ClickHouseBinaryFormatReader::getBigDecimal silently truncates large integer values #2748

new BigDecimal(reader.getString))

package org.example;

import java.math.BigDecimal;
import java.util.concurrent.CompletableFuture;

import com.clickhouse.client.api.Client;
import com.clickhouse.client.api.Client.Builder;
import com.clickhouse.client.api.data_formats.ClickHouseBinaryFormatReader;
import com.clickhouse.client.api.enums.Protocol;
import com.clickhouse.client.api.query.QueryResponse;

public final class WrongValue {

    public static void main(String[] args) throws Exception {
        Client client = new Builder()
            .addEndpoint(Protocol.HTTP, "127.0.0.1", 8123, false)
            .setUsername("user")
            .setPassword("123")
            .build();
        try (client) {
            String sql = "SELECT toInt64(%d)".formatted(Long.MAX_VALUE);
            CompletableFuture<QueryResponse> future = client.query(sql);
            QueryResponse response = future.get();
            try (ClickHouseBinaryFormatReader reader = client.newBinaryFormatReader(response)) {
                reader.next();
                BigDecimal actual = reader.getBigDecimal(1);
                BigDecimal expected = BigDecimal.valueOf(Long.MAX_VALUE);

                if (actual.compareTo(expected) != 0) {
                    System.err.printf("Got %s instead of expected %s%n", actual.toPlainString(), expected.toPlainString());
                }
            }
        }
    }
}