FIX: Coerce license path to pathlike

Author: mgxd

wrapper/fmriprep_docker.py

@@ -237,6 +237,7 @@ def __call__(self, parser, namespace, values, option_string=None):
 
     def _is_file(path, parser):
         """Ensure a given path exists and it is a file."""
+        path = os.path.abspath(path)
         if not os.path.isfile(path):
             raise parser.error(
                 "Path should point to a file (or symlink of file): <%s>." % path