fix: pendulum.parse('2007-12-13/14:30') raised TypeError instead of uniform ValueError

Time object was falling through type checks in Interval.__new__

Author: alexanderlukanin13

src/pendulum/interval.py

@@ -39,8 +39,9 @@ class Interval(Duration, Generic[_T]):
     """
 
     def __new__(cls, start: _T, end: _T, absolute: bool = False) -> Self:
-        if (isinstance(start, datetime) and not isinstance(end, datetime)) or (
-            not isinstance(start, datetime) and isinstance(end, datetime)
+        if (isinstance(start, datetime) and not isinstance(end, datetime) or
+            not isinstance(start, datetime) and isinstance(end, datetime) or
+            not (isinstance(start, date) and isinstance(end, date))  # Time not allowed
         ):
             raise ValueError(
                 "Both start and end of an Interval must have the same type"

tests/test_parsing.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import pytest
+
 import pendulum
 
 from tests.conftest import assert_date
@@ -127,6 +129,19 @@ def test_parse_interval() -> None:
     assert interval.end.offset == 0
 
 
+def test_parse_interval_mixed_types():
+    error = 'Both start and end of an Interval must have the same type'
+
+    # date / time is not allowed in ISO 8601
+    with pytest.raises(ValueError, match=error):
+        pendulum.parse('2007-12-13/14:30')
+
+    # datetime / time is allowed in some lenient ISO 8601 implementations (e.g. aniso8601 package).
+    # Not allowed in pendulum for strictness and consistency.
+    with pytest.raises(ValueError, match=error):
+        pendulum.parse('2007-12-13T14:30/15:45')
+
+
 def test_parse_now() -> None:
     assert pendulum.parse("now").timezone_name == "UTC"
     assert (