Fix timeZone handling for time arguments

Author: eemeli

fluent.runtime/fluent/runtime/types.py

@@ -371,7 +371,9 @@ def format(self, locale: Locale) -> str:
                 return format_date(selftz, format="medium", locale=locale)
             else:
                 return format_time(selftz, format=ts or "short", locale=locale)
-        elif ts is None:
+        assert not isinstance(selftz, time)
+
+        if ts is None:
             return format_date(selftz, format=ds, locale=locale)
 
         # Both date and time. Logic copied from babel.dates.format_datetime,
@@ -388,13 +390,24 @@ def format(self, locale: Locale) -> str:
 
 def _ensure_datetime_tzinfo(dt: Union[datetime, time], tzinfo: Union[str, None] = None) -> Union[datetime, time]:
     """
-    Ensure the datetime passed has an attached tzinfo.
+    Ensure the datetime or time passed has an attached tzinfo.
     """
-    # Adapted from babel's function.
+    if isinstance(dt, datetime):
+        # Adapted from babel's function.
+        if dt.tzinfo is None:
+            dt = dt.replace(tzinfo=pytz.UTC)
+        if tzinfo is not None:
+            dt = dt.astimezone(get_timezone(tzinfo))
+        return dt
     if dt.tzinfo is None:
-        dt = dt.replace(tzinfo=pytz.UTC)
-    if tzinfo is not None:
-        dt = dt.astimezone(get_timezone(tzinfo))
+        tz = get_timezone(tzinfo) if tzinfo is not None else pytz.UTC
+        return dt.replace(tzinfo=tz)
+    elif tzinfo is not None:
+        tz = get_timezone(tzinfo)
+        if tz != dt.tzinfo:
+            print(dt.tzinfo, tz)
+            raise TypeError("timezone conversion not supported for time values")
+
     return dt
 
 

fluent.runtime/tests/test_types.py

@@ -288,6 +288,14 @@ def test_timeZone(self):
         fd2d = fluent_date(dt1, timeStyle="short", timeZone="Europe/London")
         assert fd2d.format(en_GB) == "00:30"
 
+        ft = fluent_date(a_time, timeZone="UTC")
+        assert ft.format(en_GB) == "10:31"
+        ft = fluent_date(a_time, timeZone="Europe/London")
+        with pytest.raises(TypeError):
+            ft.format(en_GB)
+        ft = fluent_date(time(10, 31, 00, 333), timeZone="Europe/London")
+        assert ft.format(en_GB) == "10:31"
+
     def test_allow_unsupported_options(self):
         # We are just checking that these don't raise exceptions
         with warnings.catch_warnings():