code: def test_empty_more_like(model=classify.Bo1Model):
      schema = fields.Schema(text=fields.TEXT)
      with TempIndex(schema, "emptymore") as ix:
          with ix.searcher() as s:
              assert s.doc_count() == 0
              q = query.Term("a", u("b"))
              r = s.search(q)
              assert r.scored_length() == 0
              assert r.key_terms("text", model=model) == []
  
              ex = classify.Expander(s.reader(), "text", model=model)
              assert ex.expanded_terms(1) == []
  
file_path: whoosh/tests/test_classify.py
imports: from __future__ import with_statement
  from whoosh import analysis, classify, fields, formats, query, reading
  from whoosh.compat import u, text_type
  from whoosh.filedb.filestore import RamStorage
  from whoosh.util.testing import TempIndex
label_desc: Use image node_id 7 for calling a global function with example usage: test_empty_more_like(model) without return types