Merge pull request #3525 from neutrinoceros/expanduser_from_dataset

ENH: allow direct dataset instanciation using the user path '~' glyph, consistently with yt.load

yt/data_objects/static_output.py

@@ -159,7 +159,7 @@ def __new__(cls, filename=None, *args, **kwargs):
             if not is_stream:
                 obj.__init__(filename, *args, **kwargs)
             return obj
-        apath = os.path.abspath(filename)
+        apath = os.path.abspath(os.path.expanduser(filename))
         cache_key = (apath, pickle.dumps(args), pickle.dumps(kwargs))
         if ytcfg.get("yt", "skip_dataset_cache"):
             obj = object.__new__(cls)
@@ -212,9 +212,10 @@ def __init__(
         self.default_species_fields = default_species_fields
 
         # path stuff
-        self.parameter_filename = str(filename)
+        filename = os.path.expanduser(filename)
+        self.parameter_filename = filename
         self.basename = os.path.basename(filename)
-        self.directory = os.path.expanduser(os.path.dirname(filename))
+        self.directory = os.path.dirname(filename)
         self.fullpath = os.path.abspath(self.directory)
         self.backup_filename = self.parameter_filename + "_backup.gdf"
         self.read_from_backup = False

yt/loaders.py

@@ -69,7 +69,7 @@ def load(fn, *args, **kwargs):
     yt.utilities.exceptions.YTAmbiguousDataType
         If the data format matches more than one class of similar specilization levels.
     """
-    fn = os.path.expanduser(fn)
+    fn = os.fspath(fn)
 
     if any(wildcard in fn for wildcard in "[]?!*"):
         from yt.data_objects.time_series import DatasetSeries