code: def test_empty_string():
      """
      Test empty string is OK.
  
      https://github.com/jquast/wcwidth/issues/24
      """
      phrase = ""
      expect_length_each = 0
      expect_length_phrase = 0
  
      # exercise,
      length_each = wcwidth.wcwidth(phrase)
      length_phrase = wcwidth.wcswidth(phrase)
  
      # verify.
      assert length_each == expect_length_each
      assert length_phrase == expect_length_phrase
  
file_path: catboost/contrib/python/wcwidth/py2/tests/test_core.py
imports: import wcwidth
label_desc: Use image node_id 2 for calling a global function with example usage: test_empty_string() without return types