private function arrayDiffAssoc( array $from, array $to ): array {
		$diff = [];

		foreach ( $from as $key => $value ) {
			if ( !array_key_exists( $key, $to ) || !$this->valueComparer->valuesAreEqual( $to[$key], $value ) ) {
				$diff[$key] = $value;
			}
		}

		return $diff;
	}