move stringify guard to types_filenames

Author: CRiddler

nibabel/filebasedimages.py

@@ -252,12 +252,10 @@ def set_filename(self, filename):
            ``.file_map`` attribute. Otherwise, the image instance will
            try and guess the other filenames from this given filename.
         '''
-        filename = _stringify_path(filename)
         self.file_map = self.__class__.filespec_to_file_map(filename)
 
     @classmethod
     def from_filename(klass, filename):
-        filename = _stringify_path(filename)
         file_map = klass.filespec_to_file_map(filename)
         return klass.from_file_map(file_map)
 
@@ -332,7 +330,6 @@ def to_filename(self, filename):
         -------
         None
         '''
-        filename = _stringify_path(filename)
         self.file_map = self.filespec_to_file_map(filename)
         self.to_file_map()
 

nibabel/filename_parser.py

@@ -107,6 +107,7 @@ def types_filenames(template_fname, types_exts,
     >>> tfns == {'t1': '/path/test.funny', 't2': '/path/test.ext2'}
     True
     '''
+    template_fname = _stringify_path(template_fname)
     if not isinstance(template_fname, str):
         raise TypesFilenamesError('Need file name as input '
                                   'to set_filenames')