class_docstr: Test index for :meth:`orion.core.io.database.ephemeraldb.EphemeralCollection`.
docstr: Test if index values are tracked property.
docstr_tok: ["Test","if","index","values","are","tracked","property","."]
code: def test_index_over_non_existing_field(self, collection):
      """Test if index values are tracked property."""
      collection.create_index(
          [
              ("hello", Database.DESCENDING),
              ("idontexist", Database.ASCENDING),
          ],
          unique=True,
      )
  
      collection.insert_many([{"hello": "here"}, {"hello": 2}])
      assert collection._indexes == {
          "_id_": (("_id",), {(1,), (2,), (3,)}),
          "hello_1_idontexist_1": (
              ("hello", "idontexist"),
              {("there", None), ("here", None), (2, None)},
          ),
      }
      assert collection.find(
          {}, selection={"hello": 1, "idontexist": 1}
      ) == [
          {"_id": 1, "hello": "there", "idontexist": None},
          {"_id": 2, "hello": "here", "idontexist": None},
          {"_id": 3, "hello": 2, "idontexist": None},
      ]
  
imports: import pytest
  from orion.core.io.database import Database
  from orion.core.io.database.ephemeraldb import EphemeralCollection, EphemeralDB, EphemeralDocument
label_desc: Use image node_id 3 for calling the TestIndex obj's underlying member method code with example usage: obj.test_index_over_non_existing_field(collection) without return types