def METHOD_NAME(self):
    """Defining an empty mapping value is not allowed"""
    text = dedent(
        """
    ---
    test_name: Test cannot send a set
    stages:
      - name: match top level
        request:
          url: "{host}/fake_dictionary"
          method: GET
          json: {a, b}
        response:
          status_code: 200
          json:
            top: !anything
    """
    )
    with TestBadSchemaAtCollect.wrapfile_nondict(text) as filename:
        with pytest.raises(BadSchemaError):
            load_single_document_yaml(filename)