return offset-aware modification time (#818)

Author: malmans2

s3fs/core.py

@@ -1992,7 +1992,7 @@ def modified(self, path, version_id=None, refresh=False):
         if "LastModified" not in info:
             # This path is a bucket or folder, which do not currently have a modified date
             raise IsADirectoryError
-        return info["LastModified"].replace(tzinfo=None)
+        return info["LastModified"]
 
     def sign(self, path, expiration=100, **kwargs):
         return self.url(path, expires=expiration, **kwargs)

s3fs/tests/test_s3fs.py

@@ -2033,6 +2033,7 @@ def test_modified(s3):
     s3.touch(file_path)
     modified = s3.modified(path=file_path)
     assert isinstance(modified, datetime.datetime)
+    assert modified.tzinfo is not None
 
     # Test directory
     with pytest.raises(IsADirectoryError):