Add equality test (#698)

* Add equality test

* Consistency

* Implement equality per subclass

Author: malthe

src/pendulum/tz/timezone.py

@@ -66,6 +66,9 @@ def __new__(cls, key: str) -> Self:
         except zoneinfo.ZoneInfoNotFoundError:
             raise InvalidTimezone(key)
 
+    def __eq__(self, other: object) -> bool:
+        return isinstance(other, Timezone) and self.key == other.key
+
     @property
     def name(self) -> str:
         return self.key
@@ -172,6 +175,9 @@ def __init__(self, offset: int, name: str | None = None) -> None:
         self._offset = offset
         self._utcoffset = _datetime.timedelta(seconds=offset)
 
+    def __eq__(self, other: object) -> bool:
+        return isinstance(other, FixedTimezone) and self._offset == other._offset
+
     @property
     def name(self) -> str:
         return self._name

tests/tz/test_timezone.py

@@ -42,6 +42,11 @@ def test_basic_convert():
     assert dt.tzinfo.dst(dt) == timedelta(seconds=3600)
 
 
+def test_equality():
+    assert timezone("Europe/Paris") == timezone("Europe/Paris")
+    assert timezone("Europe/Paris") != timezone("Europe/Berlin")
+
+
 def test_skipped_time_with_pre_rule():
     dt = datetime(2013, 3, 31, 2, 30, 45, 123456, fold=0)
     tz = timezone("Europe/Paris")
@@ -399,6 +404,11 @@ def test_fixed_timezone():
     assert tz2.dst(dt) == timedelta()
 
 
+def test_fixed_equality():
+    assert fixed_timezone(19800) == fixed_timezone(19800)
+    assert fixed_timezone(19800) != fixed_timezone(19801)
+
+
 def test_just_before_last_transition():
     tz = pendulum.timezone("Asia/Shanghai")
     dt = datetime(1991, 4, 20, 1, 49, 8, fold=0)