[BUG] Serialization failure - some math function return NaN instead of NULL

[Yury-Fridlyand]

What is the bug?

Some math functions return ±NaN instead of NULL. NaN is not serializable by GSON lib.
For example, LN uses Math.log which returns -NaN for negative values.

sql/core/src/main/java/org/opensearch/sql/expression/operator/arthmetic/MathematicalFunction.java

Line 220 in 9d4a841

v -> new ExprDoubleValue(Math.log(v.doubleValue()))),

How can one reproduce the bug?

opensearchsql> select LN(-12.34567);
{'reason': 'Invalid SQL query', 'details': 'NaN is not a valid double value as per JSON specification. To override this behavior, use GsonBuilder.serializeSpecialFloatingPointValues() method.', 'type': 'IllegalArgumentException'}

What is the expected behavior?

mysql> select LN(-12.34567);
+---------------+
| LN(-12.34567) |
+---------------+
|          NULL |
+---------------+

What is your host/environment?

main @ 9d4a841

Do you have any additional context?

Fix all math functions or patch serializer callee in protocol module to replace all ±NaN by NULLs.

[Yury-Fridlyand]

Legacy engine fails as well:

$ curl -XPOST http://localhost:9200/_plugins/_sql -H 'Content-Type: application/json' -d '{"query": "SELECT LN(0)"}'
{
  "error": {
    "reason": "Invalid SQL query",
    "details": "-Infinity is not a valid double value as per JSON specification. To override this behavior, use GsonBuilder.serializeSpecialFloatingPointValues() method.",
    "type": "IllegalArgumentException"
  },
  "status": 400
}

$ curl -XPOST http://localhost:9200/_plugins/_sql -H 'Content-Type: application/json' -d '{"query": "SELECT LN(0) from books", "fetch_size": 10}'
JSON does not allow non-finite numbers.