fix(util): drop the empty part smart_split appends, accept None in extract_arguments

telebot/util.py

@@ -279,6 +279,7 @@ def extract_arguments(text: str) -> Union[str, None]:
     :rtype: :obj:`str` or :obj:`None`
     """
     regexp = re.compile(r"/\w*(@\w*)*\s*([\s\S]*)", re.IGNORECASE)
+    if text is None: return None
     result = regexp.match(text)
     return result.group(2) if is_command(text) else None
 
@@ -357,7 +358,7 @@ def _text_before_last(substr: str) -> str:
 
     parts = []
     while True:
-        if len(text) < chars_per_string:
+        if len(text) <= chars_per_string:
             parts.append(text)
             return parts
 

tests/test_util.py

@@ -0,0 +1,38 @@
+from telebot import util
+
+
+def test_smart_split_exact_multiple_has_no_trailing_empty_part():
+    # A chunk boundary landing exactly on the limit used to append an empty part.
+    for size in (1, 2, 3, 4, 10):
+        for chunks in (1, 2, 3):
+            text = "a" * (size * chunks)
+            assert util.smart_split(text, size) == ["a" * size] * chunks
+
+
+def test_smart_split_short_text():
+    assert util.smart_split("abc", 3) == ["abc"]
+    assert util.smart_split("abcde", 3) == ["abc", "de"]
+    assert util.smart_split("", 3) == [""]
+
+
+def test_smart_split_prefers_newline_then_space():
+    assert util.smart_split("one two\nthree four", 10) == ["one two\n", "three four"]
+    assert util.smart_split("one two three", 8) == ["one two ", "three"]
+
+
+def test_smart_split_caps_at_max_message_length():
+    parts = util.smart_split("a" * (util.MAX_MESSAGE_LENGTH * 2), util.MAX_MESSAGE_LENGTH * 5)
+    assert [len(p) for p in parts] == [util.MAX_MESSAGE_LENGTH] * 2
+
+
+def test_extract_arguments_accepts_none():
+    # message.text is None for non-text messages
+    assert util.extract_arguments(None) is None  # type: ignore[arg-type]
+    assert util.extract_command(None) is None  # type: ignore[arg-type]
+
+
+def test_extract_arguments_values():
+    assert util.extract_arguments("/get name") == "name"
+    assert util.extract_arguments("/get") == ""
+    assert util.extract_arguments("/get@bot name") == "name"
+    assert util.extract_arguments("hello") is None