def METHOD_NAME(self) -> None:
    """
    Individual cache factors defined in the environment will take precedence
    over those in the config.
    """
    config: JsonDict = {"caches": {"per_cache_factors": {"foo": 2, "bar": 3}}}
    self.config._environ = {
        "SYNAPSE_CACHE_FACTOR_SOMETHING_OR_OTHER": "2",
        "SYNAPSE_CACHE_FACTOR_FOO": "1",
    }
    self.config.read_config(config, config_dir_path="", data_dir_path="")
    self.config.resize_all_caches()
    self.assertEqual(
        dict(self.config.cache_factors),
        {"foo": 1.0, "bar": 3.0, "something_or_other": 2.0},
    )