])
 75          assert adapter._message_mentions_bot(msg) is True
 76  
 77      def test_mention_in_caption(self):
 78          adapter = _make_adapter()
 79          caption = "photo for @hermes_bot"
 80          msg = _message(caption=caption, caption_entities=[_mention_entity(caption)])
 81          assert adapter._message_mentions_bot(msg) is True
 82  
 83      def test_text_mention_entity_targets_bot(self):
 84          """TEXT_MENTION is Telegram's entity type for @FirstName -> user without a public handle."""
 85          adapter = _make_adapter()
 86          msg = _message(text="hey you", entities=[_text_mention_entity(4, 3, user_id=999)])
 87          assert adapter._message_mentions_bot(msg) is True
 88  
 89  
 90  class TestSubstringFalsePositivesAreRejected:
 91      """Bare `@bot_username` substrings without a MENTION entity must NOT match.
 92  
 93      These are all inputs where the OLD substring check returned True incorrectly.
 94      A word-boundary regex would still over-match some of these (code blocks,
 95      URLs). Entity-based detection handles them all correctly because Telegram's
 96      parser does not emit mention entities for non-mention contexts.
 97      """
 98  
 99      def test_email_like_substring(self):
100          """bug #12545 exact repro: 'foo@hermes_bot.example'."""
101          adapter = _make_adapter()
102          msg = _message(text="email me at foo@hermes_bot.example")
103          assert adapter._message_mentions_bot(msg) is False
104  
105      def test_hostname_substring(self):
106          adapter = _make_adapter()
107          msg = _message(text="contact user@hermes_bot.domain.com")
108          assert adapter._message_mentions_bot(msg) is False
109  
110      def test_superstring_username(self):
111          """`@hermes_botx` is a different username; Telegram would emit a mention
112          entity for `@hermes_botx`, not `@hermes_bot`."""
113          adapter = _make_adapter()
114          msg = _message(text="@hermes_botx hello")
115          assert adapter._message_mentions_bot(msg) is False
116  
117      def test_underscore_suffix_substring(self):
118          adapter = _make_adapter()
119          msg = _message(text="see @hermes_bot_admin for help")
120          assert adapter._message_mentions_bot(msg) is False
121  
122      def test_substring_inside_url_without_entity(self):
123          """@handle inside a URL produces a URL entity, not a MENTION entity."""
124          adapter = _make_adapter()
125          msg = _message(text="see https://example.com/@hermes_bot for details")
126          assert adapter._message_mentions_bot(msg) is False
127  
128      def test_substring_inside_code_block_without_entity(self):
129          """Telegram doesn't emit mention entities inside code/pre entities."""
130          adapter = _make_adapter()
131          msg = _message(text="use the string `@hermes_bot` in config")
132          assert adapter._message_mentions_bot(msg) is False
133  
134      def test_plain_text_with_no_at_sign(self):
135          adapter = _make_adapter()
136          msg = _message(text="just a normal group message")
137          assert adapter._message_mentions_bot(msg) is False
138  
139      def test_email_substring_in_caption(self):
140          adapter = _make_adapter()
141          msg = _message(caption="foo@hermes_bot.example")
142          assert adapter._message_mentions_bot(msg) is False
143  
144  
145  class TestEntityEdgeCases:
146      """Malformed or mismatched entities should not crash or over-match."""
147  
148      def test_mention_entity_for_different_username(self):
149          adapter = _make_adapter()
150          text = "@someone_else hi"
151          msg = _message(text=text, entities=[_mention_entity(text, mention="@someone_else")])
152          assert adapter._message_mentions_bot(msg) is False
153  
154      def test_text_mention_entity_for_different_user(self):
155          adapter = _make_adapter()
156          msg = _message(text="hi there", entities=[_text_mention_entity(0, 2, user_id=12345)])
157          assert adapter._message_mentions_bot(msg) is False
158  
159      def test_malformed_entity_with_negative_offset(self):
160          adapter = _make_adapter()
161          msg = _message(text="@hermes_bot hi",
162                         entities=[SimpleNamespace(type="mention", offset=-1, length=11)])
163          assert adapter._message_mentions_bot(msg) is False
164  
165      def test_malformed_entity_with_zero_length(self):
166          adapter = _make_adapter()
167          msg = _message(text="@hermes_bot hi",
168                         entities=[SimpleNamespace(type="mention", offset=0, length=0)])
169          assert adapter._message_mentions_bot(msg) is False
170  
171  
172  class TestCaseInsensitivity:
173      """Telegram usernames are case-insensitive; the slice-compare normalizes both sides."""
174  
175      def test_uppercase_mention(self):
176          adapter = _make_adapter()
177          text = "hi @HERMES_BOT"
178          msg = _message(text=text, entities=[_mention_entity(text, mention="@HERMES_BOT")])
179          assert adapter._message_mentions_bot(msg) is True
180  
181      def test_mixed_case_mention(self):
182          adapter = _make_adapter()
183          text = "hi @Hermes_Bot"
184          msg = _message(text=text, entities=[_mention_entity(text, mention="@Hermes_Bot")])
185          assert adapter._message_mentions_bot(msg) is True