updated _translate_sheet_name(): substitute special characters by underscores in sheet_name if it is a string and not only a Group

Author: alixdamman

larray/core/group.py

@@ -654,9 +654,11 @@ def _to_keys(value, stack_depth=1):
 
 def _translate_sheet_name(sheet_name):
     if isinstance(sheet_name, Group):
-        sheet_name = _sheet_name_pattern.sub('_', str(_to_tick(sheet_name)))
-    if isinstance(sheet_name, basestring) and len(sheet_name) > 30:
-        raise ValueError("Sheet names cannot exceed 31 characters")
+        sheet_name = str(_to_tick(sheet_name))
+    if isinstance(sheet_name, basestring):
+        sheet_name = _sheet_name_pattern.sub('_', sheet_name)
+        if len(sheet_name) > 30:
+            raise ValueError("Sheet names cannot exceed 31 characters")
     return sheet_name