Function ARRAY_INSERT produces an incorrect result for negative indices

Here is a test taken from the Spark documentation page:
https://spark.apache.org/docs/latest/api/sql/index.html#array_insert

SELECT array_insert(array(5, 3, 2, 1), -4, 4);
[5,4,3,2,1]

The result produced by Calcite is:

[4,5,3,2,1]

The strange thing is that there are tests for negative indices. I wonder if the original tests are wrong, or the behavior of this function in Spark was changed since the tests were written.