wrapAsExpression somehow makes program fail with "debug" log level

[Ktlo]

The code below works as expected, if log lever is lower than "debug", but otherwise it causes the NoSuchElementException.

package example

import org.jetbrains.exposed.dao.id.IntIdTable
import org.jetbrains.exposed.sql.*
import org.jetbrains.exposed.sql.transactions.transaction
import org.jetbrains.exposed.sql.transactions.transactionManager
import java.sql.Connection

object UserTable : IntIdTable() {
    val name = varchar("name", 64)
}
object OtherTable : Table() {
    val user = optReference("user", UserTable)

    // This property is important for some reason, there may be any other column
    val group = text("group")
}

fun main() {
    Database.connect("jdbc:sqlite:file:test?mode=memory&cache=shared").apply {
        transactionManager.defaultIsolationLevel = Connection.TRANSACTION_SERIALIZABLE
    }
    transaction {
        SchemaUtils.create(UserTable, OtherTable)
        UserTable.insert {
            it[name] = "sample"
        }
        OtherTable.insert {
            it[user] = wrapAsExpression(UserTable.slice(UserTable.id).select { UserTable.name eq "sample" })
            it[group] = ""
        }
    }
}

Output

19:08:41.011 [main] DEBUG Exposed - CREATE TABLE IF NOT EXISTS "User" (id INTEGER PRIMARY KEY AUTOINCREMENT, "name" VARCHAR(64) NOT NULL)
19:08:41.015 [main] DEBUG Exposed - CREATE TABLE IF NOT EXISTS "Group" (id INTEGER PRIMARY KEY AUTOINCREMENT, "name" VARCHAR(64) NOT NULL)
19:08:41.015 [main] DEBUG Exposed - CREATE TABLE IF NOT EXISTS Other ("user" INT NULL, "group" TEXT NOT NULL, CONSTRAINT fk_Other_user_id FOREIGN KEY ("user") REFERENCES "User"(id) ON DELETE RESTRICT ON UPDATE RESTRICT)
19:08:41.028 [main] DEBUG Exposed - INSERT INTO "User" ("name") VALUES ('sample')
Exception in thread "main" java.util.NoSuchElementException
	at java.util.ArrayList$Itr.next(ArrayList.java:862)
	at org.jetbrains.exposed.sql.statements.StatementKt.expandArgs(Statement.kt:98)
	at org.jetbrains.exposed.sql.Slf4jSqlDebugLogger.log(SQLLog.kt:32)
	at org.jetbrains.exposed.sql.CompositeSqlLogger.log(SQLLog.kt:50)
	at org.jetbrains.exposed.sql.CompositeSqlLogger.afterExecution(SQLLog.kt:56)
	at org.jetbrains.exposed.sql.statements.Statement.executeIn$exposed_core(Statement.kt:69)
	at org.jetbrains.exposed.sql.Transaction.exec(Transaction.kt:129)
	at org.jetbrains.exposed.sql.Transaction.exec(Transaction.kt:115)
	at org.jetbrains.exposed.sql.statements.Statement.execute(Statement.kt:29)
	at org.jetbrains.exposed.sql.QueriesKt.insert(Queries.kt:73)
	at example.ExampleKt$main$2.invoke(Example.kt:31)
	at example.ExampleKt$main$2.invoke(Example.kt)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt$inTopLevelTransaction$1.invoke(ThreadLocalTransactionManager.kt:170)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt$inTopLevelTransaction$2.invoke(ThreadLocalTransactionManager.kt:211)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt.keepAndRestoreTransactionRefAfterRun(ThreadLocalTransactionManager.kt:219)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt.inTopLevelTransaction(ThreadLocalTransactionManager.kt:210)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt$transaction$1.invoke(ThreadLocalTransactionManager.kt:148)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt.keepAndRestoreTransactionRefAfterRun(ThreadLocalTransactionManager.kt:219)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt.transaction(ThreadLocalTransactionManager.kt:120)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt.transaction(ThreadLocalTransactionManager.kt:118)
	at org.jetbrains.exposed.sql.transactions.ThreadLocalTransactionManagerKt.transaction$default(ThreadLocalTransactionManager.kt:117)
	at example.ExampleKt.main(Example.kt:26)
	at example.ExampleKt.main(Example.kt)

Environment

• Exposed version: 0.26.2
• Kotlin version: 1.3.72

[Tapac]

Thank you for a report, looks like there also was a place where SQL-injection could happen. It was also fixed.